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Omoke D, Impoinvil LM, Derilus D, Okeyo S, Saizonou H, Mulder N, Dada N, Lenhart A, Djogbénou L, Ochomo E. Whole transcriptomic analysis reveals overexpression of salivary gland and cuticular proteins genes in insecticide-resistant Anopheles arabiensis from Western Kenya. BMC Genomics 2024; 25:313. [PMID: 38532318 DOI: 10.1186/s12864-024-10182-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 03/04/2024] [Indexed: 03/28/2024] Open
Abstract
BACKGROUND Effective vector control is key to malaria prevention. However, this is now compromised by increased insecticide resistance due to continued reliance on insecticide-based control interventions. In Kenya, we have observed heterogenous resistance to pyrethroids and organophosphates in Anopheles arabiensis which is one of the most widespread malaria vectors in the country. We investigated the gene expression profiles of insecticide resistant An. arabiensis populations from Migori and Siaya counties in Western Kenya using RNA-Sequencing. Centers for Disease Control and Prevention (CDC) bottle assays were conducted using deltamethrin (DELTA), alphacypermethrin (ACYP) and pirimiphos-methyl (PMM) to determine the resistance status in both sites. RESULTS Mosquitoes from Migori had average mortalities of 91%, 92% and 58% while those from Siaya had 85%, 86%, and 30% when exposed to DELTA, ACYP and PMM, respectively. RNA-Seq analysis was done on pools of mosquitoes which survived exposure ('resistant'), mosquitoes that were not exposed, and the insecticide-susceptible An. arabiensis Dongola strain. Gene expression profiles of resistant mosquitoes from both Migori and Siaya showed an overexpression mainly of salivary gland proteins belonging to both the short and long form D7 genes, and cuticular proteins (including CPR9, CPR10, CPR15, CPR16). Additionally, the overexpression of detoxification genes including cytochrome P450s (CYP9M1, CYP325H1, CYP4C27, CYP9L1 and CYP307A1), 2 carboxylesterases and a glutathione-S-transferase (GSTE4) were also shared between DELTA, ACYP, and PMM survivors, pointing to potential contribution to cross resistance to both pyrethroid and organophosphate insecticides. CONCLUSION This study provides novel insights into the molecular basis of insecticide resistance in An. arabiensis in Western Kenya and suggests that salivary gland proteins and cuticular proteins are associated with resistance to multiple classes of insecticides.
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Affiliation(s)
- Diana Omoke
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research (CGHR), Kisumu, Kenya.
| | - Lucy Mackenzie Impoinvil
- Entomology Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA
| | - Dieunel Derilus
- Entomology Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA
| | - Stephen Okeyo
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research (CGHR), Kisumu, Kenya
| | | | | | - Nsa Dada
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Tropical Infectious Disease Research Center, University of Abomey- Calavi, Abomey Calavi, Benin
| | - Audrey Lenhart
- Entomology Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA
| | - Luc Djogbénou
- Entomology Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA
- Tropical Infectious Disease Research Center, University of Abomey- Calavi, Abomey Calavi, Benin
| | - Eric Ochomo
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research (CGHR), Kisumu, Kenya.
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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.
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Sympatric Populations of the Anopheles gambiae Complex in Southwest Burkina Faso Evolve Multiple Diverse Resistance Mechanisms in Response to Intense Selection Pressure with Pyrethroids. INSECTS 2022; 13:insects13030247. [PMID: 35323544 PMCID: PMC8955173 DOI: 10.3390/insects13030247] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/16/2022] [Accepted: 02/21/2022] [Indexed: 02/01/2023]
Abstract
Simple Summary Targeting mosquitoes with insecticides is one of the most effective methods to prevent malaria transmission. Although numbers of malaria cases have declined substantially this century, this pattern is not universal and Burkina Faso has one of the highest burdens of malaria; it is also a hotspot for the evolution of insecticide resistance in malaria vectors. We have established laboratory colonies from multiple species within the An. gambiae complex, the most efficient group of malaria vectors in the world, from larval collections in southwest Burkina Faso. Using bioassays with different insecticides widely used to control public health pests, we provide a profile of insecticide resistance in each of these colonies and, using molecular tools, reveal the genetic changes underpinning this resistance. We show that, whilst many resistance mechanisms are shared between species, there are some important differences which may affect resistance to current and future insecticide classes. The complexity, and diversity of resistance mechanisms highlights the importance of screening any potential new insecticide intended for use in malaria control against a wide range of populations. These stable laboratory colonies provide a valuable resource for insecticide discovery, and for further studies on the evolution and dispersal of insecticide resistance within and between species. Abstract Pyrethroid resistance in the Anopheles vectors of malaria is driving an urgent search for new insecticides that can be used in proven vector control tools such as insecticide treated nets (ITNs). Screening for potential new insecticides requires access to stable colonies of the predominant vector species that contain the major pyrethroid resistance mechanisms circulating in wild populations. Southwest Burkina Faso is an apparent hotspot for the emergence of pyrethroid resistance in species of the Anopheles gambiae complex. We established stable colonies from larval collections across this region and characterised the resistance phenotype and underpinning genetic mechanisms. Three additional colonies were successfully established (1 An. coluzzii, 1 An. gambiae and 1 An. arabiensis) to add to the 2 An. coluzzii colonies already established from this region; all 5 strains are highly resistant to pyrethroids. Synergism assays found that piperonyl butoxide (PBO) exposure was unable to fully restore susceptibility although exposure to a commercial ITN containing PBO resulted in 100% mortality. All colonies contained resistant alleles of the voltage gated sodium channel but with differing proportions of alternative resistant haplotypes. RNAseq data confirmed the role of P450s, with CYP6P3 and CYP6Z2 elevated in all 5 strains, and identified many other resistance mechanisms, some found across strains, others unique to a particular species. These strains represent an important resource for insecticide discovery and provide further insights into the complex genetic changes driving pyrethroid resistance.
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Messenger LA, Impoinvil LM, Derilus D, Yewhalaw D, Irish S, Lenhart A. A whole transcriptomic approach provides novel insights into the molecular basis of organophosphate and pyrethroid resistance in Anopheles arabiensis from Ethiopia. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2021; 139:103655. [PMID: 34562591 DOI: 10.1016/j.ibmb.2021.103655] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/15/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
The development of insecticide resistance in malaria vectors is of increasing concern in Ethiopia because of its potential implications for vector control failure. To better elucidate the specificity of resistance mechanisms and to facilitate the design of control strategies that minimize the likelihood of selecting for cross-resistance, a whole transcriptomic approach was used to explore gene expression patterns in a multi-insecticide resistant population of Anopheles arabiensis from Oromia Region, Ethiopia. This field population was resistant to the diagnostic doses of malathion (average mortality of 71.9%) and permethrin (77.4%), with pools of survivors and unexposed individuals analyzed using Illumina RNA-sequencing, alongside insecticide susceptible reference strains. This population also demonstrated deltamethrin resistance but complete susceptibility to alpha-cypermethrin, bendiocarb and propoxur, providing a phenotypic basis for detecting insecticide-specific resistance mechanisms. Transcriptomic data revealed overexpression of genes including cytochrome P450s, glutathione-s-transferases and carboxylesterases (including CYP4C36, CYP6AA1, CYP6M2, CYP6M3, CYP6P4, CYP9K1, CYP9L1, GSTD3, GSTE2, GSTE3, GSTE4, GSTE5, GSTE7 and two carboxylesterases) that were shared between malathion and permethrin survivors. We also identified nineteen highly overexpressed cuticular-associated proteins (including CYP4G16, CYP4G17 and chitinase) and eighteen salivary gland proteins (including D7r4 short form salivary protein), which may be contributing to a non-specific resistance phenotype by either enhancing the cuticular barrier or promoting binding and sequestration of insecticides, respectively. These findings provide novel insights into the molecular basis of insecticide resistance in this lesser well-characterized major malaria vector species.
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Affiliation(s)
- Louisa A Messenger
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, U.S. Centers for Disease Control and Prevention, 1600 Clifton Rd. Atlanta, GA, 30329, USA; American Society for Microbiology, 1752 N Street, NW Washington, DC, 20036, USA; Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Lucy Mackenzie Impoinvil
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, U.S. Centers for Disease Control and Prevention, 1600 Clifton Rd. Atlanta, GA, 30329, USA
| | - Dieunel Derilus
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, U.S. Centers for Disease Control and Prevention, 1600 Clifton Rd. Atlanta, GA, 30329, USA
| | - Delenasaw Yewhalaw
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia; Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia
| | - Seth Irish
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, U.S. Centers for Disease Control and Prevention, 1600 Clifton Rd. Atlanta, GA, 30329, USA; President's Malaria Initiative, Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, U.S. Centers for Disease Control and Prevention, 1600 Clifton Rd. Atlanta, GA, 30329, USA
| | - Audrey Lenhart
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, U.S. Centers for Disease Control and Prevention, 1600 Clifton Rd. Atlanta, GA, 30329, USA.
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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.
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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
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Namias A, Jobe NB, Paaijmans KP, Huijben S. The need for practical insecticide-resistance guidelines to effectively inform mosquito-borne disease control programs. eLife 2021; 10:e65655. [PMID: 34355693 PMCID: PMC8346280 DOI: 10.7554/elife.65655] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 07/26/2021] [Indexed: 11/13/2022] Open
Abstract
Monitoring local mosquito populations for insecticide resistance is critical for effective vector-borne disease control. However, widely used phenotypic assays, which are designed to monitor the emergence and spread of insecticide resistance (technical resistance), do not translate well to the efficacy of vector control products to suppress mosquito numbers in the field (practical resistance). This is because standard testing conditions such as environmental conditions, exposure dose, and type of substrate differ dramatically from those experienced by mosquitoes under field conditions. In addition, field mosquitoes have considerably different physiological characteristics such as age and blood-feeding status. Beyond this, indirect impacts of insecticide resistance and/or exposure on mosquito longevity, pathogen development, host-seeking behavior, and blood-feeding success impact disease transmission. Given the limited number of active ingredients currently available and the observed discordance between resistance and disease transmission, we conclude that additional testing guidelines are needed to determine practical resistance-the efficacy of vector control tools under relevant local conditions- in order to obtain programmatic impact.
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Affiliation(s)
- Alice Namias
- Département de Biologie, Ecole Normale Supérieure, PSL Research University, Paris, France
- Institut des Sciences de l'Evolution de Montpellier (ISEM), Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France
| | - Ndey Bassin Jobe
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Life Sciences C, Tempe, United States
| | - Krijn Petrus Paaijmans
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Life Sciences C, Tempe, United States
- The Biodesign Center for Immunotherapy, Vaccines and Virotherapy, Arizona State University, Biodesign Institute, Tempe, United States
- ISGlobal, Carrer del Rosselló, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Distrito da Manhiça, Mozambique
| | - Silvie Huijben
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Life Sciences C, Tempe, United States
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Gao Y, Kim JH, Jeong IH, Clark JM, Lee SH. Transcriptomic identification and characterization of genes commonly responding to sublethal concentrations of six different insecticides in the common fruit fly, Drosophila melanogaster. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2021; 175:104852. [PMID: 33993970 DOI: 10.1016/j.pestbp.2021.104852] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/25/2021] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
Pretreatment with sublethal concentrations (LC10) of six insecticides (chlorantraniliprole, cypermethrin, dinotefuran, indoxacarb, ivermectin, and spinosad) significantly elevated tolerance of the common fruit fly Drosophila melanogaster to lethal concentration of the respective insecticide. Commonly responding genes to sublethal treatments of the six insecticides were identified by transcriptome analysis based on a fold change >1.5 or < -1.5, and p < 0.05 as selection criteria. Following treatment with all the six insecticides, 26 transcripts were commonly over-transcribed, whereas 30 transcripts were commonly under-transcribed. Reliability of the transcriptome data was confirmed by quantitative PCR. A majority of the over-transcribed genes included those related to olfactory behavior, such as odorant-binding proteins, as well as immune-related genes, including attacin, diptericin, and immune-induced molecule 18. In contrast, genes belonging to the mitochondrial respiratory chain, such as mitochondrial NADH-ubiquinone oxidoreductase chain 1/3/4/5 and mitochondrial cytochrome b/c, were commonly under-transcribed. Furthermore, genes related to eggshell formation and motion were also under-transcribed, which may indicate a possible energy trade-off for xenobiotic stress. In summary, most of the differentially expressed genes were not directly related to well-known detoxification genes, suggesting that the roles of commonly expressed tolerance-related genes are not likely related to direct metabolic detoxification, but rather are associated with restoration of homeostasis.
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Affiliation(s)
- Yue Gao
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Ju Hyeon Kim
- Research Institute for Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - In Hong Jeong
- Division of Crop Protection, National Institute of Agricultural Science, Rural Development Administration, Republic of Korea
| | - J Marshall Clark
- Department of Veterinary & Animal Sciences, University of Massachusetts at Amherst, MA, USA
| | - Si Hyeock Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea; Research Institute for Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea.
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Korti MY, Ageep TB, Adam AI, Shitta KB, Hassan AA, Algadam AA, Baleela RM, Saad HA, Abuelmaali SA. Status of insecticide susceptibility in Anopheles arabiensis and detection of the knockdown resistance mutation (kdr) concerning agricultural practices from Northern Sudan state, Sudan. J Genet Eng Biotechnol 2021; 19:49. [PMID: 33779858 PMCID: PMC8006520 DOI: 10.1186/s43141-021-00142-1] [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: 07/05/2020] [Accepted: 03/11/2021] [Indexed: 11/10/2022]
Abstract
BACKGROUND Chemical control has been the most efficient method in mosquito control, the development of insecticide resistance in target populations has a significant impact on vector control. The use of agricultural pesticides may have a profound impact on the development of resistance in the field populations of malaria vectors. Our study focused on insecticide resistance and knockdown resistance (kdr) of Anopheles arabiensis populations from Northern Sudan, related to agricultural pesticide usage. RESULTS Anopheles arabiensis from urban and rural localities (Merowe and Al-hamadab) were fully susceptible to bendiocarb 0.1% and permethrin 0.75% insecticides while resistant to DDT 4% and malathion 5%. The population of laboratory reference colony F189 from Dongola showed a mortality of 91% to DDT (4%) and fully susceptible to others. GLM analysis indicated that insecticides, sites, site type, and their interaction were determinant factors on mortality rates (P < 0.01). Except for malathion, mortality rates of all insecticides were not significant (P > 0.05) according to sites. Mortality rates of malathion and DDT were varied significantly (P < 0.0001 and P < 0.05 respectively) by site types, while mortality rates of bendiocarb and permethrin were not significant (P >0.05). The West African kdr mutation (L1014F) was found in urban and rural sites. Even though, the low-moderate frequency of kdr (L1014F) mutation was observed. The findings presented here for An. arabiensis showed no correlation between the resistant phenotype as ascertained by bioassay and the presence of the kdr mutation, with all individuals tested except the Merowe site which showed a moderate association with DDT (OR= 6 in allelic test), suggesting that kdr genotype would be a poor indicator of phenotypic resistance. CONCLUSION The results provide critical pieces of information regarding the insecticide susceptibility status of An. arabiensis in northern Sudan. The usage of the same pesticides in agricultural areas seemed to affect the Anopheles susceptibility when they are exposed to those insecticides in the field. The kdr mutation might have a less role than normally expected in pyrethroids resistance; however, other resistance genes should be in focus. These pieces of information will help to improve the surveillance system and The implication of different vector control programs employing any of these insecticides either in the treatment of bed nets or for indoor residual spraying would achieve satisfactory success rates.
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Affiliation(s)
- M Y Korti
- Tropical Medicine Research Institute, National Center for Research, Khartoum, Sudan
| | - T B Ageep
- Tropical Medicine Research Institute, National Center for Research, Khartoum, Sudan
| | - A I Adam
- Tropical Medicine Research Institute, National Center for Research, Khartoum, Sudan
| | - K B Shitta
- Department of Biological Sciences, Federal University Lokoja, Lokoja, Kogi State, Nigeria
| | - A A Hassan
- Tropical Medicine Research Institute, National Center for Research, Khartoum, Sudan
| | - A A Algadam
- Tropical Medicine Research Institute, National Center for Research, Khartoum, Sudan
| | - R M Baleela
- Department of Zoology, Faculty of Sciences, University of Khartoum, Khartoum, Sudan
| | - H A Saad
- Department of Zoology, Faculty of Sciences, University of Khartoum, Khartoum, Sudan
| | - S A Abuelmaali
- Department of Medical Entomology, National Public Health Laboratory, Federal Ministry of Health, Khartoum, Sudan.
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Black WC, Snell TK, Saavedra-Rodriguez K, Kading RC, Campbell CL. From Global to Local-New Insights into Features of Pyrethroid Detoxification in Vector Mosquitoes. INSECTS 2021; 12:insects12040276. [PMID: 33804964 PMCID: PMC8063960 DOI: 10.3390/insects12040276] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/18/2021] [Accepted: 03/20/2021] [Indexed: 02/04/2023]
Abstract
The threat of mosquito-borne diseases continues to be a problem for public health in subtropical and tropical regions of the world; in response, there has been increased use of adulticidal insecticides, such as pyrethroids, in human habitation areas over the last thirty years. As a result, the prevalence of pyrethroid-resistant genetic markers in natural mosquito populations has increased at an alarming rate. This review details recent advances in the understanding of specific mechanisms associated with pyrethroid resistance, with emphasis on features of insecticide detoxification and the interdependence of multiple cellular pathways. Together, these advances add important context to the understanding of the processes that are selected in resistant mosquitoes. Specifically, before pyrethroids bind to their targets on motoneurons, they must first permeate the outer cuticle and diffuse to inner tissues. Resistant mosquitoes have evolved detoxification mechanisms that rely on cytochrome P450s (CYP), esterases, carboxyesterases, and other oxidation/reduction (redox) components to effectively detoxify pyrethroids to nontoxic breakdown products that are then excreted. Enhanced resistance mechanisms have evolved to include alteration of gene copy number, transcriptional and post-transcriptional regulation of gene expression, as well as changes to cellular signaling mechanisms. Here, we outline the variety of ways in which detoxification has been selected in various mosquito populations, as well as key gene categories involved. Pathways associated with potential new genes of interest are proposed. Consideration of multiple cellular pathways could provide opportunities for development of new insecticides.
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Assessing cross-resistance within the pyrethroids in terms of their interactions with key cytochrome P450 enzymes and resistance in vector populations. Parasit Vectors 2021; 14:115. [PMID: 33602297 PMCID: PMC7893915 DOI: 10.1186/s13071-021-04609-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 01/23/2021] [Indexed: 01/21/2023] Open
Abstract
Background It is important to understand whether the potential impact of pyrethroid resistance on malaria control can be mitigated by switching between different pyrethroids or whether cross-resistance within this insecticide class precludes this approach. Methods Here we assess the relationships among pyrethroids in terms of their binding affinity to, and depletion by, key cytochrome P450 enzymes (hereafter P450s) that are known to confer metabolic pyrethroid resistance in Anopheles gambiae (s.l.) and An. funestus, in order to identify which pyrethroids may diverge from the others in their vulnerability to resistance. We then investigate whether these same pyrethroids also diverge from the others in terms of resistance in vector populations. Results We found that the type I and II pyrethroids permethrin and deltamethrin, respectively, are closely related in terms of binding affinity to key P450s, depletion by P450s and resistance within vector populations. Bifenthrin, which lacks the common structural moiety of most pyrethroids, diverged from the other pyrethroids tested in terms of both binding affinity to key P450s and depletion by P450s, but resistance to bifenthrin has rarely been tested in vector populations and was not analysed here. Etofenprox, which also lacks the common structural moiety of most pyrethroids, diverged from the more commonly deployed pyrethroids in terms of binding affinity to key P450s and resistance in vector populations, but did not diverge from these pyrethroids in terms of depletion by the P450s. The analysis of depletion by the P450s indicated that etofenprox may be more vulnerable to metabolic resistance mechanisms in vector populations. In addition, greater resistance to etofenprox was found across Aedes aegypti populations, but greater resistance to this compound was not found in any of the malaria vector species analysed. The results for pyrethroid depletion by anopheline P450s in the laboratory were largely not repeated in the findings for resistance in malaria vector populations. Conclusion Importantly, the prevalence of resistance to the pyrethroids α-cypermethrin, cyfluthrin, deltamethrin, λ-cyhalothrin and permethrin was correlated across malaria vector populations, and switching between these compounds as a tool to mitigate against pyrethroid resistance is not advised without strong evidence supporting a true difference in resistance.![]()
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Vontas J, Katsavou E, Mavridis K. Cytochrome P450-based metabolic insecticide resistance in Anopheles and Aedes mosquito vectors: Muddying the waters. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2020; 170:104666. [PMID: 32980073 DOI: 10.1016/j.pestbp.2020.104666] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 07/13/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
Despite the substantial progress achieved in the characterization of cytochrome P450 (CYP) -based resistance mechanisms in mosquitoes, a number of questions remain unanswered. These include: (i) the regulation and physiology of resistance conferring CYPs; (ii) the actual contribution of CYPs in resistance alone or in combination with other detoxification partners or other resistance mechanisms; (iii) the association between overexpression levels and allelic variation, with the catalytic activity and the intensity of resistance and (iv) the true value of molecular diagnostics targeting CYP markers, for driving decision making in the frame of Insecticide Resistance Management applications. Furthermore, the translation of CYP - based insecticide resistance research in mosquitoes into practical applications, is being developed, but it is not fully exploited, as yet. Examples include the production of high throughput platforms for screening the liability (stability) or inhibition potential of novel insecticidal leads and synergists (add-ons), as well as the exploration of the negative cross resistance concept (i.e. detoxification of certain insecticides, but activation of others pro-insecticides). The goal of this review is to critically summarise the current knowledge and the gaps of the CYP-based metabolic insecticide resistance in Anopheles and Aedes mosquito vectors. The progress and limitations of the protein and the reverse/forward genetic approaches, the understanding and importance of molecular and physiological aspects, as well as the current and future exploitation routes of CYP research are discussed.
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Affiliation(s)
- John Vontas
- Foundation for Research and Technology (FORTH), Institute of Molecular Biology and Biotechnology (IMBB), Nikolaou Plastira Street 100, 70013, Heraklion, Crete, Greece; Department of Crop Science, Agricultural University of Athens, Iera Odos 875, 11855, Athens, Greece.
| | - Eva Katsavou
- Department of Crop Science, Agricultural University of Athens, Iera Odos 875, 11855, Athens, Greece
| | - Konstantinos Mavridis
- Foundation for Research and Technology (FORTH), Institute of Molecular Biology and Biotechnology (IMBB), Nikolaou Plastira Street 100, 70013, Heraklion, Crete, Greece
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Hancock PA, Hendriks CJM, Tangena JA, Gibson H, Hemingway J, Coleman M, Gething PW, Cameron E, Bhatt S, Moyes CL. Mapping trends in insecticide resistance phenotypes in African malaria vectors. PLoS Biol 2020; 18:e3000633. [PMID: 32584814 PMCID: PMC7316233 DOI: 10.1371/journal.pbio.3000633] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 05/11/2020] [Indexed: 11/25/2022] Open
Abstract
Mitigating the threat of insecticide resistance in African malaria vector populations requires comprehensive information about where resistance occurs, to what degree, and how this has changed over time. Estimating these trends is complicated by the sparse, heterogeneous distribution of observations of resistance phenotypes in field populations. We use 6,423 observations of the prevalence of resistance to the most important vector control insecticides to inform a Bayesian geostatistical ensemble modelling approach, generating fine-scale predictive maps of resistance phenotypes in mosquitoes from the Anopheles gambiae complex across Africa. Our models are informed by a suite of 111 predictor variables describing potential drivers of selection for resistance. Our maps show alarming increases in the prevalence of resistance to pyrethroids and DDT across sub-Saharan Africa from 2005 to 2017, with mean mortality following insecticide exposure declining from almost 100% to less than 30% in some areas, as well as substantial spatial variation in resistance trends.
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Affiliation(s)
| | | | - Julie-Anne Tangena
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Harry Gibson
- Big Data Institute, University of Oxford, Oxford, United Kingdom
| | - Janet Hemingway
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Michael Coleman
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Peter W. Gething
- Telethon Kids Institute, Perth Children's Hospital, Perth, Australia
- Curtin University, Bentley, Perth, Australia
| | - Ewan Cameron
- Big Data Institute, University of Oxford, Oxford, United Kingdom
| | - Samir Bhatt
- Department of Infectious Disease Epidemiology, Imperial College, St Mary’s Hospital, London, United Kingdom
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Venugopala KN, Ramachandra P, Tratrat C, Gleiser RM, Bhandary S, Chopra D, Morsy MA, Aldhubiab BE, Attimarad M, Nair AB, Sreeharsha N, Venugopala R, Deb PK, Chandrashekharappa S, Khalil HE, Alwassil OI, Abed SN, Bataineh YA, Palenge R, Haroun M, Pottathil S, Girish MB, Akrawi SH, Mohanlall V. Larvicidal Activities of 2-Aryl-2,3-Dihydroquinazolin -4-ones against Malaria Vector Anopheles arabiensis, In Silico ADMET Prediction and Molecular Target Investigation. Molecules 2020; 25:molecules25061316. [PMID: 32183140 PMCID: PMC7144721 DOI: 10.3390/molecules25061316] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/14/2022] Open
Abstract
Malaria, affecting all continents, remains one of the life-threatening diseases introduced by parasites that are transmitted to humans through the bites of infected Anopheles mosquitoes. Although insecticides are currently used to reduce malaria transmission, their safety concern for living systems, as well as the environment, is a growing problem. Therefore, the discovery of novel, less toxic, and environmentally safe molecules to effectively combat the control of these vectors is in high demand. In order to identify new potential larvicidal agents, a series of 2-aryl-1,2-dihydroquinazolin-4-one derivatives were synthesized and evaluated for their larvicidal activity against Anopheles arabiensis. The in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of the compounds were also investigated and most of the derivatives possessed a favorable ADMET profile. Computational modeling studies of the title compounds demonstrated a favorable binding interaction against the acetylcholinesterase enzyme molecular target. Thus, 2-aryl-1,2-dihydroquinazolin-4-ones were identified as a novel class of Anopheles arabiensis insecticides which can be used as lead molecules for the further development of more potent and safer larvicidal agents for treating malaria.
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Affiliation(s)
- Katharigatta N. Venugopala
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
- Department of Biotechnology and Food Technology, Durban University of Technology, Durban 4001, South Africa;
- Correspondence:
| | - Pushpalatha Ramachandra
- Department of Chemistry, School of Applied Sciences, REVA University, Bangalore 560 064, India; (P.R.); (R.P.)
| | - Christophe Tratrat
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Raquel M. Gleiser
- CREAN-IMBIV (UNC-CONICET), Av. Valparaíso s.n., Córdoba, Argentina and FCEFyN, AV. Sarsfield 299, Universidad Nacional de Cordoba, Cordoba 5000, Argentina;
| | - Subhrajyoti Bhandary
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India; (S.B.); (D.C.)
| | - Deepak Chopra
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India; (S.B.); (D.C.)
| | - Mohamed A. Morsy
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
- Department of Pharmacology, Faculty of Medicine, Minia University, El-Minia 61511, Egypt
| | - Bandar E. Aldhubiab
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Mahesh Attimarad
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Anroop B. Nair
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Nagaraja Sreeharsha
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Rashmi Venugopala
- Department of Public Health Medicine, University of KwaZulu-Natal, Howard College Campus, Durban 4001, South Africa;
| | - Pran Kishore Deb
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, P.O. Box 1, Amman 19392, Jordan; (P.K.D.); (S.N.A.); (Y.A.B.)
| | - Sandeep Chandrashekharappa
- Institute for Stem Cell Biology and Regenerative Medicine, NCBS, TIFR, GKVK, Bellary Road, Bangalore 560 065, India;
| | - Hany Ezzat Khalil
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
- Department of Pharmacognosy, Faculty of Pharmacy, Minia University, Minia 61519, Egypt
| | - Osama I. Alwassil
- Department of Pharmaceutical Sciences, College of Pharmacy, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia;
| | - Sara Nidal Abed
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, P.O. Box 1, Amman 19392, Jordan; (P.K.D.); (S.N.A.); (Y.A.B.)
| | - Yazan A. Bataineh
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, P.O. Box 1, Amman 19392, Jordan; (P.K.D.); (S.N.A.); (Y.A.B.)
| | - Ramachandra Palenge
- Department of Chemistry, School of Applied Sciences, REVA University, Bangalore 560 064, India; (P.R.); (R.P.)
| | - Michelyne Haroun
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Shinu Pottathil
- Department of Biomedical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Meravanige B. Girish
- Department of Biomedical Sciences, College of Medicine, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Sabah H. Akrawi
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Viresh Mohanlall
- Department of Biotechnology and Food Technology, Durban University of Technology, Durban 4001, South Africa;
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Stica C, Jeffries CL, Irish SR, Barry Y, Camara D, Yansane I, Kristan M, Walker T, Messenger LA. Characterizing the molecular and metabolic mechanisms of insecticide resistance in Anopheles gambiae in Faranah, Guinea. Malar J 2019; 18:244. [PMID: 31315630 PMCID: PMC6637595 DOI: 10.1186/s12936-019-2875-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 07/08/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND In recent years, the scale-up of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) has greatly reduced malaria transmission. However, malaria remains a global public health concern with the majority of the disease burden in sub-Saharan Africa. Insecticide resistance is a growing problem among Anopheles vector populations, with potential implications for the continued effectiveness of available control interventions. Improved understanding of current resistance levels and underlying mechanisms is essential to design appropriate management strategies and to mitigate future selection for resistance. METHODS Anopheles gambiae sensu lato mosquitoes were collected from three villages in Faranah Prefecture, Guinea and their levels of susceptibility to seven insecticides were measured using CDC resistance intensity bioassays. Synergist assays with piperonyl butoxide (PBO) were also undertaken to assess the role of elevated mixed-function oxidases in resistance. Five hundred and sixty-three mosquitoes underwent molecular characterization of vector species, presence of target site mutations (L1014F kdr, N1575Y and G119S Ace-1), Plasmodium falciparum infection, and relative expression of three metabolic genes (CYP6M2, CYP6P3 and GSTD3). RESULTS In Faranah, resistance to permethrin and deltamethrin was observed, as well as possible resistance to bendiocarb. All assayed vector populations were fully susceptible to alpha-cypermethrin, pirimiphos-methyl, clothianidin and chlorfenapyr. Plasmodium falciparum infection was detected in 7.3% (37/508) of mosquitoes tested. The L1014F kdr mutation was found in 100% of a sub-sample of 60 mosquitoes, supporting its fixation in the region. The N1575Y mutation was identified in 20% (113/561) of individuals, with ongoing selection evidenced by significant deviations from Hardy-Weinberg equilibrium. The G119S Ace-1 mutation was detected in 62.1% (18/29) of mosquitoes tested and was highly predictive of bendiocarb bioassay survival. The metabolic resistance genes, CYP6M2, CYP6P3 and GSTD3, were found to be overexpressed in wild resistant and susceptible An. gambiae sensu stricto populations, compared to a susceptible G3 colony. Furthermore, CYP6P3 was significantly overexpressed in bendiocarb survivors, implicating its potential role in carbamate resistance in Faranah. CONCLUSIONS Identification of intense resistance to permethrin and deltamethrin in Faranah, is of concern, as the Guinea National Malaria Control Programme (NMCP) relies exclusively on the distribution of pyrethroid-treated LLINs for vector control. Study findings will be used to guide current and future control strategies in the region.
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Affiliation(s)
- Caleb Stica
- Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Claire L Jeffries
- Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Seth R Irish
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
- Division of Parasitic Diseases and Malaria, President's Malaria Initiative, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Yaya Barry
- Programme National de Lutte Contre le Paludisme, Ministère de la Santé, BP. 595, Conakry, Guinea
| | - Denka Camara
- Programme National de Lutte Contre le Paludisme, Ministère de la Santé, BP. 595, Conakry, Guinea
| | | | - Mojca Kristan
- Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Thomas Walker
- Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Louisa A Messenger
- Department of Disease Control, Faculty of Infectious Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
- Entomology Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA.
- American Society for Microbiology, 1752 N Street NW, Washington, DC, 20036, USA.
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Quality of fixed dose artemether/lumefantrine products in Jimma Zone, Ethiopia. Malar J 2019; 18:236. [PMID: 31307475 PMCID: PMC6628471 DOI: 10.1186/s12936-019-2872-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/06/2019] [Indexed: 11/26/2022] Open
Abstract
Background Malaria caused by Plasmodium vivax and Plasmodium falciparum is among the major public health problems in most endemic areas of the world. Artemisinin-based combination therapy (ACT) has been recommended as a first-line treatment for uncomplicated Plasmodium falciparum malaria almost in all endemic regions. Since ineffectively regulated medicines in resource limited settings could favour infiltration of poor quality anti-malarial medicines into pharmaceutical supply chain and jeopardize a positive treatment outcome, regular monitoring of the quality of anti-malarial medicines is critical. Thus, the aim of this study was to assess the quality of fixed dose combination (FDC) artemether (ART)/lumefantrine (LUM) tablets available in Jimma zone, Ethiopia. Methods This study was conducted in Jimma zone, Ethiopia. A total of 74 samples of FDC ART/LUM (20 mg ART/120 mg LUM) tablets were collected from 27 public facilities. All samples were subjected to visual inspection and the relevant information was recorded. The samples were transported to Jimma University Laboratory of Drug Quality (JuLaDQ) and stored at ambient temperature (20 °C to 25 °C) until analysis. The Pharmacopoeial conform/non-conform methods and the risk-based Derringer’s desirability function approach were employed to assess the pharmaceutical quality of the investigated products. Results The visual inspection results revealed that there were no signs of falsified in the investigated products. Identification test results of samples indicated that all samples contained the stated active pharmaceutical ingredients (APIs). The results of uniformity of mass indicated that all samples complied with International Pharmacopoeial specification limits. The assay results, expressed as percent label claim (%lc) of ART (89.8 to 108.8%, mean ± SD = 99.1 ± 3.9%) and LUM (90.0 to 111.9%, mean ± SD = 98.2 ± 3.8%) revealed that, all samples complied with International Pharmacopoeia acceptance specification limits (i.e. 90–110%lc), except one generic product (IPCA Laboratories Ltd., India) which contains excessive LUM (111.9 ± 1.7%lc). The risk priority number (RPN) results revealed that assay (RPN = 392) is relatively the most critical quality attribute followed by identity (RPN = 280) and mass uniformity (40). Quality evaluation based on psycho-physical Harrington’s scale revealed that more than 96% of samples were within the acceptable ranges (D ≥ 0.7–1.0). Conclusions Both Pharmacopoeial and risk-based desirability function approaches to quality evaluation applied to the investigated products revealed that above 96% FDC ART/LUM tablets circulating in public settings of Jimma zone are of good quality. Electronic supplementary material The online version of this article (10.1186/s12936-019-2872-1) contains supplementary material, which is available to authorized users.
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Simma EA, Dermauw W, Balabanidou V, Snoeck S, Bryon A, Clark RM, Yewhalaw D, Vontas J, Duchateau L, Van Leeuwen T. Genome-wide gene expression profiling reveals that cuticle alterations and P450 detoxification are associated with deltamethrin and DDT resistance in Anopheles arabiensis populations from Ethiopia. PEST MANAGEMENT SCIENCE 2019; 75:1808-1818. [PMID: 30740870 DOI: 10.1002/ps.5374] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/18/2019] [Accepted: 02/04/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Vector control is the main intervention in malaria control and elimination strategies. However, the development of insecticide resistance is one of the major challenges for controlling malaria vectors. Anopheles arabiensis populations in Ethiopia showed resistance against both DDT and the pyrethroid deltamethrin. Although an L1014F target-site resistance mutation was present in the voltage gated sodium channel of investigated populations, the levels of resistance indicated the presence of additional resistance mechanisms. In this study, we used genome-wide transcriptome profiling by RNAseq to assess differentially expressed genes between three deltamethrin and DDT resistant An. arabiensis field populations - Asendabo, Chewaka and Tolay - and two susceptible strains - Sekoru and Mozambique. RESULTS Both RNAseq analysis and RT-qPCR showed that a glutathione-S-transferase, gstd3, and a cytochrome P450 monooxygenase, cyp6p4, were significantly overexpressed in the group of resistant populations compared to the susceptible strains, suggesting that the enzymes they encode play a key role in metabolic resistance against deltamethrin or DDT. Furthermore, a gene ontology enrichment analysis showed that expression changes of cuticle related genes were strongly associated with insecticide resistance. Although this did not translate in increased thickness of the procuticle, a higher cuticular hydrocarbon content was observed in a resistant population. CONCLUSION Our transcriptome sequencing of deltamethrin and DDT resistant An. arabiensis populations from Ethiopia suggests non-target site resistance mechanisms and paves the way for further investigation of the role of cuticle composition in insecticide resistance of malaria vectors. © 2019 Society of Chemical Industry.
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Affiliation(s)
- Eba A Simma
- Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Wannes Dermauw
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Vasileia Balabanidou
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department of Biology, University of Crete, Heraklion, Greece
| | - Simon Snoeck
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Astrid Bryon
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Richard M Clark
- School of Biological Sciences, University of Utah, Salt Lake City, UT, USA
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT, USA
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, College of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department of Crop Science, Pesticide Science Lab, Agricultural University of Athens, Athens, Greece
| | - Luc Duchateau
- Department of Nutrition, Genetics and Ethology, Ghent University, Merelbeke, Belgium
| | - Thomas Van Leeuwen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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Elanga-Ndille E, Nouage L, Binyang A, Assatse T, Tene-Fossog B, Tchouakui M, Nguete Nguiffo D, Irving H, Ndo C, Awono-Ambene P, Wondji CS. Overexpression of Two Members of D7 Salivary Genes Family is Associated with Pyrethroid Resistance in the Malaria Vector Anopheles Funestus s.s. but Not in Anopheles Gambiae in Cameroon. Genes (Basel) 2019; 10:genes10030211. [PMID: 30871094 PMCID: PMC6472155 DOI: 10.3390/genes10030211] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/28/2019] [Accepted: 03/07/2019] [Indexed: 01/10/2023] Open
Abstract
D7 family proteins are among the most expressed salivary proteins in mosquitoes. They facilitate blood meal intake of the mosquito by scavenging host amines that induce vasoconstriction, platelet aggregation and pain. Despite this important role, little information is available on the impact of insecticide resistance on the regulation of D7 proteins and consequently on the blood feeding success. In this study, real-time quantitative polymerase chain reaction (qPCR) analyses were performed to investigate how pyrethroid resistance could influence the expression of genes encoding D7 family proteins in Anopheles gambiae and Anopheles funestus s.s. mosquitoes from Elon in the Central Cameroon. Out of 328 collected mosquitoes, 256 were identified as An. funestus sl and 64 as An. gambiae sl. Within the An. funestus group, An. funestus s.s. was the most abundant species (95.95%) with An. rivulorum, An. parensis and An. rivulorum-like also detected. All An. gambiae s.l mosquitoes were identified as An. gambiae. High levels of pyrethroid resistance were observed in both An. gambiae and An. funestus mosquitoes. RT-qPCR analyses revealed a significant overexpression of two genes encoding D7 proteins, D7r3 and D7r4, in pyrethroids resistant An. funestus. However, no association was observed between the polymorphism of these genes and their overexpression. In contrast, overall D7 salivary genes were under-expressed in pyrethroid resistant An. gambiae. This study provides preliminary evidences that pyrethroid resistance could influence blood meal intake through over-expression of D7 proteins although future studies will help establishing potential impact on vectorial capacity.
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Affiliation(s)
- Emmanuel Elanga-Ndille
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
| | - Lynda Nouage
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon.
| | - Achille Binyang
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon.
| | - Tatiane Assatse
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon.
| | - Billy Tene-Fossog
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
| | - Magellan Tchouakui
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon.
| | - Daniel Nguete Nguiffo
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon.
| | - Helen Irving
- Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
| | - Cyrille Ndo
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
- Malaria Research Laboratory, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon.
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon.
| | - Parfait Awono-Ambene
- Malaria Research Laboratory, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon.
| | - Charles S Wondji
- Centre for Research in Infectious Diseases (CRID), P.O. BOX 13591, Yaoundé, Cameroon.
- Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
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Malathion-filled trilayer polyolefin film for malaria vector control. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 96:419-425. [PMID: 30606551 DOI: 10.1016/j.msec.2018.11.057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 10/17/2018] [Accepted: 11/27/2018] [Indexed: 11/20/2022]
Abstract
The emergence of pyrethroid resistance in mosquitoes is complicating malaria elimination efforts in Africa and alternative insecticides have to be considered for indoor residual spray. Unfortunately, the high volatility of WHO-approved organophosphate alternatives, e.g. malathion, translates into an early loss of residual efficacy. This laboratory study explored the concept of trilayer films as potential wall or ceiling linings. In the proposed design, the fugitive liquid insecticide is trapped in an inner core layer. The two sheath layers act as low-permeability membranes controlling the release of the insecticide. The concept was explored using poly(ethylene-co-vinyl acetate) (EVA) and low density polyethylene (LDPE) as core and sheath polymers respectively. The polarity of the EVA polymer matrix allowed incorporation of substantial quantities (up to 30 wt%) of malathion. The low polarity of the LDPE provided the necessary barrier properties and, in addition, allowed film blowing to be conducted at relatively low processing temperatures. Trilayer films containing about 6 wt% malathion were prepared on a film blowing line. Scanning electron microscopy confirmed the trilayer film structure. Confocal Raman microscopy studies revealed a malathion concentration gradient across the thickness of the polyethylene layers. Mass loss measurements and FTIR spectroscopy studies showed that the malathion release followed first-order kinetics. Bioassays, on samples aged at 22 °C, indicated that the residual efficacy against mosquitoes can be maintained for up to about six months. This suggests that trilayer films impregnated with organophosphates, may have potential as alternative mosquito control interventions in pyrethroid resistant settings.
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Ndo C, Poumachu Y, Metitsi D, Awono-Ambene HP, Tchuinkam T, Gilles JLR, Bourtzis K. Isolation and characterization of a temperature-sensitive lethal strain of Anopheles arabiensis for SIT-based application. Parasit Vectors 2018; 11:659. [PMID: 30583745 PMCID: PMC6304777 DOI: 10.1186/s13071-018-3216-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background Malaria is still a global health problem and vector control is the cornerstone of disease control strategies using indoor residual insecticide spraying (IRS) and insecticide-treated nets. The situation is becoming acute with widespread resistance to the limited arsenal of available insecticide classes. Therefore, new and innovative tools to reduce Plasmodium transmission are in need and this situation raised considerable interest in using sterile insect technique (SIT) against human pest insects, particularly Anopheles malaria vectors. When considering a mosquito release programme, one of the first issues to be addressed is how to eliminate/separate the hematophagous vector females. In this paper, we report the development and evaluation of an Anopheles arabiensis temperature-sensitive lethal (tsl) strain towards its potential use for the development of a genetic sexing strain (GSS). Anopheles arabiensis male mosquitoes originated from North Cameroon were treated with 0.05% ethyl methanesulfonate (EMS). The mutagen was added to 10% sucrose solution and mosquitoes fed ad-libitum for 24h and 48h on a cotton wool soaked with sucrose-mutagen solution placed at the top of the cup. Treated males were then allowed to mate with wild virgin females and their progenies were screened for heat sensitivity from F3 to F8, until the isolation and establishment of a tsl strain which was further characterized by assessing its productivity (fecundity and fertility), larval development, adult longevity as well as nature and inheritance pattern of the tsl. Results Observations showed that the number of eggs laid and their hatch rate were similar between females that mated with mutagenized males and those from the control suggesting that mutagenesis didn't affect An. arabiensis male fecundity and fertility. At F3, fourteen isofemale families out of 88 tested, which showed mortalities ranged between 50 and 80 %, were selected as lines potentially containing a tsl mutation. From F4 to F8, a tsl strain was isolated and established by screening L1 larvae at 41°C for 3 hours. This strain showed similar life history traits compared to the wild type strain in terms of fertility, larval development time and adult's emergence. Crossing experiments to further assess the nature and inheritance pattern of the tsl phenotype showed that it is due to a recessive allele located on an autosome. Conclusion The successful establishment of the An. arabiensis tsl strain is a valuable tool towards the development of a GSS for SIT applications against this species. This will be done by induction of a Y-autosome translocation to link the wild-type allele to the Y chromosome in such manner that males are wild-type (temperature resistant) and females are mutant (temperature sensitive).
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Affiliation(s)
- Cyrille Ndo
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), P.O Box 288, Yaoundé, Cameroon. .,Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon. .,Centre for Research in Infectious Diseases (CRID), P.O Box 13591, Yaoundé, Cameroon.
| | - Yacouba Poumachu
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), P.O Box 288, Yaoundé, Cameroon.,Vector Borne Parasitic and Infectious diseases Unit of the Laboratory of Applied Biology and Ecology (VBID-LABEA), Departement of Animal Biology, Faculty of Sciences of the University of Dschang, P.O Box 067, Dschang, Cameroon
| | - Danale Metitsi
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), P.O Box 288, Yaoundé, Cameroon.,Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Herman Parfait 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, Cameroon
| | - Timoléon Tchuinkam
- Vector Borne Parasitic and Infectious diseases Unit of the Laboratory of Applied Biology and Ecology (VBID-LABEA), Departement of Animal Biology, Faculty of Sciences of the University of Dschang, P.O Box 067, Dschang, Cameroon
| | - Jeremie Lionnel Roger Gilles
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Technique in Food and Agriculture, Vienna, Austria
| | - Kostas Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Technique in Food and Agriculture, Vienna, Austria
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Transcriptomic meta-signatures identified in Anopheles gambiae populations reveal previously undetected insecticide resistance mechanisms. Nat Commun 2018; 9:5282. [PMID: 30538253 PMCID: PMC6290077 DOI: 10.1038/s41467-018-07615-x] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 11/12/2018] [Indexed: 12/01/2022] Open
Abstract
Increasing insecticide resistance in malaria-transmitting vectors represents a public health threat, but underlying mechanisms are poorly understood. Here, a data integration approach is used to analyse transcriptomic data from comparisons of insecticide resistant and susceptible Anopheles populations from disparate geographical regions across the African continent. An unbiased, integrated analysis of this data confirms previously described resistance candidates but also identifies multiple novel genes involving alternative resistance mechanisms, including sequestration, and transcription factors regulating multiple downstream effector genes, which are validated by gene silencing. The integrated datasets can be interrogated with a bespoke Shiny R script, deployed as an interactive web-based application, that maps the expression of resistance candidates and identifies co-regulated transcripts that may give clues to the function of novel resistance-associated genes. Increasing insecticide resistance of mosquitoes represents a public health threat, and underlying mechanisms are poorly understood. Here, Ingham et al. identify putative insecticide resistance genes in Anopheles gambiae populations across Africa and develop a web-based application that maps their expression.
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21
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Liang ZK, Pang R, Dong Y, Sun ZX, Ling Y, Zhang WQ. Identification of SNPs involved in regulating a novel alternative transcript of P450 CYP6ER1 in the brown planthopper. INSECT SCIENCE 2018; 25:726-738. [PMID: 28459131 DOI: 10.1111/1744-7917.12472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 03/10/2017] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
Cytochrome P450-mediated metabolic resistance is one of the major mechanisms involved in insecticide resistance. Although the up-regulation of cytochrome P450 plays a vital role in insecticide metabolism, the molecular basis for the transcriptional regulation of cytochrome P450 remains largely unknown. The P450 gene CYP6ER1, has been reported to confer imidacloprid resistance to the brown planthopper, Nilaparvata lugens. Here, we identified a novel alternative transcript of CYP6ER1 (transcript A2) that had different expression patterns between resistant and susceptible populations, and was more stable after insecticide induction. The promoter of this transcript was sequenced and multiple single nucleotide polymorphisms (SNPs) were detected in individuals from susceptible and resistant field-collected populations. Resistant alleles of four SNPs were found to significantly enhance the promoter activity of the CYP6ER1 transcript A2. Electrophoretic mobility shift assays (EMSAs) revealed that these SNPs might regulate the binding of transcription factors to the promoter. Our findings provide novel evidence regarding the transcriptional regulation of a metabolic resistance-related gene and may be useful to understand the resistance mechanism of N. lugens in the field.
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Affiliation(s)
- Zhi-Kun Liang
- State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China
| | - Rui Pang
- State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China
| | - Yi Dong
- State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China
| | - Zhong-Xiang Sun
- State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China
| | - Yan Ling
- Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Wen-Qing Zhang
- State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China
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22
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Isaacs AT, Mawejje HD, Tomlinson S, Rigden DJ, Donnelly MJ. Genome-wide transcriptional analyses in Anopheles mosquitoes reveal an unexpected association between salivary gland gene expression and insecticide resistance. BMC Genomics 2018; 19:225. [PMID: 29587635 PMCID: PMC5870100 DOI: 10.1186/s12864-018-4605-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 03/14/2018] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND To combat malaria transmission, the Ugandan government has embarked upon an ambitious programme of indoor residual spraying (IRS) with a carbamate class insecticide, bendiocarb. In preparation for this campaign, we characterized bendiocarb resistance and associated transcriptional variation among Anopheles gambiae s.s. mosquitoes from two sites in Uganda. RESULTS Gene expression in two mosquito populations displaying some resistance to bendiocarb (95% and 79% An. gambiae s.l. WHO tube bioassay mortality in Nagongera and Kihihi, respectively) was investigated using whole-genome microarrays. Significant overexpression of several genes encoding salivary gland proteins, including D7r2 and D7r4, was detected in mosquitoes from Nagongera. In Kihihi, D7r4, two detoxification-associated genes (Cyp6m2 and Gstd3) and an epithelial serine protease were among the genes most highly overexpressed in resistant mosquitoes. Following the first round of IRS in Nagongera, bendiocarb-resistant mosquitoes were collected, and real-time quantitative PCR analyses detected significant overexpression of D7r2 and D7r4 in resistant mosquitoes. A single nucleotide polymorphism located in a non-coding transcript downstream of the D7 genes was found at a significantly higher frequency in resistant individuals. In silico modelling of the interaction between D7r4 and bendiocarb demonstrated similarity between the insecticide and serotonin, a known ligand of D7 proteins. A meta-analysis of published microarray studies revealed a recurring association between D7 expression and insecticide resistance across Anopheles species and locations. CONCLUSIONS A whole-genome microarray approach identified an association between novel insecticide resistance candidates and bendiocarb resistance in Uganda. In addition, a single nucleotide polymorphism associated with this resistance mechanism was discovered. The use of such impartial screening methods allows for discovery of resistance candidates that have no previously-ascribed function in insecticide binding or detoxification. Characterizing these novel candidates will broaden our understanding of resistance mechanisms and yield new strategies for combatting widespread insecticide resistance among malaria vectors.
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Affiliation(s)
- Alison T Isaacs
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
| | | | - Sean Tomlinson
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Daniel J Rigden
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - Martin J Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK.,Malaria Programme, Wellcome Trust Sanger Institute, Cambridge, UK
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Ismail BA, Kafy HT, Sulieman JE, Subramaniam K, Thomas B, Mnzava A, Abu Kassim NF, Ahmad AH, Knox TB, Kleinschmidt I, Donnelly MJ. Temporal and spatial trends in insecticide resistance in Anopheles arabiensis in Sudan: outcomes from an evaluation of implications of insecticide resistance for malaria vector control. Parasit Vectors 2018; 11:122. [PMID: 29499751 PMCID: PMC5834846 DOI: 10.1186/s13071-018-2732-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Accepted: 02/20/2018] [Indexed: 11/10/2022] Open
Abstract
Background Long-lasting insecticidal nets (LLINs) (with pyrethroids) and indoor residual spraying (IRS) are the cornerstones of the Sudanese malaria control program. Insecticide resistance to the principal insecticides in LLINs and IRS is a major concern. This study was designed to monitor insecticide resistance in Anopheles arabiensis from 140 clusters in four malaria-endemic areas of Sudan from 2011 to 2014. All clusters received LLINs, while half (n = 70), distributed across the four regions, had additional IRS campaigns. Methods Anopheles gambiae (s.l.) mosquitoes were identified to species level using PCR techniques. Standard WHO insecticide susceptibility bioassays were carried out to detect resistance to deltamethrin (0.05%), DDT (4%) and bendiocarb (0.1%). TaqMan assays were performed on random samples of deltamethrin-resistant phenotyped and pyrethrum spray collected individuals to determine Vgsc-1014 knockdown resistance mutations. Results Anopheles arabiensis accounted for 99.9% of any anopheline species collected across all sites. Bioassay screening indicated that mosquitoes remained susceptible to bendiocarb but were resistance to deltamethrin and DDT in all areas. There were significant increases in deltamethrin resistance over the four years, with overall mean percent mortality to deltamethrin declining from 81.0% (95% CI: 77.6–84.3%) in 2011 to 47.7% (95% CI: 43.5–51.8%) in 2014. The rate of increase in phenotypic deltamethrin-resistance was significantly slower in the LLIN + IRS arm than in the LLIN-only arm (Odds ratio 1.34; 95% CI: 1.02–1.77). The frequency of Vgsc-1014F mutation varied spatiotemporally with highest frequencies in Galabat (range 0.375–0.616) and New Halfa (range 0.241–0.447). Deltamethrin phenotypic-resistance correlated with Vgsc-1014F frequency. Conclusion Combining LLIN and IRS, with different classes of insecticide, may delay pyrethroid resistance development, but the speed at which resistance develops may be area-specific. Continued monitoring is vital to ensure optimal management and control. Electronic supplementary material The online version of this article (10.1186/s13071-018-2732-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bashir Adam Ismail
- Khartoum Malaria Free Initiative, PO Box 1517, Khartoum, Khartoum State, Sudan. .,School of Biological Sciences, Universiti Sains Malaysia, 11800, Minden, Pulau Penang, Malaysia.
| | - Hmooda Toto Kafy
- School of Biological Sciences, Universiti Sains Malaysia, 11800, Minden, Pulau Penang, Malaysia.,Integrated Vector Management Unit, Federal Ministry of Health, PO Box 303, Khartoum, Sudan
| | - Jihad Eltaher Sulieman
- Sennar Malaria Research and Training Centre, Federal Ministry of Health, PO Box 303, Sennar, Sudan
| | - Krishanthi Subramaniam
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Brent Thomas
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Abraham Mnzava
- African Leaders Malaria Alliance (ALMA), 14 Kanisa Road, Corridor Area, P.O. Box 1973, Arusha, Tanzania
| | - Nur Faeza Abu Kassim
- School of Biological Sciences, Universiti Sains Malaysia, 11800, Minden, Pulau Penang, Malaysia
| | - Abu Hassan Ahmad
- School of Biological Sciences, Universiti Sains Malaysia, 11800, Minden, Pulau Penang, Malaysia
| | - Tessa B Knox
- Global Malaria Programme, World Health Organization, Geneva, Switzerland
| | - Immo Kleinschmidt
- MRC Tropical Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Martin J Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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Silva GLD, Pereira TN, Ferla NJ, Silva OSD. The impact of insecticides management linked with resistance expression in Anopheles spp. populations. CIENCIA & SAUDE COLETIVA 2018; 21:2179-88. [PMID: 27383351 DOI: 10.1590/1413-81232015217.00922015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 06/11/2015] [Indexed: 11/22/2022] Open
Abstract
The resistance of some species of Anopheles to chemical insecticides is spreading quickly throughout the world and has hindered the actions of prevention and control of malaria. The main mechanism responsible for resistance in these insects appears to be the target site known as knock-down resistance (kdr), which causes mutations in the sodium channel. Even so, many countries have made significant progress in the prevention of malaria, focusing largely on vector control through long-lasting insecticide nets (LLINs), indoor residual spraying and (IRS) of insecticides. The objective of this review is to contribute with information on the more applied insecticides for the control of the main vectors of malaria, its effects, and the different mechanisms of resistance. Currently it is necessary to look for others alternatives, e.g. biological control and products derived from plants and fungi, by using other organisms as a possible regulator of the populations of malaria vectors in critical outbreaks.
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Affiliation(s)
- Guilherme Liberato da Silva
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal do Rio Grande do Sul. R. Sarmento Leite 500, Centro Histórico. 90050-170 Porto Alegre RS Brasil.
| | - Thiago Nunes Pereira
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal do Rio Grande do Sul. R. Sarmento Leite 500, Centro Histórico. 90050-170 Porto Alegre RS Brasil.
| | - Noeli Juarez Ferla
- Laboratório de Acarologia, Museu de Ciências Naturais, Centro Universitário UNIVATES. Lajeado RS Brasil
| | - Onilda Santos da Silva
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal do Rio Grande do Sul. R. Sarmento Leite 500, Centro Histórico. 90050-170 Porto Alegre RS Brasil.
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Hemming-Schroeder E, Strahl S, Yang E, Nguyen A, Lo E, Zhong D, Atieli H, Githeko A, Yan G. Emerging Pyrethroid Resistance among Anopheles arabiensis in Kenya. Am J Trop Med Hyg 2018; 98:704-709. [PMID: 29363447 PMCID: PMC5930888 DOI: 10.4269/ajtmh.17-0445] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Vector control programs, particularly in the form of insecticide-treated bed nets (ITNs), are essential for achieving malaria elimination goals. Recent reports of increasing knockdown resistance (kdr) mutation frequencies for Anopheles arabiensis in Western Kenya heightens the concern on the future effectiveness of ITNs in Kenya. We examined resistance in An. arabiensis populations across Kenya through kdr mutations and World Health Organization–recommended bioassays. We detected two kdr alleles, L1014F and L1014S. Kdr mutations were found in five of the 11 study sites, with mutation frequencies ranging from 3% to 63%. In two Western Kenya populations, the kdr L1014F allele frequency was as high as 10%. The L1014S frequency was highest at Chulaimbo at 55%. Notably, the kdr L1014F mutation was found to be associated with pyrethroid resistance at Port Victoria, but kdr mutations were not significantly associated with resistance at Chulaimbo, which had the highest kdr mutation frequency among all sites. This study demonstrated the emerging pyrethroid resistance in An. arabiensis and that pyrethroid resistance may be related to kdr mutations. Resistance monitoring and management are urgently needed for this species in Kenya where resistance is emerging and its abundance is becoming predominant. Kdr mutations may serve as a biomarker for pyrethroid resistance in An. arabiensis.
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Affiliation(s)
| | - Stephanie Strahl
- Program in Public Health, University of California, Irvine, California
| | - Eugene Yang
- Program in Public Health, University of California, Irvine, California
| | - Amanda Nguyen
- Program in Public Health, University of California, Irvine, California
| | - Eugenia Lo
- Program in Public Health, University of California, Irvine, California
| | - Daibin Zhong
- Program in Public Health, University of California, Irvine, California
| | - Harrysone Atieli
- Centre for Vector Biology and Control Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Andrew Githeko
- Centre for Vector Biology and Control Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, California
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26
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Messenger LA, Shililu J, Irish SR, Anshebo GY, Tesfaye AG, Ye-Ebiyo Y, Chibsa S, Dengela D, Dissanayake G, Kebede E, Zemene E, Asale A, Yohannes M, Taffese HS, George K, Fornadel C, Seyoum A, Wirtz RA, Yewhalaw D. Insecticide resistance in Anopheles arabiensis from Ethiopia (2012-2016): a nationwide study for insecticide resistance monitoring. Malar J 2017; 16:469. [PMID: 29151024 PMCID: PMC5694167 DOI: 10.1186/s12936-017-2115-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 11/10/2017] [Indexed: 11/27/2022] Open
Abstract
Background Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) remain the cornerstones of malaria vector control. However, the development of insecticide resistance and its implications for operational failure of preventative strategies are of concern. The aim of this study was to characterize insecticide resistance among Anopheles arabiensis populations in Ethiopia and describe temporal and spatial patterns of resistance between 2012 and 2016. Methods Between 2012 and 2016, resistance status of An. arabiensis was assessed annually during the long rainy seasons in study sites from seven of the nine regions in Ethiopia. Insecticide resistance levels were measured with WHO susceptibility tests and CDC bottle bioassays using insecticides from four chemical classes (organochlorines, pyrethroids, organophosphates and carbamates), with minor variations in insecticides tested and assays conducted between years. In selected sites, CDC synergist assays were performed by pre-exposing mosquitoes to piperonyl butoxide (PBO). In 2015 and 2016, mosquitoes from DDT and deltamethrin bioassays were randomly selected, identified to species-level and screened for knockdown resistance (kdr) by PCR. Results Intense resistance to DDT and pyrethroids was pervasive across Ethiopia, consistent with historic use of DDT for IRS and concomitant increases in insecticide-treated net coverage over the last 15 years. Longitudinal resistance trends to malathion, bendiocarb, propoxur and pirimiphos-methyl corresponded to shifts in the national insecticide policy. By 2016, resistance to the latter two insecticides had emerged, with the potential to jeopardize future long-term effectiveness of vector control activities in these areas. Between 2015 and 2016, the West African (L1014F) kdr allele was detected in 74.1% (n = 686/926) of specimens, with frequencies ranging from 31 to 100% and 33 to 100% in survivors from DDT and deltamethrin bioassays, respectively. Restoration of mosquito susceptibility, following pre-exposure to PBO, along with a lack of association between kdr allele frequency and An. arabiensis mortality rate, both indicate metabolic and target-site mutation mechanisms are contributing to insecticide resistance. Conclusions Data generated by this study will strengthen the National Malaria Control Programme’s insecticide resistance management strategy to safeguard continued efficacy of IRS and other malaria control methods in Ethiopia. Electronic supplementary material The online version of this article (10.1186/s12936-017-2115-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Louisa A Messenger
- Entomology Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA, 30329-4027, USA.
| | - Josephat Shililu
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Seth R Irish
- Entomology Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA, 30329-4027, USA
| | - Gedeon Yohannes Anshebo
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Alemayehu Getachew Tesfaye
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Yemane Ye-Ebiyo
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Sheleme Chibsa
- U.S. Agency for International Development (USAID), Entoto Street, Addis Ababa, Ethiopia
| | - Dereje Dengela
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 4550 Montgomery Ave., Suite 800 North, Bethesda, MD, 20814, USA
| | | | - Estifanos Kebede
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Endalew Zemene
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Abebe Asale
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Mekonnen Yohannes
- Medical and Entomology Unit, Institute of Bio-Medical Sciences, College of Health Sciences, Mekelle University, Mek'ele, Ethiopia
| | - Hiwot Solomon Taffese
- National Malaria Control Programne, Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Kristen George
- President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Christen Fornadel
- President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Aklilu Seyoum
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 4550 Montgomery Ave., Suite 800 North, Bethesda, MD, 20814, USA
| | - Robert A Wirtz
- Entomology Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA, 30329-4027, USA
| | - Delenasaw Yewhalaw
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia.,Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia
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Yahouédo GA, Chandre F, Rossignol M, Ginibre C, Balabanidou V, Mendez NGA, Pigeon O, Vontas J, Cornelie S. Contributions of cuticle permeability and enzyme detoxification to pyrethroid resistance in the major malaria vector Anopheles gambiae. Sci Rep 2017; 7:11091. [PMID: 28894186 PMCID: PMC5593880 DOI: 10.1038/s41598-017-11357-z] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 08/18/2017] [Indexed: 11/09/2022] Open
Abstract
To tackle the problem of insecticide resistance, all resistance mechanisms need to be studied. This study investigated the involvement of the cuticle in pyrethroid resistance in a strain of Anopheles gambiae, MRS, free of kdr mutations. Bioassays revealed MRS to be resistant to pyrethroids and DDT, indicated by increasing knockdown times and resistance ratios. Moreover, biochemical analysis indicated that metabolic resistance based on enhanced CYP450 activity may also play a role. Insecticide penetration assays showed that there were significantly lower amounts of insecticide in the MRS strain than in the susceptible control. Analysis of the levels of the selected transcripts by qPCR showed that CYP6M2, a major pyrethroid metaboliser, CYP4G16, a gene implicated in resistance via its contribution to the biosynthesis of elevated epicuticular hydrocarbons that delay insecticide uptake, and the cuticle genes CPAP3-E and CPLCX1 were upregulated after insecticide exposure. Other metabolic (CYP6P3, GSTe2) and cuticle (CPLCG3, CPRs) genes were also constitutively upregulated. Microscopic analysis showed that the cuticle layers of the MRS strain were significantly thicker than those of the susceptible strain. This study allowed us to assess the contribution made by the cuticle and metabolic mechanisms to pyrethroid resistance in Anopheles gambiae without target-site mutations.
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Affiliation(s)
- Gildas A Yahouédo
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR - IRD224, CNRS 5290, Montpellier, France.
| | - Fabrice Chandre
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR - IRD224, CNRS 5290, Montpellier, France
| | - Marie Rossignol
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR - IRD224, CNRS 5290, Montpellier, France
| | - Carole Ginibre
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR - IRD224, CNRS 5290, Montpellier, France
| | - Vasileia Balabanidou
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, 70013, Greece.,Department of Biology, University of Crete, Vassilika Vouton, Heraklion, 70013, Greece
| | - Natacha Garcia Albeniz Mendez
- Walloon Agricultural Research Centre (CRA-W), Agriculture and Natural Environment Department (D3), Plant Protection Products and Biocides, Physico-chemistry and Residues Unit (U10), B-5030, Gembloux, Belgium
| | - Olivier Pigeon
- Walloon Agricultural Research Centre (CRA-W), Agriculture and Natural Environment Department (D3), Plant Protection Products and Biocides, Physico-chemistry and Residues Unit (U10), B-5030, Gembloux, Belgium
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, 70013, Greece.,Department of Biology, University of Crete, Vassilika Vouton, Heraklion, 70013, Greece
| | - Sylvie Cornelie
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR - IRD224, CNRS 5290, Montpellier, France
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Alemayehu E, Asale A, Eba K, Getahun K, Tushune K, Bryon A, Morou E, Vontas J, Van Leeuwen T, Duchateau L, Yewhalaw D. Mapping insecticide resistance and characterization of resistance mechanisms in Anopheles arabiensis (Diptera: Culicidae) in Ethiopia. Parasit Vectors 2017; 10:407. [PMID: 28865490 PMCID: PMC5581456 DOI: 10.1186/s13071-017-2342-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 08/22/2017] [Indexed: 12/05/2022] Open
Abstract
Background The emergence and spread of insecticide resistance in the major African malaria vectors Anopheles gambiae (s.s.) and An. arabiensis may compromise the current vector control interventions and threatens the global malaria control and elimination efforts. Methods Insecticide resistance was monitored in several study sites in Ethiopia from 2013 to 2015 using papers impregnated with discriminating concentrations of DDT, deltamethrin, bendiocarb, propoxur, malathion, fenitrothion and pirimiphos-methyl, following the WHO insecticide susceptibility test procedure. Mosquitoes sampled from different localities for WHO bioassay were morphologically identified as An. gambiae (s.l.) using standard taxonomic keys. Samples were identified to species using species-specific polymerase chain reaction (PCR) and screened for the presence of target site mutations L1014F, L1014S and N1575Y in the voltage gated sodium channel (VGSC) gene and G119S in the acethylcholinesterase (AChE) gene using allele-specific PCR. Biochemical assays were performed to assess elevated levels of acetylcholinesterases, carboxylcholinesterases, glutathione-S-transferases (GSTs) and cytochrome P450s monooxygenases in wild populations of An. arabiensis, compared to the fully susceptible Sekoru An. arabiensis laboratory strain. Results Populations of An. arabiensis were resistant to DDT and deltamethrin but were susceptible to fenitrothion in all the study sites. Reduced susceptibility to malathion, pirimiphos-methyl, propoxur and bendiocarb was observed in some of the study sites. Knockdown resistance (kdr L1014F) was detected in all mosquito populations with allele frequency ranging from 42 to 91%. Elevated levels of glutathione-S-transferases (GSTs) were detected in some of the mosquito populations. However, no elevated levels of monooxygenases and esterases were detected in any of the populations assessed. Conclusions Anopheles arabiensis populations from all surveyed sites in Ethiopia exhibited resistance against DDT and pyrethroids. Moreover, some mosquito populations exhibited resistance to propoxur and possible resistance to bendiocarb. Target site mutation kdr L1014F was detected in all mosquito populations while elevated levels of glutathione-S-transferases (GSTs) was detected in some mosquito populations. The reduced susceptibility of An. arabiensis to propoxur and bendiocarb, which are currently used for indoor residual spraying (IRS) in Ethiopia, calls for continuous resistance monitoring, in order to plan and implement evidence based insecticide resistance management. Electronic supplementary material The online version of this article (10.1186/s13071-017-2342-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Eba Alemayehu
- Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia.,Department of Comparative Physiology and Biometrics, University of Ghent, Ghent, Belgium
| | - Abebe Asale
- Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Kasahun Eba
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Kefelegn Getahun
- Department of Geography and Environmental Studies, Jimma University, Jimma, Ethiopia
| | - Kora Tushune
- Department of Health Services Management, College of Health Sciences, Jimma University, Jimma, Ethiopia
| | - Astrid Bryon
- Department of Crop Protection, Ghent University, Ghent, Belgium
| | - Evangelia Morou
- Department of Biology, University of Crete, Heraklion, Greece.,Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece.,Department of Crop Science, Pesticide Science Lab, Agricultural University of Athens, Athens, Greece
| | - Thomas Van Leeuwen
- Department of Crop Protection, Ghent University, Ghent, Belgium.,Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Luc Duchateau
- Department of Comparative Physiology and Biometrics, University of Ghent, Ghent, Belgium
| | - Delenasaw Yewhalaw
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia. .,Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia.
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Ingham VA, Pignatelli P, Moore JD, Wagstaff S, Ranson H. The transcription factor Maf-S regulates metabolic resistance to insecticides in the malaria vector Anopheles gambiae. BMC Genomics 2017; 18:669. [PMID: 28854876 PMCID: PMC5577768 DOI: 10.1186/s12864-017-4086-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/24/2017] [Indexed: 11/16/2022] Open
Abstract
Background Malaria control in Africa is dependent upon the use insecticides but intensive use of a limited number of chemicals has led to resistance in mosquito populations. Increased production of enzymes that detoxify insecticides is one of the most potent resistance mechanisms. Several metabolic enzymes have been implicated in insecticide resistance but the processes controlling their expression have remained largely elusive. Results Here, we show that the transcription factor Maf-S regulates expression of multiple detoxification genes, including the key insecticide metabolisers CYP6M2 and GSTD1 in the African malaria vector Anopheles gambiae. Attenuation of this transcription factor through RNAi induced knockdown reduced transcript levels of these effectors and significantly increased mortality after exposure to the pyrethroid insecticides and DDT (permethrin: 9.2% to 19.2% (p = 0.015), deltamethrin: 3.9% to 21.6% (p = 0.036) and DDT: 1% to 11.7% (p = <0.01), whilst dramatically decreasing mortality induced by the organophosphate malathion (79.6% to 8.0% (p = <0.01)). Additional genes regulated by Maf-S were also identified providing new insight into the role of this transcription factor in insects. Conclusion Maf-S is a key regulator of detoxification genes in Anopheles mosquitoes. Disrupting this transcription factor has opposing effects on the mosquito’s response to different insecticide classes providing a mechanistic explanation to the negative cross resistance that has been reported between pyrethroids and organophosphates. Electronic supplementary material The online version of this article (10.1186/s12864-017-4086-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Victoria A Ingham
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA.
| | - Patricia Pignatelli
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA
| | - Jonathan D Moore
- Earlham Institute, Norwich Research Park Innovation Centre, Colney Lane, Norwich, England, NR4 7UH
| | - Simon Wagstaff
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA
| | - Hilary Ranson
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA.
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Genome-Wide Transcription and Functional Analyses Reveal Heterogeneous Molecular Mechanisms Driving Pyrethroids Resistance in the Major Malaria Vector Anopheles funestus Across Africa. G3-GENES GENOMES GENETICS 2017; 7:1819-1832. [PMID: 28428243 PMCID: PMC5473761 DOI: 10.1534/g3.117.040147] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Pyrethroid resistance in malaria vector, An. funestus is increasingly reported across Africa, threatening the sustainability of pyrethroid-based control interventions, including long lasting insecticidal nets (LLINs). Managing this problem requires understanding of the molecular basis of the resistance from different regions of the continent, to establish whether it is being driven by a single or independent selective events. Here, using a genome-wide transcription profiling of pyrethroid resistant populations from southern (Malawi), East (Uganda), and West Africa (Benin), we investigated the molecular basis of resistance, revealing strong differences between the different African regions. The duplicated cytochrome P450 genes (CYP6P9a and CYP6P9b) which were highly overexpressed in southern Africa are not the most upregulated in other regions, where other genes are more overexpressed, including GSTe2 in West (Benin) and CYP9K1 in East (Uganda). The lack of directional selection on both CYP6P9a and CYP6P9b in Uganda in contrast to southern Africa further supports the limited role of these genes outside southern Africa. However, other genes such as the P450 CYP9J11 are commonly overexpressed in all countries across Africa. Here, CYP9J11 is functionally characterized and shown to confer resistance to pyrethroids and moderate cross-resistance to carbamates (bendiocarb). The consistent overexpression of GSTe2 in Benin is coupled with a role of allelic variation at this gene as GAL4-UAS transgenic expression in Drosophila flies showed that the resistant 119F allele is highly efficient in conferring both DDT and permethrin resistance than the L119. The heterogeneity in the molecular basis of resistance and cross-resistance to insecticides in An. funestus populations throughout sub-Saharan African should be taken into account in designing resistance management strategies.
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31
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Venter N, Oliver SV, Muleba M, Davies C, Hunt RH, Koekemoer LL, Coetzee M, Brooke BD. Benchmarking insecticide resistance intensity bioassays for Anopheles malaria vector species against resistance phenotypes of known epidemiological significance. Parasit Vectors 2017; 10:198. [PMID: 28427447 PMCID: PMC5397746 DOI: 10.1186/s13071-017-2134-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 04/11/2017] [Indexed: 11/22/2022] Open
Abstract
Background Insecticide use via indoor residual spraying (IRS) or treated nets is the primary method for controlling malaria vector populations. The incidence of insecticide resistance in vector populations is burgeoning globally making resistance management key to the design of effective malaria control and elimination strategies. Vector populations can be assessed for insecticide resistance using a binary (susceptible or resistant) classification based on the use of the standard WHO insecticide susceptibility assay for adult anopheline mosquitoes. However, the recent scaling up of vector control activities has necessitated a revision of the WHO bioassay protocol to include the production of information that not only diagnoses resistance but also gives information on the intensity of expression of resistance phenotypes detected. This revised protocol is expected to inform on the range of resistance phenotypes in a target vector population using discriminating/diagnostic insecticide concentrations (DC) as well as their potential operational significance using 5× DC and 10× DC assays. The aim of this project was to use the revised protocol to assess the intensity of pyrethroid resistance in a range of insecticide resistant Anopheles strains with known resistance mechanisms and for which there is evidence of operational significance in the field setting from which these colonies were derived. Methods Diagnostic concentration (DC) bioassays followed by 5× DC and 10× DC assays using the pyrethroid insecticides permethrin and deltamethrin were conducted according to the standard WHO bioassay method against pyrethroid resistant laboratory strains of Anopheles funestus, An. arabiensis and An. gambiae. Results Low to moderate resistance intensities were recorded for the An. arabiensis and An. gambiae strains while moderate to high intensities were recorded for the An. funestus strains. Conclusions It is evident that resistance intensity assays can add predictive value to the decision making process in vector control settings, although more so in an IRS setting and especially when bench-marked against resistance phenotypes of known operational significance.
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Affiliation(s)
- Nelius Venter
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Shȕné V Oliver
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | - Craig Davies
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Richard H Hunt
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Lizette L Koekemoer
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Maureen Coetzee
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Basil D Brooke
- Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa. .,Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Yahouédo GA, Cornelie S, Djègbè I, Ahlonsou J, Aboubakar S, Soares C, Akogbéto M, Corbel V. Dynamics of pyrethroid resistance in malaria vectors in southern Benin following a large scale implementation of vector control interventions. Parasit Vectors 2016; 9:385. [PMID: 27378358 PMCID: PMC4932690 DOI: 10.1186/s13071-016-1661-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 06/22/2016] [Indexed: 01/13/2023] Open
Abstract
Background Large-scale implementation of Indoor Residual Spraying and Insecticide Treated Nets has been implemented in Plateau Department, Benin between 2011 and 2014. The purpose of this study was to monitor the frequency and mechanisms of pyrethroid resistance in malaria vectors following the implementation of vector control tools for malaria prevention. Methods Anopheles larvae were collected in 13 villages twice a year from 2012 to 2014. WHO tube tests were used to assess the phenotypic resistance of each population to 0.05 % deltamethrin. Sibling species within Anopheles gambiae complex were identified by PCR techniques. Taqman and biochemical assays were performed to identify the presence of kdr mutations in individual mosquitoes and to detect any increase in the activity of enzymes putatively involved in insecticide metabolism (oxidases, esterase and glutathione-S-transferases). Quantitative real time PCR was used to measure the expression of three metabolic genes involved in pyrethroid resistance (CYP6P3, CYP6M2 and GSTD3). Results Anopheles populations showed < 90 % mortality to deltamethrin in all villages and at all time points. The 1014 F kdr allele frequency was close to fixation (> 0.9) over the sampling periods in both An. gambiae and An. coluzzii. Biochemical assays showed higher activities of alpha esterase and GST in field malaria vector populations compared to susceptible mosquitoes. qPCR assays showed a significant increase of CYP6P3, CYP6M2 GSTD3 expression in An. gambiae after a three-year implementation of LLINs. Conclusion The study confirmed that deltamethrin resistance is widespread in malaria vectors in Southern Benin. We suspect that the increase in deltamethrin resistance between 2012 and 2014 resulted from an increased expression of metabolic detoxification genes (CYP6M2 and CYP6P3) rather than from kdr mutations. It is urgent to evaluate further the impact of metabolic resistance on the efficacy of vector control interventions using pyrethroid insecticides.
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Affiliation(s)
- Gildas A Yahouédo
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR UM1-UM2 - CNRS 5290 - IRD 224, Montpellier, France. .,Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.
| | - Sylvie Cornelie
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR UM1-UM2 - CNRS 5290 - IRD 224, Montpellier, France.,Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Innocent Djègbè
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR UM1-UM2 - CNRS 5290 - IRD 224, Montpellier, France.,Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Justine Ahlonsou
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Sidick Aboubakar
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | | | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Vincent Corbel
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR UM1-UM2 - CNRS 5290 - IRD 224, Montpellier, France.,Department of Entomology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Rd, Lat Yao Chatuchak, Bangkok, 10900, Thailand
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Randriamaherijaona S, Velonirina HJ, Boyer S. Susceptibility status of Anopheles arabiensis (Diptera: Culicidae) commonly used as biological materials for evaluations of malaria vector control tools in Madagascar. Malar J 2016; 15:338. [PMID: 27364163 PMCID: PMC4929764 DOI: 10.1186/s12936-016-1406-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/20/2016] [Indexed: 11/10/2022] Open
Abstract
Background Madagascar is a malaria-endemic country with an increase in cases in recent years. In vector control using insecticide, a susceptible strain is necessary to evaluate insecticide efficacy, either for spraying or on nets. The susceptibility of Anopheles arabiensis from Antananarivo, Madagascar to two organophosphate, three pyrethroid, two carbamate, and one organochlorine insecticides was investigated. Since 2010, An. arabiensis strain has been maintained away from insecticide source during 110 generations with optimal insectarium conditions. Methods Bioassay were performed on adult mosquitoes to assess the susceptibility of An. arabiensis to insecticide-impregnated papers (malathion 5 %, fenitrothion 1 %, deltamethrin 0.05 %, permethrin 0.75 %, alphacypermethrin 0.05 %, bendiocarb 0.1 %, propoxur 0.01 %, and DDT 4 %) following World Health Organization Pesticide Evaluation Scheme guidelines. Bioassay using Center for Disease Control bottle tests were also used to detect mortality. Molecular assay were carried out to detect the presence of knock down resistance (kdr) mutation using PCR techniques. Results Anopheles arabiensis is fully susceptible with 100 % mortality to malathion, fenitrothion, deltamethrin, permethrin, alphacypermethrin, bendiocarb, propoxur, and DDT. No kdr gene was detected using PCR method. Conclusion The strain An. arabiensis maintained in the insectarium of Institut Pasteur de Madagascar is a fully susceptible strain and can be used for insecticide evaluation.
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Affiliation(s)
- Sanjiarizaha Randriamaherijaona
- Unité d'Entomologie Médicale, Institut Pasteur de Madagascar, Antananarivo, Madagascar. .,Ecole Doctorale Science de la vie et de l'environnement, Faculté des Sciences, Université d'Antananarivo, Antananarivo, Madagascar.
| | | | - Sébastien Boyer
- Unité d'Entomologie Médicale, Institut Pasteur de Madagascar, Antananarivo, Madagascar
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Etang J, Mbida Mbida A, Ntonga Akono P, Binyang J, Eboumbou Moukoko CE, Lehman LG, Awono-Ambene P, Talipouo A, Ekoko Eyisab W, Tagne D, Tchoffo R, Manga L, Mimpfoundi R. Anopheles coluzzii larval habitat and insecticide resistance in the island area of Manoka, Cameroon. BMC Infect Dis 2016; 16:217. [PMID: 27207560 PMCID: PMC4875715 DOI: 10.1186/s12879-016-1542-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 05/05/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The effectiveness of Long-Lasting Insecticidal Nets and Indoor Residual Spraying in malaria vector control is threatened by vector resistance to insecticides. Knowledge of mosquito habitats and patterns of insecticide resistance would facilitate the development of appropriate vector control strategies. Therefore, we investigated An. coluzzii larval habitats and resistance to insecticides in the Manoka rural island area compared with the Youpwe suburban inland area, in Douala VI and II districts respectively. METHODS Anopheline larvae and pupae were collected from open water bodies in December 2013 and April 2014 and reared until adult emergence. Two to four day old emerging females were morphologically identified as belonging to the An. gambiae complex and used for WHO susceptibility tests with 4 % DDT, 0.75 % permethrin, and 0.05 % deltamethrin, with or without piperonyl butoxide (PBO) synergist. Control and surviving specimens were identified down to the species using a PCR-RFLP method. Survivors were genotyped for kdr L1014 mutations using Hot Oligonucleotide Ligation Assay. RESULTS In both study sites, ponds, residual puddles, boats, and drains were identified as the major An. gambiae s.l. larval habitats. A total of 1397 females, including 784 specimens from Manoka and 613 from Youpwe, were used for resistance testing. The two mosquito populations displayed resistance to DDT, permethrin and deltamethrin, with variable mortality rates from 1 % to 90 %. The knock-down times were also significantly increased (at least 2.8 fold). Pre-exposure of mosquitoes to PBO did not impact on their mortality to DDT, conversely the mortality rates to permethrin and deltamethrin were significantly increased (7.56 ≤ X(2) ≤ 48.63, df = 1, p < 0.01), suggesting involvement of P450 oxidases in pyrethroid resistance. A subsample of 400 An. gambiae s.l. specimens including 280 control and 120 survivors from bioassays were all found to be An. coluzzii species. Only the kdr 1014 F mutation was found in survivors, with 88.5 % (N = 76) and 75 % (N = 44) frequencies in Youpwe and Manoka respectively. CONCLUSION This is the first report of An. coluzzii resistance to insecticides in an insular area in Cameroon. Since permanent larval habitats have been identified, larval source management strategies may be trialed in this area as complementary vector control interventions.
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Affiliation(s)
- Josiane Etang
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), B.P. 288, Yaoundé, Cameroun. .,Biological Sciences Unit, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, P.O.Box 2701, Douala, Cameroon.
| | - Arthur Mbida Mbida
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Patrick Ntonga Akono
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Jerome Binyang
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Carole Else Eboumbou Moukoko
- Biological Sciences Unit, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, P.O.Box 2701, Douala, Cameroon.,Pôle d'Excellence en Epidémiologie du Paludisme, Service d'Epidémiologie et de Santé Publique, Centre Pasteur du Cameroun, B.P. 1274, Yaoundé, Cameroun
| | - Leopold Gustave Lehman
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Parfait Awono-Ambene
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), B.P. 288, Yaoundé, Cameroun
| | - Abdou Talipouo
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Wolfgang Ekoko Eyisab
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), B.P. 288, Yaoundé, Cameroun.,Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Darus Tagne
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Romeo Tchoffo
- Laboratory of Animal Biology and Physiology, Faculty of Science, University of Douala, P.O.Box 24157, Douala, Cameroon
| | - Lucien Manga
- World Health Organization, Regional office for Africa, P.O.Box 6, Cité Djoué, Brazzaville, Congo
| | - Remy Mimpfoundi
- Laboratory of General Biology, University of Yaounde I, P.O.Box 812, Yaounde, Cameroon
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Ibrahim SS, Riveron JM, Stott R, Irving H, Wondji CS. The cytochrome P450 CYP6P4 is responsible for the high pyrethroid resistance in knockdown resistance-free Anopheles arabiensis. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 68:23-32. [PMID: 26548743 PMCID: PMC4717123 DOI: 10.1016/j.ibmb.2015.10.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/27/2015] [Accepted: 10/27/2015] [Indexed: 05/04/2023]
Abstract
Pyrethroid insecticides are the front line vector control tools used in bed nets to reduce malaria transmission and its burden. However, resistance in major vectors such as Anopheles arabiensis is posing a serious challenge to the success of malaria control. Herein, we elucidated the molecular and biochemical basis of pyrethroid resistance in a knockdown resistance-free Anopheles arabiensis population from Chad, Central Africa. Using heterologous expression of P450s in Escherichia coli coupled with metabolism assays we established that the over-expressed P450 CYP6P4, located in the major pyrethroid resistance (rp1) quantitative trait locus (QTL), is responsible for resistance to Type I and Type II pyrethroid insecticides, with the exception of deltamethrin, in correlation with field resistance profile. However, CYP6P4 exhibited no metabolic activity towards non-pyrethroid insecticides, including DDT, bendiocarb, propoxur and malathion. Combining fluorescent probes inhibition assays with molecular docking simulation, we established that CYP6P4 can bind deltamethrin but cannot metabolise it. This is possibly due to steric hindrance because of the large vdW radius of bromine atoms of the dihalovinyl group of deltamethrin which docks into the heme catalytic centre. The establishment of CYP6P4 as a partial pyrethroid resistance gene explained the observed field resistance to permethrin, and its inability to metabolise deltamethrin probably explained the high mortality from deltamethrin exposure in the field populations of this Sudano-Sahelian An. arabiensis. These findings describe the heterogeneity in resistance towards insecticides, even from the same class, highlighting the need to thoroughly understand the molecular basis of resistance before implementing resistance management/control tools.
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Affiliation(s)
- Sulaiman S Ibrahim
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom.
| | - Jacob M Riveron
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom.
| | - Robert Stott
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom; Department of Health and Social Sciences, Leeds Beckett University, LS1 3HE, Leeds, United Kingdom.
| | - Helen Irving
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom.
| | - Charles S Wondji
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom.
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Chanda E, Ameneshewa B, Mihreteab S, Berhane A, Zehaie A, Ghebrat Y, Usman A. Consolidating strategic planning and operational frameworks for integrated vector management in Eritrea. Malar J 2015; 14:488. [PMID: 26630934 PMCID: PMC4668606 DOI: 10.1186/s12936-015-1022-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/26/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Contemporary malaria vector control relies on the use of insecticide-based, indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs). However, malaria-endemic countries, including Eritrea, have struggled to effectively deploy these tools due technical and operational challenges, including the selection of insecticide resistance in malaria vectors. This manuscript outlines the processes undertaken in consolidating strategic planning and operational frameworks for vector control to expedite malaria elimination in Eritrea. CASE DESCRIPTION The effort to strengthen strategic frameworks for vector control in Eritrea was the 'case' for this study. The integrated vector management (IVM) strategy was developed in 2010 but was not well executed, resulting in a rise in malaria transmission, prompting a process to redefine and relaunch the IVM strategy with integration of other vector borne diseases (VBDs) as the focus. The information sources for this study included all available data and accessible archived documentary records on malaria vector control in Eritrea. Structured literature searches of published, peer-reviewed sources using online, scientific, bibliographic databases, Google Scholar, PubMed and WHO, and a combination of search terms were utilized to gather data. The literature was reviewed and adapted to the local context and translated into the consolidated strategic framework. DISCUSSION In Eritrea, communities are grappling with the challenge of VBDs posing public health concerns, including malaria. The global fund financed the scale-up of IRS and LLIN programmes in 2014. Eritrea is transitioning towards malaria elimination and strategic frameworks for vector control have been consolidated by: developing an integrated vector management (IVM) strategy (2015-2019); updating IRS and larval source management (LSM) guidelines; developing training manuals for IRS and LSM; training of national staff in malaria entomology and vector control, including insecticide resistance monitoring techniques; initiating the global plan for insecticide resistance management; conducting needs' assessments and developing standard operating procedure for insectaries; developing a guidance document on malaria vector control based on eco-epidemiological strata, a vector surveillance plan and harmonized mapping, data collection and reporting tools. CONCLUSION Eritrea has successfully consolidated strategic frameworks for vector control. Rational decision-making remains critical to ensure that the interventions are effective and their choice is evidence-based, and to optimize the use of resources for vector control. Implementation of effective IVM requires proper collaboration and coordination, consistent technical and financial capacity and support to offer greater benefits.
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Affiliation(s)
- Emmanuel Chanda
- Vector Control Specialist/Consultant, Kamwala South, Lusaka, Zambia.
| | | | - Selam Mihreteab
- National Malaria Control Programme, Ministry of Health, Asmara, Eritrea.
| | - Araia Berhane
- Communicable Diseases and Control Division, Ministry of Health, Asmara, Eritrea.
| | - Assefash Zehaie
- World Health Organization, Eritrea Country Office, Asmara, Eritrea.
| | - Yohannes Ghebrat
- World Health Organization, Eritrea Country Office, Asmara, Eritrea.
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Wanjala CL, Zhou G, Mbugi J, Simbauni J, Afrane YA, Ototo E, Gesuge M, Atieli H, Githeko AK, Yan G. Insecticidal decay effects of long-lasting insecticide nets and indoor residual spraying on Anopheles gambiae and Anopheles arabiensis in Western Kenya. Parasit Vectors 2015; 8:588. [PMID: 26567915 PMCID: PMC4644290 DOI: 10.1186/s13071-015-1194-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 10/31/2015] [Indexed: 11/13/2022] Open
Abstract
Background Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) are the first-line tools for malaria prevention and control in Africa. Vector resistance to insecticides has been extensively studied, however the insecticidal effects of the nets and sprayed walls on pyrethroid resistant mosquitoes has not been studied thoroughly. We evaluated the bioefficacy of LLINs of different ages and lambda-cyhalothrin (ICON 10cs) on the sprayed mud walls for a period of time on malaria vector survivorship. Methods WHO tube bioassay was performed using diagnostic doses of lambda-cyhalothrin (0.05 %), permethrin (0.75 %) and deltamethrin (0.05 %). Cone bioassays were conducted on netting materials from 0 to 3 years old long-lasting insecticide-impregnated nets. Wall bioassays were performed monthly on mud slabs sprayed with lambdacyhalothrin over a period of seven months. All bioassays used An. gambiae mosquitoes collected from the field and the laboratory susceptible reference Kisumu strain. Concentration of the insecticides on the netting materials was examined using the gas chromatography method. Mosquitoes were identified to species level using PCR and genotyped for the kdr gene mutation frequencies. Results WHO bioassays results showed that populations from five sites were highly resistant to the pyrethroids (mortalities ranged from 52.5 to 75.3 %), and two sites were moderately resistant to these insecticides (80.4 – 87.2 %). Homozygote kdr mutations of L1014S ranged from 73 to 88 % in An. gambiae s.s. dominant populations whereas L1014S mutation frequencies were relatively low (7–31 %) in An. arabiensis dominant populations. There was a significant decrease (P < 0.05) in mosquito mortality with time after the spray with both lambda-cyhalothrin (75 % mortality after six months) and with the age of LLINs (60 % mortality after 24 month). Field collected mosquitoes were able to survive exposure to both IRS and LLINs even with newly sprayed walls (86.6–93.5 % mortality) and new LLINs (77.5–85.0 % mortality), Wild mosquitoes collected from the field had significantly lower mortality rates to LLINs (59.6–85.0 %) than laboratory reared susceptible strain (100 %). Insecticide concentration decreased significantly from 0.14 μg/ml in the new nets to 0.077 μg/ml in nets older than 18 months (P < 0.05). Conclusion This study confirms that insecticide decay and developing levels of resistance have a negative contribution to reduced efficacy of ITN and IRS in western Kenya. These factors contribute to decreased efficacy of pyrethroid insectides in ongoing malaria control programs. In order to mitigate against the impact of insecticide resistance and decay it is important to follow the WHO policy to provide the residents with new LLINs every three years of use while maintaining a high level of LLINs coverage and usage. There is also need for urgent development and deployment of non-pyrethroid based vector control tools.
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Affiliation(s)
- Christine L Wanjala
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya. .,Departments of Zoological Sciences, Kenyatta University, Nairobi, Kenya. .,Department of Medical Laboratory Sciences, Masinde Muliro University of Science and Technology, Kakamega, Kenya.
| | - Guofa Zhou
- Program in Public Health, University of California, Irvine, CA, 92697, USA.
| | - Jernard Mbugi
- Departments of Zoological Sciences, Kenyatta University, Nairobi, Kenya.
| | - Jemimah Simbauni
- Departments of Zoological Sciences, Kenyatta University, Nairobi, Kenya.
| | - Yaw A Afrane
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.
| | - Ednah Ototo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya. .,Departments of Zoological Sciences, Kenyatta University, Nairobi, Kenya.
| | - Maxwell Gesuge
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.
| | - Harrysone Atieli
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.
| | - Andrew K Githeko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, CA, 92697, USA.
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Krishnan R, Kumar V, Ananth V, Singh S, Nair AS, Dhar PK. Computational identification of novel microRNAs and their targets in the malarial vector, Anopheles stephensi. SYSTEMS AND SYNTHETIC BIOLOGY 2015; 9:11-7. [PMID: 25972985 DOI: 10.1007/s11693-014-9159-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/10/2014] [Accepted: 12/15/2014] [Indexed: 11/28/2022]
Abstract
MicroRNAs are a ~22 nucleotide small non-coding RNAs found in animals, plants and viruses. They regulate key cellular processes by enhancing, degrading or silencing protein coding targets. Currently most of the data on miRNA is available from Drosophila . Given their important post-transcriptional role in several organisms, there is a need to understand the miRNA mediated processes in normal and abnormal conditions. Here we report four novel microRNAs ast - mir - 2502, ast - mir - 2559, ast - mir - 3868 and ast - mir - 9891 in Anopheles stephensi identified from a set of 3,052 transcriptome sequences, showing average minimum free energy of -31.8 kcal/mol of duplex formation with mRNA indicating their functional relevance. Phylogenetic study shows conservation of sequence signatures within the Class Insecta. Furthermore, 26 potential targets of these four miRNAs have been predicted that play an important role in the mosquito life-cycle. This work leads to novel leads and experimental possibilities for improved understanding of gene regulatory processes in mosquito.
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Affiliation(s)
- Remya Krishnan
- Department of Computational Biology and Bioinformatics, University of Kerala, Trivandrum, Kerala India
| | - Vinod Kumar
- Department of Computational Biology and Bioinformatics, University of Kerala, Trivandrum, Kerala India
| | - Vivek Ananth
- Synthetic Biology Group, Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, U.P. India
| | - Shailja Singh
- Synthetic Biology Group, Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, U.P. India ; Department of Parasitology and Mycology, Institut Pasteur, Paris, France
| | - Achuthsankar S Nair
- Department of Computational Biology and Bioinformatics, University of Kerala, Trivandrum, Kerala India
| | - Pawan K Dhar
- Department of Computational Biology and Bioinformatics, University of Kerala, Trivandrum, Kerala India ; Synthetic Biology Group, Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, U.P. India
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Wang W, Lv Y, Fang F, Hong S, Guo Q, Hu S, Zou F, Shi L, Lei Z, Ma K, Zhou D, Zhang D, Sun Y, Ma L, Shen B, Zhu C. Identification of proteins associated with pyrethroid resistance by iTRAQ-based quantitative proteomic analysis in Culex pipiens pallens. Parasit Vectors 2015; 8:95. [PMID: 25880395 PMCID: PMC4337324 DOI: 10.1186/s13071-015-0709-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 01/31/2015] [Indexed: 12/30/2022] Open
Abstract
Background Mosquito control based on chemical insecticides is considered as an important element in the current global strategies for the control of mosquito-borne diseases. Unfortunately, the development of pyrethroid resistance in important vector mosquito species jeopardizes the effectiveness of insecticide-based mosquito control. To date, the mechanisms of pyrethroid resistance are still unclear. Recent advances in proteomic techniques can facilitate to identify pyrethroid resistance-associated proteins at a large-scale for improving our understanding of resistance mechanisms, and more importantly, for seeking some genetic markers used for monitoring and predicting the development of resistance. Methods We performed a quantitative proteomic analysis between a deltamethrin-susceptible strain and a deltamethrin-resistant strain of laboratory population of Culex pipiens pallens using isobaric tags for relative and absolute quantitation (iTRAQ) analysis. Gene Ontology (GO) analysis was used to find the relative processes that these differentially expressed proteins were involved in. One differentially expressed protein was chosen to confirm by Western blot in the laboratory and field populations of Cx. pipiens pallens. Results We identified 30 differentially expressed proteins assigned into 10 different categories, including oxidoreductase activity, transporter activity, catalytic activity, structural constituent of cuticle and hypothetical proteins. GO analysis revealed that 25 proteins were sub-categorized into 35 hierarchically-structured GO classifications. Western blot results showed that CYP6AA9 as one of the up-regulated proteins was confirmed to be overexpressed in the deltamethrin-resistant strains compared with the deltamethrin-susceptible strains both in the laboratory and field populations. Conclusions This is the first study to use modern proteomic tools for identifying pyrethroid resistance-related proteins in Cx. pipiens. The present study brought to light many proteins that were not previously thought to be associated with pyrethroid resistance, which further expands our understanding of pyrethroid resistance mechanisms. CYP6AA9 was overexpressed in the deltamethrin-resistant strains, indicating that CYP6AA9 may be involved in pyrethroid resistance and may be used as a potential genetic marker to monitor and predict the pyrethroid resistance level of field populations. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-0709-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Weijie Wang
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Department of Pathogen Biology, Hebei Medical University, Shijiazhuang, China.
| | - Yuan Lv
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Fujin Fang
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Shanchao Hong
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Qin Guo
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Shengli Hu
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Feifei Zou
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Linna Shi
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Zhentao Lei
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Kai Ma
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Dan Zhou
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Donghui Zhang
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Yan Sun
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Lei Ma
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Bo Shen
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
| | - Changliang Zhu
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China. .,Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing Medical University, Nanjing, China.
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Ochomo E, Bayoh NM, Kamau L, Atieli F, Vulule J, Ouma C, Ombok M, Njagi K, Soti D, Mathenge E, Muthami L, Kinyari T, Subramaniam K, Kleinschmidt I, Donnelly MJ, Mbogo C. Pyrethroid susceptibility of malaria vectors in four Districts of western Kenya. Parasit Vectors 2014; 7:310. [PMID: 24996418 PMCID: PMC4094666 DOI: 10.1186/1756-3305-7-310] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 06/29/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Increasing pyrethroid resistance in malaria vectors has been reported in western Kenya where long lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the mainstays of vector control. To ensure the sustainability of insecticide-based malaria vector control, monitoring programs need to be implemented. This study was designed to investigate the extent and distribution of pyrethroid resistance in 4 Districts of western Kenya (Nyando, Rachuonyo, Bondo and Teso). All four Districts have received LLINs while Nyando and Rachuonyo Districts have had IRS campaigns for 3-5 years using pyrethroids. This study is part of a programme aimed at determining the impact of insecticide resistance on malaria epidemiology. METHODS Three day old adult mosquitoes from larval samples collected in the field, were used for bioassays using the WHO tube bioassay, and mortality recorded 24 hours post exposure. Resistance level was assigned based on the 2013 WHO guidelines where populations with <90% mortality were considered resistant. Once exposed, samples were identified to species using PCR. RESULTS An. arabiensis comprised at least 94% of all An. gambiae s.l. in Bondo, Rachuonyo and Nyando. Teso was a marked contrast case with 77% of all samples being An. gambiae s.s. Mortality to insecticides varied widely between clusters even in one District with mortality to deltamethrin ranging from 45-100%, while to permethrin the range was 30-100%. Mortality to deltamethrin in Teso District was < 90% in 4 of 6 clusters tested in An arabiensis and <90% in An. gambiae s.s in 5 of 6 clusters tested. To permethrin, mortality ranged between 5.9-95%, with <90% mortality in 9 of 13 and 8 of 13 in An. arabiensis and An. gambiae s.s. respectively. Cluster specific mortality of An. arabiensis between permethin and deltamethrin were not correlated (Z = 2.9505, P = 0.2483). CONCLUSION High levels of pyrethroid resistance were observed in western Kenya. This resistance does not seem to be associated with either species or location. Insecticide resistance can vary within small geographical areas and such heterogeneity may make it possible to evaluate the impact of resistance on malaria and mosquito parameters within similar eco-epidemiological zones.
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Affiliation(s)
- Eric Ochomo
- School of Public Health and Community Development, Maseno University, Maseno, Kenya.
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