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Mmbaga AT, Lwetoijera DW. Current and future opportunities of autodissemination of pyriproxyfen approach for malaria vector control in urban and rural Africa. Wellcome Open Res 2023; 8:119. [PMID: 37440995 PMCID: PMC10333782 DOI: 10.12688/wellcomeopenres.19131.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/23/2023] [Indexed: 07/15/2023] Open
Abstract
Despite the progress made in reducing malaria burden, new ways to address the increasing challenges of insecticide resistance and the invasion and spread of exotic malaria vectors such as Anopheles stephensi in Africa are urgently needed. While African countries are adopting larviciding as a complementary intervention for malaria vector control, the autodissemination technology has the potential to overcome barriers associated with the identification and treatment of prolific habitats that impede conventional larviciding approaches in rural settings. The autodissemination technology as a "lure and release" strategy works by exploiting the resting behavior of gravid mosquitoes to transfer lethal concentration of biological or chemical insecticide such as pyriproxyfen (PPF), an insect growth regulator (IGRs) to their oviposition sites and result in adult emergence inhibition. Despite the evidence of the autodissemination approach to control other mosquito-borne diseases, there is growing and promising evidence for its use in controlling malaria vectors in Africa, which highlights the momentous research that needs to be sustained. This article reviews the evidence for efficacy of the autodissemination approach using PPF and discusses its potential as efficient and affordable complementary malaria vector control intervention in Africa. In the previous studies that were done in controlled semi-field environments, autodissemination with PPF demonstrated its potential in reducing densities of captive population of malaria vectors such as Anopheles gambiae and Anopheles arabiensis. Of importance, empirical evidence and biology-informed mathematical models to demonstrate the utility of the autodissemination approach to control wild populations of malaria vectors under field environment either alone or in combination with other tools are underway. Among others, the key determining factors for future introduction of this approach at scale is having scalable autodissemination devices, optimized PPF formulations, assess its integration/complementarity to existing conventional larviciding, and community perception and acceptance of the autodissemination approach.
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Affiliation(s)
- Augustino Thabiti Mmbaga
- Environmental Health and Ecological Science Department, Ifakara Health Institute, Ifakara, Morogoro, P.O. Box 53, Tanzania
| | - Dickson Wilson Lwetoijera
- Environmental Health and Ecological Science Department, Ifakara Health Institute, Ifakara, Morogoro, P.O. Box 53, Tanzania
- School of Life Sciences and Bio Engineering, Nelson Mandela African Institution of Science and Technology, Tengeru, Arusha, P.O. Box 447, Tanzania
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Tchouakui M, Thiomela RF, Nchoutpouen E, Menze BD, Ndo C, Achu D, Tabue RN, Njiokou F, Joel A, Wondji CS. High efficacy of chlorfenapyr-based net Interceptor ® G2 against pyrethroid-resistant malaria vectors from Cameroon. Infect Dis Poverty 2023; 12:81. [PMID: 37641108 PMCID: PMC10463949 DOI: 10.1186/s40249-023-01132-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/21/2023] [Indexed: 08/31/2023] Open
Abstract
BACKGROUND The increasing reports of resistance to pyrethroid insecticides associated with reduced efficacy of pyrethroid-only interventions highlight the urgency of introducing new non-pyrethroid-only control tools. Here, we investigated the performance of piperonyl-butoxide (PBO)-pyrethroid [Permanet 3.0 (P3.0)] and dual active ingredients (AI) nets [Interceptor G2 (IG2): containing pyrethroids and chlorfenapyr and Royal Guard (RG): containing pyrethroids and pyriproxyfen] compared to pyrethroid-only net Royal Sentry (RS) against pyrethroid-resistant malaria vectors in Cameroon. METHODS The efficacy of these tools was firstly evaluated on Anopheles gambiae s.l. and Anopheles funestus s.l. from Gounougou, Mibellon, Mangoum, Nkolondom, and Elende using cone/tunnel assays. In addition, experimental hut trials (EHT) were performed to evaluate the performance of unwashed and 20 times washed nets in semi-field conditions. Furthermore, pyrethroid-resistant markers were genotyped in dead vs alive, blood-fed vs unfed mosquitoes after exposure to the nets to evaluate the impact of these markers on net performance. The XLSTAT software was used to calculate the various entomological outcomes and the Chi-square test was used to compare the efficacy of various nets. The odds ratio and Fisher exact test were then used to establish the statistical significance of any association between insecticide resistance markers and bed net efficacy. RESULTS Interceptor G2 was the most effective net against wild pyrethroid-resistant An. funestus followed by Permanet 3.0. In EHT, this net induced up to 87.8% mortality [95% confidence interval (CI): 83.5-92.1%) and 55.6% (95% CI: 48.5-62.7%) after 20 washes whilst unwashed pyrethroid-only net (Royal Sentry) killed just 18.2% (95% CI: 13.4-22.9%) of host-seeking An. funestus. The unwashed Permanet 3.0 killed up to 53.8% (95% CI: 44.3-63.4%) of field-resistant mosquitoes and 47.2% (95% CI: 37.7-56.7%) when washed 20 times, and the Royal Guard 13.2% (95% CI: 9.0-17.3%) for unwashed net and 8.5% (95% CI: 5.7-11.4%) for the 20 washed net. Interceptor G2, Permanet 3.0, and Royal Guard provided better personal protection (blood-feeding inhibition 66.2%, 77.8%, and 92.8%, respectively) compared to pyrethroid-only net Royal Sentry (8.4%). Interestingly, a negative association was found between kdrw and the chlorfenapyr-based net Interceptor G2 (χ2 = 138; P < 0.0001) with homozygote-resistant mosquitoes predominantly found in the dead ones. CONCLUSIONS The high mortality recorded with Interceptor G2 against pyrethroid-resistant malaria vectors in this study provides first semi-field evidence of high efficacy against these major malaria vectors in Cameroon encouraging the implementation of this novel net for malaria control in the country. However, the performance of this net should be established in other locations and on other major malaria vectors before implementation at a large scale.
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Affiliation(s)
- Magellan Tchouakui
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13501, Yaoundé, Cameroon.
| | - Riccado F Thiomela
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13501, Yaoundé, Cameroon
- Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
| | - Elysee Nchoutpouen
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13501, Yaoundé, Cameroon
| | - Benjamin D Menze
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13501, Yaoundé, Cameroon
| | - Cyrille Ndo
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13501, Yaoundé, Cameroon
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon
| | - Dorothy Achu
- Ministry of Public Health, National Malaria Control Programme, P.O. Box 14386, Yaounde, Cameroon
| | - Raymond N Tabue
- Ministry of Public Health, National Malaria Control Programme, P.O. Box 14386, Yaounde, Cameroon
| | - Flobert Njiokou
- Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
| | - Ateba Joel
- Ministry of Public Health, National Malaria Control Programme, P.O. Box 14386, Yaounde, Cameroon
| | - Charles S Wondji
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13501, Yaoundé, Cameroon.
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L35QA, UK.
- International Institute of Tropical Agriculture (IITA), P.O. Box 2008, Yaoundé, Cameroon.
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Syme T, N'dombidjé B, Gbegbo M, Todjinou D, Ariori V, De Vos P, Pigeon O, Ngufor C. PermaNet Dual, a new deltamethrin-chlorfenapyr mixture net, shows improved efficacy against pyrethroid-resistant Anopheles gambiae sensu lato in southern Benin. Sci Rep 2023; 13:12232. [PMID: 37507423 PMCID: PMC10382523 DOI: 10.1038/s41598-023-39140-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
Pyrethroid-chlorfenapyr nets have demonstrated improved entomological and epidemiological impact in trials across Africa. This is driving increased demand for this novel net class in malaria-endemic countries. PermaNet Dual is a new deltamethrin-chlorfenapyr net developed by Vestergaard Sàrl to provide more options to malaria control programmes. We performed an experimental hut trial to evaluate the efficacy of PermaNet Dual against wild, free-flying pyrethroid-resistant Anopheles gambiae sensu lato in Covè, Benin. PermaNet Dual induced superior levels of mosquito mortality compared to a pyrethroid-only net and a pyrethroid-piperonyl butoxide net both when unwashed (77% with PermaNet Dual vs. 23% with PermaNet 2.0 and 56% with PermaNet 3.0, p < 0.001) and after 20 standardised washes (75% with PermaNet Dual vs. 14% with PermaNet 2.0 and 30% with PermaNet 3.0, p < 0.001). Using a provisional non-inferiority margin defined by the World Health Organisation, PermaNet Dual was also non-inferior to a pyrethroid-chlorfenapyr net that has demonstrated improved public health value (Interceptor G2), for vector mortality (79% vs. 76%, OR = 0.878, 95% CIs 0.719-1.073) but not for blood-feeding protection (35% vs. 26%, OR = 1.424, 95% CIs 1.177-1.723). PermaNet Dual presents an additional option of this highly effective net class for improved control of malaria transmitted by pyrethroid-resistant mosquitoes.
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Affiliation(s)
- Thomas Syme
- London School of Hygiene & Tropical Medicine, London, UK.
- Centre de Recherche Entomologique de Cotonou, Cotonou, Benin.
- Pan African Malaria Vector Research Consortium (PAMVERC), Cotonou, Benin.
| | - Boris N'dombidjé
- Centre de Recherche Entomologique de Cotonou, Cotonou, Benin
- Pan African Malaria Vector Research Consortium (PAMVERC), Cotonou, Benin
| | - Martial Gbegbo
- Centre de Recherche Entomologique de Cotonou, Cotonou, Benin
- Pan African Malaria Vector Research Consortium (PAMVERC), Cotonou, Benin
| | - Damien Todjinou
- Centre de Recherche Entomologique de Cotonou, Cotonou, Benin
- Pan African Malaria Vector Research Consortium (PAMVERC), Cotonou, Benin
| | - Victoria Ariori
- Centre de Recherche Entomologique de Cotonou, Cotonou, Benin
- Pan African Malaria Vector Research Consortium (PAMVERC), Cotonou, Benin
| | - Patricia De Vos
- Centre Walloon de Recherches Agronomiques (CRA-W), Gembloux, Belgium
| | - Olivier Pigeon
- Centre Walloon de Recherches Agronomiques (CRA-W), Gembloux, Belgium
| | - Corine Ngufor
- London School of Hygiene & Tropical Medicine, London, UK.
- Centre de Recherche Entomologique de Cotonou, Cotonou, Benin.
- Pan African Malaria Vector Research Consortium (PAMVERC), Cotonou, Benin.
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Tetteh J, Yorke E, Boima V, Yawson AE. Prevalence of malaria infection and the impact of mosquito bed net distribution among children aged 6-59 months in Ghana: Evidence from the Ghana demographic health and malarial indicator surveys. Parasite Epidemiol Control 2023; 21:e00302. [PMID: 37200871 PMCID: PMC10185735 DOI: 10.1016/j.parepi.2023.e00302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 04/24/2023] [Accepted: 04/24/2023] [Indexed: 05/20/2023] Open
Abstract
Objective To assess the prevalence of malaria infection and further quantify the impact of mosquito bed net distribution on malaria infection among children aged 6-59 months in Ghana. Methods A cross-sectional study using Ghana Demographic Health (GDHS) and Malaria Indicator (GMIS) surveys (2014 GDHS, 2016 GMIS, and 2019 GMIS). The exposure and the main outcomes were mosquito bed net use (MBU) and malaria infection (MI). Relative percentage change (Δ) and prevalence ratio (PR) were estimated to assess the changes and the risk of MI by MBU respectively. The Propensity-score matching treatment effect model was employed to estimate the average treatment effect (ATE) of MBU on MI. All analyses were performed using Stata 16.1 and p-value<0.05 was deemed significant. Results The study involved 8781 children aged 6-59 months. MI ranged from 25.8%(22.3-29.7) in 2019 GMIS to 40.6%(37.0-44.2) in 2014 GDHS and the prevalence was significantly high among children who used mosquito bed net. The relative percentage change in MI prevalence showed a significant reduction rate and was high among non-MBU (p-value<0.05). In all, the adjusted PR of MI among children exposed to MBU was 1.21(1.08-1.35), 1.13(1.01-1.28), and 1.50(1.20-1.75) in 2014 GDHS, 2016 GMIS, and 2019 GMIS respectively. The average MI among participants who slept in mosquito bed net significantly increased by 8%(0.04 to 0.12), 4%(0.003 to 0.08), and 7%(0.03 to 0.11) in 2014 GDHS, 2016 GMIS, and 2019 GMIS respectively. Conclusion Even though malaria infection prevalence among children aged 6-59 months is decreasing, the reduction rate seems not to be directly linked with mosquito bed nets distribution and/or use in Ghana. For a continued distribution of mosquito bed nets, and for Ghana to achieve her Malaria Strategic Plan (NMSP) 2021-2025, program managers should ensure effective use of the distributed nets in addition to other preventive measures and nuanced consideration of community behaviours in Ghana. The effective use and care of bed nets should be emphasized as part of the distribution.
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Affiliation(s)
- John Tetteh
- Department of Community Health, University of Ghana Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
- Corresponding author at: Department of Community Health, University of Ghana Medical School, College of Health Sciences, P.O. Box 4236, Accra, Ghana.
| | - Ernest Yorke
- Department of Medicine and Therapeutics, University of Ghana Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Vincent Boima
- Department of Medicine and Therapeutics, University of Ghana Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Alfred Edwin Yawson
- Department of Community Health, University of Ghana Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
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Mmbaga AT, Lwetoijera DW. Current and future opportunities of autodissemination of pyriproxyfen approach for malaria vector control in urban and rural Africa. Wellcome Open Res 2023. [DOI: 10.12688/wellcomeopenres.19131.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
Abstract
Despite the progress made in reducing malaria burden, new ways to address the increasing challenges of insecticide resistance and the invasion and spread of exotic malaria vectors such as Anopheles stephensi in Africa are urgently needed. While African countries are adopting larviciding as a complementary intervention for malaria vector control, the autodissemination technology has the potential to overcome barriers associated with the identification and treatment of prolific habitats that impede conventional larviciding approaches in rural settings. The autodissemination technology as a “lure and release” strategy works by exploiting the resting behavior of gravid mosquitoes to transfer lethal concentration of biological or chemical insecticide such as pyriproxyfen (PPF), an insect growth regulator (IGRs) to their oviposition sites and result in adult emergence. Despite the evidence of the autodissemination approach to control other mosquito-borne diseases, there is growing and promising evidence for its use in controlling malaria vectors in Africa, which highlights the momentous research that needs to be sustained. This article reviews the evidence for efficacy of the autodissemination approach using PPF and discusses its potential as efficient and affordable complementary malaria vector control intervention in Africa. In the previous studies that were done in controlled semi-field environments, autodissemination with PPF demonstrated its potential in reducing densities of captive population of malaria vectors such as Anopheles gambiae and Anopheles arabiensis. Of importance, empirical evidence and biology-informed mathematical models to demonstrate the utility of the autodissemination approach to control wild populations of malaria vectors under field environment either alone or in combination with other tools are underway. Among others, the key determining factors for future introduction of this approach at scale is having scalable autodissemination devices, optimized PPF formulations, assess its integration/complementarity to existing conventional larviciding, and community perception and acceptance of the autodissemination approach.
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Likwela JL, Ngwala PL, Ntumba AK, Ntale DC, Sompwe EM, Mpiana GK, Tshula JK, Likwela TK, Kanku-Ka-Munabe P, Kumbi AN', Ndahambara GK, Ntale HC, Kiamenga ML, Njila JK, Yav GM, Baneti DG, Austin J. Digitalized long-lasting insecticidal nets mass distribution campaign in the context of Covid-19 pandemic in Kongo Central, Democratic Republic of Congo: challenges and lessons learned. Malar J 2022; 21:253. [PMID: 36050676 PMCID: PMC9434528 DOI: 10.1186/s12936-022-04258-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 08/09/2022] [Indexed: 11/20/2022] Open
Abstract
Background The Democratic Republic of the Congo (DRC) organized a first mass distribution campaign of long-lasting insecticidal nets (LLINs) with digitalized data management with coordinated support from the Ministry of Health (MOH) and Santé Pour Tous En Milieu Rural—an ‘Association sans but lucratif’ (SANRU Asbl), in the context of the Covid-19 pandemic in Kongo Central province. This article describes the planning and implementation process of this campaign as well as the challenges and lessons learned. Methods The planning and implementation process was performed in line with the standard guidance issued by the National Malaria Control Programme (NMCP) following the start of Covid-19. The changes and adaptations put in place as well as the challenges encountered are described. Results A total of 5,629,211 people were registered (7.7% above projection) in 1,065,537 households (6.2% below projection) giving an average of 5.3 people per household. Of a total of 3,062,850 LLINs ordered, 2,886,096 were distributed to households (94%). Out of 11,070 villages and 3,947 teams planned, 91.7% of villages were reached and 93% of teams were established. Conclusion The revision of standards of campaign implementation during Covid-19, as well as effective coordination supported by real-time decision-making through digital data management, have been factors in the success of this campaign. Maintaining this momentum is essential to ensure the continuity of malaria prevention services for the population.
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Affiliation(s)
- Joris Losimba Likwela
- University of Kisangani, Kisangani, Democratic Republic of the Congo. .,Sanru Asbl, Kinshasa, Democratic Republic of the Congo.
| | | | | | | | - Eric Mukomena Sompwe
- National Malaria Control Programme, Kinshasa, Democratic Republic of the Congo.,School of Public Health, University of Lubumbashi, Lubumbashi, Democratic Republic of the Congo
| | - Godé Kanyeba Mpiana
- National Malaria Control Programme, Kinshasa, Democratic Republic of the Congo
| | | | | | | | | | | | | | | | | | - Ghislain Makhan Yav
- Cellule d'Appui à la Gestion Financière, Ministère de la Santé, Kinshasa, Democratic Republic of the Congo
| | - Didier Gasigwa Baneti
- Cellule d'Appui à la Gestion Financière, Ministère de la Santé, Kinshasa, Democratic Republic of the Congo
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Zoh MG, Tutagata J, Fodjo BK, Mouhamadou CS, Sadia CG, McBeath J, Schmitt F, Horstmann S, David JP, Reynaud S. Exposure of Anopheles gambiae larvae to a sub-lethal dose of an agrochemical mixture induces tolerance to adulticides used in vector control management. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 248:106181. [PMID: 35504174 DOI: 10.1016/j.aquatox.2022.106181] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 04/19/2022] [Accepted: 04/24/2022] [Indexed: 06/14/2023]
Abstract
The heavy use of pesticides in agricultural areas often leads to the contamination of nearby mosquito larvae breeding sites. Exposure to complex mixtures of agrochemicals can affect the insecticide sensitivity of mosquito larvae. Our study objective was to determine whether agrochemical residues in Anopheline larval breeding sites can affect the tolerance of adults to commonly used adulticides. We focussed on Fludora® Fusion, a vector control insecticide formulation combining two insecticides (deltamethrin and clothianidin) with different modes of action. An. gambiae larvae were exposed to a sub-lethal dose of a mixture of agrochemical pesticides used in a highly active agricultural area on the Ivory Coast. Comparative bioassays with Fludora Fusion mixture and its two insecticide components (deltamethrin and clothianidin) were carried out between adult mosquitoes exposed or not to the agrochemicals at the larval stage. A transcriptomic analysis using RNA sequencing was then performed on larvae and adults to study the molecular mechanisms underlying the phenotypic changes observed. Bioassays revealed a significantly increased tolerance of adult females to clothianidin (2.5-fold) and Fludora Fusion mixture (2.2-fold) following larval exposure to agrochemicals. Significantly increased tolerance to deltamethrin was not observed suggesting that insecticide exposure affects the adult efficacy of the Fludora Fusion mixture mainly through mechanisms acting on clothianidin. Transcriptomic analysis revealed the potential of agrochemicals to induce various resistance mechanisms including cuticle proteins, detoxification action and altered insecticide sequestration. These results suggest that although the Fludora Fusion mixture is effective for adult vector control, its efficacy may be locally affected by the ecological context. The present study also suggests that, although the complex interactions between the use of agrochemicals and vector control insecticides are difficult to decipher in the field, they still must be considered in the context of insecticide resistance management programmes.
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Affiliation(s)
- Marius Gonse Zoh
- Univ. Grenoble-Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, 38000 Grenoble, France.
| | - Jordan Tutagata
- Univ. Grenoble-Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, 38000 Grenoble, France.
| | - Behi K Fodjo
- Centre Suisse de la Recherche Scientifique en Côte d'Ivoire, Côte d'Ivoire
| | | | | | | | | | | | - Jean-Philippe David
- Univ. Grenoble-Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, 38000 Grenoble, France.
| | - Stéphane Reynaud
- Univ. Grenoble-Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, 38000 Grenoble, France.
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Sharma R, Aashima, Nanda M, Fronterre C, Sewagudde P, Ssentongo AE, Yenney K, Arhin ND, Oh J, Amponsah-Manu F, Ssentongo P. Mapping Cancer in Africa: A Comprehensive and Comparable Characterization of 34 Cancer Types Using Estimates From GLOBOCAN 2020. Front Public Health 2022; 10:839835. [PMID: 35548083 PMCID: PMC9082420 DOI: 10.3389/fpubh.2022.839835] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/10/2022] [Indexed: 01/22/2023] Open
Abstract
Objective Cancer incidence and mortality rates in Africa are increasing, yet their geographic distribution and determinants are incompletely characterized. The present study aims to establish the spatial epidemiology of cancer burden in Africa and delineate the association between cancer burden and the country-level socioeconomic status. The study also examines the forecasts of the cancer burden for 2040 and evaluates infrastructure availability across all African countries. Methods The estimates of age, sex, and country-specific incidence and mortality of 34 neoplasms in 54 African countries, were procured from GLOBOCAN 2020. Mortality-to-incidence ratio (MIR) was employed as a proxy indicator of 5-year survival rates, and the socioeconomic development of each country was measured using its human development index (HDI). We regressed age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and MIR on HDI using linear regression model to determine the relationship between cancer burden and HDI. Maps were generated for each cancer group for each country in Africa. The data about the cancer infrastructure of African countries were extracted from the WHO Cancer Country Profiles. Results In Africa, an estimated 1.1 million new cases [95% uncertainty intervals (UIs) 1.0 - 1.3 million] and 711,429 [611,604 - 827,547] deaths occurred due to neoplasms in 2020. The ASIR was estimated to be 132.1/100,000, varying from 78.4/100,000 (Niger) to 212.5/100,000 (La Réunion) in 2020. The ASMR was 88.8/100,000 in Africa, ranging from 56.6/100,000 in the Republic of the Congo to 139.4/100,000 in Zimbabwe. The MIR of all cancer combined was 0.64 in Africa, varying from 0.49 in Mauritius to 0.78 in The Gambia. HDI had a significant negative correlation with MIR of all cancer groups combined and main cancer groups (prostate, breast, cervical and colorectal). HDI explained 75% of the variation in overall 5-year cancer survival (MIR). By 2040, the burden of all neoplasms combined is forecasted to increase to 2.1 million new cases and 1.4 million deaths in Africa. Conclusion High cancer mortality rates in Africa demand a holistic approach toward cancer control and management, including, but not limited to, boosting cancer awareness, adopting primary and secondary prevention, mitigating risk factors, improving cancer infrastructure and timely treatment.
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Affiliation(s)
- Rajesh Sharma
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Aashima
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Mehak Nanda
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Claudio Fronterre
- Centre for Health Informatics, Computing, and Statistics, Lancaster University, Lancaster, United Kingdom
| | | | - Anna E. Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States
- Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | - Kelsey Yenney
- Washington State University Elson S. Floyd College of Medicine, Seattle, WA, United States
| | - Nina D. Arhin
- Division of Hematology/Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - John Oh
- Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | | | - Paddy Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States
- Center for Neural Engineering, The Pennsylvania State University, State College, PA, United States
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Sharma R, Aashima, Nanda M, Fronterre C, Sewagudde P, Ssentongo AE, Yenney K, Arhin ND, Oh J, Amponsah-Manu F, Ssentongo P. Mapping Cancer in Africa: A Comprehensive and Comparable Characterization of 34 Cancer Types Using Estimates From GLOBOCAN 2020. Front Public Health 2022; 10:839835. [PMID: 35548083 PMCID: PMC9082420 DOI: 10.3389/fpubh.2022.839835 10.3389/fpubh.2022.839835/full#:~:text=we%20examined%20the%20burden%20of,29)%20to%20711%2c000%20in%202020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Objective Cancer incidence and mortality rates in Africa are increasing, yet their geographic distribution and determinants are incompletely characterized. The present study aims to establish the spatial epidemiology of cancer burden in Africa and delineate the association between cancer burden and the country-level socioeconomic status. The study also examines the forecasts of the cancer burden for 2040 and evaluates infrastructure availability across all African countries. Methods The estimates of age, sex, and country-specific incidence and mortality of 34 neoplasms in 54 African countries, were procured from GLOBOCAN 2020. Mortality-to-incidence ratio (MIR) was employed as a proxy indicator of 5-year survival rates, and the socioeconomic development of each country was measured using its human development index (HDI). We regressed age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and MIR on HDI using linear regression model to determine the relationship between cancer burden and HDI. Maps were generated for each cancer group for each country in Africa. The data about the cancer infrastructure of African countries were extracted from the WHO Cancer Country Profiles. Results In Africa, an estimated 1.1 million new cases [95% uncertainty intervals (UIs) 1.0 - 1.3 million] and 711,429 [611,604 - 827,547] deaths occurred due to neoplasms in 2020. The ASIR was estimated to be 132.1/100,000, varying from 78.4/100,000 (Niger) to 212.5/100,000 (La Réunion) in 2020. The ASMR was 88.8/100,000 in Africa, ranging from 56.6/100,000 in the Republic of the Congo to 139.4/100,000 in Zimbabwe. The MIR of all cancer combined was 0.64 in Africa, varying from 0.49 in Mauritius to 0.78 in The Gambia. HDI had a significant negative correlation with MIR of all cancer groups combined and main cancer groups (prostate, breast, cervical and colorectal). HDI explained 75% of the variation in overall 5-year cancer survival (MIR). By 2040, the burden of all neoplasms combined is forecasted to increase to 2.1 million new cases and 1.4 million deaths in Africa. Conclusion High cancer mortality rates in Africa demand a holistic approach toward cancer control and management, including, but not limited to, boosting cancer awareness, adopting primary and secondary prevention, mitigating risk factors, improving cancer infrastructure and timely treatment.
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Affiliation(s)
- Rajesh Sharma
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Aashima
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Mehak Nanda
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Claudio Fronterre
- Centre for Health Informatics, Computing, and Statistics, Lancaster University, Lancaster, United Kingdom
| | | | - Anna E. Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States,Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | - Kelsey Yenney
- Washington State University Elson S. Floyd College of Medicine, Seattle, WA, United States
| | - Nina D. Arhin
- Division of Hematology/Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - John Oh
- Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | | | - Paddy Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States,Center for Neural Engineering, The Pennsylvania State University, State College, PA, United States,*Correspondence: Paddy Ssentongo
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Sharma R, Aashima, Nanda M, Fronterre C, Sewagudde P, Ssentongo AE, Yenney K, Arhin ND, Oh J, Amponsah-Manu F, Ssentongo P. Mapping Cancer in Africa: A Comprehensive and Comparable Characterization of 34 Cancer Types Using Estimates From GLOBOCAN 2020. Front Public Health 2022; 10:839835. [PMID: 35548083 PMCID: PMC9082420 DOI: 10.3389/fpubh.2022.839835 10.3389/fpubh.2022.839835/full] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVE Cancer incidence and mortality rates in Africa are increasing, yet their geographic distribution and determinants are incompletely characterized. The present study aims to establish the spatial epidemiology of cancer burden in Africa and delineate the association between cancer burden and the country-level socioeconomic status. The study also examines the forecasts of the cancer burden for 2040 and evaluates infrastructure availability across all African countries. METHODS The estimates of age, sex, and country-specific incidence and mortality of 34 neoplasms in 54 African countries, were procured from GLOBOCAN 2020. Mortality-to-incidence ratio (MIR) was employed as a proxy indicator of 5-year survival rates, and the socioeconomic development of each country was measured using its human development index (HDI). We regressed age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and MIR on HDI using linear regression model to determine the relationship between cancer burden and HDI. Maps were generated for each cancer group for each country in Africa. The data about the cancer infrastructure of African countries were extracted from the WHO Cancer Country Profiles. RESULTS In Africa, an estimated 1.1 million new cases [95% uncertainty intervals (UIs) 1.0 - 1.3 million] and 711,429 [611,604 - 827,547] deaths occurred due to neoplasms in 2020. The ASIR was estimated to be 132.1/100,000, varying from 78.4/100,000 (Niger) to 212.5/100,000 (La Réunion) in 2020. The ASMR was 88.8/100,000 in Africa, ranging from 56.6/100,000 in the Republic of the Congo to 139.4/100,000 in Zimbabwe. The MIR of all cancer combined was 0.64 in Africa, varying from 0.49 in Mauritius to 0.78 in The Gambia. HDI had a significant negative correlation with MIR of all cancer groups combined and main cancer groups (prostate, breast, cervical and colorectal). HDI explained 75% of the variation in overall 5-year cancer survival (MIR). By 2040, the burden of all neoplasms combined is forecasted to increase to 2.1 million new cases and 1.4 million deaths in Africa. CONCLUSION High cancer mortality rates in Africa demand a holistic approach toward cancer control and management, including, but not limited to, boosting cancer awareness, adopting primary and secondary prevention, mitigating risk factors, improving cancer infrastructure and timely treatment.
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Affiliation(s)
- Rajesh Sharma
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Aashima
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Mehak Nanda
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Claudio Fronterre
- Centre for Health Informatics, Computing, and Statistics, Lancaster University, Lancaster, United Kingdom
| | | | - Anna E. Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States,Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | - Kelsey Yenney
- Washington State University Elson S. Floyd College of Medicine, Seattle, WA, United States
| | - Nina D. Arhin
- Division of Hematology/Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - John Oh
- Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | | | - Paddy Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States,Center for Neural Engineering, The Pennsylvania State University, State College, PA, United States,*Correspondence: Paddy Ssentongo
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Sharma R, Aashima, Nanda M, Fronterre C, Sewagudde P, Ssentongo AE, Yenney K, Arhin ND, Oh J, Amponsah-Manu F, Ssentongo P. Mapping Cancer in Africa: A Comprehensive and Comparable Characterization of 34 Cancer Types Using Estimates From GLOBOCAN 2020. Front Public Health 2022; 10:839835. [PMID: 35548083 PMCID: PMC9082420 DOI: 10.3389/fpubh.2022.839835+10.3389/fpubh.2022.839835/full#:~:text=we%20examined%20the%20burden%20of,29)%20to%20711%2c000%20in%202020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE Cancer incidence and mortality rates in Africa are increasing, yet their geographic distribution and determinants are incompletely characterized. The present study aims to establish the spatial epidemiology of cancer burden in Africa and delineate the association between cancer burden and the country-level socioeconomic status. The study also examines the forecasts of the cancer burden for 2040 and evaluates infrastructure availability across all African countries. METHODS The estimates of age, sex, and country-specific incidence and mortality of 34 neoplasms in 54 African countries, were procured from GLOBOCAN 2020. Mortality-to-incidence ratio (MIR) was employed as a proxy indicator of 5-year survival rates, and the socioeconomic development of each country was measured using its human development index (HDI). We regressed age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and MIR on HDI using linear regression model to determine the relationship between cancer burden and HDI. Maps were generated for each cancer group for each country in Africa. The data about the cancer infrastructure of African countries were extracted from the WHO Cancer Country Profiles. RESULTS In Africa, an estimated 1.1 million new cases [95% uncertainty intervals (UIs) 1.0 - 1.3 million] and 711,429 [611,604 - 827,547] deaths occurred due to neoplasms in 2020. The ASIR was estimated to be 132.1/100,000, varying from 78.4/100,000 (Niger) to 212.5/100,000 (La Réunion) in 2020. The ASMR was 88.8/100,000 in Africa, ranging from 56.6/100,000 in the Republic of the Congo to 139.4/100,000 in Zimbabwe. The MIR of all cancer combined was 0.64 in Africa, varying from 0.49 in Mauritius to 0.78 in The Gambia. HDI had a significant negative correlation with MIR of all cancer groups combined and main cancer groups (prostate, breast, cervical and colorectal). HDI explained 75% of the variation in overall 5-year cancer survival (MIR). By 2040, the burden of all neoplasms combined is forecasted to increase to 2.1 million new cases and 1.4 million deaths in Africa. CONCLUSION High cancer mortality rates in Africa demand a holistic approach toward cancer control and management, including, but not limited to, boosting cancer awareness, adopting primary and secondary prevention, mitigating risk factors, improving cancer infrastructure and timely treatment.
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Affiliation(s)
- Rajesh Sharma
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Aashima
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Mehak Nanda
- University School of Management and Entrepreneurship, Delhi Technological University, New Delhi, India
| | - Claudio Fronterre
- Centre for Health Informatics, Computing, and Statistics, Lancaster University, Lancaster, United Kingdom
| | | | - Anna E. Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States,Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | - Kelsey Yenney
- Washington State University Elson S. Floyd College of Medicine, Seattle, WA, United States
| | - Nina D. Arhin
- Division of Hematology/Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - John Oh
- Division of Trauma Surgery, Department of Surgery, Penn State College of Medicine and Milton S. Hershey Medical Center, Hershey, PA, United States
| | | | - Paddy Ssentongo
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, United States,Center for Neural Engineering, The Pennsylvania State University, State College, PA, United States,*Correspondence: Paddy Ssentongo
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Koudou GB, Monroe A, Irish SR, Humes M, Krezanoski JD, Koenker H, Malone D, Hemingway J, Krezanoski PJ. Evaluation of an accelerometer-based monitor for detecting bed net use and human entry/exit using a machine learning algorithm. Malar J 2022; 21:85. [PMID: 35279149 PMCID: PMC8917707 DOI: 10.1186/s12936-022-04102-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/23/2022] [Indexed: 11/14/2022] Open
Abstract
Background Distribution of long-lasting insecticidal bed nets (LLINs) is one of the main control strategies for malaria. Improving malaria prevention programmes requires understanding usage patterns in households receiving LLINs, but there are limits to what standard cross-sectional surveys of self-reported LLIN use can provide. This study was designed to assess the performance of an accelerometer-based approach for measuring a range of LLIN use behaviours as a proof of concept for more granular LLIN-use monitoring over longer time periods. Methods This study was carried out under controlled conditions from May to July 2018 in Liverpool, UK. A single accelerometer was affixed to the side panel of an LLIN and participants carried out five LLIN use behaviours: (1) unfurling a net; (2) entering an unfurled net; (3) lying still as if sleeping; (4) exiting from under a net; and, (5) folding up a net. The randomForest package in R, a supervised non-linear classification algorithm, was used to train models on 20-s epochs of tagged accelerometer data. Models were compared in a validation dataset using overall accuracy, sensitivity and specificity, receiver operating curves and the area under the curve (AUC). Results The five-category model had overall accuracy of 82.9% in the validation dataset, a sensitivity of 0.681 for entering a net, 0.632 for exiting, 0.733 for net down, and 0.800 for net up. A simplified four-category model, combining entering/exiting a net into one category had accuracy of 94.8%, and increased sensitivity for net down (0.756) and net up (0.829). A further simplified three-category model, identifying sleeping, net up, and a combined net down/enter/exit category had accuracy of 96.2% (483/502), with an AUC of 0.997 for net down and 0.987 for net up. Models for detecting entering/exiting by adults were significantly more accurate than for children (87.8% vs 70.0%; p < 0.001) and had a higher AUC (p = 0.03). Conclusions Understanding how LLINs are used is crucial for planning malaria prevention programmes. Accelerometer-based systems provide a promising new methodology for studying LLIN use. Further work exploring accelerometer placement, frequency of measurements and other machine learning approaches could make these methods even more accurate in the future. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04102-z.
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Tian H, Li N, Li Y, Kraemer MUG, Tan H, Liu Y, Li Y, Wang B, Wu P, Cazelles B, Lourenço J, Gao D, Sun D, Song W, Li Y, Pybus OG, Wang G, Dye C. Malaria elimination on Hainan Island despite climate change. COMMUNICATIONS MEDICINE 2022; 2:12. [PMID: 35603266 PMCID: PMC9053252 DOI: 10.1038/s43856-022-00073-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 01/11/2022] [Indexed: 11/09/2022] Open
Abstract
Background Rigorous assessment of the effect of malaria control strategies on local malaria dynamics is a complex but vital step in informing future strategies to eliminate malaria. However, the interactions between climate forcing, mass drug administration, mosquito control and their effects on the incidence of malaria remain unclear. Methods Here, we analyze the effects of interventions on the transmission dynamics of malaria (Plasmodium vivax and Plasmodium falciparum) on Hainan Island, China, controlling for environmental factors. Mathematical models were fitted to epidemiological data, including confirmed cases and population-wide blood examinations, collected between 1995 and 2010, a period when malaria control interventions were rolled out with positive outcomes. Results Prior to the massive scale-up of interventions, malaria incidence shows both interannual variability and seasonality, as well as a strong correlation with climatic patterns linked to the El Nino Southern Oscillation. Based on our mechanistic model, we find that the reduction in malaria is likely due to the large scale rollout of insecticide-treated bed nets, which reduce the infections of P. vivax and P. falciparum malaria by 93.4% and 35.5%, respectively. Mass drug administration has a greater contribution in the control of P. falciparum (54.9%) than P. vivax (5.3%). In a comparison of interventions, indoor residual spraying makes a relatively minor contribution to malaria control (1.3%–9.6%). Conclusions Although malaria transmission on Hainan Island has been exacerbated by El Nino Southern Oscillation, control methods have eliminated both P. falciparum and P. vivax malaria from this part of China. Several malaria control strategies have been implemented on Hainan Island, China, and it is important to determine which of these have been effective to guide future efforts to control malaria. Here, we use mathematical and statistical methods to assess the effectiveness of control methods using data on malaria cases on Hainan, considering the impact of climate change simultaneously, since malaria transmission is affected by the climate. We observe time-related trends in malaria incidence and a strong relationship with climate before the large-scale rollout of malaria control interventions. We find that insecticide-treated bed nets are the most effective strategy in decreasing malaria incidence, while mass drug administration and indoor residual spraying also contribute to malaria control. Our findings provide evidence that a combination of strategies reduces the burden of malaria in affected regions. Tian et al. use mathematical modelling to estimate the impact of various interventions on malaria incidence on Hainan Island, also taking into account climate change. They find that although malaria transmission has been exacerbated by climate change, insecticide-treated bed nets and other interventions were effective in controlling the disease.
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Wetzler EA, Park C, Arroz JAH, Chande M, Mussambala F, Candrinho B. Impact of mass distribution of insecticide-treated nets in Mozambique, 2012 to 2025: Estimates of child lives saved using the Lives Saved Tool. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000248. [PMID: 36962318 PMCID: PMC10022185 DOI: 10.1371/journal.pgph.0000248] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 03/22/2022] [Indexed: 11/19/2022]
Abstract
Malaria was the leading cause of post-neonatal deaths in Mozambique in 2017. The use of insecticide treated nets (ITNs) is recognized as one of the most effective ways to reduce malaria mortality in children. No previous analyses have estimated changes in mortality attributable to the scale-up of ITNs, accounting for provincial differences in mortality rates and coverage of health interventions. Based upon annual provincial ownership coverage of ITNs, the Lives Saved Tool (LiST), a multi-cause mathematical model, estimated under-5 lives saved attributable to increased household ITN coverage in 10 provinces of Mozambique between 2012 and 2018, and projected lives saved from 2019 to 2025 if 2018 coverage levels are sustained. An estimated 14,040 under-5 child deaths were averted between 2012 and 2018. If 2018 coverage levels are maintained until 2025, an additional 33,277 child deaths could be avoided. If coverage reaches at least 85% in all ten provinces by 2022, then a projected 36,063 child lives can be saved. From 2012 to 2018, the estimated number of lives saved was highest in Zambezia and Tete provinces. Increases in ITN coverage can save a substantial number of child lives in Mozambique. Without continued investment, thousands of avoidable child deaths will occur.
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Affiliation(s)
- Erica A Wetzler
- World Vision United States, Federal Way, Washington, United States of America
| | - Chulwoo Park
- Department of Public Health and Recreation, San José State University, San Jose, California, United States of America
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Stuck L, Chacky F, Festo C, Lutambi A, Abdul R, Greer G, Mandike R, Nathan R, Elisaria E, Yukich J. Evaluation of Long-Lasting Insecticidal Net Distribution Through Schools in Southern Tanzania. Health Policy Plan 2021; 37:243-254. [PMID: 34918055 DOI: 10.1093/heapol/czab140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 09/14/2021] [Accepted: 12/16/2021] [Indexed: 11/13/2022] Open
Abstract
Universal coverage with effective vector control remains the mainstay of malaria vector control in sub-Saharan Africa Tanzania has utilized a number of mechanisms for the maintenance of long-lasting insecticidal net (LLIN) coverage over time. Schools have been identified as one potential channel for continuous distribution of LLIN. This research aims to evaluate an annual school based LLIN distribution programme in Tanzania which began in 2013, called the School Net Programme (SNP). Following each of the first four rounds of SNP distribution, a household survey was conducted in intervention and comparison districts in Southern and Lake zones of Tanzania (N = 5083 households). Measures of ownership, access, and use were compared between intervention and comparison districts. Determinants of reach were assessed in intervention districts. Population access to an LLIN increased from 63.1% (95% CI: 58.8, 67.5) to 76.5% (95% CI: 72.9, 80.0) in the intervention districts between the first and last surveys. Access also rose in the comparison districts from 51.4% (95% CI: 46.9, 55.9) to 79.8% (95% CI: 77.3, 82.0) following a mass distribution and implementation of school-based distribution during the study period. LLIN use increased in intervention districts from 44.9% (95% CI: 40.5, 49.3) to 65.6% (95% CI: 59.4, 71.8) and from 57.2% (95% CI: 49.7, 64.7) to 77.4% (95% CI: 69.3, 85.5) specifically amongst primary school-aged children. Households reached by the SNP were wealthier households with children enrolled in school. The SNP in Tanzania was able to maintain population level LLIN ownership, use, and access in the absence of a mass distribution. The SNP successfully reached households which housed school-aged children. Alternative delivery strategies may need to be considered to reach households without children enrolled in school which experienced less benefit from the program.
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Affiliation(s)
- Logan Stuck
- Department of Tropical Medicine, Centre for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Frank Chacky
- National Malaria Control Programme, Dar es Salaam, Tanzania
| | | | | | | | - George Greer
- U. S. President's Malaria Initiative, United States Agency for Development, Dar es Salaam, Tanzania
| | | | - Rose Nathan
- Ifakara Health Institute, Dar es Salaam, Tanzania
| | | | - Joshua Yukich
- Department of Tropical Medicine, Centre for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, LA, USA
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Larsen DA, Church RL. Pyrethroid Resistance in Anopheles gambiae Not Associated with Insecticide-Treated Mosquito Net Effectiveness Across Sub-Saharan Africa. Am J Trop Med Hyg 2021; 105:1097-1103. [PMID: 34424859 PMCID: PMC8592134 DOI: 10.4269/ajtmh.20-0229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/20/2021] [Indexed: 11/07/2022] Open
Abstract
Pyrethroid resistance is a major concern for malaria vector control programs that predominantly rely on insecticide-treated mosquito nets (ITNs). Contradictory results of the impact of resistance have been observed during field studies. We combined continent-wide estimates of pyrethroid resistance in Anopheles gambiae from 2006 to 2017, with continent-wide survey data to assess the effect of increasing pyrethroid resistance on the effectiveness of ITNs to prevent malaria infections in sub-Saharan Africa. We used a pooled-data approach and a meta-regression of survey regions to assess how pyrethroid resistance affects the association between ITN ownership and malaria outcomes for children 6 to 59 months of age. ITN ownership reduced the risk of malaria outcomes according to both the pooled and meta-regression approaches. According to the pooled analysis, there was no observed interaction between ITN ownership and estimated level of pyrethroid resistance (likelihood ratio [LR] test, 1.127 for malaria infection confirmed by the rapid diagnostic test, P = 0.2885; LR test = 0.161 for microscopy-confirmed malaria infection, P = 0.161; LR test = 0.646 for moderate or severe anemia, P = 0.4215). Using the meta-regression approach to determine the level of pyrethroid resistance did not explain any of the variance in subnational estimates of ITN effectiveness for any of the outcomes. ITNs decreased the risk of malaria independent of the levels of pyrethroid resistance in malaria vector populations.
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Affiliation(s)
- David A. Larsen
- Syracuse University Department of Public Health, Syracuse, New York
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Omagha R, Idowu ET, Alimba CG, Otubanjo AO, Adeneye AK. Survey of ethnobotanical cocktails commonly used in the treatment of malaria in southwestern Nigeria. FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2021. [DOI: 10.1186/s43094-021-00298-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Abstract
Background
Combination of different antimalarials has become the popular method of care for malaria morbidity in conventional and traditional treatment approaches due to the need to increase the efficacy and reduce the selection of drug resistance. A worrisome concern is the critical gaps with regards to the information available on antimalarial herbal cocktails. This study presents cocktail herbal remedies in ethnomedicinal approaches to malaria treatment in Oyo and Ogun states, South West Nigeria. Ethnobotanical information on indigenous antimalarials used in combination remedies was collected from herbal practitioners using a semi-structured questionnaire.
Results
Findings showed majority of respondents treat malaria with combination herbal remedies. They sighted their beliefs and customs, the efficacy, affordability and availability of these herbs as reasons for their adoption of herbal medicines as their preferred mode of treating malaria. Enquiry revealed 26 sets of cocktail antimalarials from a variety of plant species. The plants and ingredients are extracted and used as decoction, infusion or steam baths. Oral route was the most popular mode of administration. Respondents reported they drink one to two medium-sized cups of the recipe on an average of two times daily within a duration of about 10 days.
Conclusions
Herbal antimalarial remedies continue to be the popular treatments option in our localities. This study provides knowledge of the diverse ways respondents combine medicinal herbs and other local ingredients for malaria treatment. Pharmacological screening is urgently needed to validate their safety and efficacy in order to protect the health of our locals heavily relying on them to combat high burdens of malaria.
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Thongsripong P, Hyman JM, Kapan DD, Bennett SN. Human-Mosquito Contact: A Missing Link in Our Understanding of Mosquito-Borne Disease Transmission Dynamics. ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA 2021; 114:397-414. [PMID: 34249219 PMCID: PMC8266639 DOI: 10.1093/aesa/saab011] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Indexed: 05/26/2023]
Abstract
Despite the critical role that contact between hosts and vectors, through vector bites, plays in driving vector-borne disease (VBD) transmission, transmission risk is primarily studied through the lens of vector density and overlooks host-vector contact dynamics. This review article synthesizes current knowledge of host-vector contact with an emphasis on mosquito bites. It provides a framework including biological and mathematical definitions of host-mosquito contact rate, blood-feeding rate, and per capita biting rates. We describe how contact rates vary and how this variation is influenced by mosquito and vertebrate factors. Our framework challenges a classic assumption that mosquitoes bite at a fixed rate determined by the duration of their gonotrophic cycle. We explore alternative ecological assumptions based on the functional response, blood index, forage ratio, and ideal free distribution within a mechanistic host-vector contact model. We highlight that host-vector contact is a critical parameter that integrates many factors driving disease transmission. A renewed focus on contact dynamics between hosts and vectors will contribute new insights into the mechanisms behind VBD spread and emergence that are sorely lacking. Given the framework for including contact rates as an explicit component of mathematical models of VBD, as well as different methods to study contact rates empirically to move the field forward, researchers should explicitly test contact rate models with empirical studies. Such integrative studies promise to enhance understanding of extrinsic and intrinsic factors affecting host-vector contact rates and thus are critical to understand both the mechanisms driving VBD emergence and guiding their prevention and control.
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Affiliation(s)
- Panpim Thongsripong
- Department of Microbiology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA 94118, USA
| | - James M Hyman
- Department of Mathematics, Tulane University, 6823 St. Charles Avenue, New Orleans, LA 70118, USA
| | - Durrell D Kapan
- Department of Entomology and Center for Comparative Genomics, Institute of Biodiversity Sciences and Sustainability, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA 94118, USA
- Center for Conservation and Research Training, Pacific Biosciences Research Center, University of Hawai’i at Manoa, 3050 Maile Way, Honolulu, HI 96822
| | - Shannon N Bennett
- Department of Microbiology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA 94118, USA
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Tilaye T, Tessema B, Alemu K. Malaria Infection is High at Transit and Destination Phases Among Seasonal Migrant Workers in Development Corridors of Northwest Ethiopia: A Repeated Cross-Sectional Study. Res Rep Trop Med 2021; 12:107-121. [PMID: 34079425 PMCID: PMC8165298 DOI: 10.2147/rrtm.s306001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/24/2021] [Indexed: 12/03/2022] Open
Abstract
Purpose Malaria is a leading public health problem in Ethiopia. Every year, thousands of seasonal farm workers travel to farm corridors in Northwest Ethiopia and fall at risk of malaria infection. However, the magnitude of malaria infection and risk factors during harvest time were not well identified. This study aimed at estimating the prevalence and risk factors of malaria infection among seasonal migrant workers in Northwest Ethiopia. Methods A repeated cross-sectional study was conducted at transit and destination phases in Metema district from September 15, 2018 to October 30, 2019. Data were collected using a structured questionnaire. A capillary blood sample was collected to examine infection with malaria parasite using a microscope. A multivariate logistic regression technique was used to determine risk factors. Results The malaria prevalence at transit and destination phases among migrant workers was 13.5% (95% CI: 12.07–14.93%) and 18.7% (95% CI: 16.40–21.02%), respectively. The combined prevalence was 16.1% (95% CI: 14.67–17.63%). The odds of malaria infection among migrant workers at the destination phase was 1.5 (OR=1.5, 95% CI 1.167–1.846) times higher compared to the transit phase. Education (AOR=8.198; 95% CI: 4.318–15.564), knowledge of antimalarial drugs (AOR=2.4; 95% CI: 1.43–3.95), and use of long-lasting insecticidal nets (AOR=5.0; 95% CI: 3.34–4.43) were significantly associated with malaria infection at migration phases. Conclusion This study showed that the burden of malaria among seasonal migrant workers was high at transit and destination phases. Malaria prevalence was higher at the destination phase compared to the transit phase. A tailored malaria prevention intervention is needed including awareness creation, screening, treatment, repellent, and prophylaxis at both phases to reduce malaria infections.
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Affiliation(s)
- Tesfaye Tilaye
- Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Belay Tessema
- Department of Medical Microbiology, School of Biomedical and Medical Laboratory, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Kassahun Alemu
- Department of Epidemiology and Biostatistics, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Keating J, Yukich JO, Miller JM, Scates S, Hamainza B, Eisele TP, Bennett A. Retrospective evaluation of the effectiveness of indoor residual spray with pirimiphos-methyl (Actellic) on malaria transmission in Zambia. Malar J 2021; 20:173. [PMID: 33794892 PMCID: PMC8017828 DOI: 10.1186/s12936-021-03710-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 03/24/2021] [Indexed: 11/27/2022] Open
Abstract
Background Widespread insecticide resistance to pyrethroids could thwart progress towards elimination. Recently, the World Health Organization has encouraged the use of non-pyrethroid insecticides to reduce the spread of insecticide resistance. An electronic tool for implementing and tracking coverage of IRS campaigns has recently been tested (mSpray), using satellite imagery to improve the accuracy and efficiency of the enumeration process. The purpose of this paper is to retrospectively analyse cross-sectional observational data to provide evidence of the epidemiological effectiveness of having introduced Actellic 300CS and the mSpray platform into IRS programmes across Zambia. Methods Health facility catchment areas in 40 high burden districts in 5 selected provinces were initially targeted for spraying. The mSpray platform was used in 7 districts in Luapula Province. An observational study design was used to assess the relationship between IRS exposure and confirmed malaria case incidence. A random effects Poisson model was used to quantify the effect of IRS (with and without use of the mSpray platform) on confirmed malaria case incidence over the period 2013–2017; analysis was restricted to the 4 provinces where IRS was conducted in each year 2014–2016. Results IRS was conducted in 283 health facility catchment areas from 2014 to 2016; 198 health facilities from the same provinces, that received no IRS during this period, served as a comparison. IRS appears to be associated with reduced confirmed malaria incidence; the incidence rate ratio (IRR) was lower in areas with IRS but without mSpray, compared to areas with no IRS (IRR = 0.91, 95% CI 0.84–0.98). Receiving IRS with mSpray significantly lowered confirmed case incidence (IRR = 0.75, 95% CI 0.66–0.86) compared to no IRS. IRS with mSpray resulted in lower incidence compared to IRS without mSpray (IRR = 0.83, 95% CI 0.72–0.95). Conclusions IRS using Actellic-CS appears to substantially reduce malaria incidence in Zambia. The use of the mSpray tool appears to improve the effectiveness of the IRS programme, possibly through improved population level coverage. The results of this study lend credence to the anecdotal evidence of the effectiveness of 3GIRS using Actellic, and the importance of exploring new platforms for improving effective population coverage of areas targeted for spraying.
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Affiliation(s)
- Joseph Keating
- Center for Applied Malaria Research and Evaluation, Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, 1440 Canal Street, Suite 2320, New Orleans, 70112, USA.
| | - Joshua O Yukich
- Center for Applied Malaria Research and Evaluation, Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, 1440 Canal Street, Suite 2320, New Orleans, 70112, USA
| | - John M Miller
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Elimination Centre, Chainama Hospital College Grounds, Lusaka, Zambia
| | - Sara Scates
- Center for Applied Malaria Research and Evaluation, Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, 1440 Canal Street, Suite 2320, New Orleans, 70112, USA
| | - Busiku Hamainza
- National Malaria Elimination Centre, Ministry of Health, Lusaka, Zambia
| | - Thomas P Eisele
- Center for Applied Malaria Research and Evaluation, Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, 1440 Canal Street, Suite 2320, New Orleans, 70112, USA
| | - Adam Bennett
- Global Health Sciences, University of California, San Francisco, CA, USA
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Omonijo AO, Omonijo A, Okoh HI, Ibrahim AO. Relationship between the Usage of Long-Lasting Insecticide-Treated Bed Nets (LLITNs) and Malaria Prevalence among School-Age Children in Southwestern Nigeria. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2021; 2021:8821397. [PMID: 33833812 PMCID: PMC8018844 DOI: 10.1155/2021/8821397] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/12/2021] [Accepted: 03/03/2021] [Indexed: 11/29/2022]
Abstract
Purpose The usage of LLITNs in malaria vector control has resulted in the reduction in malaria deaths among higher-risk groups (pregnant women and under-fives). However, there exists asymptomatic infection among older children, thereby making them a reservoir of malaria transmission. This study aimed at assessing the impact of LLITN usage on malaria prevalence among school-age children (SAC) in Ekiti, South Western Nigeria. Methods Cross-sectional, two-stage cluster sampling technique was used to collect data from SAC during May and June 2017. A total of 1313 (Oye LGA: 657 and Ikole LGA: 656) SAC in selected public primary schools participated in the study. Sociodemographic information as well as data on LLITN usage the previous night was obtained using pretested, semistructured questionnaires adapted from the standardized Malaria Indicator Survey (MIS) tools. Malaria infection was diagnosed by using the rapid diagnostic test (RDT) on blood samples that were collected by finger prick from each child. Data were analyzed using the Statistical Package for Social Sciences (SPSS) for Windows software version 26 (SPSS Inc., Chicago, IL, USA). Results Usage of LLITNs among SAC was significantly higher in Ikole LGA than in Oye (p < 0.001). Socioeconomic factors (access to electricity, mother's occupation, and household size) showed significant associations with LLITN usage (p < 0.001) in both Oye and Ikole LGAs. Malaria prevalence was significantly low among SAC utilizing LLITNs in both Oye and Ikole LGAs (p < 0.001). There was a significant association between gender and malaria prevalence among SAC with males having higher prevalence than females (p < 0.001). Socioeconomic factors were significantly associated with malaria prevalence in both LGAs (p < 0.001). Conclusion The usage of LLITNs caused a significant reduction in malaria prevalence among the school-age children in the study areas; hence, sensitization on usage should be scaled up towards malaria elimination.
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Affiliation(s)
| | - Adetunji Omonijo
- Department of Family Medicine, Federal Teaching Hospital, Ido Ekiti, Ekiti State, Nigeria
| | - Hillary Iwegbunem Okoh
- Department of Animal and Environmental Biology, Federal University Oye Ekiti State, Oye Ekiti, Nigeria
| | - Azeez Oyemomi Ibrahim
- Department of Family Medicine, Federal Teaching Hospital, Ido Ekiti, Ekiti State, Nigeria
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Aïkpon R, Affoukou C, Hounpkatin B, Eclou DD, Cyaka Y, Egwu E, Agbessi N, Tokponnon F, Salifou S, Salami L, Hounto AO. Digitalized mass distribution campaign of insecticide-treated nets (ITNs) in the particular context of Covid-19 pandemic in Benin: challenges and lessons learned. Malar J 2020; 19:431. [PMID: 33239004 PMCID: PMC7686833 DOI: 10.1186/s12936-020-03508-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 11/18/2020] [Indexed: 11/17/2022] Open
Abstract
Background In 2020, Benin has implemented a digitalized mass distribution campaign of insecticide-treated nets (ITNs) in the particular context of COVID-19 pandemic. This paper describes the implementation process as well as the challenges and lessons learned from this campaign. Methods A descriptive design was used for reporting the planning and implementation process of ITNs campaign. Moreover, the changes and adaptations related to COVID-19 pandemic are described. Results A total of 3,175,773 households were registered corresponding to a total of 14,423,998 persons (13.55% more from projection). Moreover, 94.16% (13,581,637 people) of enumerated population were protected. A total of 7,652,166 ITNs were distributed countrywide. Conclusions High political commitment, engagement and support add to the financial and technical supports from partners were the essential factors that make 2020 ITNs mass campaign success in Benin despite the particular context of COVID-19 pandemic. It is essential to maintain the prevention activities for malaria and this could substantially reduce the overall impact of the COVID-19 pandemic for the populations at malaria risk.
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Affiliation(s)
- Rock Aïkpon
- Programme Nationale de Lutte Contre Le Paludisme (PNLP), Cotonou, Benin.
| | - Cyriaque Affoukou
- Programme Nationale de Lutte Contre Le Paludisme (PNLP), Cotonou, Benin
| | | | | | - Yves Cyaka
- Alliance for Malaria Prevention, Geneva, Switzerland
| | | | - Narcisse Agbessi
- Programme Nationale de Lutte Contre Le Paludisme (PNLP), Cotonou, Benin
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Rossi P, Villar P. Private health investments under competing risks: Evidence from malaria control in Senegal. JOURNAL OF HEALTH ECONOMICS 2020; 73:102330. [PMID: 32711291 DOI: 10.1016/j.jhealeco.2020.102330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 04/09/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
This study exploits the introduction of high subsidies for anti-malaria products in Senegal in 2009 to investigate whether malaria prevents parents from investing in child health. A simple model of health investments under competing mortality risks predicts that private expenses to fight malaria and other diseases should increase in response to anti-malaria public interventions. We test and validate this prediction using original panel data from a household expenditure survey combined with geographical information on malaria prevalence. We find that health expenditures in malarious regions catch up with non-malarious regions. The same result holds for parental health-seeking behavior against other diseases like diarrhea. These patterns cannot be explained by differential trends between regions. Our results suggest that behavioral responses to anti-malaria campaigns magnify their impact on all-cause mortality for children.
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Affiliation(s)
- Pauline Rossi
- University of Amsterdam, office E6.21, Roeterstraat 11, 1018WB Amsterdam, Netherlands.
| | - Paola Villar
- University of Namur (UNamur), CRED, office 633, Remparts de la Vierge 8, 5000 Namur, Belgium.
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Ashton RA, Joseph V, van den Hoogen LL, Tetteh KKA, Stresman G, Worges M, Druetz T, Chang MA, Rogier E, Lemoine JF, Drakeley C, Eisele TP. Risk Factors for Malaria Infection and Seropositivity in the Elimination Area of Grand'Anse, Haiti: A Case-Control Study among Febrile Individuals Seeking Treatment at Public Health Facilities. Am J Trop Med Hyg 2020; 103:767-777. [PMID: 32458784 PMCID: PMC7410432 DOI: 10.4269/ajtmh.20-0097] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The island of Hispaniola aims to eliminate malaria by 2025; however, there are limited data to describe epidemiologic risk factors for malaria in this setting. A prospective case–control study was conducted at four health facilities in southwest Haiti, aiming to describe factors influencing the risk of current and past malaria infection. Cases were defined as individuals attending facilities with current or recent fever and positive malaria rapid diagnostic test (RDT), while controls were those with current or recent fever and RDT negative. Serological markers of recent and cumulative exposure to Plasmodium were assessed using the multiplex bead assay from dried blood spots and used for alternate case definitions. Kuldorff’s spatial scan statistic was used to identify local clusters of infection or exposure. Logistic regression models were used to assess potential risk factors for RDT positivity and recent exposure markers, including age-group, gender, and recruiting health facility as group-matching variables. A total of 192 cases (RDT positive) and 915 controls (RDT negative) were recruited. Consistent spatial clusters were identified for all three infection and exposure metrics, indicating temporal stability of malaria transmission at these sites. Risk factors included remoteness from health facilities and household construction, furthermore, insecticide-treated net ownership or use was associated with reduced odds of RDT positivity. These findings indicate the malaria risk in Grand’Anse is driven primarily by location. Travel, occupation, and other behavioral factors were not associated with malaria. These data can support the National Malaria Program to refine and target their intervention approaches, and to move toward elimination.
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Affiliation(s)
- Ruth A Ashton
- Center for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Vena Joseph
- Center for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Lotus L van den Hoogen
- Center for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Kevin K A Tetteh
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Gillian Stresman
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matt Worges
- Center for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Thomas Druetz
- Department of Social and Preventive Medicine, University of Montreal School of Public Health, Montreal, Canada.,Center for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Michelle A Chang
- Division of Parasitic Diseases and Malaria, Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Eric Rogier
- Division of Parasitic Diseases and Malaria, Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Jean Frantz Lemoine
- Programme National de Contrôle de la Malaria, Ministry of Public Health and Population, Port-au-Prince, Haiti
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Thomas P Eisele
- Center for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana
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Systematic review and meta-analysis of the cost and cost-effectiveness of distributing insecticide-treated nets for the prevention of malaria. Acta Trop 2020; 202:105229. [PMID: 31669182 DOI: 10.1016/j.actatropica.2019.105229] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/21/2019] [Accepted: 10/21/2019] [Indexed: 11/20/2022]
Abstract
Insecticide-treated nets are one of two core vector control interventions recommended by the World Health Organization for deployment in malaria-endemic regions around the world, especially sub-Saharan Africa. Although there are many factors that influence the type of distribution strategy chosen, among the most important considerations for the type of distribution strategy chosen is cost, both in terms of total expenditure required and in terms of relative cost-effectiveness. This research attempted to inform these decisions by conducting a systematic review and meta-analysis of the literature on the cost and cost-effectiveness of ITN distribution. The analysis compared the relative cost and cost-effectiveness of distribution strategies. Findings suggest that mass campaigns have lower average distribution costs per net compared with continuous/health facility distribution or sale/vouchers, although the relationship between distribution channel and cost were not statistically significant in the multivariate regression models. Continuous/health facility distribution channels were found to be more cost-effective than mass campaigns for averting DALYs, death, and cases of malaria. Those who design and budget for malaria programs should base decisions about distribution channels more on operational and epidemiological considerations than on cost per net, as the costs per net between distribution channels are not statistically different.
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Aïkpon RY, Padonou G, Dagnon F, Ossè R, Ogouyemi Hounto A, Tokponon F, Aïkpon G, Lyikirenga L, Akogbéto M. Upsurge of malaria transmission after indoor residual spraying withdrawal in Atacora region in Benin, West Africa. Malar J 2020; 19:3. [PMID: 31900182 PMCID: PMC6942255 DOI: 10.1186/s12936-019-3086-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 12/21/2019] [Indexed: 11/23/2022] Open
Abstract
Background In Benin, malaria vector control mostly relies on long-lasting, insecticidal-treated bed nets (LLINs) and indoor residual spraying (IRS) operations. From 2011 to 2016, an IRS programme has been implemented in Atacora region. However, in 2017 the programme was withdrawn from two other regions in the northern part of the country, with hopes that gains would be relatively sustained because of the seasonality of malaria transmission. What would be the vulnerability of populations to malaria after the withdrawal of IRS? Methods Monthly mosquito collections were performed through human landing captures (HLCs) for 24 months (from January to December 2016 during the last IRS campaign, and from January to December 2018, 2 years after the withdrawal of IRS). Vector mosquitoes biting density was sampled by HLC and was tested for presence of Plasmodium falciparum sporozoites. The carcass of these mosquitoes (abdomens, wing, legs) were subjected to molecular species identification using polymerase chain reaction (PCR) assays. Results It is noticed a drastic increase (~ 3 times higher) of vector abundance after the withdrawal of IRS. Mosquito biting rates in the 3 survey districts increased significantly after IRS was withdrawn. In 2018, after IRS cessation a significant increase of entomological inoculation rate was recorded, where each inhabitant received an average of 94.9 infected bites/year to 129.21 infected bites/year against an average of 17.15 infected bites/year to 24.82 infected bites/year in 2016. Conclusion It is obvious that the withdrawal of IRS confers a vulnerability of the population with regard to the malaria transmission. Robust monitoring is needed to better understand when and where IRS should be most adequate, or can be safely withdrawn. In case of withdrawal, adapted accompanying measures should be proposed according to the context not only to maintain the gains capitalized with IRS, but also to avoid any rebound of transmission.
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Affiliation(s)
- Rock Yves Aïkpon
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Benin. .,Ecole Normale Supérieure de Natitingou (ENS), Natitingou, Benin. .,Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), Abomey, Benin.
| | - Gil Padonou
- Ecole Normale Supérieure de Natitingou (ENS), Natitingou, Benin.,Université d'Abomey-Calavi, Cotonou, Benin
| | - Fortuné Dagnon
- US President's Malaria Initiative, US Agency for International Development, Cotonou, Benin
| | - Razaki Ossè
- Ecole Normale Supérieure de Natitingou (ENS), Natitingou, Benin.,Université Nationale d'Agriculture (UNA), Ketou, Benin
| | - Aurore Ogouyemi Hounto
- Faculté des Sciences de la Santé (FSS), Cotonou, Benin.,Programme National de Lutte Contre le Paludisme, Cotonou, Benin
| | | | | | | | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Benin
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Malede A, Aemero M, Gari SR, Kloos H, Alemu K. Barriers of persistent long-lasting insecticidal nets utilization in villages around Lake Tana, Northwest Ethiopia: a qualitative study. BMC Public Health 2019; 19:1303. [PMID: 31619208 PMCID: PMC6796332 DOI: 10.1186/s12889-019-7692-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/25/2019] [Indexed: 11/10/2022] Open
Abstract
Background Malaria remains a major public health problem in Ethiopia. The use of LLINs is an effective approach to reducing transmission. Persistent use of LLINs is determined by numerous factors. Quantitative studies have assessed LLIN ownership and utilization, but the behavioral, socio-cultural, socioeconomic and net distribution contexts that impact their use have not been examined in depth. This study aimed to explore barriers of persistent LLIN use among communities around Lake Tana. Methods Twenty-three community residents who owned LLINs (15) or not (8) during the study period and 38 key informants were interviewed from April to June 2017. Phenomenological study was employed to explore the local contexts and factors that influence persistent use of LLINs. Individuals were purposefully selected to capture different views. Community residents were selected based on their permanent residence and LLIN use experience. Key informants were health extension workers, local leaders, students, and health professionals. The data were managed using QSR International NVivo Version 10 software and coded, and themes were identified. Results Killing ability of nets against arthropods other than mosquitoes reportedly made use of LLINs a favored malaria prevention method despite their ineffectiveness after 3 months. Conical nets were preferred due to their compatibility with varied sleeping structures. Numerous factors influenced persistent use, notably erroneous perceptions about LLINs, malaria and mosquitoes; bedbug infestation; inconvenience; unintended uses; distribution problem of nets; and socio-cultural and economic factors. Unintended uses were often associated with local needs and seldom linked with social issues and deficiencies in information about malaria and LLINs. Collateral benefits were considered important, principally in terms of disinfestation of bedbugs. Conclusions Non-persistent LLIN use was associated with inconvenient bed net design and early damage; non-potency of the insecticide against other arthropods; facilitation of bedbug infestation; unintended uses; wrong perceptions about malaria, mosquitoes, and LLINs; and inadequate follow-up regarding LLINs utilization. Distribution of conical nets and provision of adequate information on LLINs and malaria may promote persistent use. Using an insecticide that also kills arthropods other than mosquitoes may reduce unintended uses and increase persistent use.
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Affiliation(s)
- Asmamaw Malede
- Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Mulugeta Aemero
- Department of Medical Parasitology, School of Biomedical & Laboratory Sciences, University of Gondar, Gondar, Ethiopia
| | - Sirak Robele Gari
- Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia
| | - Helmut Kloos
- Department of Epidemiology and Biostatistics, University of California, San Francisco, USA
| | - Kassahun Alemu
- Department of Epidemiology and Biostatistics, Institute of Public Health, University of Gondar, Gondar, Ethiopia
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Kweka EJ, Tungu PK, Mahande AM, Mazigo HD, Sayumwe S, Msangi S, Lyaruu L, Waweru J, Kisinza W, Wangai J. Bio-efficacy and wash resistance of MAGNet long-lasting insecticidal net against wild populations of Anopheles funestus in experimental huts in Muheza, Tanzania. Malar J 2019; 18:335. [PMID: 31570107 PMCID: PMC6771101 DOI: 10.1186/s12936-019-2973-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 09/24/2019] [Indexed: 11/30/2022] Open
Abstract
Background The decline in malaria cases and vectors is major milestone in fighting against malaria. The efficacy of MAGNet long-lasting insecticidal nets (MAGNet LLIN), an alpha-cypermethrin incorporated long-lasting net, with the target dose ± 25% of 5.8 g active ingredient (AI)/kg (4.35–7.25 g AI/kg) was evaluated in six veranda-trap experimental huts in Muheza, Tanzania against freely flying wild population of Anopheles funestus. Methods MAGNet LLINs were tested against wild, free-flying, host-seeking An. funestus mosquitoes over a period of 6 weeks (total of 36 nights in the huts). MAGNet LLIN efficacy was determined in terms of mosquito mortality, blood-feeding inhibition, deterrence, induced exiting, personal protection, and insecticidal killing over 20 washes according to WHO standardized procedures. Efficacy was compared with reference to a WHOPES recommended approved LLINs (DuraNet) and to a net conventionally treated (CTN) treated with alpha-cypermethrin at WHO-recommended dose and washed to just before cut-off point. The efficacy of MAGNet was evaluated in experimental huts against wild, free-flying, pyrethroid-resistant An. funestus. The WHO-susceptibility method was used to detect resistance in wild Anopheles exposed to 0.75% permethrin. Mosquito mortality, blood-feeding inhibition and personal protection were compared between untreated nets and standard LLINs. Blood-feeding rates were recorded and compared between the 20 times washed; blood-feeding rates between 20 times washed MAGNet LLIN and 20 times washed WHOPES-approved piperonyl butoxide (PBO)/pyrethroid were not statistically different (p > 0.05). Results The results have evidently shown that MAGNet LLIN provides similar blood-feeding inhibition, exophily, mortality, and deterrence to the standard approved LLIN, thus meeting the WHOPES criteria for blood feeding. The significantly high feeding inhibition and personal protection over pyrethroid-resistant An. funestus recorded by both unwashed and 20 times washed MAGNet compared to the unwashed DuraNet, the WHOPES-approved standard pyrethroid-only LLIN provides proof of MAGNet meeting Phase II WHOPES criteria for a LLIN. Conclusion Based on this study, MAGNet has been shown to have a promising impact on protection when 20 times washed against a highly resistant population of An. funestus.
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Affiliation(s)
- Eliningaya J Kweka
- Department of Medical Parasitology and Entomology, School of Medicine, Catholic University of Health and Allied Sciences, P.O. Box 1464, Mwanza, Tanzania. .,Mosquito Section, Division of Livestock and Human Health Disease Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania.
| | - Patrick K Tungu
- Amani Medical Research Centre, National Institute for Medical Research, P.O.Box 81, Muheza, Tanga, Tanzania
| | - Aneth M Mahande
- Division of Livestock and Human Health Disease Vector Control, Tropical Pesticides Research Institute, Mabogini Field Station, Moshi, Tanzania
| | - Humphrey D Mazigo
- Mosquito Section, Division of Livestock and Human Health Disease Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Subira Sayumwe
- Mosquito Section, Division of Livestock and Human Health Disease Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Shandala Msangi
- Department of Medical Parasitology and Entomology, School of Medicine, Catholic University of Health and Allied Sciences, P.O. Box 1464, Mwanza, Tanzania
| | - Lucile Lyaruu
- Mosquito Section, Division of Livestock and Human Health Disease Vector Control, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - John Waweru
- PestNet Kenya Ltd, P.O. BOX 51533-00200, Nairobi, Kenya
| | - William Kisinza
- Amani Medical Research Centre, National Institute for Medical Research, P.O.Box 81, Muheza, Tanga, Tanzania
| | - James Wangai
- PestNet Kenya Ltd, P.O. BOX 51533-00200, Nairobi, Kenya
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Krezanoski P, Haberer J. Objective monitoring of mosquito bednet usage and the ethical challenge of respecting study bystanders' privacy. Clin Trials 2019; 16:466-468. [PMID: 31368779 PMCID: PMC10561128 DOI: 10.1177/1740774519865525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Insecticide-treated bednets are among the most prevalent and cost-effective tools for preventing malaria throughout the world. Consistent bednet use is crucial for effectiveness, but assessing adherence is challenging due to limitations in current measurement tools. Recent technologies have introduced methods for remote electronic bednet use monitoring. While valuable for researchers, these monitoring tools create potential ethical concerns for study bystanders because the monitors are typically unable to discriminate between individuals who are or are not study participants. Considerations related to study bystanders, including privacy, ancillary care obligations, and community perceptions, are discussed.
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Millogo O, Doamba JEO, Sié A, Utzinger J, Vounatsou P. Geographical variation in the association of child, maternal and household health interventions with under-five mortality in Burkina Faso. PLoS One 2019; 14:e0218163. [PMID: 31260473 PMCID: PMC6602179 DOI: 10.1371/journal.pone.0218163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 05/28/2019] [Indexed: 11/18/2022] Open
Abstract
Background Over the past 15 years, scaling up of cost effective interventions resulted in a remarkable decline of under-five mortality rates (U5MR) in sub-Saharan Africa. However, the reduction shows considerable heterogeneity. We estimated the association of child, maternal, and household interventions with U5MR in Burkina Faso at national and subnational levels and identified the regions with least effective interventions. Methods Data on health-related interventions and U5MR were extracted from the Burkina Faso Demographic and Health Survey (DHS) 2010. Bayesian geostatistical proportional hazards models with a Weibull baseline hazard were fitted on the mortality outcome. Spatially varying coefficients were considered to assess the geographical variation in the association of the health interventions with U5MR. The analyses were adjusted for child, maternal, and household characteristics, as well as climatic and environmental factors. Findings The average U5MR was as high as 128 per 1000 ranging from 81 (region of Centre-Est) to 223 (region of Sahel). At national level, DPT3 immunization and baby post-natal check within 24 hours after birth had the most important association with U5MR (hazard rates ratio (HRR) = 0.89, 95% Bayesian credible interval (BCI): 0.86–0.98 and HRR = 0.89, 95% BCI: 0.86–0.92, respectively). At sub-national level, the most effective interventions are the skilled birth attendance, and improved drinking water, followed by baby post-natal check within 24 hours after birth, vitamin A supplementation, antenatal care visit and all-antigens immunization (including BCG, Polio3, DPT3, and measles immunization). Centre-Est, Sahel, and Sud-Ouest were the regions with the highest number of effective interventions. There was no intervention that had a statistically important association with child survival in the region of Hauts Bassins. Interpretation The geographical variation in the magnitude and statistical importance of the association between health interventions and U5MR raises the need to deliver and reinforce health interventions at a more granular level. Priority interventions are DPT3 immunization, skilled birth attendance, baby post-natal visits in the regions of Sud-Ouest, Sahel, and Hauts Bassins, respectively. Our methodology could be applied to other national surveys, as it allows an incisive, data-driven and specific decision-making approach to optimize the allocation of health interventions at subnational level.
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Affiliation(s)
- Ourohiré Millogo
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Centre de Recherche en Santé de Nouna, Nouna, Burkina Faso
| | | | - Ali Sié
- Centre de Recherche en Santé de Nouna, Nouna, Burkina Faso
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Penelope Vounatsou
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Dolan CB, BenYishay A, Grépin KA, Tanner JC, Kimmel AD, Wheeler DC, McCord GC. The impact of an insecticide treated bednet campaign on all-cause child mortality: A geospatial impact evaluation from the Democratic Republic of Congo. PLoS One 2019; 14:e0212890. [PMID: 30794694 PMCID: PMC6386397 DOI: 10.1371/journal.pone.0212890] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 02/11/2019] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To test the impact of a nationwide Long-Lasting Insecticidal Nets [LLINs] distribution program in the Democratic Republic of Congo [DRC] on all-cause under-five child mortality exploiting subnational variation in malaria endemicity and the timing in the scale-up of the program across provinces. DESIGN Geospatial Impact Evaluation using a difference-in-differences approach. SETTING Democratic Republic of the Congo. PARTICIPANTS 52,656 children sampled in the 2007 and 2013/2014 DRC Demographic and Health Surveys. INTERVENTIONS The analysis provides plausibly causal estimates of both average treatment effects of the LLIN distribution campaign and geospatial heterogeneity in these effects based on malaria endemicity. It compares the under-five, all-cause mortality for children pre- and post-LLIN campaign relative to children in those areas that had not yet been exposed to the campaign using a difference-in-differences model and controlling for year- and province-fixed effects, and province-level trends in mortality. RESULTS We find that the campaign led to a 41% decline [3.7 percentage points, 95% CI 1.3 to 6.0] in under-5 mortality risk among children living in rural areas with malaria ecology above the sample median. Results were robust to controlling for household assets and the presence of other health aid programs. No effect was detected in children living in areas with malaria ecology below the median. CONCLUSION The findings of this paper make important contributions to the evidence base for the effectiveness of large scale-national LLIN campaigns against malaria. We found that the program was effective in areas of the DRC with the highest underlying risk of malaria. Targeting bednets to areas with greatest underlying risk for malaria may help to increase the efficiency of increasingly limited malaria resources but should be balanced against other malaria control concerns.
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Affiliation(s)
- Carrie B. Dolan
- Department of Kinesiology and Health Sciences, William and Mary, Williamsburg, Virginia, United States of America
| | - Ariel BenYishay
- Department of Economics, William and Mary, Williamsburg, Virginia, United States of America
| | - Karen A. Grépin
- Department of Health Sciences, Wilfrid Laurier University, Waterloo, Ontario, Canada
| | - Jeffery C. Tanner
- Independent Evaluation Group, World Bank, Washington, DC, United States of America
| | - April D. Kimmel
- Health Behavior and Policy, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - David C. Wheeler
- Department of Biostatistics, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Gordon C. McCord
- School of Global Policy and Strategy, University of California San Diego, San Diego, California, United States of America
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Strengthening long-lasting insecticidal nets effectiveness monitoring using retrospective analysis of cross-sectional, population-based surveys across sub-Saharan Africa. Sci Rep 2018; 8:17110. [PMID: 30459359 PMCID: PMC6244007 DOI: 10.1038/s41598-018-35353-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 10/25/2018] [Indexed: 02/01/2023] Open
Abstract
Bed nets averted 68% of malaria cases in Africa between 2000 and 2015. However, concerns over insecticide resistance, bed net durability and the effectiveness of long-lasting insecticidal nets (LLIN) are growing. To assess the effectiveness of LLINs of different ages and insecticides against malaria, we conducted a population-based, cross-sectional study using data from 162,963 children younger than 5 years of age participating in 33 Demographic and Health and Malaria Indicator Surveys conducted in 21 countries between 2009 and 2016. We used Bayesian logistic regression to estimate associations between LLIN age, insecticide type, and malaria. Children sleeping under LLINs the previous night experienced 21% lower odds of malaria infection than children who did not (odds ratio [OR] 0.79; 95% Uncertainty Interval [UI] 0.76-0.82). Nets less than one year of age exhibited the strongest protective effect (OR 0.75; 95% UI 0.72-0.79), and protection weakened as net age increased. LLINs containing different insecticides exhibited similar protection (ORdeltamethrin 0.78 [0.75-0.82]; ORpermethrin 0.79 [0.75-0.83]; ORalphacypermethrin 0.85 [0.76-0.94]). Freely-available, population-based surveys can enhance and guide current entomological monitoring amid concerns of insecticide resistance and bed net durability, and be used with locally-collected data to support decisions on LLIN redistribution campaign timing which insecticide to use.
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Mahande AM, Msangi S, Lyaruu LJ, Kweka EJ. Bio-efficacy of DuraNet® long-lasting insecticidal nets against wild populations of Anopheles arabiensis in experimental huts. Trop Med Health 2018; 46:36. [PMID: 30410416 PMCID: PMC6219078 DOI: 10.1186/s41182-018-0118-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 10/23/2018] [Indexed: 11/21/2022] Open
Abstract
Background Mosquitoes have developed resistance to multiple classes of insecticides for malaria vector control. A new generation of long-lasting insecticidal bed nets (LLINs) has been developed with increased efficacy against these resistant mosquitoes. The present study therefore evaluated the efficacy of the pyrethroid-based LLINs, DuraNet versus PermaNet 3.0, in an Eastern Africa hut design in Magugu in northern Tanzania where mosquitoes’ population higher proportion (69.3%) has been identified as Anopheles gambiae s.l. Methods Standard World Health Organization bioefficacy evaluations were conducted in both laboratory and experimental huts. Experimental hut evaluations were conducted in an area with high populations of Anopheles arabiensis. All nets used were subjected to laboratory cone bioassays and then to experimental hut trials. Mosquito mortality, blood-feeding inhibition, and personal protection rate were compared between untreated nets, unwashed LN, and LN that were washed 20 times. Results Standard WHO laboratory bioefficacy evaluations of DuraNet and PermaNet® 3.0 which were untreated, washed, or 20 times washed showed optimal knockdown and mortality for both net types against a susceptible strain of An. arabiensis. In standard experimental hut evaluations, the blood feeding inhibition for PermaNet® 3.0 unwashed and washed was 82.4% (76.3–88.6%) to 91.5% (84.1–98.8%) while for DuraNet was 98.3% (97.0–99.5%) to 96.0% (94.1–88.2%) respectively. The DuraNet LLINs showed a significantly higher killing effect than the other treatment of 90.0% (86.1–94.2%) and 94.0% (90.2–97.9%) for unwashed and washed nets respectively. No significant difference in deterrence or induced exophily was detected between the treatment arms. There were no adverse effects reported among sleepers in the experimental huts. Conclusion The findings of this study indicate that the pyrethroid-based net DuraNet LLINs attained required efficacy when evaluated against wild population of An. arabiensis from Northern Tanzania. This adds value to the existing vector control tool box which gives community wider choice for vector control.
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Affiliation(s)
- Aneth M Mahande
- 1Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute, Mabogini Field Station, Moshi, Tanzania
| | - Shandala Msangi
- 2Division of Livestock and Human Diseases Vector Control, Mosquito Section, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Lucile J Lyaruu
- 2Division of Livestock and Human Diseases Vector Control, Mosquito Section, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania
| | - Eliningaya J Kweka
- 2Division of Livestock and Human Diseases Vector Control, Mosquito Section, Tropical Pesticides Research Institute, P.O. Box 3024, Arusha, Tanzania.,3Department of Medical Parasitology and Entomology, School of Medicine, Catholic University of Health and Allied Sciences, P.O. Box 1464, Mwanza, Tanzania
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Tiono AB, Ouédraogo A, Ouattara D, Bougouma EC, Coulibaly S, Diarra A, Faragher B, Guelbeogo MW, Grisales N, Ouédraogo IN, Ouédraogo ZA, Pinder M, Sanon S, Smith T, Vanobberghen F, Sagnon N, Ranson H, Lindsay SW. Efficacy of Olyset Duo, a bednet containing pyriproxyfen and permethrin, versus a permethrin-only net against clinical malaria in an area with highly pyrethroid-resistant vectors in rural Burkina Faso: a cluster-randomised controlled trial. Lancet 2018; 392:569-580. [PMID: 30104047 DOI: 10.1016/s0140-6736(18)31711-2] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 07/16/2018] [Accepted: 07/19/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Substantial reductions in malaria incidence in sub-Saharan Africa have been achieved with massive deployment of long-lasting insecticidal nets (LLINs), but pyrethroid resistance threatens control. Burkina Faso is an area with intense malaria transmission and highly pyrethroid-resistant vectors. We assessed the effectiveness of bednets containing permethrin, a pyrethroid, and pyriproxyfen, an insect growth regulator, versus permethrin-only (standard) LLINs against clinical malaria in children younger than 5 years in Banfora, Burkina Faso. METHODS In this two-group, step-wedge, cluster-randomised, controlled, superiority trial, standard LLINs were incrementally replaced with LLINs treated with permethrin plus pyriproxyfen (PPF) in 40 rural clusters in Burkina Faso. In each cluster, 50 children (aged 6 months to 5 years) were followed up by passive case detection for clinical malaria. Cross-sectional surveys were done at the start and the end of the transmission seasons in 2014 and 2015. We did monthly collections from indoor light traps to estimate vector densities. Primary endpoints were the incidence of clinical malaria, measured by passive case detection, and the entomological inoculation rate. Analyses were adjusted for clustering and for month and health centre. This trial is registered as ISRCTN21853394. FINDINGS 1980 children were enrolled in the cohort in 2014 and 2157 in 2015. At the end of the study, more than 99% of children slept under a bednet. The incidence of clinical malaria was 2·0 episodes per child-year in the standard LLIN group and 1·5 episodes per child-year in the PPF-treated LLIN group (incidence rate ratio 0·88 [95% CI 0·77-0·99; p=0·04]). The entomological inoculation rate was 85 (95% CI 63-108) infective bites per transmission season in the standard LLIN group versus 42 (32-52) infective bites per transmission season in the PPF-treated LLIN group (rate ratio 0·49, 95% CI 0·32-0·66; p<0·0001). INTERPRETATION PPF-treated LLINs provide greater protection against clinical malaria than do standard LLINs and could be used as an alternative to standard LLINs in areas with intense transmission of Plasmodium falciparum malaria and highly pyrethroid-resistant vectors. FUNDING EU Seventh Framework Programme.
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Affiliation(s)
- Alfred B Tiono
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Alphonse Ouédraogo
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Daouda Ouattara
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Edith C Bougouma
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Sam Coulibaly
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Amidou Diarra
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | | | - Moussa W Guelbeogo
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | | | - Issa N Ouédraogo
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | | | | | - Souleymane Sanon
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Tom Smith
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Fiona Vanobberghen
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - N'Fale Sagnon
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Hilary Ranson
- Liverpool School of Tropical Medicine, Liverpool, UK
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Hailu T, Alemu M, Mulu W, Abera B. Incidence of Plasmodium infections and determinant factors among febrile children in a district of Northwest Ethiopia; a cross-sectional study. TROPICAL DISEASES TRAVEL MEDICINE AND VACCINES 2018; 4:8. [PMID: 30116548 PMCID: PMC6086041 DOI: 10.1186/s40794-018-0069-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 08/05/2018] [Indexed: 11/10/2022]
Abstract
Background According to the Ethiopian national malaria indicator survey of 2015, the highest burden of Plasmodia infection resided among the school-age children. Even though several studies revealed various determinant factors of childhood malaria, consistent findings are not reported across the nation and elsewhere. This in turn creates obstacles in implementing exactprevention and control measures in the study area in particular and the country at large. Objectives The aim of this study is to determine the incidence of Plasmodium and determinant factors among febrile children in Northwest Ethiopia. Methods This cross-sectional study was conducted from April–August 2016. Blood samples were collected from febrile children selected by systematic random sampling. Thin and thick blood films were prepared and stained with Giemsa. Statistical analysis was done via SPSS version 20 statistical software and data were summarized with percentages and frequencies. The bi-variate and multi-variate logistic regressions were used to measure strength of association between Plasmodium infection and determinant factors, and to rule out confounders, respectively. Result Among a total of 333 febrile children, 146 (43.8%) were positive for the Plasmodia. The prevalence of plasmodium infection was 47%, 50%, and 40%, among the age groups of 6–8, 9–10 and 11–14 years, respectively. Prevalence of plasmodium among male and female children was 44.2% and 43.5%, respectively. Shorter distance from stagnant water (AOR (adjusted odds ratio) =43, 95% CI (confidence interval):2.8–680.7; P < 0.01), family size (AOR =14.7, 95% CI:(1.4–151.2; P = 0.02), outdoor sleeping (AOR =36.6, 95% CI:2.4–554.2; P < 0.01, irregular bed net use (AOR =21.1, 95% CI:2.9–154.7; P < 0.01), and late bed time (AOR =31.9, 95% CI:2.8–371.3; P < 0.01) showed statistically significant association with plasmodium infection. Conclusion The incidence of Plasmodium infection is high among febrile children in the study area. Shorter distance from stagnant water, larger family size, outdoor sleeping, irregular bed net use, and late night sleeping are the major determinant factors for the high incidence of malaria. Therefore, community mobilization and health education should focus on the specific determinant factors of plasmodium infection to alleviate incidence of malaria among the school children.
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Affiliation(s)
- Tadesse Hailu
- Department of Medical Microbiology, Immunology and Parasitology, Bahir Dar University, PO Box 79, Bahir Dar, Ethiopia
| | - Megbaru Alemu
- Department of Medical Microbiology, Immunology and Parasitology, Bahir Dar University, PO Box 79, Bahir Dar, Ethiopia
| | - Wondemagegn Mulu
- Department of Medical Microbiology, Immunology and Parasitology, Bahir Dar University, PO Box 79, Bahir Dar, Ethiopia
| | - Bayeh Abera
- Department of Medical Microbiology, Immunology and Parasitology, Bahir Dar University, PO Box 79, Bahir Dar, Ethiopia
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Stuck L, Lutambi A, Chacky F, Schaettle P, Kramer K, Mandike R, Nathan R, Yukich J. Can school-based distribution be used to maintain coverage of long-lasting insecticide treated bed nets: evidence from a large scale programme in southern Tanzania? Health Policy Plan 2018; 32:980-989. [PMID: 28444184 DOI: 10.1093/heapol/czx028] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2017] [Indexed: 11/13/2022] Open
Abstract
Many sub-Saharan African countries have achieved substantial gains in insecticide treated bednet coverage since 2005. The Tanzania National Malaria Control Programme identified school-based net distribution as one potential 'keep-up' strategy for the purpose of maintaining long-lasting insecticidal net (LLIN) coverage after a nationwide mass campaign in 2011. The School Net Programme (SNP) was implemented in three regions of southern Tanzania and distributed one LLIN to each enrolled child attending schools in primary grades (standards) 1, 3, 5 and 7, and secondary grades (forms) 2 and 4 in 2013 and again with slightly modified eligibility criteria in 2014 and 2015. Household surveys in the programme area as well as in a control area were conducted after each of the SNP distributions to measure ownership and use of long-lasting insecticide treated nets. Ownership of at least one LLIN after the first distribution was 76.1% (95% CI 70.8-80.7) in the intervention area and 78.6% (95% CI 74.4-82.3) in the control area. After the second distribution, ownership of at least one LLIN had dropped significantly in the control area to 65.4% (95% CI 59.5-71.0) in 2015 (P < 0.001), while coverage in the intervention area was maintained at 79.3% (95% CI 75.4 × 82.6). Ownership of at least one LLIN in intervention area remained stable following the second round of net distribution. During the same period LLIN ownership, especially of enough nets to ensure all household member access, fell significantly in the control area. These results demonstrate that the SNP may be sufficient to maintain stable LLIN coverage following a mass distribution of LLINs.
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Affiliation(s)
- Logan Stuck
- Department of Tropical Medicine, Centre for Applied Malaria Research and Evaluation, Tulane School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | | | - Frank Chacky
- National Malaria Control Programme, Dar es Salaam, Tanzania
| | - Paul Schaettle
- Department of Global Community Health and Behavioral Sciences, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Karen Kramer
- National Malaria Control Programme and Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Renata Mandike
- National Malaria Control Programme, Dar es Salaam, Tanzania
| | - Rose Nathan
- Ifakara Health Institute, Dar es Salaam, Tanzania
| | - Joshua Yukich
- Department of Tropical Medicine, center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
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Tizifa TA, Kabaghe AN, McCann RS, van den Berg H, Van Vugt M, Phiri KS. Prevention Efforts for Malaria. CURRENT TROPICAL MEDICINE REPORTS 2018; 5:41-50. [PMID: 29629252 PMCID: PMC5879044 DOI: 10.1007/s40475-018-0133-y] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE OF REVIEW Malaria remains a global burden contributing to morbidity and mortality especially in children under 5 years of age. Despite the progress achieved towards malaria burden reduction, achieving elimination in more countries remains a challenge. This article aims to review the prevention and control strategies for malaria, to assess their impact towards reducing the disease burden and to highlight the best practices observed. RECENT FINDINGS Use of long-lasting insecticide-treated nets and indoor residual spraying has resulted a decline in the incidence and prevalence of malaria in Sub-Saharan Africa. Other strategies such as larval source management have been shown to reduce mosquito density but require further evaluation. New methods under development such as house improvement have demonstrated to minimize disease burden but require further evidence on efficacy. Development of the RTS,S/AS01 malaria vaccine that provides protection in under-five children has provided further progress in efforts of malaria control. SUMMARY There has been a tremendous reduction in malaria burden in the past decade; however, more work is required to fill the necessary gaps to eliminate malaria.
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Affiliation(s)
- Tinashe A. Tizifa
- Training and Research Unit of Excellence (TRUE), Public Health Department, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Alinune N. Kabaghe
- Training and Research Unit of Excellence (TRUE), Public Health Department, College of Medicine, University of Malawi, Blantyre, Malawi
- Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Robert S. McCann
- Training and Research Unit of Excellence (TRUE), Public Health Department, College of Medicine, University of Malawi, Blantyre, Malawi
- Wageningen University and Research Center, Wageningen, Netherlands
| | | | - Michele Van Vugt
- Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Kamija S. Phiri
- Training and Research Unit of Excellence (TRUE), Public Health Department, College of Medicine, University of Malawi, Blantyre, Malawi
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Cohen RL, Murray J, Jack S, Arscott-Mills S, Verardi V. Impact of multisectoral health determinants on child mortality 1980-2010: An analysis by country baseline mortality. PLoS One 2017; 12:e0188762. [PMID: 29211765 PMCID: PMC5718556 DOI: 10.1371/journal.pone.0188762] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/30/2017] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Some health determinants require relatively stronger health system capacity and socioeconomic development than others to impact child mortality. Few quantitative analyses have analyzed how the impact of health determinants varies by mortality level. METHODS 149 low- and middle-income countries were stratified into high, moderate, low, and very low baseline levels of child mortality in 1990. Data for 52 health determinants were collected for these countries for 1980-2010. To quantify how changes in health determinants were associated with mortality decline, univariable and multivariable regression models were constructed. An advanced statistical technique that is new for child mortality analyses-MM-estimation with first differences and country clustering-controlled for outliers, fixed effects, and variation across decades. FINDINGS Some health determinants (immunizations, education) were consistently associated with child mortality reduction across all mortality levels. Others (staff availability, skilled birth attendance, fertility, water and sanitation) were associated with child mortality reduction mainly in low or very low mortality settings. The findings indicate that the impact of some health determinants on child mortality was only apparent with stronger health systems, public infrastructure and levels of socioeconomic development, whereas the impact of other determinants was apparent at all stages of development. Multisectoral progress was essential to mortality reduction at all baseline mortality levels. CONCLUSION Policy-makers can use such analyses to direct investments in health and non-health sectors and to set five-year child mortality targets appropriate for their baseline mortality levels and local context.
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Affiliation(s)
- Robert L. Cohen
- United States Agency for International Development, Washington, DC, United States of America
| | - John Murray
- Independent Consultant, Iowa City, Iowa, United States of America
| | - Susan Jack
- University of Otago, Dunedin, New Zealand
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Raghavendra K, Chourasia MK, Swain DK, Bhatt RM, Uragayala S, Dutta GDP, Kleinschmidt I. Monitoring of long-lasting insecticidal nets (LLINs) coverage versus utilization: a community-based survey in malaria endemic villages of Central India. Malar J 2017; 16:467. [PMID: 29149892 PMCID: PMC5693530 DOI: 10.1186/s12936-017-2117-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 11/11/2017] [Indexed: 11/10/2022] Open
Abstract
Background Despite the known effectiveness of long-lasting insecticidal nets (LLINs) in providing protection against malaria, high level of ownership and use are very difficult to achieve and maintain. Nearly 40,000 LLINs were distributed in 2014 as an intervention tool against malaria transmission in 80 villages of Keshkal sub-district in Chhattisgarh, India. This study assessed LLIN coverage, access, utilization pattern, and key determinants for the net use 1 year after mass distribution. Methods In 2015, a cross-sectional household survey was carried out in 80 study clusters (whole village or part of village). From each cluster, 40 households were randomly selected and interviewed using a structured questionnaire adapted from the malaria indicator survey of Roll Back Malaria guidelines. Information on demographic characteristics, LLIN ownership, and its use on the night before the survey, and physical condition of LLINs were recorded. Results 2970 households were interviewed with a total of 15,003 individuals present in the households during the night before the survey. Nearly 98% of households had at least one LLIN and 59.4% of the surveyed population reportedly used an LLIN the previous night. LLIN use varied from 41 to 94% between the study clusters. Nearly 89% of the LLINs were found in good physical condition (without holes). However, proportion of household with at least one LLIN per two persons was only 39%. Conclusion Universal coverage of LLINs was inadequate in the study clusters making it difficult for all household members to use an LLIN. LLIN use varied between clusters and was highest in children under 5 years of age. Health education campaigns and creating awareness about the benefit of sleeping under the LLINs in providing protection against malaria is required not only to high risk groups of pregnant women and children below 5 years of age but all the members of the family to have an epidemiological impact of this intervention at the community level. Relatively high net use despite poor access to LLINs indicates an overall desire to use nets when they are available. The main barrier to increased use of nets is the low coverage at household level.
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Affiliation(s)
- Kamaraju Raghavendra
- National Institute of Malaria Research (ICMR), Sector-8, Dwarka, New Delhi, 110077, India.
| | - Mehul Kumar Chourasia
- National Institute of Malaria Research (ICMR) IIR-WHO Project, Field Unit, Kondagaon, Chhattisgarh, India
| | - Dipak Kumar Swain
- National Institute of Malaria Research (ICMR) IIR-WHO Project, Field Unit, Kondagaon, Chhattisgarh, India
| | - Rajendra M Bhatt
- National Institute of Malaria Research (ICMR), Field Unit, Lalpur, Raipur, Chhattisgarh, India
| | - Sreehari Uragayala
- National Institute of Malaria Research (ICMR), Field Unit, Bangalore, Karnataka, India
| | - G D P Dutta
- National Institute of Malaria Research (ICMR), Field Unit, Lalpur, Raipur, Chhattisgarh, India
| | - Immo Kleinschmidt
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
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Kesteman T, Randrianarivelojosia M, Rogier C. The protective effectiveness of control interventions for malaria prevention: a systematic review of the literature. F1000Res 2017; 6:1932. [PMID: 29259767 PMCID: PMC5721947 DOI: 10.12688/f1000research.12952.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/27/2017] [Indexed: 12/22/2022] Open
Abstract
Background: Thanks to a considerable increase in funding, malaria control interventions (MCI) whose efficacy had been demonstrated by controlled trials have been largely scaled up during the last decade. Nevertheless, it was not systematically investigated whether this efficacy had been preserved once deployed on the field. Therefore, we sought the literature to assess the disparities between efficacy and effectiveness and the effort to measure the protective effectiveness (PE) of MCI. Methods: The PubMed database was searched for references with keywords related to malaria, to control interventions for prevention and to study designs that allow for the measure of the PE against parasitemia or against clinical outcomes. Results: Our search retrieved 1423 references, and 162 articles were included in the review. Publications were scarce before the year 2000 but dramatically increased afterwards. Bed nets was the MCI most studied (82.1%). The study design most used was a cross-sectional study (65.4%). Two thirds (67.3%) were conducted at the district level or below, and the majority (56.8%) included only children even if the MCI didn’t target only children. Not all studies demonstrated a significant PE from exposure to MCI: 60.6% of studies evaluating bed nets, 50.0% of those evaluating indoor residual spraying, and 4/8 showed an added PE of using both interventions as compared with one only; this proportion was 62.5% for intermittent preventive treatment of pregnant women, and 20.0% for domestic use of insecticides. Conclusions: This review identified numerous local findings of low, non-significant PE –or even the absence of a protective effect provided by these MCIs. The identification of such failures in the effectiveness of MCIs advocates for the investigation of the causes of the problem found. Ideal evaluations of the PE of MCIs should incorporate both a large representativeness and an evaluation of the PE stratified by subpopulations.
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Affiliation(s)
- Thomas Kesteman
- Fondation Mérieux, Lyon, France.,Malaria Research Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | | | - Christophe Rogier
- Malaria Research Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar.,Ecole doctorale Sciences de la vie et de l'environnement, Université d'Antananarivo, Antananarivo, Madagascar.,Institute for Biomedical Research of the French Armed Forces (IRBA), Brétigny-Sur-Orge , France.,Unité de recherche sur les maladies infectieuses et tropicales émergentes - (URMITE), Marseille, France
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Florey LS, Bennett A, Hershey CL, Bhattarai A, Nielsen CF, Ali D, Luhanga M, Taylor C, Eisele TP, Yé Y. Impact of Insecticide-Treated Net Ownership on All-Cause Child Mortality in Malawi, 2006-2010. Am J Trop Med Hyg 2017; 97:65-75. [PMID: 28990922 PMCID: PMC5619930 DOI: 10.4269/ajtmh.15-0929] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Insecticide-treated nets (ITNs) have been shown to be highly effective at reducing malaria morbidity and mortality in children. However, there are limited studies that assess the association between increasing ITN coverage and child mortality over time, at the national level, and under programmatic conditions. Two analytic approaches were used to examine this association: a retrospective cohort analysis of individual children and a district-level ecologic analysis. To evaluate the association between household ITN ownership and all-cause child mortality (ACCM) at the individual level, data from the 2010 Demographic and Health Survey (DHS) were modeled in a Cox proportional hazards framework while controlling for numerous environmental, household, and individual confounders through the use of exact matching. To evaluate population-level association between ITN ownership and ACCM between 2006 and 2010, program ITN distribution data and mortality data from the 2006 Multiple Indicator Cluster Survey and the 2010 DHS were aggregated at the district level and modeled using negative binomial regression. In the Cox model controlling for household, child and maternal health factors, children between 1 and 59 months in households owning an ITN had significantly lower mortality compared with those without an ITN (hazard ratio = 0.75, 95% confidence interval [CI] = 0.62–90). In the district-level model, higher ITN ownership was significantly associated with lower ACCM (incidence rate ratio = 0.77; 95% CI = 0.60–0.98). These findings suggest that increasing ITN ownership may have contributed to the decline in ACCM during 2006–2010 in Malawi and represent a novel use of district-level data from nationally representative surveys.
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Affiliation(s)
| | - Adam Bennett
- Malaria Elimination Initiative, University of California, San Francisco, California
| | - Christine L Hershey
- President's Malaria Initiative, United States Agency for International Development, Arlington, Virginia
| | - Achuyt Bhattarai
- President's Malaria Initiative, Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Carrie F Nielsen
- President's Malaria Initiative, Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Doreen Ali
- National Malaria Control Programme, Ministry of Health, Lilongwe, Malawi
| | - Misheck Luhanga
- National Malaria Control Programme, Ministry of Health, Lilongwe, Malawi
| | | | - Thomas P Eisele
- Center for Applied Malaria Research and Evaluation, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
| | - Yazoume Yé
- ICF, MEASURE Evaluation, Rockville, Maryland
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Wang H, Abajobir AA, Abate KH, Abbafati C, Abbas KM, Abd-Allah F, Abera SF, Abraha HN, Abu-Raddad LJ, Abu-Rmeileh NME, Adedeji IA, Adedoyin RA, Adetifa IMO, Adetokunboh O, Afshin A, Aggarwal R, Agrawal A, Agrawal S, Ahmad Kiadaliri A, Ahmed MB, Aichour MTE, Aichour AN, Aichour I, Aiyar S, Akanda AS, Akinyemiju TF, Akseer N, Al Lami FH, Alabed S, Alahdab F, Al-Aly Z, Alam K, Alam N, Alasfoor D, Aldridge RW, Alene KA, Al-Eyadhy A, Alhabib S, Ali R, Alizadeh-Navaei R, Aljunid SM, Alkaabi JM, Alkerwi A, Alla F, Allam SD, Allebeck P, Al-Raddadi R, Alsharif U, Altirkawi KA, Alvis-Guzman N, Amare AT, Ameh EA, Amini E, Ammar W, Amoako YA, Anber N, Andrei CL, Androudi S, Ansari H, Ansha MG, Antonio CAT, Anwari P, Ärnlöv J, Arora M, Artaman A, Aryal KK, Asayesh H, Asgedom SW, Asghar RJ, Assadi R, Assaye AM, Atey TM, Atre SR, Avila-Burgos L, Avokpaho EFGA, Awasthi A, Babalola TK, Bacha U, Badawi A, Balakrishnan K, Balalla S, Barac A, Barber RM, Barboza MA, Barker-Collo SL, Bärnighausen T, Barquera S, Barregard L, Barrero LH, Baune BT, Bazargan-Hejazi S, Bedi N, Beghi E, Béjot Y, Bekele BB, Bell ML, Bello AK, Bennett DA, Bennett JR, Bensenor IM, Benson J, Berhane A, Berhe DF, Bernabé E, Beuran M, Beyene AS, Bhala N, Bhansali A, Bhaumik S, Bhutta ZA, Bicer BK, Bidgoli HH, Bikbov B, Birungi C, Biryukov S, Bisanzio D, Bizuayehu HM, Bjerregaard P, Blosser CD, Boneya DJ, Boufous S, Bourne RRA, Brazinova A, Breitborde NJK, Brenner H, Brugha TS, Bukhman G, Bulto LNB, Bumgarner BR, Burch M, Butt ZA, Cahill LE, Cahuana-Hurtado L, Campos-Nonato IR, Car J, Car M, Cárdenas R, Carpenter DO, Carrero JJ, Carter A, Castañeda-Orjuela CA, Castro FF, Castro RE, Catalá-López F, Chen H, Chiang PPC, Chibalabala M, Chisumpa VH, Chitheer AA, Choi JYJ, Christensen H, Christopher DJ, Ciobanu LG, Cirillo M, Cohen AJ, Colquhoun SM, Coresh J, Criqui MH, Cromwell EA, Crump JA, Dandona L, Dandona R, Dargan PI, das Neves J, Davey G, Davitoiu DV, Davletov K, de Courten B, De Leo D, Degenhardt L, Deiparine S, Dellavalle RP, Deribe K, Deribew A, Des Jarlais DC, Dey S, Dharmaratne SD, Dherani MK, Diaz-Torné C, Ding EL, Dixit P, Djalalinia S, Do HP, Doku DT, Donnelly CA, dos Santos KPB, Douwes-Schultz D, Driscoll TR, Duan L, Dubey M, Duncan BB, Dwivedi LK, Ebrahimi H, El Bcheraoui C, Ellingsen CL, Enayati A, Endries AY, Ermakov SP, Eshetie S, Eshrati B, Eskandarieh S, Esteghamati A, Estep K, Fanuel FBB, Faro A, Farvid MS, Farzadfar F, Feigin VL, Fereshtehnejad SM, Fernandes JG, Fernandes JC, Feyissa TR, Filip I, Fischer F, Foigt N, Foreman KJ, Frank T, Franklin RC, Fraser M, Friedman J, Frostad JJ, Fullman N, Fürst T, Furtado JM, Futran ND, Gakidou E, Gambashidze K, Gamkrelidze A, Gankpé FG, Garcia-Basteiro AL, Gebregergs GB, Gebrehiwot TT, Gebrekidan KG, Gebremichael MW, Gelaye AA, Geleijnse JM, Gemechu BL, Gemechu KS, Genova-Maleras R, Gesesew HA, Gething PW, Gibney KB, Gill PS, Gillum RF, Giref AZ, Girma BW, Giussani G, Goenka S, Gomez B, Gona PN, Gopalani SV, Goulart AC, Graetz N, Gugnani HC, Gupta PC, Gupta R, Gupta R, Gupta T, Gupta V, Haagsma JA, Hafezi-Nejad N, Hakuzimana A, Halasa YA, Hamadeh RR, Hambisa MT, Hamidi S, Hammami M, Hancock J, Handal AJ, Hankey GJ, Hao Y, Harb HL, Hareri HA, Harikrishnan S, Haro JM, Hassanvand MS, Havmoeller R, Hay RJ, Hay SI, He F, Heredia-Pi IB, Herteliu C, Hilawe EH, Hoek HW, Horita N, Hosgood HD, Hostiuc S, Hotez PJ, Hoy DG, Hsairi M, Htet AS, Hu G, Huang JJ, Huang H, Iburg KM, Igumbor EU, Ileanu BV, Inoue M, Irenso AA, Irvine CMS, Islam SMS, Islam N, Jacobsen KH, Jaenisch T, Jahanmehr N, Jakovljevic MB, Javanbakht M, Jayatilleke AU, Jeemon P, Jensen PN, Jha V, Jin Y, John D, John O, Johnson SC, Jonas JB, Jürisson M, Kabir Z, Kadel R, Kahsay A, Kalkonde Y, Kamal R, Kan H, Karch A, Karema CK, Karimi SM, Karthikeyan G, Kasaeian A, Kassaw NA, Kassebaum NJ, Kastor A, Katikireddi SV, Kaul A, Kawakami N, Kazanjan K, Keiyoro PN, Kelbore SG, Kemp AH, Kengne AP, Keren A, Kereselidze M, Kesavachandran CN, Ketema EB, Khader YS, Khalil IA, Khan EA, Khan G, Khang YH, Khera S, Khoja ATA, Khosravi MH, Kibret GD, Kieling C, Kim YJ, Kim CI, Kim D, Kim P, Kim S, Kimokoti RW, Kinfu Y, Kishawi S, Kissoon N, Kivimaki M, Knudsen AK, Kokubo Y, Kopec JA, Kosen S, Koul PA, Koyanagi A, Kravchenko M, Krohn KJ, Kuate Defo B, Kuipers EJ, Kulikoff XR, Kulkarni VS, Kumar GA, Kumar P, Kumsa FA, Kutz M, Lachat C, Lagat AK, Lager ACJ, Lal DK, Lalloo R, Lambert N, Lan Q, Lansingh VC, Larson HJ, Larsson A, Laryea DO, Lavados PM, Laxmaiah A, Lee PH, Leigh J, Leung J, Leung R, Levi M, Li Y, Liao Y, Liben ML, Lim SS, Linn S, Lipshultz SE, Liu S, Lodha R, Logroscino G, Lorch SA, Lorkowski S, Lotufo PA, Lozano R, Lunevicius R, Lyons RA, Ma S, Macarayan ER, Machado IE, Mackay MT, Magdy Abd El Razek M, Magis-Rodriguez C, Mahdavi M, Majdan M, Majdzadeh R, Majeed A, Malekzadeh R, Malhotra R, Malta DC, Mantovani LG, Manyazewal T, Mapoma CC, Marczak LB, Marks GB, Martin EA, Martinez-Raga J, Martins-Melo FR, Massano J, Maulik PK, Mayosi BM, Mazidi M, McAlinden C, McGarvey ST, McGrath JJ, McKee M, Mehata S, Mehndiratta MM, Mehta KM, Meier T, Mekonnen TC, Meles KG, Memiah P, Memish ZA, Mendoza W, Mengesha MM, Mengistie MA, Mengistu DT, Menon GR, Menota BG, Mensah GA, Meretoja TJ, Meretoja A, Mezgebe HB, Micha R, Mikesell J, Miller TR, Mills EJ, Minnig S, Mirarefin M, Mirrakhimov EM, Misganaw A, Mishra SR, Mohammad KA, Mohammadi A, Mohammed KE, Mohammed S, Mohan MBV, Mohanty SK, Mokdad AH, Mollenkopf SK, Molokhia M, Monasta L, Montañez Hernandez JC, Montico M, Mooney MD, Moore AR, Moradi-Lakeh M, Moraga P, Morawska L, Mori R, Morrison SD, Mruts KB, Mueller UO, Mullany E, Muller K, Murthy GVS, Murthy S, Musa KI, Nachega JB, Nagata C, Nagel G, Naghavi M, Naidoo KS, Nanda L, Nangia V, Nascimento BR, Natarajan G, Negoi I, Nguyen CT, Nguyen QL, Nguyen TH, Nguyen G, Ningrum DNA, Nisar MI, Nomura M, Nong VM, Norheim OF, Norrving B, Noubiap JJN, Nyakarahuka L, O'Donnell MJ, Obermeyer CM, Ogbo FA, Oh IH, Okoro A, Oladimeji O, Olagunju AT, Olusanya BO, Olusanya JO, Oren E, Ortiz A, Osgood-Zimmerman A, Ota E, Owolabi MO, Oyekale AS, PA M, Pacella RE, Pakhale S, Pana A, Panda BK, Panda-Jonas S, Park EK, Parsaeian M, Patel T, Patten SB, Patton GC, Paudel D, Pereira DM, Perez-Padilla R, Perez-Ruiz F, Perico N, Pervaiz A, Pesudovs K, Peterson CB, Petri WA, Petzold M, Phillips MR, Piel FB, Pigott DM, Pishgar F, Plass D, Polinder S, Popova S, Postma MJ, Poulton RG, Pourmalek F, Prasad N, Purwar M, Qorbani M, Quintanilla BPA, Rabiee RHS, Radfar A, Rafay A, Rahimi-Movaghar A, Rahimi-Movaghar V, Rahman MHU, Rahman SU, Rahman M, Rai RK, Rajsic S, Ram U, Rana SM, Ranabhat CL, Rao PV, Rawaf S, Ray SE, Rego MAS, Rehm J, Reiner RC, Remuzzi G, Renzaho AMN, Resnikoff S, Rezaei S, Rezai MS, Ribeiro AL, Rivas JC, Rokni MB, Ronfani L, Roshandel G, Roth GA, Rothenbacher D, Roy A, Rubagotti E, Ruhago GM, Saadat S, Sabde YD, Sachdev PS, Sadat N, Safdarian M, Safi S, Safiri S, Sagar R, Sahathevan R, Sahebkar A, Sahraian MA, Salama J, Salamati P, Salomon JA, Salvi SS, Samy AM, Sanabria JR, Sanchez-Niño MD, Santos IS, Santric Milicevic MM, Sarmiento-Suarez R, Sartorius B, Satpathy M, Sawhney M, Saxena S, Saylan MI, Schmidt MI, Schneider IJC, Schulhofer-Wohl S, Schutte AE, Schwebel DC, Schwendicke F, Seedat S, Seid AM, Sepanlou SG, Servan-Mori EE, Shackelford KA, Shaheen A, Shahraz S, Shaikh MA, Shamsipour M, Shamsizadeh M, Sharma J, Sharma R, She J, Shen J, Shetty BP, Shi P, Shibuya K, Shifa GT, Shigematsu M, Shiri R, Shiue I, Shrime MG, Sigfusdottir ID, Silberberg DH, Silpakit N, Silva DAS, Silva JP, Silveira DGA, Sindi S, Singh JA, Singh PK, Singh A, Singh V, Sinha DN, Skarbek KAK, Skiadaresi E, Sligar A, Smith DL, Sobaih BHA, Sobngwi E, Soneji S, Soriano JB, Sreeramareddy CT, Srinivasan V, Stathopoulou V, Steel N, Stein DJ, Steiner C, Stöckl H, Stokes MA, Strong M, Sufiyan MB, Suliankatchi RA, Sunguya BF, Sur PJ, Swaminathan S, Sykes BL, Szoeke CEI, Tabarés-Seisdedos R, Tadakamadla SK, Tadese F, Tandon N, Tanne D, Tarajia M, Tavakkoli M, Taveira N, Tehrani-Banihashemi A, Tekelab T, Tekle DY, Temsah MH, Terkawi AS, Tesema CL, Tesssema B, Theis A, Thomas N, Thompson AH, Thomson AJ, Thrift AG, Tiruye TY, Tobe-Gai R, Tonelli M, Topor-Madry R, Topouzis F, Tortajada M, Tran BX, Truelsen T, Trujillo U, Tsilimparis N, Tuem KB, Tuzcu EM, Tyrovolas S, Ukwaja KN, Undurraga EA, Uthman OA, Uzochukwu BSC, van Boven JFM, Varakin YY, Varughese S, Vasankari T, Vasconcelos AMN, Velasquez IM, Venketasubramanian N, Vidavalur R, Violante FS, Vishnu A, Vladimirov SK, Vlassov VV, Vollset SE, Vos T, Waid JL, Wakayo T, Wang YP, Weichenthal S, Weiderpass E, Weintraub RG, Werdecker A, Wesana J, Wijeratne T, Wilkinson JD, Wiysonge CS, Woldeyes BG, Wolfe CDA, Workicho A, Workie SB, Xavier D, Xu G, Yaghoubi M, Yakob B, Yalew AZ, Yan LL, Yano Y, Yaseri M, Ye P, Yimam HH, Yip P, Yirsaw BD, Yonemoto N, Yoon SJ, Yotebieng M, Younis MZ, Zaidi Z, Zaki MES, Zeeb H, Zenebe ZM, Zerfu TA, Zhang AL, Zhang X, Zodpey S, Zuhlke LJ, Lopez AD, Murray CJL. Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970-2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet 2017; 390:1084-1150. [PMID: 28919115 PMCID: PMC5605514 DOI: 10.1016/s0140-6736(17)31833-0] [Citation(s) in RCA: 488] [Impact Index Per Article: 69.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 05/21/2017] [Accepted: 06/07/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016. METHODS We have evaluated how well civil registration systems captured deaths using a set of demographic methods called death distribution methods for adults and from consideration of survey and census data for children younger than 5 years. We generated an overall assessment of completeness of registration of deaths by dividing registered deaths in each location-year by our estimate of all-age deaths generated from our overall estimation process. For 163 locations, including subnational units in countries with a population greater than 200 million with complete vital registration (VR) systems, our estimates were largely driven by the observed data, with corrections for small fluctuations in numbers and estimation for recent years where there were lags in data reporting (lags were variable by location, generally between 1 year and 6 years). For other locations, we took advantage of different data sources available to measure under-5 mortality rates (U5MR) using complete birth histories, summary birth histories, and incomplete VR with adjustments; we measured adult mortality rate (the probability of death in individuals aged 15-60 years) using adjusted incomplete VR, sibling histories, and household death recall. We used the U5MR and adult mortality rate, together with crude death rate due to HIV in the GBD model life table system, to estimate age-specific and sex-specific death rates for each location-year. Using various international databases, we identified fatal discontinuities, which we defined as increases in the death rate of more than one death per million, resulting from conflict and terrorism, natural disasters, major transport or technological accidents, and a subset of epidemic infectious diseases; these were added to estimates in the relevant years. In 47 countries with an identified peak adult prevalence for HIV/AIDS of more than 0·5% and where VR systems were less than 65% complete, we informed our estimates of age-sex-specific mortality using the Estimation and Projection Package (EPP)-Spectrum model fitted to national HIV/AIDS prevalence surveys and antenatal clinic serosurveillance systems. We estimated stillbirths, early neonatal, late neonatal, and childhood mortality using both survey and VR data in spatiotemporal Gaussian process regression models. We estimated abridged life tables for all location-years using age-specific death rates. We grouped locations into development quintiles based on the Socio-demographic Index (SDI) and analysed mortality trends by quintile. Using spline regression, we estimated the expected mortality rate for each age-sex group as a function of SDI. We identified countries with higher life expectancy than expected by comparing observed life expectancy to anticipated life expectancy on the basis of development status alone. FINDINGS Completeness in the registration of deaths increased from 28% in 1970 to a peak of 45% in 2013; completeness was lower after 2013 because of lags in reporting. Total deaths in children younger than 5 years decreased from 1970 to 2016, and slower decreases occurred at ages 5-24 years. By contrast, numbers of adult deaths increased in each 5-year age bracket above the age of 25 years. The distribution of annualised rates of change in age-specific mortality rate differed over the period 2000 to 2016 compared with earlier decades: increasing annualised rates of change were less frequent, although rising annualised rates of change still occurred in some locations, particularly for adolescent and younger adult age groups. Rates of stillbirths and under-5 mortality both decreased globally from 1970. Evidence for global convergence of death rates was mixed; although the absolute difference between age-standardised death rates narrowed between countries at the lowest and highest levels of SDI, the ratio of these death rates-a measure of relative inequality-increased slightly. There was a strong shift between 1970 and 2016 toward higher life expectancy, most noticeably at higher levels of SDI. Among countries with populations greater than 1 million in 2016, life expectancy at birth was highest for women in Japan, at 86·9 years (95% UI 86·7-87·2), and for men in Singapore, at 81·3 years (78·8-83·7) in 2016. Male life expectancy was generally lower than female life expectancy between 1970 and 2016, and the gap between male and female life expectancy increased with progression to higher levels of SDI. Some countries with exceptional health performance in 1990 in terms of the difference in observed to expected life expectancy at birth had slower progress on the same measure in 2016. INTERPRETATION Globally, mortality rates have decreased across all age groups over the past five decades, with the largest improvements occurring among children younger than 5 years. However, at the national level, considerable heterogeneity remains in terms of both level and rate of changes in age-specific mortality; increases in mortality for certain age groups occurred in some locations. We found evidence that the absolute gap between countries in age-specific death rates has declined, although the relative gap for some age-sex groups increased. Countries that now lead in terms of having higher observed life expectancy than that expected on the basis of development alone, or locations that have either increased this advantage or rapidly decreased the deficit from expected levels, could provide insight into the means to accelerate progress in nations where progress has stalled. FUNDING Bill & Melinda Gates Foundation, and the National Institute on Aging and the National Institute of Mental Health of the National Institutes of Health.
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Ferreira CP, Lyra SP, Azevedo F, Greenhalgh D, Massad E. Modelling the impact of the long-term use of insecticide-treated bed nets on Anopheles mosquito biting time. Malar J 2017; 16:373. [PMID: 28915892 PMCID: PMC5602891 DOI: 10.1186/s12936-017-2014-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 09/04/2017] [Indexed: 11/24/2022] Open
Abstract
Background Evidence of changing in biting and resting behaviour of the main malaria vectors has been mounting up in recent years as a result of selective pressure by the widespread and long-term use of insecticide-treated bed nets (ITNs), and indoor residual spraying. The impact of resistance behaviour on malaria intervention efficacy has important implications for the epidemiology and malaria control programmes. In this context, a theoretical framework is presented to understand the mechanisms determining the evolution of feeding behaviour under the pressure of use of ITNs. Methods An agent-based stochastic model simulates the impact of insecticide-treated bed nets on mosquito fitness by reducing the biting rates, as well as increasing mortality rates. The model also incorporates a heritability function that provides the necessary genetic plasticity upon which natural selection would act to maximize the fitness under the pressure of the control strategy. Results The asymptotic equilibrium distribution of mosquito population versus biting time is shown for several daily uses of ITNs, and the expected disruptive selection on this mosquito trait is observed in the simulations. The relative fitness of strains that bite at much earlier time with respect to the wild strains, when a threshold of about 50% of ITNs coverage highlights the hypothesis of a behaviour selection. A sensitivity analysis has shown that the top three parameters that play a dominant role on the mosquito fitness are the proportion of individuals using bed nets and its effectiveness, the impact of bed nets on mosquito oviposition, and the mosquito genetic plasticity related to changing in biting time. Conclusion By taking the evolutionary aspect into account, the model was able to show that the long-term use of ITNs, although representing an undisputed success in reducing malaria incidence and mortality in many affected areas, is not free of undesirable side effects. From the evolutionary point of view of the parasite virulence, it should be expected that plasmodium parasites would be under pressure to reduce their virulence. This speculative hypothesis can eventually be demonstrated in the medium to long-term use of ITNs.
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Affiliation(s)
- Claudia P Ferreira
- Departamento de Bioestatística, IBB, UNESP, Botucatu, SP, 18618-689, Brazil
| | - Silas P Lyra
- Departamento de Bioestatística, IBB, UNESP, Botucatu, SP, 18618-689, Brazil
| | - Franciane Azevedo
- Faculdade de Computação e Engenharia Elétrica, UNIFESSPA, Marabá, PA, 68507-590, Brazil
| | - David Greenhalgh
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow, G1 1XH, Scotland
| | - Eduardo Massad
- School of Medicine, University of São Paulo, São Paulo, SP, 01246-903, Brazil.
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Ogola E, Villinger J, Mabuka D, Omondi D, Orindi B, Mutunga J, Owino V, Masiga DK. Composition of Anopheles mosquitoes, their blood-meal hosts, and Plasmodium falciparum infection rates in three islands with disparate bed net coverage in Lake Victoria, Kenya. Malar J 2017; 16:360. [PMID: 28886724 PMCID: PMC5591540 DOI: 10.1186/s12936-017-2015-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 09/04/2017] [Indexed: 11/10/2022] Open
Abstract
Background Small islands serve as potential malaria reservoirs through which new infections might come to the mainland and may be important targets in malaria elimination efforts. This study investigated malaria vector species diversity, blood-meal hosts, Plasmodium infection rates, and long-lasting insecticidal net (LLIN) coverage on Mageta, Magare and Ngodhe Islands of Lake Victoria in western Kenya, a region where extensive vector control is implemented on the mainland. Results From trapping for six consecutive nights per month (November 2012 to March 2015) using CDC light traps, pyrethrum spray catches and backpack aspiration, 1868 Anopheles mosquitoes were collected. Based on their cytochrome oxidase I (COI) and intergenic spacer region PCR and sequencing, Anopheles gambiae s.l. (68.52%), Anopheles coustani (19.81%) and Anopheles funestus s.l. (11.67%) mosquitoes were differentiated. The mean abundance of Anopheles mosquitoes per building per trap was significantly higher (p < 0.001) in Mageta than in Magare and Ngodhe. Mageta was also the most populated island (n = 6487) with low LLIN coverage of 62.35% compared to Ngodhe (n = 484; 88.31%) and Magare (n = 250; 98.59%). Overall, 416 (22.27%) engorged Anopheles mosquitoes were analysed, of which 41 tested positive for Plasmodium falciparum infection by high-resolution melting (HRM) analysis of 18S rRNA and cytochrome b PCR products. Plasmodium falciparum infection rates were 10.00, 11.76, 0, and 18.75% among blood-fed An. gambiae s.s. (n = 320), Anopheles arabiensis (n = 51), An. funestus s.s. (n = 29), and An. coustani (n = 16), respectively. Based on HRM analysis of vertebrate cytochrome b, 16S rRNA and COI PCR products, humans (72.36%) were the prominent blood-meal hosts of malaria vectors, but 20.91% of blood-meals were from non-human vertebrate hosts. Conclusions These findings demonstrate high Plasmodium infection rates among the primary malaria vectors An. gambiae s.s. and An. arabiensis, as well as in An. coustani for the first time in the region, and that non-human blood-meal sources play an important role in their ecology. Further, the higher Anopheles mosquito abundances on the only low LLIN coverage island of Mageta suggests that high LLIN coverage has been effective in reducing malaria vector populations on Magare and Ngodhe Islands.
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Affiliation(s)
- Edwin Ogola
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.,Department of Biochemistry and Molecular Biology, Egerton University Njoro Campus, P.O. Box 536, Egerton, 20115, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.
| | - Danspaid Mabuka
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya
| | - David Omondi
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.,Department of Biochemistry and Molecular Biology, Egerton University Njoro Campus, P.O. Box 536, Egerton, 20115, Kenya
| | - Benedict Orindi
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya
| | - James Mutunga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya
| | - Vincent Owino
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya.,Department of Biochemistry and Molecular Biology, Egerton University Njoro Campus, P.O. Box 536, Egerton, 20115, Kenya
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi, 00100, Kenya
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45
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Ashton RA, Bennett A, Yukich J, Bhattarai A, Keating J, Eisele TP. Methodological Considerations for Use of Routine Health Information System Data to Evaluate Malaria Program Impact in an Era of Declining Malaria Transmission. Am J Trop Med Hyg 2017; 97:46-57. [PMID: 28990915 PMCID: PMC5619932 DOI: 10.4269/ajtmh.16-0734] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 10/24/2016] [Indexed: 12/01/2022] Open
Abstract
Coverage of malaria control interventions is increasing dramatically across endemic countries. Evaluating the impact of malaria control programs and specific interventions on health indicators is essential to enable countries to select the most effective and appropriate combination of tools to accelerate progress or proceed toward malaria elimination. When key malaria interventions have been proven effective under controlled settings, further evaluations of the impact of the intervention using randomized approaches may not be appropriate or ethical. Alternatives to randomized controlled trials are therefore required for rigorous evaluation under conditions of routine program delivery. Routine health management information system (HMIS) data are a potentially rich source of data for impact evaluation, but have been underused in impact evaluation due to concerns over internal validity, completeness, and potential bias in estimates of program or intervention impact. A range of methodologies were identified that have been used for impact evaluations with malaria outcome indicators generated from HMIS data. Methods used to maximize internal validity of HMIS data are presented, together with recommendations on reducing bias in impact estimates. Interrupted time series and dose-response analyses are proposed as the strongest quasi-experimental impact evaluation designs for analysis of malaria outcome indicators from routine HMIS data. Interrupted time series analysis compares the outcome trend and level before and after the introduction of an intervention, set of interventions or program. The dose-response national platform approach explores associations between intervention coverage or program intensity and the outcome at a subnational (district or health facility catchment) level.
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Affiliation(s)
- Ruth A. Ashton
- Center for Applied Malaria Research and Evaluation, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
| | - Adam Bennett
- Malaria Elimination Initiative, Global Health Group, University of California San Francisco, San Francisco, California
| | - Joshua Yukich
- Center for Applied Malaria Research and Evaluation, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
| | - Achuyt Bhattarai
- President's Malaria Initiative, Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Joseph Keating
- Center for Applied Malaria Research and Evaluation, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
| | - Thomas P. Eisele
- Center for Applied Malaria Research and Evaluation, School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana
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Eckert E, Florey LS, Tongren JE, Salgado SR, Rukundo A, Habimana JP, Hakizimana E, Munguti K, Umulisa N, Mulindahabi M, Karema C. Impact Evaluation of Malaria Control Interventions on Morbidity and All-Cause Child Mortality in Rwanda, 2000-2010. Am J Trop Med Hyg 2017; 97:99-110. [PMID: 28990918 PMCID: PMC5619936 DOI: 10.4269/ajtmh.17-0281] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 06/01/2017] [Indexed: 11/07/2022] Open
Abstract
The impressive decline in child mortality that occurred in Rwanda from 1996-2000 to 2006-2010 coincided with a period of rapid increase of malaria control interventions such as indoor residual spraying (IRS); insecticide-treated net (ITN) distribution and use, and improved malaria case management. The impact of these interventions was examined through ecological correlation analysis, and robust decomposition analysis of contextual factors on all-cause child mortality. Child mortality fell 61% during the evaluation period and prevalence of severe anemia in children 6-23 months declined 71% between 2005 and 2010. These changes in malaria morbidity and mortality occurred concurrently with a substantial increase in vector control activities. ITN use increased among children under five, from 4% to 70%. The IRS program began in 2007 and covered 1.3 million people in the highest burden districts by 2010. At the same time, diagnosis and treatment with an effective antimalarial expanded nationally, and included making services available to children under the age of 5 at the community level. The percentage of children under 5 who sought care for a fever increased from 26% in 2000 to 48% in 2010. Multivariable models of the change in child mortality between 2000 and 2010 using nationally representative data reveal the importance of increasing ITN ownership in explaining the observed mortality declines. Taken as a whole, the evidence supports the conclusion that malaria control interventions contributed to the observed decline in child mortality in Rwanda from 2000 to 2010, even in a context of improving socioeconomic, maternal, and child health conditions.
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Affiliation(s)
- Erin Eckert
- President’s Malaria Initiative (PMI), U.S. Agency for International Development (USAID), Washington, District of Columbia
| | | | - Jon Eric Tongren
- Centers for Disease Control and Prevention (CDC), PMI, Accra, Ghana
| | - S. René Salgado
- President’s Malaria Initiative (PMI), U.S. Agency for International Development (USAID), Washington, District of Columbia
| | - Alphonse Rukundo
- Malaria and Other Parasitic Diseases Division (MOPDD), Rwanda Biomedical Center, Kigali, Rwanda
| | - Jean Pierre Habimana
- Malaria and Other Parasitic Diseases Division (MOPDD), Rwanda Biomedical Center, Kigali, Rwanda
| | - Emmanuel Hakizimana
- Malaria and Other Parasitic Diseases Division (MOPDD), Rwanda Biomedical Center, Kigali, Rwanda
| | - Kaendi Munguti
- President’s Malaria Initiative (PMI), U.S. Agency for International Development (USAID), Kigali, Rwanda
| | - Noella Umulisa
- Maternal and Child Survival Program (MCSP), Jhpiego, Kigali, Rwanda
| | - Monique Mulindahabi
- Malaria and Other Parasitic Diseases Division (MOPDD), Rwanda Biomedical Center, Kigali, Rwanda
| | - Corine Karema
- Swiss Tropical and Public Health Institute and University of Basel, Switzerland
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47
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Hershey CL, Florey LS, Ali D, Bennett A, Luhanga M, Mathanga DP, Salgado SR, Nielsen CF, Troell P, Jenda G, Yé Y, Bhattarai A. Malaria Control Interventions Contributed to Declines in Malaria Parasitemia, Severe Anemia, and All-Cause Mortality in Children Less Than 5 Years of Age in Malawi, 2000-2010. Am J Trop Med Hyg 2017; 97:76-88. [PMID: 28990920 PMCID: PMC5619935 DOI: 10.4269/ajtmh.17-0203] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 05/30/2017] [Indexed: 12/01/2022] Open
Abstract
Malaria control intervention coverage increased nationwide in Malawi during 2000-2010. Trends in intervention coverage were assessed against trends in malaria parasite prevalence, severe anemia (hemoglobin < 8 g/dL), and all-cause mortality in children under 5 years of age (ACCM) using nationally representative household surveys. Associations between insecticide-treated net (ITN) ownership, malaria morbidity, and ACCM were also assessed. Household ITN ownership increased from 27.4% (95% confidence interval [CI] = 25.9-29.0) in 2004 to 56.8% (95% CI = 55.6-58.1) in 2010. Similarly intermittent preventive treatment during pregnancy coverage increased from 28.2% (95% CI = 26.7-29.8) in 2000 to 55.0% (95% CI = 53.4-56.6) in 2010. Malaria parasite prevalence decreased significantly from 60.5% (95% CI = 53.0-68.0) in 2001 to 20.4% (95% CI = 15.7-25.1) in 2009 in children aged 6-35 months. Severe anemia prevalence decreased from 20.4% (95% CI: 17.3-24.0) in 2004 to 13.1% (95% CI = 11.0-15.4) in 2010 in children aged 6-23 months. ACCM decreased 41%, from 188.6 deaths per 1,000 live births (95% CI = 179.1-198.0) during 1996-2000, to 112.1 deaths per 1,000 live births (95% CI = 105.8-118.5) during 2006-2010. When controlling for other covariates in random effects logistic regression models, household ITN ownership was protective against malaria parasitemia in children (odds ratio [OR] = 0.81, 95% CI = 0.72-0.92) and severe anemia (OR = 0.82, 95% CI = 0.72-0.94). After considering the magnitude of changes in malaria intervention coverage and nonmalaria factors, and given the contribution of malaria to all-cause mortality in malaria-endemic countries, the substantial increase in malaria control interventions likely improved child survival in Malawi during 2000-2010.
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Affiliation(s)
- Christine L. Hershey
- President’s Malaria Initiative, Agency for International Development, Washington, District of Columbia
| | - Lia S. Florey
- The DHS Program, ICF International, Rockville, Maryland
| | - Doreen Ali
- National Malaria Control Program, Lilongwe, Malawi
| | - Adam Bennett
- Global Health Group, University of California San Francisco School of Medicine, San Francisco, California
| | | | | | - S. René Salgado
- President’s Malaria Initiative, Agency for International Development, Washington, District of Columbia
| | - Carrie F. Nielsen
- President’s Malaria Initiative, Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Peter Troell
- President’s Malaria Initiative, Centers for Disease Control and Prevention, Lilongwe, Malawi
| | - Gomezgani Jenda
- President’s Malaria Initiative, Agency for International Development, Lilongwe, Malawi
| | - Yazoume Yé
- MEASURE Evaluation, ICF International, Rockville, Maryland
| | - Achuyt Bhattarai
- President’s Malaria Initiative, Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
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48
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Raouf S, Mpimbaza A, Kigozi R, Sserwanga A, Rubahika D, Katamba H, Lindsay SW, Kapella BK, Belay KA, Kamya MR, Staedke SG, Dorsey G. Resurgence of Malaria Following Discontinuation of Indoor Residual Spraying of Insecticide in an Area of Uganda With Previously High-Transmission Intensity. Clin Infect Dis 2017; 65:453-460. [PMID: 28369387 PMCID: PMC5850037 DOI: 10.1093/cid/cix251] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 03/17/2017] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) are the primary tools for malaria prevention in Africa. It is not known whether reductions in malaria can be sustained after IRS is discontinued. Our aim in this study was to assess changes in malaria morbidity in an area of Uganda with historically high transmission where IRS was discontinued after a 4-year period followed by universal LLIN distribution. METHODS Individual-level malaria surveillance data were collected from 1 outpatient department and 1 inpatient setting in Apac District, Uganda, from July 2009 through November 2015. Rounds of IRS were delivered approximately every 6 months from February 2010 through May 2014 followed by universal LLIN distribution in June 2014. Temporal changes in the malaria test positivity rate (TPR) were estimated during and after IRS using interrupted time series analyses, controlling for age, rainfall, and autocorrelation. RESULTS Data include 65 421 outpatient visits and 13 955 pediatric inpatient admissions for which a diagnostic test for malaria was performed. In outpatients aged <5 years, baseline TPR was 60%-80% followed by a rapid and then sustained decrease to 15%-30%. During the 4-18 months following discontinuation of IRS, absolute TPR values increased by an average of 3.29% per month (95% confidence interval, 2.01%-4.57%), returning to baseline levels. Similar trends were seen in outpatients aged ≥5 years and pediatric admissions. CONCLUSIONS Discontinuation of IRS in an area with historically high transmission intensity was associated with a rapid increase in malaria morbidity to pre-IRS levels.
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Affiliation(s)
- Saned Raouf
- Department of Medicine, University of Colorado School of Medicine, Aurora
| | - Arthur Mpimbaza
- Child Health & Development Centre, Makerere University College of Health Sciences
- Uganda Malaria Surveillance Project
| | | | | | - Denis Rubahika
- National Malaria Control Program, Ministry of Health, Kampala, Uganda
| | - Henry Katamba
- National Malaria Control Program, Ministry of Health, Kampala, Uganda
| | - Steve W Lindsay
- School of Biological and Biomedical Sciences, Durham University, United Kingdom
| | - Bryan K Kapella
- US President's Malaria Initiative, Malaria Branch, Division of Parasitic Diseases and Malaria, US Centers for Disease Control and Prevention
| | | | - Moses R Kamya
- School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Sarah G Staedke
- Department of Clinical Research, London School of Hygiene & Tropical Medicine, United Kingdom
| | - Grant Dorsey
- Department of Medicine, University of California San Francisco
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49
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Bayili K, N'do S, Namountougou M, Sanou R, Ouattara A, Dabiré RK, Ouédraogo AG, Malone D, Diabaté A. Evaluation of efficacy of Interceptor ® G2, a long-lasting insecticide net coated with a mixture of chlorfenapyr and alpha-cypermethrin, against pyrethroid resistant Anopheles gambiae s.l. in Burkina Faso. Malar J 2017; 16:190. [PMID: 28482891 PMCID: PMC5422893 DOI: 10.1186/s12936-017-1846-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 05/02/2017] [Indexed: 01/04/2023] Open
Abstract
Background Malaria vectors have acquired widespread resistance throughout sub-Saharan Africa to many of the currently used insecticides. Hence, there is an urgent need to develop alternative strategies including the development of new insecticides for effective management of insecticide resistance. To maintain progress against malaria, it is necessary to identify other residual insecticides for mosquito nets. In the present WHOPES phase II analogue study, the utility of chlorfenapyr, a pyrrole class insecticide mixed with alpha-cypermethrin on a long-lasting mosquito bed net was evaluated against Anopheles gambiae s.l. Methods Bed nets treated with chlorfenapyr and alpha-cypermethrin and mixture of both compounds were tested for their efficacy on mosquitoes. Washed (20 times) and unwashed of each type of treated nets and were tested according to WHOPES guidelines. Efficacy of nets were expressed in terms of blood-feeding inhibition rate, deterrence, induced exophily and mortality rate. The evaluation was conducted in experimental huts of Vallée du Kou seven (VK7) in Burkina Faso (West Africa) following WHOPES phase II guidelines. In addition, a WHOPES phase I evaluation was also performed. Results Mixture treated nets killed significantly (P < 0.05) more mosquitoes than solo alpha-cypermethrin nets, unwashed and washed. Proportionally, this equated to mortalities of 78 and 76% (for mixture nets) compared to only 17 and 10% (for solo alpha-cypermethrin) to An. gambiae, respectively. In contrast mixture net proportions were not significantly (P > 0.05) different from nets treated with chlorfenapyr 200 mg/m2 unwashed (86%). The washed and unwashed nets treated with the mixtures resulted in personal protection against An. gambiae s.l. biting 34 and 44%. In contrast the personal protection observed for washed and unwashed alpha-cypermethrin treated nets generated (14 and 24%), and chlorfenapyr solo treated net was rather low (22%). Conclusion Among all nets trialled, the combination of chlorfenapyr and alpha-cypermethrin on bed nets provided better mortality in phase II after 20 washes. Results suggest that this combination could be a potential insecticide resistance management tool for preventing malaria transmission in areas compromised by the spread of pyrethroid resistance.
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Affiliation(s)
- Koama Bayili
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso.,Universite Polytechnique de Bobo, Bobo-Dioulasso, Burkina Faso
| | - Severin N'do
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso
| | - Moussa Namountougou
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso.,Universite Polytechnique de Bobo, Bobo-Dioulasso, Burkina Faso
| | - Roger Sanou
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso
| | - Abdoulaye Ouattara
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso
| | - Roch K Dabiré
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso
| | - Anicet G Ouédraogo
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso.,Universite Polytechnique de Bobo, Bobo-Dioulasso, Burkina Faso
| | - David Malone
- Innovative Vector Control Consortium/Liverpool, Liverpool, UK
| | - Abdoulaye Diabaté
- Intitut de Recherche en Sciences de la Santé/Centre Muraz, Bobo-Dioulasso, Burkina Faso.
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50
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Krezanoski PJ, Campbell JI, Santorino D, Bangsberg DR. Objective monitoring of Insecticide-treated bednet use to improve malaria prevention: SmartNet development and validation. PLoS One 2017; 12:e0168116. [PMID: 28158233 PMCID: PMC5291529 DOI: 10.1371/journal.pone.0168116] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 11/27/2016] [Indexed: 11/03/2022] Open
Abstract
Malaria is a serious health concern for three billion people worldwide, killing nearly 600,000 people a year. Insecticide-treated bednets (ITNs) are an effective and valuable tool for preventing malaria and hundreds of millions of ITNs have been distributed throughout sub-Saharan Africa. Nevertheless, our current methods for measuring ITN use are inadequate to inform malaria prevention programs. The most common method, self-reported ITN use, is limited by 1) social desirability, 2) recall and 3) sampling bias. An acceptable objective and longitudinal method of assessing adherence to ITN use would improve our ability to better understand the determinants of ITN use and design more effective malaria prevention interventions. We describe the development and initial proof-of-concept validity testing of an ITN adherence monitoring tool called SmartNet. SmartNet uses conductive thread interwoven into an ITN and a microcontroller to detect the state of the ITN. We tested SmartNet among five volunteers using the device over their beds in Boston, USA for two weeks with the goal of evaluating device reliability, accuracy and acceptability to inform future device improvements. The device recorded data for 63.1% (35172/55711) of installed two-minute time intervals, with 97.3% (19990/20539) of the recording errors relating to battery failures. Overall, the device was 71.7% (25204/35172) accurate in determining the state of the ITN (whether it was folded up or unfurled) and performed significantly better at detecting an unfurled ITN than a folded ITN, 77.3% versus 68.4% (p<0.001). Participants noted no significant acceptability concerns and all participants felt SmartNet was easy or very easy to use. SmartNet is a novel approach to objectively measure ITN adherence over time. Our results suggest a variety of device improvements to both extend reliability and improve performance of SmartNet prior to deployment in a malaria-endemic setting.
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Affiliation(s)
- Paul J. Krezanoski
- Department of Medicine, Zuckerberg San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
- Department of Pediatrics, Zuckerberg San Francisco General Hospital, University of California, San Francisco, San Francisco, California, United States of America
- * E-mail:
| | | | - Data Santorino
- Mbarara University of Science and Technology, Mbarara, Uganda
| | - David R. Bangsberg
- Oregon Health Sciences University-Portland State University School of Public Health, Portland, Oregon, United States of America
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