1
|
Katak RDM, Cintra AM, Burini BC, Marinotti O, Souza-Neto JA, Rocha EM. Biotechnological Potential of Microorganisms for Mosquito Population Control and Reduction in Vector Competence. INSECTS 2023; 14:718. [PMID: 37754686 PMCID: PMC10532289 DOI: 10.3390/insects14090718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/11/2023] [Accepted: 08/19/2023] [Indexed: 09/28/2023]
Abstract
Mosquitoes transmit pathogens that cause human diseases such as malaria, dengue fever, chikungunya, yellow fever, Zika fever, and filariasis. Biotechnological approaches using microorganisms have a significant potential to control mosquito populations and reduce their vector competence, making them alternatives to synthetic insecticides. Ongoing research has identified many microorganisms that can be used effectively to control mosquito populations and disease transmission. However, the successful implementation of these newly proposed approaches requires a thorough understanding of the multipronged microorganism-mosquito-pathogen-environment interactions. Although much has been achieved in discovering new entomopathogenic microorganisms, antipathogen compounds, and their mechanisms of action, only a few have been turned into viable products for mosquito control. There is a discrepancy between the number of microorganisms with the potential for the development of new insecticides and/or antipathogen products and the actual available products, highlighting the need for investments in the intersection of basic research and biotechnology.
Collapse
Affiliation(s)
- Ricardo de Melo Katak
- Malaria and Dengue Laboratory, Instituto Nacional de Pesquisas da Amazônia-INPA, Manaus 69060-001, AM, Brazil;
| | - Amanda Montezano Cintra
- Multiuser Central Laboratory, Department of Bioprocesses and Biotechnology, School of Agricultural Sciences, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (A.M.C.); (J.A.S.-N.)
| | - Bianca Correa Burini
- Florida Medical Entomology Laboratory, University of Florida, Vero Beach, FL 32962, USA;
| | - Osvaldo Marinotti
- Department of Biology, Indiana University, Bloomington, IN 47405, USA;
| | - Jayme A. Souza-Neto
- Multiuser Central Laboratory, Department of Bioprocesses and Biotechnology, School of Agricultural Sciences, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (A.M.C.); (J.A.S.-N.)
| | - Elerson Matos Rocha
- Multiuser Central Laboratory, Department of Bioprocesses and Biotechnology, School of Agricultural Sciences, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (A.M.C.); (J.A.S.-N.)
| |
Collapse
|
2
|
Ma X, Hu J, Ding C, Portieles R, Xu H, Gao J, Du L, Gao X, Yue Q, Zhao L, Borrás-Hidalgo O. New native Bacillus thuringiensis strains induce high insecticidal action against Culex pipiens pallens larvae and adults. BMC Microbiol 2023; 23:100. [PMID: 37055727 PMCID: PMC10099900 DOI: 10.1186/s12866-023-02842-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/28/2023] [Indexed: 04/15/2023] Open
Abstract
Mosquitoes of many species are key disease vectors, killing millions of people each year. Bacillus thuringiensis-based insecticide formulations are largely recognized as among the most effective, ecologically safe, and long-lasting methods of managing insect pests. New B. thuringiensis strains with high mosquito control effectiveness were isolated, identified, genetically defined, and physiologically characterized. Eight B. thuringiensis strains were identified and shown to carry endotoxin-producing genes. Using a scanning electron microscope, results revealed typical crystal forms of various shapes in B. thuringiensis strains. Fourteen cry and cyt genes were found in the strains examined. Although the genome of the B. thuringiensis A4 strain had twelve cry and cyt genes, not all of them were expressed, and only a few protein profiles were observed. The larvicidal activity of the eight B. thuringiensis strains was found to be positive (LC50: 1.4-28.5 g/ml and LC95: 15.3-130.3 g/ml). Bioassays in a laboratory environment demonstrated that preparations containing B. thuringiensis spores and crystals were particularly active to mosquito larvae and adults. These new findings show that the novel preparation containing B. thuringiensis A4 spores and crystals mixture might be used to control larval and adult mosquitoes in a sustainable and ecologically friendly manner.
Collapse
Affiliation(s)
- Xinmin Ma
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Jianjian Hu
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Chengsong Ding
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Roxana Portieles
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Hongli Xu
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Jingyao Gao
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Lihua Du
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Xiangyou Gao
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Qiulin Yue
- State Key Laboratory of Biobased Material and Green Papermaking, Shandong Provincial Key Lab of Microbial Engineering, Qilu University of Technology (Shandong Academic of Science), Jinan, People's Republic of China
| | - Lin Zhao
- State Key Laboratory of Biobased Material and Green Papermaking, Shandong Provincial Key Lab of Microbial Engineering, Qilu University of Technology (Shandong Academic of Science), Jinan, People's Republic of China
| | - Orlando Borrás-Hidalgo
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China.
- State Key Laboratory of Biobased Material and Green Papermaking, Shandong Provincial Key Lab of Microbial Engineering, Qilu University of Technology (Shandong Academic of Science), Jinan, People's Republic of China.
| |
Collapse
|
3
|
Campos M, Patel N, Marshall C, Gripkey H, Ditter RE, Crepeau MW, Toilibou A, Amina Y, Cornel AJ, Lee Y, Lanzaro GC. Population Genetics of Anopheles pretoriensis in Grande Comore Island. INSECTS 2022; 14:14. [PMID: 36661943 PMCID: PMC9866569 DOI: 10.3390/insects14010014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
Anopheles pretoriensis is widely distributed across Africa, including on oceanic islands such as Grande Comore in the Comoros. This species is known to be mostly zoophylic and therefore considered to have low impact on the transmission of human malaria. However, A. pretoriensis has been found infected with Plasmodium, suggesting that it may be epidemiologically important. In the present study, we sequenced and assembled the complete mitogenome of A. pretoriensis and inferred its phylogenetic relationship among other species in the subgenus Cellia. We also investigated the genetic structure of A. pretoriensis populations on Grande Comore Island, and between this island population and sites in continental Africa, using partial sequence of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Seven haplotypes were found on the island, one of which was ubiquitous. There was no clear divergence between island haplotypes and those found on the continent. The present work contributes knowledge on this understudied, yet abundant, Anopheles species.
Collapse
Affiliation(s)
- Melina Campos
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| | - Nikita Patel
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| | - Carly Marshall
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| | - Hans Gripkey
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| | - Robert E. Ditter
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| | - Marc W. Crepeau
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| | | | | | - Anthony J. Cornel
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
- Mosquito Control Research Laboratory, Kearney Research and Extension Center, Department of Entomology and Nematology, University of California, Parlier, CA 93648, USA
| | - Yoosook Lee
- Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
| | - Gregory C. Lanzaro
- Vector Genetics Laboratory, Department of Pathology, Microbiology, and Immunology, University of California, Davis, CA 95616, USA
| |
Collapse
|
4
|
Collins EL, Phelan JE, Hubner M, Spadar A, Campos M, Ward D, Acford-Palmer H, Gomes AR, Silva K, Ferrero Gomez L, Clark TG, Campino S. A next generation targeted amplicon sequencing method to screen for insecticide resistance mutations in Aedes aegypti populations reveals a rdl mutation in mosquitoes from Cabo Verde. PLoS Negl Trop Dis 2022; 16:e0010935. [PMID: 36512510 PMCID: PMC9746995 DOI: 10.1371/journal.pntd.0010935] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 11/06/2022] [Indexed: 12/15/2022] Open
Abstract
Aedes mosquito vectors transmit many viruses of global health concern, including dengue, chikungunya and Zika. These vector-borne viral diseases have a limited number of treatment options, and vaccines vary in their effectiveness. Consequently, integrated vector management is a primary strategy for disease control. However, the increasing emergence and spread of insecticide resistance is threatening the efficacy of vector control methods. Identifying mutations associated with resistance in vector populations is important to monitor the occurrence and evolution of insecticide resistance and inform control strategies. Rapid and cost-effective genome sequencing approaches are urgently needed. Here we present an adaptable targeted amplicon approach for cost-effective implementation within next generation sequencing platforms. This approach can identify single nucleotide polymorphisms (SNPs) and small insertions and deletions (indels) in genes involved in insecticide resistance in Aedes aegypti mosquitoes. We designed and tested eleven amplicons, which included segments of the ace-1 (carbamate target), the Voltage-Gated Sodium Channel (vgsc; pyrethroids, DDT and organochlorines), and rdl (dieldrin) genes; thereby covering established knockdown resistance (kdr) mutations (e.g., S989P, I1011M/V, V1016G/I and F1534C), with the potential to identify novel ones. The amplicon assays were designed with internal barcodes, to facilitate multiplexing of large numbers of mosquitoes at low cost, and were sequenced using an Illumina platform. Our approach was evaluated on 152 Ae. aegypti mosquitoes collected in Cabo Verde, an archipelago with a history of arbovirus outbreaks. The amplicon sequence data revealed 146 SNPs, including four non-synonymous polymorphisms in the vgsc gene, one in ace-1 and the 296S rdl mutation previously associated with resistance to organochlorines. The 296S rdl mutation was identified in 98% of mosquitoes screened, consistent with the past use of an organochlorine compound (e.g., DDT). Overall, our work shows that targeted amplicon sequencing is a rapid, robust, and cost-effective tool that can be used to perform high throughput monitoring of insecticide resistance.
Collapse
Affiliation(s)
- Emma L. Collins
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jody E. Phelan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Magdalena Hubner
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Anton Spadar
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Monica Campos
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Daniel Ward
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Holly Acford-Palmer
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Ana Rita Gomes
- Laboratory of Pathogen-Host Interactions (LPHI), CNRS, Montpellier University, Montpellier, France
| | - Keily Silva
- Universidade Jean Piaget (UniPiaget), Praia, Cabo Verde
| | | | - Taane G. Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| |
Collapse
|
5
|
Adhikari K, Khanikor B. Gradual reduction of susceptibility and enhanced detoxifying enzyme activities of laboratory-reared Aedes aegypti under exposure of temephos for 28 generations. Toxicol Rep 2021; 8:1883-1891. [PMID: 34900604 PMCID: PMC8639454 DOI: 10.1016/j.toxrep.2021.11.013] [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: 07/05/2021] [Revised: 11/01/2021] [Accepted: 11/23/2021] [Indexed: 01/14/2023] Open
Abstract
Aedes aegypti mosquitoes were exposed to temephos for 28 generations. This exposure led to a 7.83-fold decrease in temephos toxicity. With increase in generational time, Ae. aegypti exhibited increased detoxification. Increased detoxification correlated with increase in detoxifying enzymes. Repeated exposure of Ae. aegypti to temephos could lead to pesticide resistance.
Temephos, an organophosphate insecticide, is widely accepted for the control of Aedes aegypti, vector of infectious diseases such as dengue, chikungunya, yellow fever, and zika. However, there are claims that repeated and indiscriminate use of temephos has resulted in resistance development in exposed mosquito populations. The present study attempts to evaluate the continuous performance of temephos on the Ae. aegypti population, in laboratory conditions, in terms of toxicity and the effect on marker enzymes associated with metabolic resistance. Results of the toxicity bioassay showed that after the initial exposure, toxicity increased till F4 generation by 1.65 fold, and continuous exposure resulted in a 7.83 fold reduction in toxicity at F28 generation. Percent mortality result showed a marked reduction in mortality with the passage of generations while using the same series of concentrations, viz. 2 ppm, which was 100 % lethal at the initial nine generations, could kill only 22.66 % at F28. Resistance to organophosphates is mainly governed by metabolic detoxifying enzyme families of esterases, glutathione-s-transferase, and cytochrome P450. Analysis of these metabolic detoxifying enzymes showed an inverse trend to toxicity (i.e. toxicity increased in early generations as enzyme activity dropped and then dropped as enzyme activity increased). At the initial exposure, enzyme activity decreased in 2–4 generations, however, repeated exposure led to a significant increase in all the metabolic detoxifying enzymes. From the toxicity level as well as marker enzyme bioassay results, it can be inferred that mosquitoes showed increased detoxification in generational time with an increase in enzymes associated with metabolic detoxification. In conclusion, repeated application of temephos led to resistance development in Ae. aegypti which may be associated with the increase in metabolic detoxifying enzyme activities.
Collapse
Key Words
- ANOVA, analysis of variance
- BSA, bovine serum albumin
- CDNB, 1-chloro-2,4-dinitrobenzene
- CPCSEA, committee for the purpose of control and supervision of experiments on animals
- DEET, NN-diethyl-meta-toluamide
- DEM, diethyl maleate
- DMSO, dimethyl sulfoxide
- Dengue vector
- GSH, reduced glutathione
- GST, glutathione-s-transferase
- IAEC, institutional animal ethical committee
- LC50, lethal concentration 50
- Larvicide
- MAPK, mitogen-activated protein kinases
- NADPH, nicotinamide adenine dinucleotide phosphate hydrogen
- OD, optical density
- OP, organophosphate
- Organophosphates
- PBO, piperonyl butoxide
- PPM, parts per million
- Pesticide resistance
- SE, standard error
- SPSS, statistical package for the social sciences
- TMBZ, 3, 3, 5, 5-tetramethyl benzidine
- TPP, triphenyl phosphate
- Temephos
- WHO, World Health Organization
- ºC, degree celsius
Collapse
|
6
|
da Cruz DL, Paiva MHS, Guedes DRD, de Souza Gomes EC, Pires SG, Gomez LF, Ayres CFJ. First report of the L1014F kdr mutation in wild populations of Anopheles arabiensis in Cabo Verde, West Africa. Parasit Vectors 2021; 14:582. [PMID: 34802463 PMCID: PMC8607584 DOI: 10.1186/s13071-021-05088-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/08/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Due to the lack of vaccines, malaria control mainly involves the control of anopheline vectors (Anopheles spp.) using chemical insecticides. However, the prolonged and indiscriminate use of these compounds has led to the emergence of resistance in Anopheles populations in Africa. Insecticide resistance surveillance programs are less frequent in Cabo Verde than in other African countries. This study aimed to investigate the circulation of the L1014F and L1014S alleles in natural populations of Anopheles arabiensis collected from two sampling sites in the city of Praia, Cabo Verde. METHODS Anopheles larvae were collected from the two sampling sites and reared in the laboratory until the adult stage. Mosquitoes were first morphologically identified by classical taxonomy and then by molecular species identification using molecular markers. All Anopheles arabiensis were subjected to PCR analysis to screen for mutations associated to resistance in the Nav gene. RESULTS A total of 105 mosquitoes, all belonging to the Anopheles gambiae complex, were identified by classical taxonomy as well as by molecular taxonomy. Molecular identification showed that 100% of the An. gambiae senso lato specimens analyzed corresponded to An. arabiensis. Analysis of the Nav gene revealed the presence of L1014S and L1014F alleles with frequencies of 0.10 and 0.19, respectively. CONCLUSIONS Our data demonstrated, for the first time, the presence of the L1014F allele in the An. arabiensis population from Cabo Verde, as well as an increase in the frequency of the kdr L1014S allele reported in a previous study. The results of this study demonstrate the need to establish new approaches in vector control programs in Cabo Verde.
Collapse
Affiliation(s)
- Derciliano Lopes da Cruz
- Departamento de Entomologia, Instituto Aggeu Magalhães/Fundaçao Oswaldo Cruz (FIOCRUZ-PE), Av. Professor Moraes Rego s/n, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| | - Marcelo Henrique Santos Paiva
- Departamento de Entomologia, Instituto Aggeu Magalhães/Fundaçao Oswaldo Cruz (FIOCRUZ-PE), Av. Professor Moraes Rego s/n, Cidade Universitaria, Recife, PE, 50670-420, Brazil. .,Centro Academico do Agreste, Universidade Federal de Pernambuco, Rodovia BR-104, km 59-Nova Caruaru, Caruaru, PE, 55002-970, Brazil.
| | - Duschinka Ribeiro Duarte Guedes
- Departamento de Entomologia, Instituto Aggeu Magalhães/Fundaçao Oswaldo Cruz (FIOCRUZ-PE), Av. Professor Moraes Rego s/n, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| | - Elainne Christine de Souza Gomes
- Departamento de Parasitologia, Instituto Aggeu Magalhaes/Fundaçao Oswaldo Cruz (FIOCRUZ-PE), Av. Professor Moraes Rego s/n, Cidade Universitária, Recife, PE, 50670-420, Brazil
| | | | | | - Constância Flávia Junqueira Ayres
- Departamento de Entomologia, Instituto Aggeu Magalhães/Fundaçao Oswaldo Cruz (FIOCRUZ-PE), Av. Professor Moraes Rego s/n, Cidade Universitaria, Recife, PE, 50670-420, Brazil
| |
Collapse
|
7
|
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
|