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Damene E, Massebo F. Administration of ivermectin to cattle induced mortality, reduced fecundity and survivorship of Anopheles arabiensis in Ethiopia: an implication for expansion of vector control toolbox. Trop Med Health 2024; 52:11. [PMID: 38229204 PMCID: PMC10790479 DOI: 10.1186/s41182-023-00575-z] [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] [Received: 08/03/2023] [Accepted: 12/27/2023] [Indexed: 01/18/2024] Open
Abstract
BACKGROUND Although many countries have shown interest in eliminating malaria, approaches that complement existing vector control interventions are needed because existing methods have been scaled up but malaria still persists. Therefore, the effect of ivermectin administration to cattle was evaluated for its effect on mortality, survivorship and mortality of laboratory reared Anopheles arabiensis. METHODS Three calves were randomly selected and injected with ivermectin at a therapeutic dose of 0.2 mg/kg, while the other two calves received no treatment and served as controls. Five tents were constructed for the trial. Calves were housed in tents (one per tent) and then 30 starved female An. arabiensis were introduced into each tent. Only fully engorged females were collected from each tent and placed in different mosquito cages to monitor their mortality, survival and fecundity. Data analysis was done using SPSS version 16. RESULTS During the follow-up period (until day 21), ivermectin induced significantly higher mortality when compared to controls. It resulted in an average 24-h mortality rate of 81.6% against An. arabiensis on the first day following treatment. 100% An. arabiensis that fed on ivermectin-treated calves on the first day after treatment died within four days. Egg production rate of An. arabiensis that fed on ivermectin-treated calves was significantly lower compared to controls (F = 768.7, P < 0.001). CONCLUSION In conclusion, ivermectin induced mortality, reduced fecundity and survivorship of laboratory maintained An. arabiensis. Further study is recommended using a wild mosquito population. Moreover, mass ivermectin administration to domestic animals could be recommended to supplement the existing indoor based interventions.
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Affiliation(s)
- Ephrem Damene
- Department of Biology, Arba Minch University, Arba Minch, Ethiopia
| | - Fekadu Massebo
- Department of Biology, Arba Minch University, Arba Minch, Ethiopia.
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Katusi GC, Hermy MRG, Makayula SM, Ignell R, Mnyone LL, Hill SR, Govella NJ. Effect of non-human hosts on the human biting rate of primary and secondary malaria vectors in Tanzania. Malar J 2023; 22:340. [PMID: 37940967 PMCID: PMC10631174 DOI: 10.1186/s12936-023-04778-x] [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: 05/10/2022] [Accepted: 11/01/2023] [Indexed: 11/10/2023] Open
Abstract
BACKGROUND Malaria vectors vary in feeding preference depending on their innate behaviour, host availability and abundance. Host preference and human biting rate in malaria vectors are key factors in establishing zooprophylaxis and zoopotentiation. This study aimed at assessing the impact of non-human hosts in close proximity to humans on the human biting rate of primary and secondary malaria vectors, with varying host preferences. METHODS The effect of the presence of non-human hosts in close proximity to the human host on the mean catches per person per night, as a proxy for mosquito biting rate, was measured using mosquito-electrocuting traps (METs), in Sagamaganga, Kilombero Valley, Tanzania. Two experiments were designed: (1) a human versus a calf, each enclosed in a MET, and (2) a human surrounded by three calves versus a human alone, with each human volunteer enclosed individually in a MET spaced 10 m apart. Each experiment was conducted on alternate days and lasted for 36 nights per experiment. During each experiment, the positions of hosts were exchanged daily (except the human in experiment 2). All anopheline mosquitoes caught were assayed for Plasmodium sporozoites using enzyme-linked immunosorbent assay. RESULTS A total of 20,574 mosquitoes were captured and identified during the study, of which 3608 were anophelines (84.4% primary and 15.6% secondary malaria vectors) and 17,146 were culicines. In experiment 1, the primary malaria vector, Anopheles arabiensis, along with Culex spp. demonstrated a preference for cattle, while the primary vectors, Anopheles funestus, preferred humans. In experiment 2, both primary vectors, An. arabiensis and An. funestus, as well as the secondary vector Anopheles rivolurum, demonstrated behaviours amenable to zooprophylaxis, whereas Culex spp. increased their attraction to humans in the presence of nearby cattle. All anopheline mosquitoes tested negative for sporozoites. CONCLUSIONS The findings of this study provide support for the zooprophylaxis model for malaria vectors present in the Kilombero Valley, and for the zoopotentiation model, as it pertains to the Culex spp. in the region. However, the factors regulating zooprophylaxis and zoopotentiation are complex, with different species-dependent mechanisms regulating these behaviours, that need to be considered when designing integrated vector management programmes.
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Affiliation(s)
- Godfrey C Katusi
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, Off Mlabani Passage, P.O. Box 53, Ifakara, Morogoro, Tanzania
- Department of Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, P.O. Box 3019, Morogoro, Tanzania
| | - Marie R G Hermy
- Disease Vector Group, Unit of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 190, 234 22, Lomma, Sweden
| | - Samwely M Makayula
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, Off Mlabani Passage, P.O. Box 53, Ifakara, Morogoro, Tanzania
| | - Rickard Ignell
- Disease Vector Group, Unit of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 190, 234 22, Lomma, Sweden
| | - Ladslaus L Mnyone
- Institute of Pest Management, Sokoine University of Agriculture, P.O. Box 3110, Morogoro, Tanzania
| | - Sharon R Hill
- Disease Vector Group, Unit of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 190, 234 22, Lomma, Sweden.
| | - Nicodem J Govella
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, Off Mlabani Passage, P.O. Box 53, Ifakara, Morogoro, Tanzania
- School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
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Tarimo FS, Dillip A, Kosia EM, Lwetoijera DW. Community perception of the autodissemination of pyriproxyfen for controlling malaria vectors in south-eastern Tanzania. Malar J 2023; 22:333. [PMID: 37924148 PMCID: PMC10625276 DOI: 10.1186/s12936-023-04773-2] [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: 06/12/2023] [Accepted: 10/26/2023] [Indexed: 11/06/2023] Open
Abstract
BACKGROUND The efficacy of the autodissemination of pyriproxyfen to control malaria vectors has been demonstrated under semi field environment in Tanzania. However, the information on how best communities should be engaged for its routine and large-scale adoption are lacking. This study assessed the community's level of knowledge, perceptions, acceptability of the autodissemination of pyriproxyfen, and the perceived risks on the safety of pyriproxyfen on the environment. METHODS This was a concurrent mixed methods study, comprised of a community-based survey of 400 household representatives and eight focus group discussions (FGDs). The study was conducted in two villages in Mlimba district in south-eastern Tanzania between June and August 2022. For the quantitative data analysis, descriptive statistics were applied using R software, while inductive approach was used for qualitative data analysis, using NVivo software. RESULTS Knowledge on autodissemination of pyriproxyfen approach was found to be relatively low among both the FGD respondents and surveyed community members (36%, n = 144). Nevertheless, when it was explained to them, the envisioned community support for the autodissemination approach was relatively high (97%, n = 388). One of the major perceived benefits of the autodissemination of pyriproxyfen was the reduction of malaria-transmitting mosquitoes and associated malaria transmission. Environmental impact of pyriproxyfen on non-target organisms and health risk to children were among the major concerns. When provided with information on the safety and its utilization particularly through autodissemination approach, 93.5% (n = 374) of the survey respondents said that they would allow the PPF-contaminated pots to be placed around their homes. Similarly, FGD respondents were receptive towards the autodissemination of pyriproxyfen, but emphasized on the need for raising awareness among community members before related field trials. CONCLUSION This study indicates a low knowledge but high support for scaling up of the autodissemination of pyriproxyfen as a complementary tool for malaria control in rural Tanzania. The Findings of this study suggest that community sensitization activities are required to improve the community's acceptability and trust of the approach before respective field trials.
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Affiliation(s)
- Felista S Tarimo
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, United Republic of Tanzania.
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania.
| | - Angel Dillip
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, United Republic of Tanzania
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania
- Apotheker Health Access Initiative, P. O. Box 70022, Dar es Salaam, United Republic of Tanzania
| | - Efraim M Kosia
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania
| | - Dickson W Lwetoijera
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, United Republic of Tanzania.
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania.
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Sagna AB, Zéla L, Ouedraogo COW, Pooda SH, Porciani A, Furnival-Adams J, Lado P, Somé AF, Pennetier C, Chaccour CJ, Dabiré RK, Mouline K. Ivermectin as a novel malaria control tool: Getting ahead of the resistance curse. Acta Trop 2023; 245:106973. [PMID: 37352998 DOI: 10.1016/j.actatropica.2023.106973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/14/2023] [Accepted: 06/16/2023] [Indexed: 06/25/2023]
Abstract
Reduction in malaria clinical cases is strongly dependent on the ability to prevent Anopheles infectious bites. Vector control strategies using long-lasting insecticidal nets and indoor residual spraying with insecticides have contributed to significantly reduce the incidence of malaria in many endemic countries, especially in the Sub-Saharan region. However, global progress in reducing malaria cases has plateaued since 2015 mostly due to the increased insecticide resistance and behavioral changes in Anopheles vectors. Additional control strategies are thus required to further reduce the burden of malaria and contain the spread of resistant and invasive Anopheles vectors. The use of endectocides such as ivermectin as an additional malaria control tool is now receiving increased attention, driven by its different mode of action compared to insecticides used so far and its excellent safety record for humans. In this opinion article, we discuss the advantages and disadvantages of using ivermectin for malaria control with a focus on the risk of selecting ivermectin resistance in malaria vectors. We also highlight the importance of understanding how ivermectin resistance could develop in mosquitoes and what its underlying mechanisms and associated molecular markers are, and propose a research agenda to manage this phenomenon.
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Affiliation(s)
- André B Sagna
- MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France.
| | - Lamidi Zéla
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso
| | - Cheick Oumar W Ouedraogo
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Centre National de Recherche Scientifique et Technologique, Bobo-Dioulasso, Burkina Faso
| | - Sié H Pooda
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso; Université de Dédougou, Dédougou, Burkina Faso
| | | | | | - Paula Lado
- Center for Vector-borne Infectious Diseases, Colorado State University, Fort Collins, CO, USA
| | - Anyirékun F Somé
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Centre National de Recherche Scientifique et Technologique, Bobo-Dioulasso, Burkina Faso
| | - Cédric Pennetier
- MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
| | - Carlos J Chaccour
- ISGlobal, Barcelona Institute for Global Health, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, Madrid, Spain; Universidad de Navarra, Pamplona, Spain
| | - Roch K Dabiré
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Centre National de Recherche Scientifique et Technologique, Bobo-Dioulasso, Burkina Faso
| | - Karine Mouline
- MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
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Kiuru C, Ominde K, Muturi M, Babu L, Wanjiku C, Chaccour C, Maia MF. Effects of larval exposure to sublethal doses of ivermectin on adult fitness and susceptibility to ivermectin in Anopheles gambiae s.s. Parasit Vectors 2023; 16:293. [PMID: 37605264 PMCID: PMC10441747 DOI: 10.1186/s13071-023-05888-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: 03/01/2023] [Accepted: 07/18/2023] [Indexed: 08/23/2023] Open
Abstract
BACKGROUND The effects of ivermectin (endectocide) on mosquito survival make it a potential new malaria vector control tool. The drug can be administered to mosquito disease vectors through blood hosts that include humans and livestock. Its increased use may cause contamination of larval habitats, either directly through livestock excreta or indirectly through leaching or run-off from contaminated soil, albeit in sublethal doses. However, the effects of such exposure on immature stages and the subsequent adults that emerge are poorly understood. This study was undertaken to evaluate the impact of ivermectin exposure on Anopheles gambiae s.s. larvae and its effects on fitness and susceptibility to ivermectin in the emerging adults. METHODS Laboratory-reared An. gambiae s.s. (Kilifi strain) larvae were exposed to five different ivermectin concentrations; 0, 0.00001, 0.0001, 0.001, and 0.01 ppm, and larval survival was monitored to determine the appropriate sub-lethal dose. Concentrations with survival > 50% (0.00001 and 0.0001 ppm) were selected and used as the sub-lethal doses. The fecundity, fertility, and susceptibility to ivermectin of adults emerging after larval exposure to the sub-lethal doses were examined. RESULTS Overall, exposure of An. gambiae s.s. aquatic stages to ivermectin caused a dose-dependent reduction in larval survival irrespective of the stage at which the larvae were exposed. Exposure to ivermectin in the larval stage did not have an effect on either the number of eggs laid or the hatch rate. However, exposure of first/second-instar larvae to 0.0001 ppm and third/fourth-instar larvae to 0.001 ppm of ivermectin reduced the time taken to oviposition. Additionally, exposure to ivermectin in the larval stage did not affect susceptibility of the emerging adults to the drug. CONCLUSIONS This study shows that contamination of larval habitats with ivermectin affects An. gambiae s.s. larval survival and could potentially have an impact on public health. However, there are no carry-over effects on the fecundity, fertility, and susceptibility of the emerging adults to ivermectin. In addition, this study shows that environmental exposure to ivermectin in the larval habitats is unlikely to compromise the efficacy of ivermectin in the emerging adults.
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Affiliation(s)
- Caroline Kiuru
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic - Universitat de Barcelona, Rosello 132, 5ª 2ª, 08036, Barcelona, Spain.
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.
| | - Kelly Ominde
- Department of Biosciences, KEMRI Wellcome Trust Research Programme (KWTRP), Kilifi, 230-80108, Kenya
- Pwani University, Department of Biological Sciences and Pwani University Bioscience Research Centre (PUBReC), Kilifi, Kenya
| | - Martha Muturi
- Department of Biosciences, KEMRI Wellcome Trust Research Programme (KWTRP), Kilifi, 230-80108, Kenya
| | - Lawrence Babu
- Department of Biosciences, KEMRI Wellcome Trust Research Programme (KWTRP), Kilifi, 230-80108, Kenya
| | - Caroline Wanjiku
- Department of Biosciences, KEMRI Wellcome Trust Research Programme (KWTRP), Kilifi, 230-80108, Kenya
| | - Carlos Chaccour
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic - Universitat de Barcelona, Rosello 132, 5ª 2ª, 08036, Barcelona, Spain
- Facultad de Medicina, Universidad de Navarra, 31008, Pamplona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, Madrid, Spain
| | - Marta Ferreira Maia
- Department of Biosciences, KEMRI Wellcome Trust Research Programme (KWTRP), Kilifi, 230-80108, Kenya.
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK.
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Morgan CE, Topazian HM, Brandt K, Mitchell C, Kashamuka MM, Muwonga J, Sompwe E, Juliano JJ, Bobanga T, Tshefu A, Emch M, Parr JB. Association between domesticated animal ownership and Plasmodium falciparum parasite prevalence in the Democratic Republic of the Congo: a national cross-sectional study. THE LANCET. MICROBE 2023; 4:e516-e523. [PMID: 37269868 PMCID: PMC10319634 DOI: 10.1016/s2666-5247(23)00109-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 10/21/2022] [Accepted: 03/17/2023] [Indexed: 06/05/2023]
Abstract
BACKGROUND Domesticated animal ownership is an understudied aspect of the human environment that influences mosquito biting behaviour and malaria transmission, and is a key part of national economies and livelihoods in malaria-endemic regions. In this study, we aimed to understand differences in Plasmodium falciparum prevalence by ownership status of common domesticated animals in DR Congo, where 12% of the world's malaria cases occur and anthropophilic Anopheles gambiae vectors predominate. METHODS In this cross-sectional study, we used survey data from individuals aged 15-59 years in the most recent (2013-14) DR Congo Demographic and Health Survey and previously performed Plasmodium quantitative real-time PCR (qPCR) to estimate P falciparum prevalence differences by household ownership of cattle; chickens; donkeys, horses, or mules; ducks; goats; sheep; and pigs. We used directed acyclic graphs to consider confounding by age, gender, wealth, modern housing, treated bednet use, agricultural land ownership, province, and rural location. FINDINGS Of 17 701 participants who had qPCR results and covariate data, 8917 (50·4%) of whom owned a domesticated animal, we observed large differences in malaria prevalence across types of animals owned in both crude and adjusted models. Household chicken ownership was associated with 3·9 (95% CI 0·6 to 7·1) more P falciparum infections per 100 people, whereas cattle ownership was associated with 9·6 (-15·8 to -3·5) fewer P falciparum infections per 100 people, even after accounting for bednet use, wealth, and housing structure. INTERPRETATION Our finding of a protective association conferred by cattle ownership suggests that zooprophylaxis interventions might have a role in DR Congo, possibly by drawing An gambiae feeding away from humans. Studies of animal husbandry practices and associated mosquito behaviours could reveal opportunities for new malaria interventions. FUNDING The National Institutes of Health and the Bill & Melinda Gates Foundation. TRANSLATIONS For the French and Lingala translations of the abstract see Supplementary Materials section.
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Affiliation(s)
- Camille E Morgan
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Hillary M Topazian
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Katerina Brandt
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Cedar Mitchell
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Jérémie Muwonga
- Programme National de La Lutte Contre Le SIDA, Kinshasa, DR Congo
| | - Eric Sompwe
- Programme National de La Lutte Contre Le Paludisme, Kinshasa, DR Congo; Faculty of Medicine, School of Public Health, University of Lubumbashi, Kinshasa, DR Congo
| | - Jonathan J Juliano
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Division of Infectious Diseases, Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Thierry Bobanga
- Department of Tropical Medicine, Faculty of Medicine, University of Kinshasa, Kinshasa, DR Congo
| | | | - Michael Emch
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jonathan B Parr
- Division of Infectious Diseases, Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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Wang C, Thakuri B, Roy AK, Mondal N, Qi Y, Chakraborty A. Changes in the associations between malaria incidence and climatic factors across malaria endemic countries in Africa and Asia-Pacific region. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 331:117264. [PMID: 36634422 DOI: 10.1016/j.jenvman.2023.117264] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/30/2022] [Accepted: 01/08/2023] [Indexed: 06/17/2023]
Abstract
Empirical evidence supporting the associations between malaria incidence and climatic factors has remained controversial, buffering the progress in the Global Malaria Program that aims to eliminate 90% of the world malaria burden by 2030. This study has aimed to evaluate the nature and extent at which these relations are maintained across all the malaria endemic countries of Africa and Asia-Pacific region. We have utilized the last two decades of malaria incidence, annual minimum temperature, and annual precipitation time series data (2000-2020) for the two most malaria-impacted regions. These data were fitted in the generalized linear model and the mixed effects model. The results showed that there exists a large heterogeneity in malaria incidence across the countries, and between the regions. Last two decadal tendencies showed significant reductions in the disease burden in almost all the countries in the Asia Pacific, with several exceptions or relatively slowed reductions in the Africa. We found significant changes in the positive linear associations between malaria incidence, annual minimum temperature, and annual precipitation across African countries. Many Asia-Pacific countries namely Bangladesh, Bhutan, Indonesia, South Korea, Nepal, Thailand, Vietnam showed negative effects in the associations with the annual precipitation. This study indicates that increasing temperature within the range of 12-30 °C can generate positive effects on malaria incidence, but the nature and extent of precipitation effects vary across countries and at a large regional scale.
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Affiliation(s)
- Ce Wang
- School of Energy and Environment, Southeast University, Nanjing, 210096, PR China; State Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, 210096, PR China.
| | - Bikash Thakuri
- Department of Mathematics, School of Physical Sciences, Sikkim University, Gangtok, 737102, Sikkim, India.
| | - Amit Kumar Roy
- Department of Mathematics, School of Physical Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Nitish Mondal
- Department of Anthropology, School of Human Sciences, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Yi Qi
- School of Architecture and Urban Planning, Nanjing University, Nanjing, 210093, PR China
| | - Amit Chakraborty
- Department of Mathematics, School of Physical Sciences, Sikkim University, Gangtok, 737102, Sikkim, India.
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Pooda SH, Moiroux N, Porciani A, Courjaud AL, Roberge C, Gaudriault G, Sidibé I, Belem AMG, Rayaissé JB, Dabiré RK, Mouline K. Proof-of-concept study for a long-acting formulation of ivermectin injected in cattle as a complementary malaria vector control tool. Parasit Vectors 2023; 16:66. [PMID: 36788608 PMCID: PMC9926456 DOI: 10.1186/s13071-022-05621-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 12/15/2022] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND Domesticated animals play a role in maintaining residual transmission of Plasmodium parasites of humans, by offering alternative blood meal sources for malaria vectors to survive on. However, the blood of animals treated with veterinary formulations of the anti-helminthic drug ivermectin can have an insecticidal effect on adult malaria vector mosquitoes. This study therefore assessed the effects of treating cattle with long-acting injectable formulations of ivermectin on the survival of an important malaria vector species, to determine whether it has potential as a complementary vector control measure. METHODS Eight head of a local breed of cattle were randomly assigned to either one of two treatment arms (2 × 2 cattle injected with one of two long-acting formulations of ivermectin with the BEPO® technology at the therapeutic dose of 1.2 mg/kg), or one of two control arms (2 × 2 cattle injected with the vehicles of the formulations). The lethality of the formulations was evaluated on 3-5-day-old Anopheles coluzzii mosquitoes through direct skin-feeding assays, from 1 to 210 days after treatment. The efficacy of each formulation was evaluated and compared using Cox proportional hazards survival models, Kaplan-Meier survival estimates, and log-logistic regression on cumulative mortality. RESULTS Both formulations released mosquitocidal concentrations of ivermectin until 210 days post-treatment (hazard ratio > 1). The treatments significantly reduced mosquito survival, with average median survival time of 4-5 days post-feeding. The lethal concentrations to kill 50% of the Anopheles (LC50) before they became infectious (10 days after an infectious blood meal) were maintained for 210 days post-injection for both formulations. CONCLUSIONS This long-lasting formulation of ivermectin injected in cattle could complement insecticide-treated nets by suppressing field populations of zoophagic mosquitoes that are responsible, at least in part, for residual malaria transmission. The impact of this approach will of course depend on the field epidemiological context. Complementary studies will be necessary to characterize ivermectin withdrawal times and potential environmental toxicity.
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Affiliation(s)
- Sié Hermann Pooda
- Université de Dédougou, Dedougou, Burkina Faso
- Centre International de Recherche et Développement pour l’Élevage en zones Sub-humides, Bobo-Dioulasso, Burkina Faso
- Insectarium de Bobo Dioulasso – Campagne d’éradication de la mouche Tsé Tsé et des Trypanosomoses, Bobo-Dioulasso, Burkina Faso
- Université Nazi Boni, Bobo-Dioulasso, Burkina Faso
| | - Nicolas Moiroux
- MIVEGEC, Université de Montpellier-CNRS-IRD, Montpellier, France
| | | | | | | | | | - Issa Sidibé
- Insectarium de Bobo Dioulasso – Campagne d’éradication de la mouche Tsé Tsé et des Trypanosomoses, Bobo-Dioulasso, Burkina Faso
| | | | - Jean-Baptiste Rayaissé
- Centre International de Recherche et Développement pour l’Élevage en zones Sub-humides, Bobo-Dioulasso, Burkina Faso
| | - Roch K. Dabiré
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | - Karine Mouline
- MIVEGEC, Université de Montpellier-CNRS-IRD, Montpellier, France
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Kositz C, Bradley J, Hutchins H, Last A, D'Alessandro U, Marks M. Broadening the range of use cases for ivermectin - a review of the evidence. Trans R Soc Trop Med Hyg 2022; 116:201-212. [PMID: 34323283 PMCID: PMC8890779 DOI: 10.1093/trstmh/trab114] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/30/2021] [Accepted: 07/13/2021] [Indexed: 11/12/2022] Open
Abstract
Ivermectin is a broad-spectrum antiparasitic agent that interferes with glutamate-gated chloride channels found in invertebrates but not in vertebrate species. Mass drug administration (MDA) with ivermectin-based regimes has been a mainstay of elimination efforts targeting onchocerciasis and lymphatic filariasis for more than 3 decades. More recently, interest in the use of ivermectin to control other neglected tropical diseases (NTDs) such as soil-transmitted helminths and scabies has grown. Interest has been further stimulated by the fact that ivermectin displays endectocidal efficacy against various Anopheles species capable of transmitting malaria. Therefore there is growing interest in using ivermectin MDA as a tool that might aid in the control of both malaria and several NTDs. In this review we outline the evidence base to date on these emerging indications for ivermectin MDA with reference to clinical and public health data and discuss the rationale for evaluating the range of impacts of a malaria ivermectin MDA on other NTDs.
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Affiliation(s)
- Christian Kositz
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK
| | - John Bradley
- MRC International Statistics and Epidemiology Group, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK
| | - Harry Hutchins
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK
| | - Anna Last
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK
- Hospital for Tropical Diseases, Mortimer Market Capper Street, WC1E 6JB, London, UK
| | - Umberto D'Alessandro
- Disease Control and Elimination, Medical Research Council Unit Gambia at London School of Hygiene and Tropical Medicine, Atlantic Boulevard, Fajara, The Gambia
| | - Michael Marks
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK
- Hospital for Tropical Diseases, Mortimer Market Capper Street, WC1E 6JB, London, UK
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10
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Picot S, Beugnet F, Leboucher G, Bienvenu AL. Drug resistant parasites and fungi from a one-health perspective: A global concern that needs transdisciplinary stewardship programs. One Health 2021; 14:100368. [PMID: 34957316 PMCID: PMC8692089 DOI: 10.1016/j.onehlt.2021.100368] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 12/12/2022] Open
Abstract
Antimicrobials including antibiotics, antiparasitic, and antifungals, are subjected to resistance. In this context, Public Health Organizations called for a One Health approach because antimicrobials used to treat different infectious diseases in animals and plants may be the same than those used in humans. Whereas mechanisms of resistance transmission from animals or environment to humans should be considered differently if related to prokaryotic or eukaryotic pathogens, their impact can be considered as a whole. In that respect, we discussed the use of anti-parasitic in animals including anticoccidials, anthelmintics, and insecticides-acaricides, and the use of azoles in the environment that may both favor the development of drug resistance in humans. In light of the current situation, there is an urgent need for a transdisciplinary approach through anti-parasitic and antifungal stewardship programs in humans, animals, and environment, especially in the era of COVID-19 pandemic that will probably aggravate antimicrobial resistance.
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Affiliation(s)
- Stephane Picot
- Univ Lyon, Malaria Research Unit, SMITh, ICBMS UMR 5246, Lyon, France.,Institut de Parasitologie et Mycologie Medicale, Hospices Civils de Lyon, Lyon, France
| | | | - Gilles Leboucher
- Service Pharmacie, Groupement Hospitalier Nord, Hospices Civils de Lyon, Lyon, France
| | - Anne-Lise Bienvenu
- Univ Lyon, Malaria Research Unit, SMITh, ICBMS UMR 5246, Lyon, France.,Service Pharmacie, Groupement Hospitalier Nord, Hospices Civils de Lyon, Lyon, France
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11
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Vythilingam I, Chua TH, Liew JWK, Manin BO, Ferguson HM. The vectors of Plasmodium knowlesi and other simian malarias Southeast Asia: challenges in malaria elimination. ADVANCES IN PARASITOLOGY 2021; 113:131-189. [PMID: 34620382 DOI: 10.1016/bs.apar.2021.08.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Plasmodium knowlesi, a simian malaria parasite of great public health concern has been reported from most countries in Southeast Asia and exported to various countries around the world. Currently P. knowlesi is the predominant species infecting humans in Malaysia. Besides this species, other simian malaria parasites such as P. cynomolgi and P. inui are also infecting humans in the region. The vectors of P. knowlesi and other Asian simian malarias belong to the Leucosphyrus Group of Anopheles mosquitoes which are generally forest dwelling species. Continual deforestation has resulted in these species moving into forest fringes, farms, plantations and human settlements along with their macaque hosts. Limited studies have shown that mosquito vectors are attracted to both humans and macaque hosts, preferring to bite outdoors and in the early part of the night. We here review the current status of simian malaria vectors and their parasites, knowledge of vector competence from experimental infections and discuss possible vector control measures. The challenges encountered in simian malaria elimination are also discussed. We highlight key knowledge gaps on vector distribution and ecology that may impede effective control strategies.
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Affiliation(s)
- Indra Vythilingam
- Department of Parasitology, University of Malaya, Kuala Lumpur, Malaysia.
| | - Tock Hing Chua
- Department of Pathobiology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Sabah Malaysia, Kota Kinabalu, Sabah, Malaysia.
| | - Jonathan Wee Kent Liew
- Department of Parasitology, University of Malaya, Kuala Lumpur, Malaysia; Environmental Health Institute, National Environment Agency, Singapore, Singapore
| | - Benny O Manin
- Department of Pathobiology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Sabah Malaysia, Kota Kinabalu, Sabah, Malaysia
| | - Heather M Ferguson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland, United Kingdom
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12
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Singh L, Singh K. Ivermectin: A Promising Therapeutic for Fighting Malaria. Current Status and Perspective. J Med Chem 2021; 64:9711-9731. [PMID: 34242031 DOI: 10.1021/acs.jmedchem.1c00498] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Finding new chemotherapeutic interventions to treat malaria through repurposing of time-tested drugs and rigorous design of new drugs using tools of rational drug design remains one of the most sought strategies at the disposal of medicinal chemists. Ivermectin, a semisynthetic derivative of avermectin B1, is among the efficacious drugs used in mass drug administration drives employed against onchocerciasis, lymphatic filariasis, and several other parasitic diseases in humans. In this review, we present the prowess of ivermectin, a potent endectocide, in the control of malaria through vector control to reduce parasite transmission combined with efficacious chemoprevention to reduce malaria-related fatalities.
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Affiliation(s)
- Lovepreet Singh
- Department of Chemistry, UGC Centre for Advanced Studies-II, Guru Nanak Dev University, Amritsar-143 005, India
| | - Kamaljit Singh
- Department of Chemistry, UGC Centre for Advanced Studies-II, Guru Nanak Dev University, Amritsar-143 005, India
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13
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Jones RT, Ant TH, Cameron MM, Logan JG. Novel control strategies for mosquito-borne diseases. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190802. [PMID: 33357056 PMCID: PMC7776938 DOI: 10.1098/rstb.2019.0802] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2020] [Indexed: 12/23/2022] Open
Abstract
Mosquito-borne diseases are an increasing global health challenge, threatening over 40% of the world's population. Despite major advances in malaria control since 2000, recent progress has stalled. Additionally, the risk of Aedes-borne arboviruses is rapidly growing, with the unprecedented spread of dengue and chikungunya viruses, outbreaks of yellow fever and the 2015 epidemic of Zika virus in Latin America. To counteract this growing problem, diverse and innovative mosquito control technologies are currently under development. Conceptually, these span an impressive spectrum of approaches, from invasive transgene cassettes with the potential to crash mosquito populations or reduce the vectorial capacity of a population, to low-cost alterations in housing design that restrict mosquito entry. This themed issue will present articles providing insight into the breadth of mosquito control research, while demonstrating the requirement for an interdisciplinary approach. The issue will highlight mosquito control technologies at varying stages of development and includes both opinion pieces and research articles with laboratory and field-based data on control strategy development. This article is part of the theme issue 'Novel control strategies for mosquito-borne diseases'.
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Affiliation(s)
- Robert T. Jones
- Department of Disease Control, London School of Hygiene & Tropical Medicine, Keppel Street, Bloomsbury, London WC1E 7HT, UK
| | - Thomas H. Ant
- Centre for Virus Research, Bearsden Road, Bearsden, Glasgow G61 1QH, UK
| | - Mary M. Cameron
- Department of Disease Control, London School of Hygiene & Tropical Medicine, Keppel Street, Bloomsbury, London WC1E 7HT, UK
| | - James G. Logan
- Department of Disease Control, London School of Hygiene & Tropical Medicine, Keppel Street, Bloomsbury, London WC1E 7HT, UK
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