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Paronyan L, Babayan L, Vardanyan H, Manucharyan A, Papapostolou KM, Balaska S, Vontas J, Mavridis K. Molecular monitoring of insecticide resistance in major disease vectors in Armenia. Parasit Vectors 2024; 17:54. [PMID: 38321481 PMCID: PMC10848433 DOI: 10.1186/s13071-024-06139-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 01/13/2024] [Indexed: 02/08/2024] Open
Abstract
BACKGROUND Armenia is considered particularly vulnerable to life-threatening vector-borne diseases (VBDs) including malaria, West Nile virus disease and leishmaniasis. However, information relevant for the control of the vectors of these diseases, such as their insecticide resistance profile, is scarce. The present study was conducted to provide the first evidence on insecticide resistance mechanisms circulating in major mosquito and sand fly populations in Armenia. METHODS Sampling sites were targeted based mainly on previous historical records of VBD occurrences in humans and vertebrate hosts. Initially, molecular species identification on the collected vector samples was performed. Subsequently, molecular diagnostic assays [polymerase chain reaction (PCR), Sanger sequencing, PCR-restriction fragment length polymorphism (RFLP), quantitative PCR (qPCR)] were performed to profile for major insecticide resistance mechanisms, i.e. target site insensitivity in voltage-gated sodium channel (vgsc) associated with pyrethroid resistance, acetylcholinesterase (ace-1) target site mutations linked to organophosphate (OP) and carbamate (CRB) resistance, chitin synthase (chs-1) target site mutations associated with diflubenzuron (DFB) resistance and gene amplification of carboxylesterases (CCEs) associated with resistance to the OP temephos. RESULTS Anopheles mosquitoes were principally represented by Anopheles sacharovi, a well-known malaria vector in Armenia, which showed no signs of resistance mechanisms. Contrarily, the knockdown resistance (kdr) mutations V1016G and L1014F/C in the vgsc gene were detected in the arboviral mosquito vectors Aedes albopictus and Culex pipiens, respectively. The kdr mutation L1014S was also detected in the sand fly, vectors of leishmaniasis, Phlebotomus papatasi and P. tobbi, whereas no mutations were found in the remaining collected sand fly species, P. sergenti, P. perfiliewi and P. caucasicus. CONCLUSIONS This is the first study to report on molecular mechanisms of insecticide resistance circulating in major mosquito and sand fly disease vectors in Armenia and highlights the need for the establishment of systematic resistance monitoring practices for the implementation of evidence-based control applications.
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Affiliation(s)
- Lusine Paronyan
- National Center for Disease Control and Prevention, MOH, Yerevan, Republic of Armenia.
| | - Lilit Babayan
- National Center for Disease Control and Prevention, MOH, Yerevan, Republic of Armenia
| | - Haykuhi Vardanyan
- National Center for Disease Control and Prevention, MOH, Yerevan, Republic of Armenia
| | - Arsen Manucharyan
- National Center for Disease Control and Prevention, MOH, Yerevan, Republic of Armenia
| | - Kyriaki Maria Papapostolou
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 70013, Heraklion, Greece
| | - Sofia Balaska
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 70013, Heraklion, Greece
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 70013, Heraklion, Greece
- Department of Crop Science, Pesticide Science Laboratory, Agricultural University of Athens, 11855, Athens, Greece
| | - Konstantinos Mavridis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 70013, Heraklion, Greece.
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Lee DE, Shin J, Kim YH, Choi KS, Choe H, Lee KP, Lee SH, Kim JH. Inference of selection pressures that drive insecticide resistance in Anopheles and Culex mosquitoes in Korea. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 194:105520. [PMID: 37532334 DOI: 10.1016/j.pestbp.2023.105520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 06/25/2023] [Accepted: 07/05/2023] [Indexed: 08/04/2023]
Abstract
Pyrethroids are primarily used for mosquito control in Korea. However, high frequencies of mutations conferring resistance to not only pyrethroids but also to other insecticides have been found in mosquito populations. This study aimed to examine the hypothesis that insecticides used outside of public health may play a role in selection. Briefly, the resistance mutation frequencies to three insecticide groups (pyrethroids, organophosphates, and cyclodienes) were estimated in two representative groups of mosquito species (Anopheles Hyrcanus Group and Culex pipiens complex). The relationship between these frequencies and the land-use status of the collection sites was investigated through multiple regression analysis. In the Anopheles Hyrcanus Group, the frequencies of both ace1 (organophosphate resistance) and rdl (cyclodiene resistance) mutations were positively correlated with 'proximity to golf course', possibly be due to the insecticides used for turf maintenance. They also showed positive correlations with field area and rice paddy area, respectively, suggesting the role of agricultural insecticides in the selection of these resistance traits. For the Cx. pipiens complex, the kdr (pyrethroid resistance), ace1, and rdl mutations were positively correlated with the residential area, field, and rice paddy, respectively. Therefore, pyrethroids used for public health could serve as a direct source of resistance selection pressure against kdr, whereas non-public health insecticides may pose primary selection pressure against the ace1 and rdl traits. The current findings suggest that the insecticides used in agriculture and the golf industry play a significant role in mosquito selection, despite variations in the extent of indirect selection pressure according to the mosquito groups and insecticide classes.
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Affiliation(s)
- Do Eun Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea
| | - Jeewoo Shin
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul 08826, Republic of Korea
| | - Young Ho Kim
- Department of Entomology, Kyungpook National University, Sangju 37224, Republic of Korea
| | - Kwang Shik Choi
- School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Hyeyeong Choe
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul 08826, Republic of Korea
| | - Kwang Pum Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Si Hyeock Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.
| | - Ju Hyeon Kim
- Department of Tropical Medicine and Parasitology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea.
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Stancu IG, Prioteasa FL, Tiron GV, Cotar AI, Fălcuță E, Porea D, Dinu S, Ceianu CS, Csutak O. Distribution of Insecticide Resistance Genetic Markers in the West Nile Virus Vector Culex pipiens from South-Eastern Romania. INSECTS 2022; 13:1062. [PMID: 36421965 PMCID: PMC9698598 DOI: 10.3390/insects13111062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/31/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
Culex pipiens pipiens and Culex pipiens molestus mosquitoes are the vectors of West Nile virus in south-eastern Romania, an area of intense circulation and human transmission of this virus. The level of insecticide resistance for the mosquito populations in the region has not been previously assessed. Culex pipiens mosquitoes collected between 2018 and 2019 in south-eastern Romania from different habitats were subjected to biotype identification by real-time PCR. Substitutions causing resistance to organophosphates and carbamates (F290V and G119S in acetylcholinesterase 1) and to pyrethroids (L1014F in voltage gated Na+ channel) were screened by PCR or sequencing. Substitutions F290V and G119S were detected at very low frequencies and only in heterozygous state in Culex pipiens molestus biotype specimens collected in urban areas. The molestus biotype population analysed was entirely homozygous for L1014F, and high frequencies of this substitution were also found for pipiens biotype and hybrid mosquitoes collected in urban and in intensive agriculture areas. Reducing the selective pressure by limiting the use of pyrethroid insecticides only for regions where it is absolutely necessary and monitoring L1014F mutation should be taken into consideration when implementing vector control strategies.
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Affiliation(s)
- Ioana Georgeta Stancu
- Department of Genetics, Faculty of Biology, University of Bucharest, 1–3 Aleea Portocalelor, 060101 Bucharest, Romania
- Vector-Borne Infections Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
| | - Florian Liviu Prioteasa
- Medical Entomology Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
| | - Georgiana Victorița Tiron
- Vector-Borne Infections Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
- Department of Microbiology, Faculty of Biology, University of Bucharest, 1–3 Aleea Portocalelor, 060101 Bucharest, Romania
| | - Ani Ioana Cotar
- Vector-Borne Infections Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
| | - Elena Fălcuță
- Medical Entomology Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
| | - Daniela Porea
- Danube Delta National Institute for Research and Development, 165 Babadag, 820112 Tulcea, Romania
| | - Sorin Dinu
- Molecular Epidemiology for Communicable Diseases Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
| | - Cornelia Svetlana Ceianu
- Vector-Borne Infections Laboratory, Cantacuzino National Military Medical Institute for Research and Development, 103 Splaiul Independenței, 050096 Bucharest, Romania
| | - Ortansa Csutak
- Department of Genetics, Faculty of Biology, University of Bucharest, 1–3 Aleea Portocalelor, 060101 Bucharest, Romania
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Yavaşoğlu Sİ, Bursalı F, Şimşek FM. Detection of L1014F knockdown resistance mutation in Culex tritaeniorhynchus populations. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 188:105229. [PMID: 36464331 DOI: 10.1016/j.pestbp.2022.105229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 08/21/2022] [Accepted: 09/08/2022] [Indexed: 06/17/2023]
Abstract
Culex tritaeniorhynchus is a major Japanese encephalitis virus vector distributed in Southeast Asia and surrounding countries. The aim of the present study is to investigate insecticide resistance status among 10 Cx. tritaeniorhynchus populations of the Mediterranean region of Turkey. Bioassay results indicated that all of the populations were resistant or at least possibly resistant to 1,1'-(2,2,2-Trichloroethane-1,1-diyl) bis (4-chlorobenzene) (DDT) (4%), [(dimethoxyphosphorothioyl) sulfanyl] butanedioate, Diethyl (malathion) (5%), and 2-[(Propan-2-yl) oxy] phenyl methylcarbamate (propoxur) (0,1%). Whereas, some of the populations were still susceptible to 3-Phenoxybenzyl (1RS)-cis, trans-3-(2,2-dichlorovinyl)-2,2-dimethyl cyclopropane carboxylate (permethrin) (0,75%) and (S)-Cyano (3-phenoxy phenyl) methyl (1R,3R)-3-(2,2-dibromoethen-1-yl)-2,2-dimethylcyclopropane-1-carboxylate (deltamethrin) (0,05%). Biochemical analysis results showed altered alpha esterase, beta esterase, para-nitrophenyl acetate (PNPA), and glutathione-s-transferase (GST) levels in some populations while all of the populations had increased oxidase levels except for the Yumurtalık population. Additionally, all of the populations had sensitive acetylcholinesterase (AChE) levels similar to the control group except for the Erzin population. Correlation analysis showed a significant correlation between mortality rates for deltamethrin and alpha esterase, beta esterase, PNPA, and GST levels while mortality rates for permethrin were significantly correlated with GST levels. An allele-specific polymerase chain reaction (AS-PCR) detected high L1014F allele frequency in the populations. Overall results indicate the urgent need for monitoring and mapping of insecticide resistance in Cx. tritaeniorhynchus populations of the study area for effective vector control management.
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Affiliation(s)
- Sare İlknur Yavaşoğlu
- Aydın Adnan Menderes University, Arts and Science Faculty, Department of Biology, Aydın, Turkey.
| | - Fatma Bursalı
- Aydın Adnan Menderes University, Arts and Science Faculty, Department of Biology, Aydın, Turkey
| | - Fatih Mehmet Şimşek
- Aydın Adnan Menderes University, Arts and Science Faculty, Department of Biology, Aydın, Turkey
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Gomard Y, Alout H, Lebon C, Latreille A, Benlali A, Mavingui P, Tortosa P, Atyame C. Fitness costs associated with a GABA receptor mutation conferring dieldrin resistance in Aedes albopictus. Heredity (Edinb) 2022; 129:273-280. [PMID: 36220919 PMCID: PMC9614001 DOI: 10.1038/s41437-022-00565-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 09/27/2022] [Accepted: 09/27/2022] [Indexed: 11/08/2022] Open
Abstract
Understanding the dynamics of insecticide resistance genes in mosquito populations is pivotal for a sustainable use of insecticides. Dieldrin resistance in Aedes albopictus is conferred by the alanine to serine substitution (A302S or RdlR allele) in the γ-aminobutyric acid (GABA) receptor encoded by the Rdl gene. On Reunion Island, dieldrin resistance was initially reported in natural Ae. albopictus populations sampled in 2008 despite the ban of dieldrin since 1994. To monitor insecticide resistance in Ae. albopictus on the island and to identify its drivers, we measured (i) the frequency of resistance alleles in 19 distinct natural populations collected between 2016 and 2017, (ii) fitness costs associated with dieldrin resistance in laboratory-controlled experiments, and (iii) the resistance conferred by RdlR to fipronil, an insecticide widely used on the island and reported to cross-react with RdlR. The results show a persistence of RdlR in Ae. albopictus natural populations at low frequencies. Among the measured life history traits, mortality in pre-imaginal stages, adults' survival as well as the proportion of egg-laying females were significantly affected in resistant mosquitoes. Finally, bioassays revealed resistance of RdlR mosquitoes to fipronil, suggesting that the use of fipronil in natura could select for the RdlR allele. This study shows that dieldrin resistance is persistent in natural mosquito populations likely as a result of combined effects between fitness costs associated with RdlR and selection exerted by cross-reacting environmental insecticides such as fipronil.
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Affiliation(s)
- Yann Gomard
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France.
- Université de La Réunion, UMR PVBMT (Peuplements Végétaux et Bioagresseurs en Milieu Tropical), F-97410, Saint-Pierre, île de La Réunion, France.
| | - Haoues Alout
- INRAE, UMR 117 ASTRE, INRAE-CIRAD, F-34598, Montpellier, France
| | - Cyrille Lebon
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France
| | - Anne Latreille
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France
| | - Aude Benlali
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France
| | - Patrick Mavingui
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France
| | - Pablo Tortosa
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France
| | - Célestine Atyame
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249, Université de La Réunion, île de La Réunion, France
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Tene‐Fossog B, Fotso‐Toguem YG, Amvongo‐Adjia N, Ranson H, Wondji CS. Temporal variation of high-level pyrethroid resistance in the major malaria vector Anopheles gambiae s.l. in Yaoundé, Cameroon, is mediated by target-site and metabolic resistance. MEDICAL AND VETERINARY ENTOMOLOGY 2022; 36:247-259. [PMID: 35521949 PMCID: PMC9545389 DOI: 10.1111/mve.12577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
Constant assessment of insecticide resistance levels is mandatory to implement adequate malaria control tools, but little information is available on the annual dynamics of resistance. We, therefore, monitored variations in resistance in Anopheles gambiae s.l. over four seasons during 2 years in two localities of Yaoundé: urban Etoa-Meki and peri-urban Nkolondom. Mosquitoes were collected seasonally at larval stage and reared to adults for insecticide susceptibility tests and molecular analysis of resistance mechanisms. Anopheles coluzzii was found in Etoa-Meki and An. gambiae in Nkolondom. Low mortalities to pyrethroids were observed (permethrin <10%, deltamethrin <21%), and resistance extended to 5× and 10× diagnostic doses, revealing a marked increase compared to previous studies. A seasonal variation in resistance was observed with the highest levels within dry seasons in Etoa-Meki and rainy seasons in Nkolondom. The 1014F kdr allele shows a high frequency (0.9), associated with overexpression of metabolic genes (Cyp6M2, Cyp6P4, Cyp9K1, Cyp6Z1, and Cyp6Z2) varying significantly seasonally. This study reveals an escalation in resistance to pyrethroids in Yaoundé's malaria vectors with seasonal variations. An adequate choice of the implementation period of punctual vector control actions according to the resistance profile will help to potentiate the desired effect and thus improve its efficiency.
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Affiliation(s)
- Billy Tene‐Fossog
- Department of Medical EntomologyCentre for Research in Infectious Diseases (CRID)YaoundéCameroon
| | - Yvan Gaetan Fotso‐Toguem
- Department of Medical EntomologyCentre for Research in Infectious Diseases (CRID)YaoundéCameroon
- Department of Animal Biology and Physiology, Faculty of ScienceUniversity of Yaoundé 1YaoundéCameroon
| | - Nathalie Amvongo‐Adjia
- Department of Medical EntomologyCentre for Research in Infectious Diseases (CRID)YaoundéCameroon
- Medical Research CentreInstitute of Medical Research and Medicinal Plants Studies (IMPM)YaoundéCameroon
| | - Hilary Ranson
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Charles S. Wondji
- Department of Medical EntomologyCentre for Research in Infectious Diseases (CRID)YaoundéCameroon
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
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Lebon C, Alout H, Zafihita S, Dehecq JS, Weill M, Tortosa P, Atyame C. Spatio-Temporal Dynamics of a Dieldrin Resistance Gene in Aedes albopictus and Culex quinquefasciatus Populations From Reunion Island. JOURNAL OF INSECT SCIENCE (ONLINE) 2022; 22:6582327. [PMID: 35526103 PMCID: PMC9079611 DOI: 10.1093/jisesa/ieac023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Indexed: 05/31/2023]
Abstract
The control of mosquito populations using insecticides is increasingly threatened by the spread of resistance mechanisms. Dieldrin resistance, conferred by point mutations in the Rdl gene encoding the γ-aminobutyric acid receptor, has been reported at high prevalence in mosquito populations in response to selective pressures. In this study, we monitored spatio-temporal dynamics of the resistance-conferring RdlR allele in Aedes (Stegomyia) albopictus (Skuse, 1895) and Culex (Culex) quinquefasciatus (Say, 1823) populations from Reunion Island. Specimens of both mosquito species were sampled over a 12-month period in three cities and in sites located at lower (<61 m) and higher (between 503 and 564 m) altitudes. Mosquitoes were genotyped using a molecular test detecting the alanine to serine substitution (A302S) in the Rdl gene. Overall, the RdlR frequencies were higher in Cx. quinquefasciatus than Ae. albopictus. For both mosquito species, the RdlR frequencies were significantly influenced by location and altitude with higher RdlR frequencies in the most urbanized areas and at lower altitudes. This study highlights environmental factors that influence the dynamics of insecticide resistance genes, which is critical for the management of insecticide resistance and the implementation of alternative and efficient vector control strategies.
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Affiliation(s)
- Cyrille Lebon
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249; 2 rue Maxime Rivière, 97490 Sainte Clotilde, Reunion Island, France
| | - Haoues Alout
- UMR 117 ASTRE, INRAE-CIRAD, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France
| | - Stanislas Zafihita
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249; 2 rue Maxime Rivière, 97490 Sainte Clotilde, Reunion Island, France
| | - Jean-Sébastien Dehecq
- Service de lutte anti vectorielle, Agence Régionale de Santé-Océan Indien (ARS-OI), 97743 Saint-Denis Cedex 9, Reunion Island, France
| | - Mylène Weill
- ISEM, Université de Montpellier, CNRS, IRD, EPHE, 34095 Montpellier Cedex 5, France
| | - Pablo Tortosa
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249; 2 rue Maxime Rivière, 97490 Sainte Clotilde, Reunion Island, France
| | - Célestine Atyame
- Université de La Réunion, UMR PIMIT (Processus Infectieux en Milieu Insulaire Tropical) CNRS 9192, INSERM 1187, IRD 249; 2 rue Maxime Rivière, 97490 Sainte Clotilde, Reunion Island, France
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Fotakis EA, Mavridis K, Kampouraki A, Balaska S, Tanti F, Vlachos G, Gewehr S, Mourelatos S, Papadakis A, Kavalou M, Nikolakakis D, Moisaki M, Kampanis N, Loumpounis M, Vontas J. Mosquito population structure, pathogen surveillance and insecticide resistance monitoring in urban regions of Crete, Greece. PLoS Negl Trop Dis 2022; 16:e0010186. [PMID: 35176020 PMCID: PMC8890720 DOI: 10.1371/journal.pntd.0010186] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 03/02/2022] [Accepted: 01/21/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND In Greece vector borne diseases (VBD) and foremost West Nile virus (WNV) pose an important threat to public health and the tourist industry, the primary sector of contribution to the national economy. The island of Crete, is one of Greece's major tourist destinations receiving annually over 5 million tourists making regional VBD control both a public health and economic priority. METHODOLOGY Under the auspices of the Region of Crete, a systematic integrative surveillance network targeting mosquitoes and associated pathogens was established in Crete for the years 2018-2020. Using conventional and molecular diagnostic tools we investigated the mosquito species composition and population dynamics, pathogen infection occurrences in vector populations and in sentinel chickens, and the insecticide resistance status of the major vector species. PRINCIPAL FINDINGS Important disease vectors were recorded across the island including Culex pipiens, Aedes albopictus, and Anopheles superpictus. Over 75% of the sampled specimens were collected in the western prefectures potentially attributed to the local precipitation patterns, with Cx. pipiens being the most dominant species. Although no pathogens (flaviviruses) were detected in the analysed mosquito specimens, chicken blood serum analyses recorded a 1.7% WNV antibody detection rate in the 2018 samples. Notably detection of the first WNV positive chicken preceded human WNV occurrence in the same region by approximately two weeks. The chitin synthase mutation I1043F (associated with high diflubenzuron resistance) was recorded at an 8% allelic frequency in Lasithi prefecture Cx. pipiens mosquitoes (sampled in 2020) for the first time in Greece. Markedly, Cx. pipiens populations in all four prefectures were found harboring the kdr mutations L1014F/C/S (associated with pyrethroid resistance) at a close to fixation rate, with mutation L1014C being the most commonly found allele (≥74% representation). Voltage gated sodium channel analyses in Ae. albopictus revealed the presence of the kdr mutations F1534C and I1532T (associated with putative mild pyrethroid resistance phenotypes) yet absence of V1016G. Allele F1534C was recorded in all prefectures (at an allelic frequency range of 25-46.6%) while I1532T was detected in populations from Chania, Rethymnon and Heraklion (at frequencies below 7.1%). Finally, no kdr mutations were detected in the Anopheles specimens included in the analyses. CONCLUSIONS/SIGNIFICANCE The findings of our study are of major concern for VBD control in Crete, highlighting (i) the necessity for establishing seasonal integrated entomological/pathogen surveillance programs, supporting the design of targeted vector control responses and; ii) the need for establishing appropriate insecticide resistance management programs ensuring the efficacy and sustainable use of DFB and pyrethroid based products in vector control.
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Affiliation(s)
- Emmanouil A. Fotakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - Konstantinos Mavridis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - Anastasia Kampouraki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department of Crop Science, Pesticide Science Laboratory, Agricultural University of Athens, Athens, Greece
| | - Sofia Balaska
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department Biology, University of Crete, Heraklion, Greece
| | - Filianna Tanti
- Department of Crop Science, Pesticide Science Laboratory, Agricultural University of Athens, Athens, Greece
| | - George Vlachos
- EcoDevelopment SA-Integrated Mosquito Control, Thessaloniki, Greece
| | - Sandra Gewehr
- EcoDevelopment SA-Integrated Mosquito Control, Thessaloniki, Greece
| | | | - Antonios Papadakis
- General Directorate of Public Health & Social Care of Region of Crete, Heraklion, Greece
| | - Maria Kavalou
- General Directorate of Public Health & Social Care of Region of Crete, Heraklion, Greece
| | - Dimitrios Nikolakakis
- General Directorate of Public Health & Social Care of Region of Crete, Heraklion, Greece
| | - Maria Moisaki
- General Directorate of Public Health & Social Care of Region of Crete, Heraklion, Greece
| | - Nikolaos Kampanis
- General Directorate of Public Health & Social Care of Region of Crete, Heraklion, Greece
| | - Manolis Loumpounis
- General Directorate of Public Health & Social Care of Region of Crete, Heraklion, Greece
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department of Crop Science, Pesticide Science Laboratory, Agricultural University of Athens, Athens, Greece
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Le Navenant A, Brouchoud C, Capowiez Y, Rault M, Suchail S. How lasting are the effects of pesticides on earwigs? A study based on energy metabolism, body weight and morphometry in two generations of Forficula auricularia from apple orchards. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 758:143604. [PMID: 33246715 DOI: 10.1016/j.scitotenv.2020.143604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 10/30/2020] [Accepted: 10/31/2020] [Indexed: 06/11/2023]
Abstract
Widespread use of pesticides to control pests is the dominant system in conventional apple orchards. To avoid adverse side effects, there is a growing interest in promoting alternative methods including biological control based on the use of natural enemies. The European earwig Forficula auricularia L. (Dermaptera: Forficuidae) is an effective predator in apple orchards. Pesticide pressure has been shown to divert energy resources which could have a negative impact on life history traits. In this study we assessed (i) whether variations in pesticide exposure could differentially impact energy reserves, body weight and morphometric parameters of F. auricularia, and (ii) whether these effects persist into the next generation reared under optimal conditions. Individuals from the first generation were collected in late October from organic, IPM and conventional orchards. The next generation was obtained under a rearing program, in the absence of pesticide exposure. Earwigs collected from conventional orchards exhibited lower values for all morphometric parameters compared to those collected in organic orchards. However, a relaxed period without pesticide exposure (in autumn) appears to have allowed the females to recover their energy reserves to ensure reproduction and maternal care. Glycogen contents were the reserves that were more easily restored. However, probably due to the rearing conditions (food ad libitum), all the earwigs from the second generation exhibited higher body weights and energy reserves than their parents.
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Affiliation(s)
- Adrien Le Navenant
- Univ Avignon, Aix Marseille Univ, CNRS, IRD, IMBE, Pôle Agrosciences, 301 rue Baruch de Spinoza, BP 21239, 84916 Avignon, France
| | - Corinne Brouchoud
- Univ Avignon, Aix Marseille Univ, CNRS, IRD, IMBE, Pôle Agrosciences, 301 rue Baruch de Spinoza, BP 21239, 84916 Avignon, France
| | - Yvan Capowiez
- INRAE, UMR 1114 EMMAH Domaine Saint Paul, 84914 Avignon cedex 09, France
| | - Magali Rault
- Univ Avignon, Aix Marseille Univ, CNRS, IRD, IMBE, Pôle Agrosciences, 301 rue Baruch de Spinoza, BP 21239, 84916 Avignon, France.
| | - Séverine Suchail
- Univ Avignon, Aix Marseille Univ, CNRS, IRD, IMBE, Pôle Agrosciences, 301 rue Baruch de Spinoza, BP 21239, 84916 Avignon, France
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10
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Marcombe S, Thammavong P, Luangamath P, Chonephetsarath S, Phommavanh N, Lakeomany K, Nilaxay S, Rahmani Z, Saverton PJ, Abdullateef OH, Forward J, Jacob AE, Khadam S, Ali W, Boer C, Kakinuma H, Hawkins J, Longstreeth R, Portwood NM, Smee M, Brown N, Kuyucu NC, Lechmere S, Stieger G, Maithaviphet S, Nambanya S, Brey PT, Jones AK. Malaria and Dengue Mosquito Vectors from Lao PDR Show a Lack of the rdl Mutant Allele Responsible for Cyclodiene Insecticide Resistance. JOURNAL OF MEDICAL ENTOMOLOGY 2020; 57:815-823. [PMID: 31807752 DOI: 10.1093/jme/tjz227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Indexed: 06/10/2023]
Abstract
The gamma-aminobutyric acid (GABA) receptor, RDL, plays important roles in neuronal signaling and is the target of highly effective insecticides. A mutation in RDL, commonly A296S, underlies resistance to several insecticides such as cyclodienes. Even though the use of cyclodienes has been banned, the occurrence of mutations substituting A296 is notably high in mosquitoes from several countries. Here, we report a survey investigating the prevalence of the Rdl mutant allele in mosquitoes from Laos, a country where mosquito-borne diseases such as malaria and dengue fever are health concerns. Anopheles and Aedes mosquitoes were collected from 12 provinces in Laos. Adult bioassays on Aedes aegypti (Linnaeus) (Diptera: Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) showed that all the populations tested were susceptible to dieldrin (4%) following WHO protocols. Exon 7 from a total of 791 mosquitoes was sequenced to identify the amino acid encoded for at 296 of RDL. Only one of these mosquitoes, Anopheles maculatus rampae Harbach and Somboon (Diptera: Culicidae) from Attapeu, carried the mutant allele being heterozygous for A296S. We therefore found a general lack of the Rdl mutant allele indicating that mosquitoes from Laos are not exposed to insecticides that act on the GABA receptor compared to mosquitoes in several other countries. Identifying the prevalence of the Rdl mutation may help inform the potential use of alternative insecticides that act on the GABA receptor should there be a need to replace pyrethroids in order to prevent/manage resistance.
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Affiliation(s)
- Sebastien Marcombe
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Phoutmany Thammavong
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Phonesavanh Luangamath
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | | | - Nothasin Phommavanh
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Khaitong Lakeomany
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Somphat Nilaxay
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Zuhal Rahmani
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Penelope J Saverton
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Omobolanle H Abdullateef
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Jordan Forward
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Anna E Jacob
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Safina Khadam
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Wlaa Ali
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Chloé Boer
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Hayato Kakinuma
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Joseph Hawkins
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Rosie Longstreeth
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Natalie M Portwood
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Madeleine Smee
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Natasha Brown
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Nursu C Kuyucu
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Susannah Lechmere
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Gabriela Stieger
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
| | - Santi Maithaviphet
- Center for Malariology, Parasitology and Entomology, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Simone Nambanya
- Center for Malariology, Parasitology and Entomology, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Paul T Brey
- Institut Pasteur du Laos, Department of Entomology, Ministry of Health, Vientiane, Lao PDR
| | - Andrew K Jones
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford, UK
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11
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Detection of diflubenzuron and pyrethroid resistance mutations in Culex pipiens from Muğla, Turkey. Acta Trop 2020; 203:105294. [PMID: 31836282 DOI: 10.1016/j.actatropica.2019.105294] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 11/22/2019] [Accepted: 12/09/2019] [Indexed: 11/22/2022]
Abstract
Chemical insecticides are the main tool for vector control worldwide with pyrethroids and the larvicide diflubenzuron (DFB) used extensively against the primary West Nile virus vector Culex pipiens. In this study we monitored the presence, frequency and geographical distribution of the Chitin synthase 1 gene mutations I1043L, I1043M associated with striking diflubenzuron resistance and the knock down resistance mutation L1014F associated with pyrehtroid resistance, in Cx. pipiens populations from Turkey. DFB resistance mutations I1043L, I1043M were found at high frequencies ranging from 15.7% to 37.5% and 25% to 52.7% in all study sites (first report for the presence of DFB resistant mutations, anywhere outside Italy). The L1014F pyrethroid resistance mutation was also present at relatively high frequencies, ranging from 40% to 50%. The high frequency of both DFB and pyrethroid resistance mutations are possibly associated with the intense use of these insecticides in agricultural and mosquito control applications in the region. Given the limited number of available insecticides for vector control these findings are of major importance for public health in Turkey and neighboring countries.
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12
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Yavaşoglu Sİ, Yaylagül EÖ, Akıner MM, Ülger C, Çağlar SS, Şimşek FM. Current insecticide resistance status in Anopheles sacharovi and Anopheles superpictus populations in former malaria endemic areas of Turkey. Acta Trop 2019; 193:148-157. [PMID: 30742803 DOI: 10.1016/j.actatropica.2019.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 02/04/2019] [Accepted: 02/04/2019] [Indexed: 11/17/2022]
Abstract
Anopheles sacharovi and Anopheles superpictus have a significant public health importance since they are primer and seconder malaria vectors of Turkey, respectively. As a result of intensive insecticide usage in historically malaria endemic regions of Turkey for long years, insecticide resistance problem has occurred inevitably. In this study, we aimed to investigate the involvement of the detoxification enzymes in insecticide resistance in Turkish An. sacharovi and An. superpictus populations in the Mediterranean and South-eastern Anatolia region where have a malaria history in the past. Bioassay results indicated that both An. sacharovi and An. superpictus populations are resistant to DDT, resistant or possible resistant to organophosphates and carbamates and finally mostly susceptible to pyrethroids. Although bioassays results indicated high DDT resistance in all mosquito populations, biochemical assays did not show significantly high GST levels in all strains. Almost all An. sacharovi and An. superpictus populations had an increased α and β esterase activity levels while nearly half of the overall populations had an increased p-NPA esterase than the control group. Elevated levels of MFO frequency have been shown in the majority of the populations. Consequently, our results reveal that biochemical resistance mechanisms may play an important role in insecticide resistance in Turkish An. sacharovi and An. superpictus populations. These results give useful cues to monitor the insecticide resistance before it spreads throughout an entire population, enabling early intervention.
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Affiliation(s)
- Sare İlknur Yavaşoglu
- Faculty of Science and Arts, Department of Biology, Adnan Menderes University, 09010, Aydın, Turkey.
| | - Esra Örenlili Yaylagül
- Faculty of Science and Arts, Department of Biology, Adnan Menderes University, 09010, Aydın, Turkey.
| | - Muhammet Mustafa Akıner
- Faculty of Science and Arts, Department of Biology, Recep Tayyip Erdoğan University, 53100, Rize, Turkey.
| | - Celal Ülger
- Faculty of Science and Arts, Department of Biology, Adnan Menderes University, 09010, Aydın, Turkey.
| | - Selim Sualp Çağlar
- Faculty of Science, Department of Biology, Hacettepe University, 06800, Ankara, Turkey.
| | - Fatih Mehmet Şimşek
- Faculty of Science and Arts, Department of Biology, Adnan Menderes University, 09010, Aydın, Turkey.
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13
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Mavridis K, Fotakis EA, Kioulos I, Mpellou S, Konstantas S, Varela E, Gewehr S, Diamantopoulos V, Vontas J. Detection of West Nile Virus - Lineage 2 in Culex pipiens mosquitoes, associated with disease outbreak in Greece, 2017. Acta Trop 2018; 182:64-68. [PMID: 29474832 DOI: 10.1016/j.actatropica.2018.02.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 02/14/2018] [Accepted: 02/17/2018] [Indexed: 11/26/2022]
Abstract
During July-October 2017 a WNV outbreak took place in the Peloponnese, Southern Greece with five confirmed deaths. During routine monitoring survey in the Peloponnese, supported by the local Prefecture, we have confirmed the presence of all three Culex pipiens biotypes in the region, with a high percentage of Culex pipiens/molestus hybrids (37.0%) which are considered a highly competent vector of WNV. Kdr mutations related to pyrethroid resistance were found at relatively low levels (14.3% homozygosity) while no mosquitoes harboring the recently identified chitin synthase diflubenzuron-resistance mutations were detected in the region. As an immediate action, following the disease outbreak (within days), we collected a large number of mosquitoes using CO2 CDC traps from the villages in the Argolis area of the Peloponnese, where high incidence of WNV human infections were reported. WNV lineage 2 was detected in 3 out of 47 Cx. pipiens mosquito pools (detection rate = 6.38%). The virus was not detected in any other mosquito species, such as Aedes albopictus, sampled from the region at the time of the disease outbreak. Our results show that detection of WNV lineage 2 in Cx. pipiens pools is spatially and chronologically associated with human clinical cases, thus implicating Cx. pipiens mosquitoes as the most likely WNV vector. The absence of diflubenzuron resistance mutations and the low frequency of pyrethroid (kdr) resistance mutations indicates the suitability of these insecticides for Cx. pipiens control, in the format of larvicides and/or residual spraying applications respectively, which was indeed the main (evidence based) response, following the disease outbreak.
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14
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Koval WT, Vazquez-Prokopec GM. Environmental stochasticity and intraspecific competition influence the population dynamics of Culex quinquefasciatus (Diptera: Culicidae). Parasit Vectors 2018; 11:114. [PMID: 29482608 PMCID: PMC5828118 DOI: 10.1186/s13071-018-2711-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 02/14/2018] [Indexed: 11/15/2022] Open
Abstract
Background Members of the Culex pipiens complex (Cx. pipiens quinquefasciatus in Southern USA) play a critical role in the spillover of urban arboviruses such as West Nile virus or St. Louis encephalitis virus. Field studies have shown strong correlation between the periodicity of rainfall events and larval proliferation. However, mechanistic determinants driving this relationship are poorly understood. We hypothesize that rainfall events decrease strain from intraspecific competition through the associated reduction of immature density and the introduction of detritus. Results To address our hypothesis, we used laboratory competition experiments to inform a deterministic matrix projection model consisting of an age-structured larval matrix coupled with a stage-structured adult mosquito matrix. Rain events were simulated in a competition-based metabolic age model and compared to a null model including environmental variability. Variable rain delays in two-event simulations showed optimal proliferation occurring with rain delays between 16 and 21 days when including density-dependent effects. Conclusions These results are comparable to the pattern observed in natural populations, indicating that Cx. quinquefasciatus proliferation rates can be modeled mechanistically as a density-dependent system. The empirical understanding of density-dependence as it relates to environmental stochasticity provides a theoretical platform for the study of larval dynamics and the impact of larval control in this medically relevant disease vector. Electronic supplementary material The online version of this article (10.1186/s13071-018-2711-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- William T Koval
- Department of Environmental Sciences, Emory University, Atlanta, GA, 30322, USA
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15
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Analysis of population structure and insecticide resistance in mosquitoes of the genus Culex, Anopheles and Aedes from different environments of Greece with a history of mosquito borne disease transmission. Acta Trop 2017; 174:29-37. [PMID: 28606820 DOI: 10.1016/j.actatropica.2017.06.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 06/01/2017] [Accepted: 06/07/2017] [Indexed: 11/23/2022]
Abstract
Greece has been recently affected by several mosquito borne diseases with the West Nile Virus (WNV) outbreak in 2010 being one of the largest reported in Europe. Currently at the epicenter of an economic and refugee crisis and visited by over 16 million tourists a year the integrated management of diseases transmitted by mosquitoes is a public health and economic priority. Vector control programs rely mainly on insecticides, however data on insecticide resistance and the mosquito fauna is essential for successful applications. We determined the mosquito species composition and population dynamics in areas of increased vulnerability to vector borne disease transmission, as well as investigated the resistance status of major nuisance and disease vectors to insecticides. High mosquito densities were recorded in Thessaloniki and Evros, with Aedes caspius, a nuisance species, Culex pipiens, a known vector of WNV and Anopheles hyrcanus a potential vector of malaria being among the most prevalent species. Both vector species populations reached their peak in late summer. Aedes albopictus was recorded at high densities in Thessaloniki, but not in Evros. Notably, Cx. pipiens hybrids, which show an opportunistic biting behavior and are suspected to be involved in the transmission of the WNV, were recorded in considerable numbers in Thessaloniki and Attica. Culex pipiens and An. hyrcanus, but not Ae. caspius mosquitoes, showed moderate levels of resistance to deltamethrin. The presence of resistance in areas not exposed to vector control indicates that other factors could be selecting for resistance, i.e. pesticide applications for agriculture. Both L1014F and L101C kdr mutations were detected in Cx. pipiens populations. Anopheles hyrcanus resistance was not associated with mutations at the L1014 site. The Ace-1 mutations conferring insensitivity to organophosphates and carbamates were detected at low frequencies in all Cx. pipiens populations. Increased activity of P450s and esterases was found in Cx. pipiens individuals from Thessaloniki. Our study contributes evidence for sustainable and efficient vector control strategies and the prevention of disease outbreaks.
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