1
|
Fodjo BK, Tchicaya E, Yao LA, Edi C, Ouattara AF, Kouassi LB, Yokoly FN, Benjamin KG. Efficacy of Pirikool® 300 CS used for indoor residual spraying on three different substrates in semi-field experimental conditions. Malar J 2024; 23:148. [PMID: 38750468 PMCID: PMC11097411 DOI: 10.1186/s12936-024-04912-3] [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: 07/05/2023] [Accepted: 03/19/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND Vector control using insecticides is a key prevention strategy against malaria. Unfortunately, insecticide resistance in mosquitoes threatens all progress in malaria control. In the perspective of managing this resistance, new insecticide formulations are being tested to improve the effectiveness of vector control tools. METHODS The efficacy and residual activity of Pirikool® 300 CS was evaluated in comparison with Actellic® 300 CS in experimental huts at the Tiassalé experimental station on three substrates including cement, wood and mud. The mortality, blood-feeding inhibition, exiting behaviour and deterrency of free-flying wild mosquitoes was evaluated. Cone bioassay tests with susceptible and resistant mosquito strains were conducted in the huts to determine residual efficacy. RESULTS A total of 20,505 mosquitoes of which 10,979 (53%) wild female Anopheles gambiae were collected for 112 nights. Residual efficacy obtained from monthly cone bioassay was higher than 80% with the susceptible, laboratory-maintained An. gambiae Kisumu strain, from the first to the tenth study period on all three types of treated substrate for both Actellic® 300CS and Pirikool® 300CS. This residual efficacy on the wild Tiassalé strain was over 80% until the 4th month of study on Pirikool® 300CS S treated substrates. Overall 24-h mortalities of wild free-flying An. gambiae sensu lato which entered in the experimental huts over the 8-months trial on Pirikool® 300CS treatment was 50.5%, 75.9% and 52.7%, respectively, on cement wall, wood wall and mud wall. The positive reference product Actellic® 300CS treatment induced mortalities of 42.0%, 51.8% and 41.8% on cement wall, wood wall and mud wall. CONCLUSION Pirikool® 300CS has performed really well against resistant strains of An. gambiae using indoor residual spraying method in experimental huts. It could be an alternative product for indoor residual spraying in response to the vectors' resistance to insecticides.
Collapse
Affiliation(s)
- Behi Kouadio Fodjo
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire.
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire.
| | - Emile Tchicaya
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
- Université Peleforo Gon Coulibaly (UPGC), Korhogo, Côte d'Ivoire
| | - Laurence Aya Yao
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
| | - Constant Edi
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
| | - Alassane Foungoye Ouattara
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Loukou Bernard Kouassi
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
| | - Firmain N'dri Yokoly
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Koudou Guibéhi Benjamin
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| |
Collapse
|
2
|
Ndiaye F, Diop A, Chabi J, Sturm-Ramirez K, Senghor M, Diouf EH, Samb B, Diedhiou SM, Thiaw O, Zohdy S, Dotson E, Sene D, Diouf MB, Koscelnik V, Gerberg L, Bangoura A, Clark T, Faye O, Dia I, Konate L, Niang EHA. Distribution and dynamics of Anopheles gambiae s.l. larval habitats in three Senegalese cities with high urban malaria incidence. PLoS One 2024; 19:e0303473. [PMID: 38743768 PMCID: PMC11093314 DOI: 10.1371/journal.pone.0303473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 04/15/2024] [Indexed: 05/16/2024] Open
Abstract
Urban malaria has become a challenge for most African countries due to urbanization, with increasing population sizes, overcrowding, and movement into cities from rural localities. The rapid expansion of cities with inappropriate water drainage systems, abundance of water storage habitats, coupled with recurrent flooding represents a concern for water-associated vector borne diseases, including malaria. This situation could threaten progress made towards malaria elimination in sub-Saharan countries, including Senegal, where urban malaria has presented as a threat to national elimination gains. To assess drivers of urban malaria in Senegal, a 5-month study was carried out from August to December 2019 in three major urban areas and hotspots for malaria incidence (Diourbel, Touba, and Kaolack) including the rainy season (August-October) and partly dry season (November-December). The aim was to characterize malaria vector larval habitats, vector dynamics across both seasons, and to identify the primary eco- environmental entomological factors contributing to observed urban malaria transmission. A total of 145 Anopheles larval habitats were found, mapped, and monitored monthly. This included 32 in Diourbel, 83 in Touba, and 30 in Kaolack. The number of larval habitats fluctuated seasonally, with a decrease during the dry season. In Diourbel, 22 of the 32 monitored larval habitats (68.75%) were dried out by December and considered temporary, while the remaining 10 (31.25%) were classified as permanent. In the city of Touba 28 (33.73%) were temporary habitats, and of those 57%, 71% and 100% dried up respectively by October, November, and December. However, 55 (66.27%) habitats were permanent water storage basins which persisted throughout the study. In Kaolack, 12 (40%) permanent and 18 (60%) temporary Anopheles larval habitats were found and monitored during the study. Three malaria vectors (An. arabiensis, An. pharoensis and An. funestus s.l.) were found across the surveyed larval habitats, and An. arabiensis was found in all three cities and was the only species found in the city of Diourbel, while An. arabiensis, An. pharoensis, and An. funestus s.l. were detected in the cities of Touba and Kaolack. The spatiotemporal observations of immature malaria vectors in Senegal provide evidence of permanent productive malaria vector larval habitats year-round in three major urban centers in Senegal, which may be driving high urban malaria incidence. This study aimed to assess the presence and type of anopheline larvae habitats in urban areas. The preliminary data will better inform subsequent detailed additional studies and seasonally appropriate, cost-effective, and sustainable larval source management (LSM) strategies by the National Malaria Control Programme (NMCP).
Collapse
Affiliation(s)
- Fatou Ndiaye
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - Abdoulaye Diop
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
- U.S. President’s Malaria Initiative VectorLink Project, Dakar, Senegal
| | - Joseph Chabi
- U.S. PMI VectorLink Project, Abt Associates, Rockville, MD, United States of America
| | | | - Massila Senghor
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - El Hadji Diouf
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - Badara Samb
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - Seynabou Mocote Diedhiou
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - Omar Thiaw
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - Sarah Zohdy
- U.S President’s Malaria Initiative, Centers for Disease Control and Prevention (CDC), Atlanta, GA, United States of America
| | - Ellen Dotson
- U.S President’s Malaria Initiative, Centers for Disease Control and Prevention (CDC), Atlanta, GA, United States of America
| | - Doudou Sene
- National Malaria Control Programme, Dakar, Senegal
| | | | | | - Lilia Gerberg
- U.S. President’s Malaria Initiative, United States Agency for International Development (USAID), Washington, DC, United States of America
| | - Abdoulaye Bangoura
- U.S. PMI VectorLink Project, Abt Associates, Rockville, MD, United States of America
| | - Tiffany Clark
- U.S. PMI VectorLink Project, Abt Associates, Rockville, MD, United States of America
| | - Ousmane Faye
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - Ibrahima Dia
- Institut Pasteur de Dakar, Unité d’Entomologie Médicale, Dakar, Senegal
| | - Lassana Konate
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| | - El Hadji Amadou Niang
- Laboratoire d’Ecologie Vectorielle et Parasitaire, Université Cheikh Anta Diop de Dakar, Dakar, Sénégal
| |
Collapse
|
3
|
Abossie A, Demissew A, Getachew H, Tsegaye A, Degefa T, Habtamu K, Zhong D, Wang X, Lee MC, Zhou G, King CL, Kazura JW, Yan G, Yewhalaw D. Higher outdoor mosquito density and Plasmodium infection rates in and around malaria index case households in low transmission settings of Ethiopia: Implications for vector control. Parasit Vectors 2024; 17:53. [PMID: 38321572 PMCID: PMC10848356 DOI: 10.1186/s13071-023-06088-2] [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] [Accepted: 12/07/2023] [Indexed: 02/08/2024] Open
Abstract
BACKGROUND Understanding the clustering of infections for persistent malaria transmission is critical to determining how and where to target specific interventions. This study aimed to determine the density, blood meal sources and malaria transmission risk of anopheline vectors by targeting malaria index cases, their neighboring households and control villages in Arjo-Didessa, southwestern Ethiopia. METHODS An entomological study was conducted concurrently with a reactive case detection (RCD) study from November 2019 to October 2021 in Arjo Didessa and the surrounding vicinity, southwestern Ethiopia. Anopheline mosquitoes were collected indoors and outdoors in index case households and their surrounding households (neighboring households), as well as in control households, using pyrethrum spray cache (PSC) and U.S. Centers for Disease Control and Prevention (CDC) light traps. Adult mosquitoes were morphologically identified, and speciation in the Anopheles gambiae complex was done by PCR. Mosquito Plasmodium infections and host blood meal sources were detected by circumsporozoite protein enzyme-linked immunosorbent assay (CSP-ELISA) and cytochrome b-based blood meal PCR, respectively. RESULTS Among the 770 anopheline mosquitoes collected, An. gambiae sensu lato (A. gambiae s.l.) was the predominant species, accounting for 87.1% (n = 671/770) of the catch, followed by the Anopheles coustani complex and Anopheles pharoensis, which accounted for 12.6% (n = 97/770) and 0.26% (n = 2/770) of the catch, respectively. From the sub-samples of An. gambiae s.l.analyzed with PCR, An. arabiensis and Anopheles amharicus were identified. The overall mean density of mosquitoes was 1.26 mosquitoes per trap per night using the CDC light traps. Outdoor mosquito density was significantly higher than indoor mosquito density in the index and neighboring households (P = 0.0001). The human blood index (HBI) and bovine blood index (BBI) of An. arabiensis were 20.8% (n = 34/168) and 24.0% (n = 41/168), respectively. The overall Plasmodium sporozoite infection rate of anophelines (An. arabiensis and An. coustani complex) was 4.4% (n = 34/770). Sporozoites were detected indoors and outdoors in captured anopheline mosquitoes. Of these CSP-positive species for Pv-210, Pv-247 and Pf, 41.1% (n = 14/34) were captured outdoors. A significantly higher proportion of sporozoite-infected mosquitoes were caught in index case households (5.6%, n = 8/141) compared to control households (1.1%, n = 2/181) (P = 0.02), and in neighboring households (5.3%, n = 24/448) compared to control households (P = 0.01). CONCLUSIONS The findings of this study indicated that malaria index cases and their neighboring households had higher outdoor mosquito densities and Plasmodium infection rates. The study also highlighted a relatively higher outdoor mosquito density, which could increase the potential risk of outdoor malaria transmission and may play a role in residual malaria transmission. Thus, it is important to strengthen the implementation of vector control interventions, such as targeted indoor residual spraying, long-lasting insecticidal nets and other supplementary vector control measures such as larval source management and community engagement approaches. Furthermore, in low transmission settings, such as the Arjo Didessa Sugarcane Plantation, providing health education to local communities, enhanced environmental management and entomological surveillance, along with case detection and management by targeting of malaria index cases and their immediate neighboring households, could be important measures to control residual malaria transmission and achieve the targeted elimination goals.
Collapse
Affiliation(s)
- Ashenafi Abossie
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia.
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia.
| | - Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Hallelujah Getachew
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Technology, Arba Minch College of Health Sciences, Arba Minch, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Arega Tsegaye
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Biology, College of Natural Science, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Teshome Degefa
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Kassahun Habtamu
- Menelik II College of Health Sciences, Addis Ababa, Ethiopia
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Daibin Zhong
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Xiaoming Wang
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Guofa Zhou
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Christopher L King
- Center for Global Health & Diseases, School of Medicine, Case Western Reserve University, Cleveland, 44106 OH, USA
| | - James W Kazura
- Center for Global Health & Diseases, School of Medicine, Case Western Reserve University, Cleveland, 44106 OH, USA
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| |
Collapse
|
4
|
Jiang A, Lee M, Selvaraj P, Degefa T, Getachew H, Merga H, Yewhalaw D, Yan G, Hsu K. Investigating the Impact of Irrigation on Malaria Vector Larval Habitats and Transmission Using a Hydrology-Based Model. GEOHEALTH 2023; 7:e2023GH000868. [PMID: 38089068 PMCID: PMC10711417 DOI: 10.1029/2023gh000868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 10/13/2023] [Accepted: 11/20/2023] [Indexed: 02/01/2024]
Abstract
A combination of accelerated population growth and severe droughts has created pressure on food security and driven the development of irrigation schemes across sub-Saharan Africa. Irrigation has been associated with increased malaria risk, but risk prediction remains difficult due to the heterogeneity of irrigation and the environment. While investigating transmission dynamics is helpful, malaria models cannot be applied directly in irrigated regions as they typically rely only on rainfall as a source of water to quantify larval habitats. By coupling a hydrologic model with an agent-based malaria model for a sugarcane plantation site in Arjo, Ethiopia, we demonstrated how incorporating hydrologic processes to estimate larval habitats can affect malaria transmission. Using the coupled model, we then examined the impact of an existing irrigation scheme on malaria transmission dynamics. The inclusion of hydrologic processes increased the variability of larval habitat area by around two-fold and resulted in reduction in malaria transmission by 60%. In addition, irrigation increased all habitat types in the dry season by up to 7.4 times. It converted temporary and semi-permanent habitats to permanent habitats during the rainy season, which grew by about 24%. Consequently, malaria transmission was sustained all-year round and intensified during the main transmission season, with the peak shifted forward by around 1 month. Lastly, we evaluated the spatiotemporal distribution of adult vectors under the effect of irrigation by resolving habitat heterogeneity. These findings could help larval source management by identifying transmission hotspots and prioritizing resources for malaria elimination planning.
Collapse
Affiliation(s)
- Ai‐Ling Jiang
- Department of Civil and Environmental EngineeringCenter for Hydrometeorology and Remote SensingUniversity of California IrvineIrvineCAUSA
| | - Ming‐Chieh Lee
- Department of Population Health and Disease PreventionSchool of Public HealthSusan and Henry Samueli College of Health SciencesUniversity of California IrvineIrvineCAUSA
| | - Prashanth Selvaraj
- Institute for Disease ModelingBill and Melinda Gates FoundationSeattleWAUSA
| | - Teshome Degefa
- School of Medical Laboratory SciencesInstitute of HealthJimma UniversityJimmaEthiopia
- Tropical and Infectious Diseases Research Center (TIDRC)Jimma UniversityJimmaEthiopia
| | - Hallelujah Getachew
- School of Medical Laboratory SciencesInstitute of HealthJimma UniversityJimmaEthiopia
- Tropical and Infectious Diseases Research Center (TIDRC)Jimma UniversityJimmaEthiopia
- Department of Medical Laboratory TechnologyArbaminch College of Health SciencesArba MinchEthiopia
| | - Hailu Merga
- Department of EpidemiologyInstitute of HealthJimma UniversityJimmaEthiopia
| | - Delenasaw Yewhalaw
- School of Medical Laboratory SciencesInstitute of HealthJimma UniversityJimmaEthiopia
- Tropical and Infectious Diseases Research Center (TIDRC)Jimma UniversityJimmaEthiopia
| | - Guiyun Yan
- Department of Population Health and Disease PreventionSchool of Public HealthSusan and Henry Samueli College of Health SciencesUniversity of California IrvineIrvineCAUSA
| | - Kuolin Hsu
- Department of Civil and Environmental EngineeringCenter for Hydrometeorology and Remote SensingUniversity of California IrvineIrvineCAUSA
| |
Collapse
|
5
|
Tsegaye A, Demissew A, Hawaria D, Abossie A, Getachew H, Habtamu K, Degefa T, Wang X, Lee MC, Zhou G, Yewhalaw D, Yan G. Anopheles larval habitats seasonality and environmental factors affecting larval abundance and distribution in Arjo-Didessa sugar cane plantation, Ethiopia. Malar J 2023; 22:350. [PMID: 37968712 PMCID: PMC10652594 DOI: 10.1186/s12936-023-04782-1] [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: 07/09/2023] [Accepted: 11/02/2023] [Indexed: 11/17/2023] Open
Abstract
BACKGROUND Water resource development projects are essential for increasing agricultural productivity and ensuring food security. However, these activities require the modification of pre-existing environmental settings, which may alter mosquito larval habitat availability and seasonality. The intensive utilization of current adult vector control tools results in insecticide resistance among the main vectors. When coupled with behavioural resistances, a shift in malaria vector feeding and resting behaviours could compromise the effectiveness of the current adult vector control strategies. Thus, it is important to look for new or alternative vector control interventions for immatures to complement adult control by focusing on different larval habitats and their seasonal availability. Thus, this study investigated larval habitat seasonality and seasonal larval abundance and distribution in irrigated sugar cane plantation settings in Ethiopia. METHODS Anopheles mosquito larval habitats were surveyed and visited twice a month for a period of 14 months. Anopheline larvae and pupae were collected, reared, and fed finely ground fish food. Adults were provided with sucrose solution and kept under standard conditions. Female Anopheles mosquitoes were identified morphologically and using a species-specific PCR assay. Environmental parameters, which include habitats' physico-chemical characteristics, were assessed. Larval habitat diversity and larval abundance and distribution were determined across different seasons. RESULTS The study revealed that Anopheles gambiae sensu lato (s.l.) was the most predominant 4197(57%) vector species, followed by Anopheles coustani complex 2388 (32.8%). Molecular analysis of sub-samples of An. gambiae s.l. resulted in Anopheles arabiensis (77.9%) and Anopheles amharicus (21.5%), and the remaining 1.1% (n = 7) sub-samples were not amplified. Physico-chemical parameters such as temperature (t = 2.22, p = 0.028), conductivity (t = 3.21, p = 0.002), dissolved oxygen (t = 7.96, p = 0.001), nitrate ion (t = 2.51, p = 0.013), and ammonium ion (t = 2.26, p = 0.025) showed a significant and direct association with mosquito larval abundance. Furthermore, mosquito larval abundance was correlated with distance to the nearest houses (r = - 0.42, p = 0.001), exposure to sunlight (r = 0.34, p = 0.001), during long and short rainy season animal hoof prints, truck tires/road puddles and rain pools were negatively correlated (r = - 0.22, p = 0.01) and types of habitat (r = - 0.20, p = 0.01). Significant habitat type productivity were observed in man-made pools (t = 3.881, P = 0.01163), rain pools, animal hoof prints, (t = - 4.332, P = 0.00749 in both short and long rainy season, whereas, during dry seasons habitat type productivity almost similar and have no significance difference. CONCLUSION The study found that different larval habitats had variable productivity in different seasons, and that physical and physicochemical features like ammonium and nitrate, as well as the distance between larval habitats and households, are related to larval production. As a result, vector control should take into account the seasonality of Anopheles larval habitat as well as the impact of pesticide application on larval source management.
Collapse
Affiliation(s)
- Arega Tsegaye
- College of Natural Science, Department of Biology, Jimma University, Jimma, Ethiopia.
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia.
| | - Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Dawit Hawaria
- School of Public Health, Hawassa University, Hawassa, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Ashenafi Abossie
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Arbaminch University, Arbaminch, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Hallelujah Getachew
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Sciences, College of Health Sciences, Arbaminch, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Kassahun Habtamu
- Department of Medical Laboratory Sciences, Menelik II College of Medicine and Health Science, Kotebe University of Education, Addis Ababa, Ethiopia
- Department of Microbial, Cellular & Molecular Biology, Addis Ababa University, Addis Ababa, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Teshome Degefa
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Xiaoming Wang
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Guofa Zhou
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| |
Collapse
|
6
|
Getachew H, Demissew A, Abossie A, Habtamu K, Wang X, Zhong D, Zhou G, Lee MC, Hemming-Schroeder E, Bradley L, Degefa T, Hawaria D, Tsegaye A, W Kazura J, Koepfli C, Yan G, Yewhalaw D. Asymptomatic and submicroscopic malaria infections in sugar cane and rice development areas of Ethiopia. Malar J 2023; 22:341. [PMID: 37940948 PMCID: PMC10634149 DOI: 10.1186/s12936-023-04762-5] [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: 03/14/2023] [Accepted: 10/22/2023] [Indexed: 11/10/2023] Open
Abstract
BACKGROUND Water resource development projects, such as dams and irrigation schemes, have a positive impact on food security and poverty reduction. However, such projects could increase prevalence of vector borne disease, such as malaria. This study investigate the impact of different agroecosystems and prevalence of malaria infection in Southwest Ethiopia. METHODS Two cross-sectional surveys were conducted in the dry and wet seasons in irrigated and non-irrigated clusters of Arjo sugarcane and Gambella rice development areas of Ethiopia in 2019. A total of 4464 and 2176 study participants from 1449 households in Arjo and 546 households in Gambella enrolled in the study and blood samples were collected, respectively. All blood samples were microscopically examined and a subset of microscopy negative blood samples (n = 2244) were analysed by qPCR. Mixed effect logistic regression and generalized estimating equation were used to determine microscopic and submicroscopic malaria infection and the associated risk factors, respectively. RESULTS Prevalence by microscopy was 2.0% (88/4464) in Arjo and 6.1% (133/2176) in Gambella. In Gambella, prevalence was significantly higher in irrigated clusters (10.4% vs 3.6%) than in non-irrigated clusters (p < 0.001), but no difference was found in Arjo (2.0% vs 2.0%; p = 0.993). On the other hand, of the 1713 and 531 samples analysed by qPCR from Arjo and Gambella the presence of submicroscopic infection was 1.2% and 12.8%, respectively. Plasmodium falciparum, Plasmodium vivax, and Plasmodium ovale were identified by qPCR in both sites. Irrigation was a risk factor for submicroscopic infection in both Arjo and Gambella. Irrigation, being a migrant worker, outdoor job, < 6 months length of stay in the area were risk factors for microscopic infection in Gambella. Moreover, school-age children and length of stay in the area for 1-3 years were significant predictors for submicroscopic malaria in Gambella. However, no ITN utilization was a predictor for both submicroscopic and microscopic infection in Arjo. Season was also a risk factor for microscopic infection in Arjo. CONCLUSION The study highlighted the potential importance of different irrigation practices impacting on submicroscopic malaria transmission. Moreover, microscopic and submicroscopic infections coupled with population movement may contribute to residual malaria transmission and could hinder malaria control and elimination programmes in the country. Therefore, strengthening malaria surveillance and control by using highly sensitive diagnostic tools to detect low-density parasites, screening migrant workers upon arrival and departure, ensuring adequate coverage and proper utilization of vector control tools, and health education for at-risk groups residing or working in such development corridors is needed.
Collapse
Affiliation(s)
- Hallelujah Getachew
- Department of Medical Laboratory Technology, Arbaminch College of Health Sciences, Arbaminch, Ethiopia.
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia.
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia.
| | - Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Ashenafi Abossie
- Department of Medical Laboratory Sciences, College of Medicine and Health Science, Arbaminch University, Arbaminch, Ethiopia
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Kassahun Habtamu
- Menelik II Medical & Health Science College, Addis Ababa, Ethiopia
- Department of Microbial, Cellular & Molecular Biology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Xiaoming Wang
- Program in Public Health, University of California at Irvine, Irvine, CA92697, USA
| | - Daibin Zhong
- Program in Public Health, University of California at Irvine, Irvine, CA92697, USA
| | - Guofa Zhou
- Program in Public Health, University of California at Irvine, Irvine, CA92697, USA
| | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, CA92697, USA
| | - Elizabeth Hemming-Schroeder
- Center for Vector Born Infectious Diseases (CVID), Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, USA
| | - Lauren Bradley
- Program in Public Health, University of California at Irvine, Irvine, CA92697, USA
| | - Teshome Degefa
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Dawit Hawaria
- School of Environmental Health, Hawassa University, Hawassa, Ethiopia
| | - Arega Tsegaye
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Department of Biology, College of Natural Science, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - James W Kazura
- Biomedical Research Case Western Reserve University, Cleveland, OH, USA
- Center for Global Health & Disease School of Medicine Case, Western Reserve University, Cleveland, OH, USA
| | - Cristian Koepfli
- Department of Biological Sciences 319 Galvin Life Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, USA
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, CA92697, USA
| | - Delenasaw Yewhalaw
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| |
Collapse
|
7
|
Jeang B, Lee MC, Embury P, Yewhalaw D, Narum D, King C, Tham WH, Kazura J, Yan G, Dent A. Serological Markers of Exposure to Plasmodium falciparum and Plasmodium vivax Infection in Southwestern Ethiopia. Am J Trop Med Hyg 2023; 108:871-881. [PMID: 37037443 PMCID: PMC10160885 DOI: 10.4269/ajtmh.22-0645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 01/22/2023] [Indexed: 04/12/2023] Open
Abstract
As malaria control and elimination efforts ramp up in Ethiopia, more sensitive tools for assessing exposure to coendemic Plasmodium falciparum and Plasmodium vivax are needed to accurately characterize malaria risk and epidemiology. Serological markers have been increasingly explored as cost-effective tools for measuring transmission intensity and evaluating intervention effectiveness. The objectives of this study were to evaluate the efficacy of a panel of 10 serological markers as a proxy for malaria exposure and to determine underlying risk factors of seropositivity. We conducted cross-sectional surveys in two sites of contrasting malaria transmission intensities in southwestern Ethiopia: Arjo in Oromia Region (low transmission) and Gambella in Gambella Regional State (moderate transmission). We measured antibody reactivity against six P. falciparum (AMA-1, CSP, EBA175RIII-V, MSP-142, MSP-3, RH2ab) and four P. vivax (DBPII[Sal1], EBP2, MSP-119, RBP2b) targets. We used mixed effects logistic regressions to assess predictors of seropositivity. Plasmodium spp. infection prevalence by quantitative polymerase chain reaction was 1.36% in Arjo and 10.20% in Gambella. Seroprevalence and antibody levels against all 10 antigens were higher in Gambella than in Arjo. We observed spatial heterogeneities in seroprevalence across Arjo and smaller variations across Gambella. Seroprevalence in both sites was lowest against PfCSP and highest against PfAMA-1, PfMSP-142, and PvMSPS-119. Male sex, age, and agricultural occupation were positively associated with seropositivity in Arjo; associations were less pronounced in Gambella. Our findings demonstrate that seroprevalence and antibody levels to specific Plasmodium antigens can be used to identify high-risk groups and geographical areas where interventions to reduce malaria transmission should be implemented.
Collapse
Affiliation(s)
- Brook Jeang
- Program in Public Health, University of California Irvine, Irvine, California
| | - Ming-Chieh Lee
- Program in Public Health, University of California Irvine, Irvine, California
| | - Paula Embury
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - David Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Christopher King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Wai-Hong Tham
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - James Kazura
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Guiyun Yan
- Program in Public Health, University of California Irvine, Irvine, California
| | - Arlene Dent
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| |
Collapse
|
8
|
Orondo PW, Wang X, Lee MC, Nyanjom SG, Atieli H, Ondeto BM, Ochwedo KO, Omondi CJ, Otambo WO, Zhou G, Zhong D, Githeko AK, Kazura JW, Yan G. Habitat Diversity, Stability, and Productivity of Malaria Vectors in Irrigated and Nonirrigated Ecosystems in Western Kenya. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:202-212. [PMID: 36334018 PMCID: PMC9835762 DOI: 10.1093/jme/tjac168] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Indexed: 06/16/2023]
Abstract
Several sub-Saharan African countries rely on irrigation for food production. This study examined the impact of environmental modifications resulting from irrigation on the ecology of aquatic stages of malaria vectors in a semi-arid region of western Kenya. Mosquito larvae were collected from irrigated and non-irrigated ecosystems during seasonal cross-sectional and monthly longitudinal studies to assess habitat availability, stability, and productivity of anophelines in temporary, semipermanent, and permanent habitats during the dry and wet seasons. The duration of habitat stability was also compared between selected habitats. Emergence traps were used to determine the daily production of female adult mosquitoes from different habitat types. Malaria vectors were morphologically identified and sibling species subjected to molecular analysis. Data was statistically compared between the two ecosystems. After aggregating the data, the overall malaria vector productivity for habitats in the two ecosystems was estimated. Immatures of the malaria vector (Anopheles arabiensis) Patton (Diptera: Culicidae) comprised 98.3% of the Anopheles in both the irrigated and non-irrigated habitats. The irrigated ecosystem had the most habitats, higher larval densities, and produced 85.8% of emerged adult females. These results showed that irrigation provided conditions that increased habitat availability, stability, and diversity, consequently increasing the An. arabiensis production and potential risk of malaria transmission throughout the year. The irrigated ecosystems increased the number of habitats suitable for Anopheles breeding by about 3-fold compared to non-irrigated ecosystems. These results suggest that water management in the irrigation systems of western Kenya would serve as an effective method for malaria vector control.
Collapse
Affiliation(s)
- Pauline Winnie Orondo
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
- International Center of Excellence for Malaria Research, Tom Mboya University, College of Maseno University, Homa Bay, Kenya
| | - Xiaoming Wang
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, USA
| | - Ming-Chieh Lee
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, USA
| | - Steven G Nyanjom
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Harrysone Atieli
- International Center of Excellence for Malaria Research, Tom Mboya University, College of Maseno University, Homa Bay, Kenya
| | - Benyl M Ondeto
- International Center of Excellence for Malaria Research, Tom Mboya University, College of Maseno University, Homa Bay, Kenya
| | - Kevin O Ochwedo
- International Center of Excellence for Malaria Research, Tom Mboya University, College of Maseno University, Homa Bay, Kenya
| | - Collince J Omondi
- International Center of Excellence for Malaria Research, Tom Mboya University, College of Maseno University, Homa Bay, Kenya
| | | | - Guofa Zhou
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, USA
| | - Daibin Zhong
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, USA
| | - Andrew K Githeko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - James W Kazura
- Center for Global Health & Diseases, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Guiyun Yan
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, USA
| |
Collapse
|
9
|
Hawaria D, Kibret S. Increased malaria incidence following irrigation practices in the Endorheic Rift Valley Basin of Sidama Region, Ethiopia. PLoS One 2023; 18:e0284247. [PMID: 37098016 PMCID: PMC10128979 DOI: 10.1371/journal.pone.0284247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 03/27/2023] [Indexed: 04/26/2023] Open
Abstract
BACKGROUND Water resource development practice such as irrigation is key to ensuring economic growth and food security in developing countries. However, unintended public health problems such as malaria linked to such development projects have been a concern. This study aimed to determine the impact of irrigation on malaria incidence and vector mosquito abundance in southern Ethiopia. METHODS Eight years' malaria morbidity data were extracted from the medical registers of health facilities in both irrigated and non-irrigated settings. Additionally, adult and larval malaria vector surveys were carried out in both irrigated and non-irrigated villages. The trend of malaria incidence, case distribution across age and sex, seasonality, parasite species proportion, and mosquito density were analyzed and compared between irrigated and non-irrigated villages. RESULTS The result showed that annual mean malaria incidence was 6.3 higher in the irrigated (95% CI: 0.7-33.6) than in the non-irrigated villages (95% CI: 1.2-20.6). Although a remarkable declining trend in malaria incidence was observed for four successive years (2013-2017), a significant resurgence between 2018 and 2020 was noted following the introduction of irrigation schemes. The densities of adult Anopheles mosquitoes were 15-fold higher in the irrigated compared to non-irrigated villages. Of the total potential mosquito-breeding habitats surveyed, the majority (93%) were from irrigated villages. CONCLUSION Higher malaria incidence, adult Anopheles density, and mosquito-breeding habitat were recorded in the irrigated villages compared to non-irrigated villages. These observations have important implications for the effectiveness of existing malaria interventions. Environmental management could help reduce the breeding of malaria vector mosquitoes around irrigation schemes.
Collapse
Affiliation(s)
- Dawit Hawaria
- School of Environmental Health, Hawassa University, Hawassa, Ethiopia
| | - Solomon Kibret
- California Department of Public Health, West Valley Mosquito and Vector Control District, Ontario, CA, United States of America
| |
Collapse
|
10
|
Yan G, Lee MC, Zhou G, Jiang AL, Degefa T, Zhong D, Wang X, Hemming-Schroeder E, Mukabana WR, Dent AE, King CL, Hsu K, Beeson J, Githure JI, Atieli H, Githeko AK, Yewhalaw D, Kazura JW. Impact of Environmental Modifications on the Ecology, Epidemiology, and Pathogenesis of Plasmodium falciparum and Plasmodium vivax Malaria in East Africa. Am J Trop Med Hyg 2022; 107:5-13. [PMID: 36228918 PMCID: PMC9662213 DOI: 10.4269/ajtmh.21-1254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 07/19/2022] [Indexed: 01/27/2023] Open
Abstract
Food insecurity, recurrent famine, and poverty threaten the health of millions of African residents. Construction of dams and rural irrigation schemes is key to solving these problems. The sub-Saharan Africa International Center of Excellence for Malaria Research addresses major knowledge gaps and challenges in Plasmodium falciparum and Plasmodium vivax malaria control and elimination in malaria-endemic areas of Kenya and Ethiopia where major investments in water resource development are taking place. This article highlights progress of the International Center of Excellence for Malaria Research in malaria vector ecology and behavior, epidemiology, and pathogenesis since its inception in 2017. Studies conducted in four field sites in Kenya and Ethiopia show that dams and irrigation increased the abundance, stability, and productivity of larval habitats, resulting in increased malaria transmission and a greater disease burden. These field studies, together with hydrological and malaria transmission modeling, enhance the ability to predict the impact of water resource development projects on vector larval ecology and malaria risks, thereby facilitating the development of optimal water and environmental management practices in the context of malaria control efforts. Intersectoral collaborations and community engagement are crucial to develop and implement cost-effective malaria control strategies that meet food security needs while controlling malaria burden in local communities.
Collapse
Affiliation(s)
- Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, California;,Address correspondence to Guiyun Yan, Program in Public Health, Room 3038, Hewitt Hall, University of California, Irvine, CA 92697-4050, E-mail: or James W. Kazura, Center for Global Health & Diseases, Case Western Reserve University, 2109 Adelbert Road Cleveland, OH 44106, E-mail:
| | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Guofa Zhou
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Ai-Ling Jiang
- Center for Hydrometeorology and Remote Sensing, Department of Civil and Environmental Engineering, University of California at Irvine, Irvine, California
| | - Teshome Degefa
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Daibin Zhong
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Xiaoming Wang
- Program in Public Health, University of California at Irvine, Irvine, California
| | | | | | - Arlene E. Dent
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Christopher L. King
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Kuolin Hsu
- Center for Hydrometeorology and Remote Sensing, Department of Civil and Environmental Engineering, University of California at Irvine, Irvine, California
| | - James Beeson
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | | | - Harrysone Atieli
- School of Public Health and Community Development, Maseno University, Kisumu, Kenya
| | - Andrew K. Githeko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Delenasaw Yewhalaw
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia;,Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - James W. Kazura
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio;,Address correspondence to Guiyun Yan, Program in Public Health, Room 3038, Hewitt Hall, University of California, Irvine, CA 92697-4050, E-mail: or James W. Kazura, Center for Global Health & Diseases, Case Western Reserve University, 2109 Adelbert Road Cleveland, OH 44106, E-mail:
| |
Collapse
|
11
|
Githure JI, Yewhalaw D, Atieli H, Hemming-Schroeder E, Lee MC, Wang X, Zhou G, Zhong D, King CL, Dent A, Mukabana WR, Degefa T, Hsu K, Githeko AK, Okomo G, Dayo L, Tushune K, Omondi CO, Taffese HS, Kazura JW, Yan G. Enhancing Malaria Research, Surveillance, and Control in Endemic Areas of Kenya and Ethiopia. Am J Trop Med Hyg 2022; 107:14-20. [PMID: 36228905 PMCID: PMC9662210 DOI: 10.4269/ajtmh.21-1303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 07/18/2022] [Indexed: 01/27/2023] Open
Abstract
Malaria control programs in Africa encounter daunting challenges that hinder progressive steps toward elimination of the disease. These challenges include widespread insecticide resistance in mosquito vectors, increasing outdoor malaria transmission, lack of vector surveillance and control tools suitable for outdoor biting vectors, weakness in malaria surveillance, and an inadequate number of skilled healthcare personnel. Ecological and epidemiological changes induced by environmental modifications resulting from water resource development projects pose additional barriers to malaria control. Cognizant of these challenges, our International Center of Excellence for Malaria Research (ICEMR) works in close collaboration with relevant government ministries and agencies to align its research efforts with the objectives and strategies of the national malaria control and elimination programs for the benefit of local communities. Our overall goal is to assess the impact of water resource development projects, shifting agricultural practices, and vector interventions on Plasmodium falciparum and P. vivax malaria in Kenya and Ethiopia. From 2017 to date, the ICEMR has advanced knowledge of malaria epidemiology, transmission, immunology, and pathogenesis, and developed tools to enhance vector surveillance and control, improved clinical malaria surveillance and diagnostic methods, and strengthened the capacity of local healthcare providers. Research findings from the ICEMR will inform health policy and strategic planning by ministries of health in their quest to sustain malaria control and achieve elimination goals.
Collapse
Affiliation(s)
| | - Delenasaw Yewhalaw
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia;,Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Harrysone Atieli
- School of Public Health and Community Development, Maseno University, Kisumu, Kenya
| | | | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Xiaoming Wang
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Guofa Zhou
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Daibin Zhong
- Program in Public Health, University of California at Irvine, Irvine, California
| | - Christopher L. King
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Arlene Dent
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio
| | | | - Teshome Degefa
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Kuolin Hsu
- Center for Hydrometeorology and Remote Sensing, Department of Civil and Environmental Engineering, University of California at Irvine, Irvine, California
| | - Andrew K. Githeko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Gordon Okomo
- Ministry of Health, Homa Bay County, Homa Bay, Kenya
| | - Lilyana Dayo
- Ministry of Health, Kisumu County, Kisumu, Kenya
| | - Kora Tushune
- Department of Health Management and Policy, Faculty of Public Health, Jimma University, Jimma, Ethiopia
| | | | - Hiwot S. Taffese
- National Malaria Program, Federal Ministry of Health, Addis Ababa, Ethiopia
| | - James W. Kazura
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio;,Address correspondence to Guiyun Yan, Program in Public Health, University of California at Irvine, Irvine, CA, E-mail: or James Kazura, Center for Global Health & Diseases, Case Western Reserve University, Cleveland, OH, E-mail:
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, California;,Address correspondence to Guiyun Yan, Program in Public Health, University of California at Irvine, Irvine, CA, E-mail: or James Kazura, Center for Global Health & Diseases, Case Western Reserve University, Cleveland, OH, E-mail:
| |
Collapse
|
12
|
Otambo WO, Onyango PO, Wang C, Olumeh J, Ondeto BM, Lee MC, Atieli H, Githeko AK, Kazura J, Zhong D, Zhou G, Githure J, Ouma C, Yan G. Influence of landscape heterogeneity on entomological and parasitological indices of malaria in Kisumu, Western Kenya. Parasit Vectors 2022; 15:340. [PMID: 36167549 PMCID: PMC9516797 DOI: 10.1186/s13071-022-05447-9] [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: 05/09/2022] [Accepted: 08/22/2022] [Indexed: 12/04/2022] Open
Abstract
Background Identification and characterization of larval habitats, documentation of Anopheles spp. composition and abundance, and Plasmodium spp. infection burden are critical components of integrated vector management. The present study aimed to investigate the effect of landscape heterogeneity on entomological and parasitological indices of malaria in western Kenya. Methods A cross-sectional entomological and parasitological survey was conducted along an altitudinal transect in three eco-epidemiological zones: lakeshore along the lakeside, hillside, and highland plateau during the wet and dry seasons in 2020 in Kisumu County, Kenya. Larval habitats for Anopheles mosquitoes were identified and characterized. Adult mosquitoes were sampled using pyrethrum spray catches (PSC). Finger prick blood samples were taken from residents and examined for malaria parasites by real-time PCR (RT-PCR). Results Increased risk of Plasmodium falciparum infection was associated with residency in the lakeshore zone, school-age children, rainy season, and no ITNs (χ2 = 41.201, df = 9, P < 0.0001). Similarly, lakeshore zone and the rainy season significantly increased Anopheles spp. abundance. However, house structures such as wall type and whether the eave spaces were closed or open, as well as the use of ITNs, did not affect Anopheles spp. densities in the homes (χ2 = 38.695, df = 7, P < 0.0001). Anopheles funestus (41.8%) and An. arabiensis (29.1%) were the most abundant vectors in all zones. Sporozoite prevalence was 5.6% and 3.2% in the two species respectively. The lakeshore zone had the highest sporozoite prevalence (4.4%, 7/160) and inoculation rates (135.2 infective bites/person/year). High larval densities were significantly associated with lakeshore zone and hillside zones, animal hoof prints and tire truck larval habitats, wetland and pasture land, and the wet season. The larval habitat types differed significantly across the landscape zones and seasonality (χ2 = 1453.044, df = 298, P < 0.0001). Conclusion The empirical evidence on the impact of landscape heterogeneity and seasonality on vector densities, parasite transmission, and Plasmodium infections in humans emphasizes the importance of tailoring specific adaptive environmental management interventions to specific landscape attributes to have a significant impact on transmission reduction. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-022-05447-9.
Collapse
Affiliation(s)
- Wilfred Ouma Otambo
- Department of Zoology, Maseno University, Kisumu, Kenya. .,International Centre of Excellence for Malaria Research, Tom Mboya University College-University of California Irvine Joint Lab, Homa Bay, Kenya.
| | | | - Chloe Wang
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Julius Olumeh
- School of Natural and Environmental Science, Newcastle University, Newcastle, UK
| | - Benyl M Ondeto
- International Centre of Excellence for Malaria Research, Tom Mboya University College-University of California Irvine Joint Lab, Homa Bay, Kenya.,Department of Biology, University of Nairobi, Nairobi, Kenya
| | - Ming-Chieh Lee
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Harrysone Atieli
- International Centre of Excellence for Malaria Research, Tom Mboya University College-University of California Irvine Joint Lab, Homa Bay, Kenya
| | - Andrew K Githeko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - James Kazura
- Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.,Centre for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Daibin Zhong
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Guofa Zhou
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - John Githure
- International Centre of Excellence for Malaria Research, Tom Mboya University College-University of California Irvine Joint Lab, Homa Bay, Kenya
| | - Collins Ouma
- Department of Biomedical Sciences and Technology, Maseno University, Kisumu, Kenya
| | - Guiyun Yan
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| |
Collapse
|
13
|
Freitas Silva SO, de Mello CF, Machado SL, Leite PJ, Alencar J. Interaction of Haemagogus leucocelaenus (Diptera: Culicidae) and Other Mosquito Vectors in a Forested Area, Rio de Janeiro, Brazil. Trop Med Infect Dis 2022; 7:tropicalmed7060094. [PMID: 35736973 PMCID: PMC9228385 DOI: 10.3390/tropicalmed7060094] [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: 05/10/2022] [Revised: 05/31/2022] [Accepted: 06/05/2022] [Indexed: 12/04/2022] Open
Abstract
The yellow fever (YF) virus has been detected throughout Brazil, with the occurrence of human cases, cyclic epizootics, and its isolation from Haemagogus janthinomys and Hg. leucocelaenus. We assessed the seasonal occurrence, egg abundancy, and oviposition interaction of mosquito vector species captured at a Private Natural Heritage Reserve in the Atlantic Forest biome. A total of 2943 eggs and 1538 mosquito larvae were collected from which 1231 belonged to entomologically important species. Ovitraps were used to collect immature mosquitoes from September 2019 to January 2021. The Mann–Whitney test was used to assess the differences in the abundance of eggs between rainy and dry seasons. Kruskal–Wallis and Dunn’s post hoc tests were used to evaluate the significance of the differences in the number of individuals from vector species. The highest percentage of mosquito vector eggs were collected during the rainy season, from December to February. Most eggs recovered from ovitraps belonged to the species Hg. leucocelaenus, representing 85% of all mosquito eggs identified. The other species had lower abundances and percentages: Aedes terrens (7%), Haemagogus janthinomys (5%) and Aedes albopictus (3%). The species that shared breeding sites with a higher frequency were Hg. leucocelaenus and Hg. janthinomys, with a statistically positive correlation (ρ = 0.74). This finding suggests that maybe the presence of Hg. leucocelaenus eggs acted as an attractant for Hg. janthinomys or vice versa. An understanding of mosquito oviposition behavior is necessary for the development of surveillance and control approaches directed against specific pathogen vectors of medical and veterinary importance.
Collapse
Affiliation(s)
- Shayenne Olsson Freitas Silva
- Diptera Laboratory, Oswaldo Cruz Institute (FIOCRUZ), Av. Brazil 4365, Manguinhos, Rio de Janeiro 21040-360, Brazil; (S.O.F.S.); (C.F.d.M.); (P.J.L.)
- Postgraduate Program in Tropical Medicine, Oswaldo Cruz Institute (FIOCRUZ), Av. Brazil 4365, Manguinhos, Rio de Janeiro 21040-360, Brazil
| | - Cecilia Ferreira de Mello
- Diptera Laboratory, Oswaldo Cruz Institute (FIOCRUZ), Av. Brazil 4365, Manguinhos, Rio de Janeiro 21040-360, Brazil; (S.O.F.S.); (C.F.d.M.); (P.J.L.)
- Postgraduate Program in Animal Biology, Institute of Biology, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro 23890-000, Brazil
| | - Sergio Lisboa Machado
- Laboratory of Molecular Diagnosis and Hematology, Federal University of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil;
| | - Paulo José Leite
- Diptera Laboratory, Oswaldo Cruz Institute (FIOCRUZ), Av. Brazil 4365, Manguinhos, Rio de Janeiro 21040-360, Brazil; (S.O.F.S.); (C.F.d.M.); (P.J.L.)
| | - Jeronimo Alencar
- Diptera Laboratory, Oswaldo Cruz Institute (FIOCRUZ), Av. Brazil 4365, Manguinhos, Rio de Janeiro 21040-360, Brazil; (S.O.F.S.); (C.F.d.M.); (P.J.L.)
- Correspondence:
| |
Collapse
|
14
|
Chanyalew T, Natea G, Amenu D, Yewhalaw D, Simma EA. Composition of mosquito fauna and insecticide resistance status of Anopheles gambiae sensu lato in Itang special district, Gambella, Southwestern Ethiopia. Malar J 2022; 21:125. [PMID: 35436961 PMCID: PMC9014582 DOI: 10.1186/s12936-022-04150-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 04/04/2022] [Indexed: 11/10/2022] Open
Abstract
Background Anopheles arabiensis, member species of the Anopheles gambiae complex, is the primary vector of malaria and is widely distributed in Ethiopia. Anopheles funestus, Anopheles pharoensis and Anopheles nili are secondary vectors occurring with limited distribution in the country. Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) are pillars for the interventions against malaria control and elimination efforts in Ethiopia. However, the emergence and widespread of insecticide resistance in An. gambiae sensu lato (s.l.), might compromise the control efforts of the country. The aim of this study was to investigate composition of mosquito fauna and insecticide resistance status of An. gambiae s.l. in Itang special district ( woreda), Gambella, southwestern Ethiopia. Methods Adult mosquitoes were sampled from September 2020 to February 2021 using the CDC light trap and pyrethrum spray catch (PSC). CDC light traps were placed in three selected houses for two consecutive days per month to collect mosquitoes indoor and outdoor from 6:00 P.M. to 06:00 A.M. and PSC was used to collect indoor resting mosquitoes from ten selected houses once in a month from October 2020 to February 2021. Moreover, mosquito larvae were also collected from different breeding sites and reared to adults to assess susceptibility status of populations of An. gambiae s.l. in the study area. Susceptibility tests were conducted on two to three days old non blood fed female An. gambiae s.l. using insecticide impregnated papers with deltamethrin (0.05%), alpha-cypermethrin (0.05%), propoxur (0.1%), pirimiphos-methyl (0.25%) and bendiocarb (0.1%) following World Health Organization (WHO) standard susceptibility test procedure. Molecular diagnostics were done for the identification of member species of An. gambiae s.l. and detection of knockdown resistance (kdr) allele using species specific polymerase chain reaction (PCR) and allele specific PCR. Results In total, 468 adult mosquitoes were collected from different houses. Culex mosquitoes were the most dominant (80.4%) followed by Anopheles mosquitoes. Three species of Anopheles (Anopheles coustani, An. pharoensis, and An. gambiae s.l.) were identified, of which An. coustani was the dominant (8.1%) species. Higher number of mosquitoes (231) were collected outdoor by CDC light traps. Out of 468 adult mosquitoes, 294 were blood fed, 46 were half-gravid and gravid whereas the remaining 128 were unfed. WHO bioassay tests revealed that the populations of An. gambiae s.l. in the study area are resistant against alpha-cypermethrin and deltamethrin, but susceptible to bendiocarb, pirimiphos-methyl and propoxur. Of the total 86 An. gambiae s.l. specimens assayed, 79 (92%) successfully amplified and identified as An. arabiensis. West African kdr (L1014F) mutation was detected with high kdr allele frequency ranging from 67 to 88%. Conclusion The detection of target site mutation, kdr L1014F allele, coupled with the phenotypic resistance against alpha-cypermethrin and deltamethrin call for continuous resistance monitoring.
Collapse
|
15
|
Demissew A, Animut A, Kibret S, Tsegaye A, Hawaria D, Degefa T, Getachew H, Lee MC, Yan G, Yewhalaw D. Evidence of pyrethroid resistance in Anopheles amharicus and Anopheles arabiensis from Arjo-Didessa irrigation scheme, Ethiopia. PLoS One 2022; 17:e0261713. [PMID: 35030201 PMCID: PMC8759678 DOI: 10.1371/journal.pone.0261713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/08/2021] [Indexed: 11/18/2022] Open
Abstract
Background Indoor residual spraying and insecticide-treated nets are among the key malaria control intervention tools. However, their efficacy is declining due to the development and spread of insecticide resistant vectors. In Ethiopia, several studies reported resistance of An. arabiensis to multiple insecticide classes. However, such data is scarce in irrigated areas of the country where insecticides, pesticides and herbicides are intensively used. Susceptibility of An. gambiae s.l. to existing and new insecticides and resistance mechanisms were assessed in Arjo-Didessa sugarcane plantation area, southwestern Ethiopia. Methods Adult An. gambiae s.l. reared from larval/pupal collections of Arjo-Didessa sugarcane irrigation area and its surrounding were tested for their susceptibility to selected insecticides. Randomly selected An. gambiae s.l. (dead and survived) samples were identified to species using species-specific polymerase chain reaction (PCR) and were further analyzed for the presence of knockdown resistance (kdr) alleles using allele-specific PCR. Results Among the 214 An. gambiae s.l. samples analyzed by PCR, 89% (n = 190) were An. amharicus and 9% (n = 20) were An. arabiensis. Mortality rates of the An. gambiae s.l. exposed to deltamethrin and alphacypermethrin were 85% and 86.8%, respectively. On the other hand, mortalities against pirmiphos-methyl, bendiocarb, propoxur and clothianidin were 100%, 99%, 100% and 100%, respectively. Of those sub-samples (An. amharicus and An. arabiensis) examined for presence of kdr gene, none of them were found to carry the L1014F (West African) allelic mutation. Conclusion Anopheles amharicus and An. arabiensis from Arjo-Didessa sugarcane irrigation area were resistant to pyrethroids which might be synergized by extensive use of agricultural chemicals. Occurrence of pyrethroid resistant malaria vectors could challenge the ongoing malaria control and elimination program in the area unless resistance management strategies are implemented. Given the resistance of An. amharicus to pyrethroids, its behavior and vectorial capacity should be further investigated.
Collapse
Affiliation(s)
- Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- * E-mail: ,
| | - Abebe Animut
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Solomon Kibret
- Program in Public Health, University of California at Irvine, Irvine, California, United States of America
| | - Arega Tsegaye
- Department of Biology, College of Natural Science, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Dawit Hawaria
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
- Yirgalem Hospital Medical College, Yirgalem, Ethiopia
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
| | - Teshome Degefa
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
| | - Hallelujah Getachew
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Sciences, Arbaminch College of Health Sciences, Arba Minch, Ethiopia
| | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, California, United States of America
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, California, United States of America
| | - Delenasaw Yewhalaw
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
| |
Collapse
|
16
|
Review of Anopheles Mosquito Species, Abundance, and Distribution in Ethiopia. J Trop Med 2021; 2021:6726622. [PMID: 34603455 PMCID: PMC8486561 DOI: 10.1155/2021/6726622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/03/2021] [Indexed: 11/17/2022] Open
Abstract
Background Malaria is a major mosquito-borne disease in Ethiopia, and it is one of the leading causes of morbidity and mortality. Plasmodium falciparum and P. vivax are the two malaria-causing parasitic species commonly known to cause human malaria in Ethiopia. To better manage and control vectors transmitting malaria parasites, the abundance, distribution, and updated annotated list of Anopheles species present in Ethiopia are very important. Methods In order to compile a list of the species recorded in Ethiopia, 33 original research articles were collected. This work gives an updated list of Anopheles mosquito species in Ethiopia and their abundance, distribution, and composition. Results According to this review, 110305 Anopheles mosquitoes were collected and 35 Anopheles species were recorded in different parts of Ethiopia. A. arabiensis was the most abundant when compared to other species, whereas A. maculipalpis and A. wilsonii were the least abundant species. The most abundant Anopheles species was recorded in central and the least abundant, from eastern Ethiopia. The second, third, and fourth abundant species were also collected from southern, northern, and western parts of Ethiopia.
Collapse
|
17
|
Doumbe-Belisse P, Kopya E, Ngadjeu CS, Sonhafouo-Chiana N, Talipouo A, Djamouko-Djonkam L, Awono-Ambene HP, Wondji CS, Njiokou F, Antonio-Nkondjio C. Urban malaria in sub-Saharan Africa: dynamic of the vectorial system and the entomological inoculation rate. Malar J 2021; 20:364. [PMID: 34493280 PMCID: PMC8424958 DOI: 10.1186/s12936-021-03891-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/20/2021] [Indexed: 12/11/2022] Open
Abstract
Sub-Saharan Africa is registering one of the highest urban population growth across the world. It is estimated that over 75% of the population in this region will be living in urban settings by 2050. However, it is not known how this rapid urbanization will affect vector populations and disease transmission. The present study summarizes findings from studies conducted in urban settings between the 1970s and 2020 to assess the effects of urbanization on the entomological inoculation rate pattern and anopheline species distribution. Different online databases such as PubMed, ResearchGate, Google Scholar, Google were screened. A total of 90 publications were selected out of 1527. Besides, over 200 additional publications were consulted to collate information on anopheline breeding habitats and species distribution in urban settings. The study confirms high malaria transmission in rural compared to urban settings. The study also suggests that there had been an increase in malaria transmission in most cities after 2003, which could also be associated with an increase in sampling, resources and reporting. Species of the Anopheles gambiae complex were the predominant vectors in most urban settings. Anopheline larvae were reported to have adapted to different aquatic habitats. The study provides updated information on the distribution of the vector population and the dynamic of malaria transmission in urban settings. The study also highlights the need for implementing integrated control strategies in urban settings.
Collapse
Affiliation(s)
- P Doumbe-Belisse
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun.,Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - E Kopya
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun.,Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - C S Ngadjeu
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun.,Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - N Sonhafouo-Chiana
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun.,Faculty of Health Sciences, University of Buea, Cameroon, P.O. Box 63, Buea, Cameroon
| | - A Talipouo
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun.,Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - L Djamouko-Djonkam
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun.,Faculty of Sciences, University of Dschang Cameroon, P.O. Box 67, Dschang, Cameroon
| | - H P Awono-Ambene
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun
| | - C S Wondji
- Vector Group Liverpool School of Tropical Medicine Pembroke Place, Liverpool, L3 5QA, UK
| | - F Njiokou
- Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - C Antonio-Nkondjio
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination Pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroun. .,Vector Group Liverpool School of Tropical Medicine Pembroke Place, Liverpool, L3 5QA, UK.
| |
Collapse
|
18
|
Fang A, Sun Y, Feng D, Ma M, Xu Z, Zhang T, Shi F. Flower-like gold nanoparticles labeled and silver deposition rapid vertical flow technology for highly sensitive detection of Brucella antibodies. Analyst 2021; 146:5362-5368. [PMID: 34337622 DOI: 10.1039/d1an01075a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To prevent the transmission of brucellosis, rapid vertical flow technology (RVFT) was developed to detect brucellosis antibodies. To improve the sensitivity of the technique, lipopolysaccharides (LPS) were purified and used to detect brucellosis antibodies. To improve the sensitivity of serum antibody detection, a single multifunctional buffer was established in whole blood and other biological samples, and the advantages of the lateral flow immunoassay were retained. Flower-like gold nanoparticles were applied to RVFT for the first time. In this study, silver ions were catalyzed by flower-like gold nanoparticles into metal silver deposited on the surface of gold nanoparticles for the first time, which not only increased the particle size of gold nanoparticles, but also showed a more distinguishable black color on the test zone, further improving the sensitivity of RVFT. Standard Brucella-positive serum (containing Brucella antibody at 4000 IU mL-1) could be detected in this system even for a dilution factor of 2 × 10-3. The detection limit was 2 IU mL-1. RVFT can effectively avoid the false negative phenomenon in lateral flow immunoassay. RVFT is simple to operate, with a short reaction time, 2-3 minutes visible to the naked eye, without any equipment. Because it is very important to control the brucellosis epidemic, this approach has great application prospects in basic medical units and for veterinarians.
Collapse
Affiliation(s)
- Ashe Fang
- College of Life Sciences, Shihezi University, Shihezi, Xinjiang 832003, China.
| | | | | | | | | | | | | |
Collapse
|
19
|
Awosolu OB, Yahaya ZS, Farah Haziqah MT. Prevalence, Parasite Density and Determinants of Falciparum Malaria Among Febrile Children in Some Peri-Urban Communities in Southwestern Nigeria: A Cross-Sectional Study. Infect Drug Resist 2021; 14:3219-3232. [PMID: 34434052 PMCID: PMC8380643 DOI: 10.2147/idr.s312519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/27/2021] [Indexed: 11/23/2022] Open
Abstract
Background Malaria remains a serious public health problem worldwide, particularly in tropical and subtropical regions, including Nigeria. This study investigates the prevalence, parasite density and determinants of malaria among symptomatic children in some peri-urban communities in southwestern Nigeria. Methods This was a randomized cross-sectional and hospital-based study. The standard method of microscopy was employed. Thick and thin films were prepared and viewed under a light microscope to identify and quantify malaria parasites. A well-structured and pre-tested questionnaire was used to obtain the subject’s information on the demographic, socio-economic and environmental variables. Results A total of 380 (71.7%) participants were infected with Plasmodium falciparum with a mean parasite density of 1857.11 parasite/µL of blood. Malaria prevalence and mean parasite density were significantly higher among male compared to their female counterparts [80.3% vs 61.4% and 2026.46 vs 1619.63 parasite/µL of blood]. Similarly, age group ≤5 years had the highest malaria prevalence (92.2%) and mean parasite density (2031.66 parasite/µL of blood) than other age groups (AOR 2.281, 95% CI: 1.187–4.384, P < 0.05). The multivariate logistic analysis showed that malaria disease is significantly associated with having mother with no formal education (AOR 12.235, 95% CI: 3.253–46.021, P < 0.05), having well and river as a major source of household water supply (AOR 13.810, 95% CI: 3.012–63.314, P < 0.05 vs AOR 5.639, 95% CI: 1.455–21.853, P < 0.05) and presence of stagnant water around home (AOR 5.22, 95% CI: 2.921–9.332, P < 0.05). Furthermore, protective factors observed include ownership of mosquito bed net (AOR 0.474, 95% CI: 0.223–1.008, P < 0.05) and distance of home to hospital (AOR 0.279, 95% CI: 0.158–0.493, P < 0.05). Conclusion Malaria remains a serious public health problem in the study area. Adopting integrated malaria control measures including educating parents on malaria prevention and control strategies, distributing mosquito bed nets, and establishing larvae source management program is highly imperative.
Collapse
Affiliation(s)
- Oluwaseun Bunmi Awosolu
- School of Biological Sciences, Universiti Sains Malaysia, Penang, 11800 USM, Malaysia.,Department of Biology, Federal University of Technology, Akure, Nigeria
| | - Zary Shariman Yahaya
- School of Biological Sciences, Universiti Sains Malaysia, Penang, 11800 USM, Malaysia
| | | |
Collapse
|
20
|
Jiang AL, Lee MC, Zhou G, Zhong D, Hawaria D, Kibret S, Yewhalaw D, Sanders BF, Yan G, Hsu K. Predicting distribution of malaria vector larval habitats in Ethiopia by integrating distributed hydrologic modeling with remotely sensed data. Sci Rep 2021; 11:10150. [PMID: 33980945 PMCID: PMC8115507 DOI: 10.1038/s41598-021-89576-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 04/16/2021] [Indexed: 02/03/2023] Open
Abstract
Larval source management has gained renewed interest as a malaria control strategy in Africa but the widespread and transient nature of larval breeding sites poses a challenge to its implementation. To address this problem, we propose combining an integrated high resolution (50 m) distributed hydrological model and remotely sensed data to simulate potential malaria vector aquatic habitats. The novelty of our approach lies in its consideration of irrigation practices and its ability to resolve complex ponding processes that contribute to potential larval habitats. The simulation was performed for the year of 2018 using ParFlow-Common Land Model (CLM) in a sugarcane plantation in the Oromia region, Ethiopia to examine the effects of rainfall and irrigation. The model was calibrated using field observations of larval habitats to successfully predict ponding at all surveyed locations from the validation dataset. Results show that without irrigation, at least half of the area inside the farms had a 40% probability of potential larval habitat occurrence. With irrigation, the probability increased to 56%. Irrigation dampened the seasonality of the potential larval habitats such that the peak larval habitat occurrence window during the rainy season was extended into the dry season. Furthermore, the stability of the habitats was prolonged, with a significant shift from semi-permanent to permanent habitats. Our study provides a hydrological perspective on the impact of environmental modification on malaria vector ecology, which can potentially inform malaria control strategies through better water management.
Collapse
Affiliation(s)
- Ai-Ling Jiang
- Department of Civil and Environmental Engineering, University of California Irvine, Irvine, CA, USA.
| | - Ming-Chieh Lee
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Guofa Zhou
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Daibin Zhong
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Dawit Hawaria
- Yirgalem Hospital Medical College, Yirgalem, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Solomon Kibret
- Program in Public Health, University of California Irvine, Irvine, CA, USA
| | - Delenasaw Yewhalaw
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Sciences, Institute of Health, Jimma University, Jimma, Ethiopia
| | - Brett F Sanders
- Department of Civil and Environmental Engineering, University of California Irvine, Irvine, CA, USA
- Department of Urban Planning and Public Policy, University of California Irvine, Irvine, CA, USA
| | - Guiyun Yan
- Program in Public Health, University of California Irvine, Irvine, CA, USA.
| | - Kuolin Hsu
- Department of Civil and Environmental Engineering, University of California Irvine, Irvine, CA, USA.
| |
Collapse
|
21
|
Hawaria D, Kibret S, Demissew A, Tsegaye A, Bitew D, Yan G, Yewhalaw D. Survivorship of Anopheles gambiae sensu lato in irrigated sugarcane plantation scheme in Ethiopia. Parasit Vectors 2021; 14:142. [PMID: 33676562 PMCID: PMC7936430 DOI: 10.1186/s13071-021-04630-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 02/06/2021] [Indexed: 01/16/2023] Open
Abstract
Background To ensure food security, sub-Saharan Africa has initiated massive water resource development projects, such as irrigated agriculture, in recent years. However, such environmental modifications affect the survivorship and development of mosquitoes, which are vectors of different diseases. This study aimed at determining the effects of irrigation practices on development and survivorship of Anopheles gambiae s.l. in Ethiopia. Methods A life table experiment was conducted to examine the effect of environmental modification on survivorship of both immature and adult An. gambiae s.l. in irrigated and non-irrigated areas. The pupation rate and development time of the immatures and adult longevity and fecundity were compared between the two settings. Results The estimated mean survival time of female An. gambiae s.l. in the irrigated and non-irrigated areas was 37.9 and 31.3 days, respectively. A survival analysis showed that adult females of An. gambiae s.l. placed in an irrigated area lived significantly longer than those in a non-irrigated area (χ2 = 18.3, df = 1, P <0.001), and An. gambiae s.l. females lived significantly longer than males in both areas (P < 0.001). Conclusions Adult An. gambiae s.l. survivorship was found to be enhanced in the irrigated area compared to non-irrigated area. Longer survival of adult mosquitoes in irrigated areas could have important implications for vectorial capacity and hence malaria transmission.![]()
Collapse
Affiliation(s)
- Dawit Hawaria
- Yirgalem Hospital Medical College, Yirgalem, Ethiopia. .,Department of Medical Laboratory Sciences and Pathology, Institute of Health, Jimma University, Jimma, Ethiopia. .,Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia.
| | - Solomon Kibret
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia
| | - Arega Tsegaye
- Department of Biology, Collage of Natural Science, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Denekew Bitew
- Department of Statistics, College of Science, Bahir Dar University, Bahir Dar, Ethiopia
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Delenasaw Yewhalaw
- Department of Medical Laboratory Sciences and Pathology, Institute of Health, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| |
Collapse
|
22
|
Shayo FK, Nakamura K, Al-Sobaihi S, Seino K. Is the source of domestic water associated with the risk of malaria infection? Spatial variability and a mixed-effects multilevel analysis. Int J Infect Dis 2020; 104:224-231. [PMID: 33359948 DOI: 10.1016/j.ijid.2020.12.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 12/18/2020] [Accepted: 12/20/2020] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND There is a dearth of information on the relationship between domestic water source and malaria infection in malaria-endemic regions such as Tanzania. This study examined the geospatial variability and association between domestic water source and malaria prevalence in Tanzania. METHODS We analyzed data from a sample of 6707 children, aged 6-59 months, from the 2017 Tanzania Malaria Indicator Survey. The outcome variable was the result of malaria testing (positive or negative) and the main explanatory variable was domestic water source (piped or non-piped). Random effect variables were administrative region and geographical zone. ArcGIS 10.7 was used to create geospatial distribution maps. A STATA MP 14.0 was used to fit a mixed-effects multilevel logistic regression to examine the factors associated with malaria prevalence. RESULTS The prevalence of malaria and non-piped domestic water source was respectively 7.3% and 59.6%. The regions and zones with a higher prevalence of malaria also had a higher percentage of non-piped water. There was a statistically significant variation in the risk of malaria across the regions (variance = 1.27; 95% CI, 0.40-4.07) and zones (variance = 4.75; 95% CI, 1.46-15.46). The final fixed-effects model showed that non-piped domestic water was significantly associated with malaria prevalence (adjusted odds ratio (AOR) = 2.18; 95% CI, 1.64-2.89; P < 0.001). CONCLUSIONS A non-piped source of domestic water was independently associated with positive testing for malaria. Moreover, regions with a high percentage of non-piped domestic water had a correspondingly high prevalence of malaria.
Collapse
Affiliation(s)
- Festo Kasmir Shayo
- Department of Global Health Entrepreneurship, Division of Public Health, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan; Muhimbili University of Health and Allied Sciences, P.O Box 65001, Dar es Salaam, Tanzania
| | - Keiko Nakamura
- Department of Global Health Entrepreneurship, Division of Public Health, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
| | - Saber Al-Sobaihi
- Department of Global Health Entrepreneurship, Division of Public Health, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Kaoruko Seino
- Department of Global Health Entrepreneurship, Division of Public Health, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| |
Collapse
|
23
|
Demissew A, Hawaria D, Kibret S, Animut A, Tsegaye A, Lee MC, Yan G, Yewhalaw D. Impact of sugarcane irrigation on malaria vector Anopheles mosquito fauna, abundance and seasonality in Arjo-Didessa, Ethiopia. Malar J 2020; 19:344. [PMID: 32962693 PMCID: PMC7510110 DOI: 10.1186/s12936-020-03416-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/10/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Despite extensive irrigation development in Ethiopia, limited studies assessed the impact of irrigation on malaria vector mosquito composition, abundance and seasonality. This study aimed to evaluate the impact of sugarcane irrigation on species composition, abundance and seasonality of malaria vectors. METHODS Adult Anopheles mosquitoes were collected using CDC light traps from three irrigated and three non-irrigated clusters in and around Arjo-Didessa sugarcane irrigation scheme in southwestern Ethiopia. Mosquitoes were surveyed in four seasons: two wet and two dry, in 2018 and 2019. Mosquito species composition, abundance and seasonality were compared between irrigated and non-irrigated clusters. Anopheles mosquitoes were sorted out to species using morphological keys and molecular techniques. Chi square was used to test the relationships between Anopheles species occurrence, and environmental and seasonal parameters. RESULTS Overall, 2108 female Anopheles mosquitoes comprising of six species were collected. Of these, 92.7% (n = 1954) were from irrigated clusters and 7.3% (n = 154) from the non-irrigated. The Anopheles gambiae complex was the most abundant (67.3%) followed by Anopheles coustani complex (25.3%) and Anopheles pharoensis (5.7%). PCR-based identification revealed that 74.7% (n = 168) of the An. gambiae complex were Anopheles arabiensis and 22.7% (n = 51) Anopheles amharicus. The density of An. gambiae complex (both indoor and outdoor) was higher in irrigated than non-irrigated clusters. The overall anopheline mosquito abundance during the wet seasons (87.2%; n = 1837) was higher than the dry seasons (12.8%; n = 271). CONCLUSION The ongoing sugarcane irrigation activities in Arjo-Didessa created conditions suitable for malaria transmitting Anopheles species diversity and abundance. This could drive malaria transmission in Arjo-Didessa and its environs in both dry and wet seasons. Currently practiced malaria vector interventions need to be strengthened by including larval source management to reduce vector abundance in the irrigated areas.
Collapse
Affiliation(s)
- Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia. .,Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Dawit Hawaria
- Yirgalem Hospital Medical College, Yirgalem, Ethiopia.,School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Solomon Kibret
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Abebe Animut
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Arega Tsegaye
- College of Natural Science, Department of Biology, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Ming-Cheih Lee
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| |
Collapse
|
24
|
Djègbè I, Zinsou M, Dovonou EF, Tchigossou G, Soglo M, Adéoti R, Gbaguidi B, Atoyebi S, Chandre F, Akogbéto M, Lines J, Djouaka R. Minimal tillage and intermittent flooding farming systems show a potential reduction in the proliferation of Anopheles mosquito larvae in a rice field in Malanville, Northern Benin. Malar J 2020; 19:333. [PMID: 32928223 PMCID: PMC7491134 DOI: 10.1186/s12936-020-03406-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 09/04/2020] [Indexed: 12/05/2022] Open
Abstract
Background Irrigation systems have been identified as one of the factors promoting malaria disease around agricultural farms in sub-Saharan Africa. However, if improved water management strategy is adopted during rice cultivation, it may help to reduce malaria cases among human population living around rice fields. This study aimed to assess the impact of the different irrigation practices on malaria transmission, as well as to evaluate the water management system that will best mitigate malaria transmission in Malanville, Benin. Methods Knowledge, Attitude and Practice (KAP) study was conducted on 104 households staying on and around the rice fields in Malanville. The study focused on the frequency of mosquito bites and preventive measures against malaria as well as soil preparation and rice planting methods. Mosquito larvae density was assessed in different water management system: continuous flooding (CF) or intermittent flooding (IF), deep tillage (DT) or minimal tillage (MT) and normal levelling (NL) or abnormal levelling (AL) in an experimental hut set-up. Larvae were collected using dipping methods and their density was determined. Results Three tillage systems, which include the use of tiller, plow and hoe, were identified on the rice field. Continuous flooding was the only irrigation system used by farmers. Retrospective data from Malanville Health Centre revealed higher malaria cases during rice production season, which was also confirmed by field participants. The density of Anopheles larvae was reduced by 80.8%, 30.8% and 40.7% (P = 0.000) during transplanting, tillering and maturation periods, respectively with intermittent flooding compared to continuous flooding. In addition, a clear reduction of larva density was observed with both intermittent flooding systems applied to minimal tillage (MT + IF + NL) and intermittent flooding applied to deep tillage (DT + IF + AL), showing that intermittent flooding could reduce the abundance of malaria vector in rice fields. Conclusion Recommending intermittent flooding technology for rice cultivation may not only be useful for water management but could also be an intentional strategy to control mosquitoes vector-borne diseases around rice farms.
Collapse
Affiliation(s)
- Innocent Djègbè
- National University of Sciences, Technologies, Engineering and Mathematics, Ecole Normale Supérieure de Natitingou, BP 72, Natitingou, Benin.
| | - Merdie Zinsou
- Laboratoire d'Hydrologie Appliquée, University of Abomey-Calavi, Institut National de l'eau, BP 526, Cotonou, Benin.,International Institute of Tropical Agriculture, 08 BP 0932, Cotonou, Benin
| | - Edia Flavien Dovonou
- Laboratoire d'Hydrologie Appliquée, University of Abomey-Calavi, Institut National de l'eau, BP 526, Cotonou, Benin
| | | | - Murielle Soglo
- International Institute of Tropical Agriculture, 08 BP 0932, Cotonou, Benin
| | - Razack Adéoti
- International Institute of Tropical Agriculture, 08 BP 0932, Cotonou, Benin
| | - Brice Gbaguidi
- International Institute of Tropical Agriculture, 08 BP 0932, Cotonou, Benin
| | - Seun Atoyebi
- International Institute of Tropical Agriculture, 08 BP 0932, Cotonou, Benin
| | - Fabrice Chandre
- UMR IRD 224-CNRS 5290-Université de Montpellier. MIVEGEC. Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, 911 Avenue Agropolis, BP 64501, 34394, Montpellier Cedex 5, France
| | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Benin
| | - Jo Lines
- London School of Hygiene and Tropical Medicine, London, UK
| | - Rousseau Djouaka
- International Institute of Tropical Agriculture, 08 BP 0932, Cotonou, Benin
| |
Collapse
|
25
|
Hemming-Schroeder E, Zhong D, Kibret S, Chie A, Lee MC, Zhou G, Atieli H, Githeko A, Kazura JW, Yan G. Microgeographic Epidemiology of Malaria Parasites in an Irrigated Area of Western Kenya by Deep Amplicon Sequencing. J Infect Dis 2020; 223:1456-1465. [PMID: 32803223 DOI: 10.1093/infdis/jiaa520] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 08/11/2020] [Indexed: 11/14/2022] Open
Abstract
To improve food security, investments in irrigated agriculture are anticipated to increase throughout Africa. However, the extent to which environmental changes from water resource development will impact malaria epidemiology remains unclear. This study was designed to compare the sensitivity of molecular markers used in deep amplicon sequencing for evaluating malaria transmission intensities and to assess malaria transmission intensity at various proximities to an irrigation scheme. Compared to ama1, csp, and msp1 amplicons, cpmp required the smallest sample size to detect differences in infection complexity between transmission risk zones. Transmission intensity was highest within 5 km of the irrigation scheme by polymerase chain reaction positivity rate, infection complexity, and linkage disequilibrium. The irrigated area provided a source of parasite infections for the surrounding 2- to 10-km area. This study highlights the suitability of the cpmp amplicon as a measure for transmission intensities and the impact of irrigation on microgeographic epidemiology of malaria parasites.
Collapse
Affiliation(s)
- Elizabeth Hemming-Schroeder
- Program in Public Health, University of California, Irvine, Irvine, California, USA.,Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, USA
| | - Daibin Zhong
- Program in Public Health, University of California, Irvine, Irvine, California, USA
| | - Solomon Kibret
- Program in Public Health, University of California, Irvine, Irvine, California, USA
| | - Amanda Chie
- Program in Public Health, University of California, Irvine, Irvine, California, USA
| | - Ming-Chieh Lee
- Program in Public Health, University of California, Irvine, Irvine, California, USA
| | - Guofa Zhou
- Program in Public Health, University of California, Irvine, Irvine, California, USA
| | - Harrysone Atieli
- School of Public Health and Community Development, Maseno University, Kisumu, Kenya
| | - Andrew Githeko
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - James W Kazura
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, USA
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, Irvine, California, USA
| |
Collapse
|