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Marcombe S, Doeurk B, Thammavong P, Veseli T, Heafield C, Mills MA, Kako S, Prado MF, Thomson S, Millett S, Hill T, Kentsley I, Davies S, Pathiraja G, Daniels B, Browne L, Nyamukanga M, Harvey J, Rubinstein L, Townsend C, Allen Z, Davey-Spence C, Hupi A, Jones AK, Boyer S. Metabolic Resistance and Not Voltage-Gated Sodium Channel Gene Mutation Is Associated with Pyrethroid Resistance of Aedes albopictus (Skuse, 1894) from Cambodia. INSECTS 2024; 15:358. [PMID: 38786914 PMCID: PMC11122440 DOI: 10.3390/insects15050358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/08/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024]
Abstract
(1) Background: In Cambodia, Aedes albopictus is an important vector of the dengue virus. Vector control using insecticides is a major strategy implemented in managing mosquito-borne diseases. Resistance, however, threatens to undermine the use of insecticides. In this study, we present the levels of insecticide resistance of Ae. albopictus in Cambodia and the mechanisms involved. (2) Methods: Two Ae. albopictus populations were collected from the capital, Phnom Penh city, and from rural Pailin province. Adults were tested with diagnostic doses of malathion (0.8%), deltamethrin (0.03%), permethrin (0.25%), and DDT (4%) using WHO tube assays. Synergist assays using piperonyl butoxide (PBO) were implemented before the pyrethroid assays to detect the potential involvement of metabolic resistance mechanisms. Adult female mosquitoes collected from Phnom Penh and Pailin were tested for voltage-gated sodium channel (VGSC) kdr (knockdown resistance) mutations commonly found in Aedes sp.-resistant populations throughout Asia (S989P, V1016G, and F1534C), as well as for other mutations (V410L, L982W, A1007G, I1011M, T1520I, and D1763Y). (3) Results: The two populations showed resistance against all the insecticides tested (<90% mortality). The use of PBO (an inhibitor of P450s) strongly restored the efficacy of deltamethrin and permethrin against the two resistant populations. Sequences of regions of the vgsc gene showed a lack of kdr mutations known to be associated with pyrethroid resistance. However, four novel non-synonymous mutations (L412P/S, C983S, Q1554STOP, and R1718L) and twenty-nine synonymous mutations were detected. It remains to be determined whether these mutations contribute to pyrethroid resistance. (4) Conclusions: Pyrethroid resistance is occurring in two Ae. albopictus populations originating from urban and rural areas of Cambodia. The resistance is likely due to metabolic resistance specifically involving P450s monooxygenases. The levels of resistance against different insecticide classes are a cause for concern in Cambodia. Alternative tools and insecticides for controlling dengue vectors should be used to minimize disease prevalence in the country.
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Affiliation(s)
- Sébastien Marcombe
- Medical Entomology and Vector-borne Diseases Laboratory, Institut Pasteur du Laos, Ministry of Health, Vientiane P.O. Box 3560, Laos; (S.M.); (P.T.)
- Vector Control Consulting—South East Asia Sole Co., Ltd., Vientiane P.O. Box 3463, Laos
| | - Bros Doeurk
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge, 5 Boulevard Monivong, Phnom Penh P.O. Box 983, Cambodia; (B.D.); (S.B.)
| | - Phoutmany Thammavong
- Medical Entomology and Vector-borne Diseases Laboratory, Institut Pasteur du Laos, Ministry of Health, Vientiane P.O. Box 3560, Laos; (S.M.); (P.T.)
| | - Tuba Veseli
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Derby DE65 5NX, UK
| | - Christian Heafield
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Oxford OX14 2RN, UK
| | - Molly-Ann Mills
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- UK Health Security Agency, Porton Down, Salisbury SP4 0JG, UK
| | - Sedra Kako
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Marcelly Ferreira Prado
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Oxford University Hospitals, Churchill Hospital, Genetics Laboratories, Old Rd, Headington, Oxford OX3 7LE, UK
| | - Shakira Thomson
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Burnham-On-Sea TA8 1AZ, UK
| | - Saffron Millett
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Timothy Hill
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Imogen Kentsley
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Brighton BN8 4HR, UK
| | - Shereena Davies
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Shrewsbury SY1 4YP, UK
| | - Geethika Pathiraja
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Wallingford OX10 7EA, UK
| | - Ben Daniels
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Syngenta, Jealott’s Hill International Research Centre, Bracknell RG42 6EY, Berkshire, UK
| | - Lucianna Browne
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Reading RG31 4SE, UK
| | - Miranda Nyamukanga
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Wythenshawe Hospital, Southmoor Rd, Wythenshawe M23 9LT, Manchester, UK
| | - Jess Harvey
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Oxford Nanopore Technologies plc, Unit 3, Genesis Building, Library Avenue, Harwell, Didcot OX11 0SG, Oxfordshire, UK
| | - Lyranne Rubinstein
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, 69009 Lyon, France
| | - Chloe Townsend
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Zack Allen
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Christopher Davey-Spence
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Adina Hupi
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Oxford OX3 8HP, UK
| | - Andrew K. Jones
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Sebastien Boyer
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge, 5 Boulevard Monivong, Phnom Penh P.O. Box 983, Cambodia; (B.D.); (S.B.)
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Wan-Norafikah O, Aliah-Diyanah S, Atiqah-Izzah Z, Chen CD, Sofian-Azirun M, Lailatul-Nadhirah A, Ibahim MJ. Assessing the bioefficacy of a commercial temephos formulation (Temebate®) for controlling Aedes albopictus larvae in different land use localities in Malaysia. Exp Parasitol 2023; 254:108627. [PMID: 37802180 DOI: 10.1016/j.exppara.2023.108627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/28/2023] [Accepted: 09/25/2023] [Indexed: 10/08/2023]
Abstract
Temephos is the World Health Organization (WHO) recommended larvicide and is still being utilized worldwide to control larvae of dengue vectors; Aedes aegypti and Aedes albopictus. The efficacy of a commercial temephos product; Temebate® to exterminate the local populations of Ae. albopictus larvae originated from different land use particularly dengue-risk and dengue-free housing localities as well as agrarian localities including oil palm plantations, rubber estates and paddy fields was assessed to verify its bioefficacy in these localities. Field populations of Ae. albopictus larvae were attained via a larval survey at each study locality. Each Ae. albopictus larval population was subjected to a 24-h larval bioassay using Temebate® at operational dosage of 1 mg/L. Almost all Ae. albopictus larval populations demonstrated mortalities between 7.00% and 100.00% by the end of the first 4 h of Temebate® exposure with the resistance ratios between 0.94 and 8.33. After 24 h of Temebate® exposure, all sixteen Ae. albopictus larval populations exhibited increased mortalities with ten of them showing 100% mortalities. These results confirmed the relevance of Temebate® to be continuously used by the residents of these localities as their control efforts against dengue vectors. Nevertheless, Temebate® application by consumers in dengue-risk localities need to be carefully monitored to prevent further development of temephos resistance among Ae. albopictus populations and substantiated with other vector control approaches.
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Affiliation(s)
- Othman Wan-Norafikah
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Selangor Branch, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia; HW ReNeU, Universiti Teknologi MARA (UiTM), 40450, Shah Alam, Selangor, Malaysia; Institute of Medical Molecular Biotechnology (IMMB), Faculty of Medicine, Universiti Teknologi MARA (UiTM), Selangor Branch, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia.
| | - Sharifah Aliah-Diyanah
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Selangor Branch, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia
| | - Zaifol Atiqah-Izzah
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Selangor Branch, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia
| | - Chee Dhang Chen
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Mohd Sofian-Azirun
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Asri Lailatul-Nadhirah
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Selangor Branch, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia
| | - Mohammad Johari Ibahim
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Selangor Branch, Sungai Buloh Campus, Jalan Hospital, 47000, Sungai Buloh, Selangor, Malaysia; HW ReNeU, Universiti Teknologi MARA (UiTM), 40450, Shah Alam, Selangor, Malaysia
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Wan-Norafikah O, Hasani NAH, Nabila AB, Najibah I, Nurjuani AHH, Masliana M, Aliah-Diyanah S, Alia-Yasmin Z, Yasmin-Zafirah I, Farah-Farhani A, Azahari AH, Faiqah-Nadhirah M, Nurul-Azira MS. Profiling Insecticide Susceptibility of Aedes Albopictus From Hot Springs in Selangor, Malaysia. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2023; 39:183-191. [PMID: 37796735 DOI: 10.2987/23-7125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
The present study establishes insecticide susceptibility profiles of Aedes albopictus adult populations from 4 hot springs in Selangor, Malaysia, against 7 pyrethroids through an adult mosquito susceptibility bioassay. All Ae. albopictus populations were subjected to a 1-h exposure to each pyrethroid following the World Health Organization. The mortalities were recorded at 60 min of exposure to bifenthrin, 30 min for other pyrethroids, and 24 h posttreatment for all pyrethroids. Complete mortalities were observed upon exposures to the pyrethroids under 60 min and at 24 h posttreatment, excluding permethrin 0.25%, alpha-cypermethrin 0.05%, and bifenthrin 0.2%. These findings indicated that permethrin, deltamethrin, lambda-cyhalothrin, cyfluthrin, and etofenprox possess the recommended pyrethroid adulticide active ingredients that could be applied in vector control programs at these hot springs in the future. Nevertheless, the application of pyrethroids should be carefully monitored in rotation with other insecticide classes, including organophosphates and carbamates to avoid the development of insecticide resistance among mosquito vectors towards all insecticides. Although there were no reported cases of Aedes-borne pathogens at these hot springs to date, the current study results could still assist the Malaysian health authorities in determining approaches to control Aedes populations in these hot springs, if required in the future.
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Asgarian TS, Vatandoost H, Hanafi-Bojd AA, Nikpoor F. Worldwide Status of Insecticide Resistance of Aedes aegypti and Ae. albopictus, Vectors of Arboviruses of Chikungunya, Dengue, Zika and Yellow Fever. J Arthropod Borne Dis 2023; 17:1-27. [PMID: 37609563 PMCID: PMC10440498 DOI: 10.18502/jad.v17i1.13198] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 12/24/2022] [Indexed: 08/24/2023] Open
Abstract
Background Controlling of Aedes aegypti and Ae. albopictus, vectors of five important mosquito-borne diseases, is known as the most effective method to prevent the transmission of arboviruses to humans, but the emergence of insecticide resistance is threat for control and prevention of vector borne diseases. A better understanding of mosquito resistance to insecticides will help to develop more effective methods to control insecticide resistance in mosquito vectors. Methods Worldwide geographical distribution of insecticide resistance in Ae. aegypti and Ae. albopictus by the available papers and map of the data for carbamates, organochlorines, organophosphates, pyrethroids, microbial and insect growth regulator insecticides were reviewed. Article data published up to December 2022 were investigated by searching the following databases: "Google Scholar", "PubMed", "Scopus", "SID" and "Web of Knowledge". Results The results showed that the susceptibility and resistance status of Ae. aegypti and Ae. albopictus to insecticides in the world is very diverse. Conclusion Due to the importance of Ae. aegypti and Ae. albopictus in the transmission of mosquito-borne arboviruses, resistance management should be given more attention worldwide to prevent insecticide resistance in the arbovirus vector and replace the new approach for vector control.
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Affiliation(s)
- Tahereh Sadat Asgarian
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hassan Vatandoost
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
- Department of Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Ali Hanafi-Bojd
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
- Department of Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Nikpoor
- Department of Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
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Low Transmission of Chikungunya Virus by Aedes aegypti from Vientiane Capital, Lao PDR. Pathogens 2022; 12:pathogens12010031. [PMID: 36678379 PMCID: PMC9860973 DOI: 10.3390/pathogens12010031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/05/2022] [Accepted: 12/13/2022] [Indexed: 12/28/2022] Open
Abstract
In 2012−2013, chikungunya virus (CHIKV) was the cause of a major outbreak in the southern part of Lao People’s Democratic Republic (Lao PDR). Since then, only a few imported cases, with isolates belonging to different lineages, were recorded between 2014 and 2020 in Vientiane capital and few autochthonous cases of ECSA-IOL lineage were detected in the south of the country in 2020. The CHIKV epidemiological profile contrasts with the continuous and intensive circulation of dengue virus in the country, especially in Vientiane capital. The study’s aim was to investigate the ability of the local field-derived Aedes aegypti population from Vientiane capital to transmit the Asian and ECSA-IOL lineages of CHIKV. Our results revealed that, for both CHIKV lineages, infection rates were low and dissemination rates were high. The transmission rates and efficiencies evidenced a low vector competence for the CHIKV tested. Although this population of Ae. aegypti showed a relatively modest vector competence for these two CHIKV lineages, several other factors could influence arbovirus emergence such as the longevity and density of female mosquitoes. Due to the active circulation of CHIKV in Southeast Asia, investigations on these factors should be done to prevent the risk of CHIKV emergence and spread in Lao PDR and neighboring countries.
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Marcombe S, Shimell K, Savage R, Howlett E, Luangamath P, Nilaxay S, Vungkyly V, Baby A, King M, Clarke J, Jeffries C, Jojo J, Lacey E, Bhatty F, Mabika D, Dela Cruz A, Fisher C, Mbadu M, Despiniadis I, Brey PT, Thammavong P, Jones AK. Detection of pyrethroid resistance mutations and intron variants in the voltage-gated sodium channel of Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus mosquitoes from Lao People's Democratic Republic. MEDICAL AND VETERINARY ENTOMOLOGY 2022; 36:424-434. [PMID: 35593512 PMCID: PMC9790263 DOI: 10.1111/mve.12580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 05/03/2022] [Indexed: 06/01/2023]
Abstract
In Lao People's Democratic Republic, Aedes aegypti (Linnaeus 1762) and Aedes albopictus (Skuse 1894) mosquitoes (Diptera: Culicidae) are vectors of arboviral diseases such as dengue. As the treatment for these diseases is limited, control of the vectors with the use of pyrethroid insecticides is still essential. However, mutations in the voltage-gated sodium channel (vgsc) gene giving rise to pyrethroid resistance are threatening vector control programs. Here, we analysed both Ae. aegypti and Ae. albopictus mosquitoes, which were collected in different districts of Laos (Kaysone Phomvihane, Vangvieng, Saysettha and Xaythany), for vgsc mutations commonly found throughout Asia (S989P, V1016G and F1534C). Sequences of the vgsc gene showed that the F1534C mutation was prevalent in both Aedes species. S989P and V1016G mutations were detected in Ae. aegypti from each site and were always found together. In addition, the mutation T1520I was seen in Ae. albopictus mosquitoes from Saysettha district as well as in all Ae. aegypti samples. Thus, mutations in the vgsc gene of Ae. aegypti are prevalent in the four districts studied indicating growing insecticide resistance throughout Laos. Constant monitoring programmes and alternative strategies for controlling Aedes should be utilized in order to prolong the effectiveness of pyrethroids thereby maximizing vector control.
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Affiliation(s)
- Sebastien Marcombe
- Institut Pasteur du LaosMinistry of HealthVientianeLao People's Democratic Republic
| | - Katherine Shimell
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Rachel Savage
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Edward Howlett
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | | | - Somphat Nilaxay
- Institut Pasteur du LaosMinistry of HealthVientianeLao People's Democratic Republic
| | - Vacky Vungkyly
- Institut Pasteur du LaosMinistry of HealthVientianeLao People's Democratic Republic
| | - Anne Baby
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Mathew King
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Josie Clarke
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Chloe Jeffries
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Josna Jojo
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Emily Lacey
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Farris Bhatty
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Dadirayi Mabika
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Andrea Dela Cruz
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Cerys Fisher
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Milca Mbadu
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Iasonas Despiniadis
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
| | - Paul T. Brey
- Institut Pasteur du LaosMinistry of HealthVientianeLao People's Democratic Republic
| | - Phoutmany Thammavong
- Institut Pasteur du LaosMinistry of HealthVientianeLao People's Democratic Republic
| | - Andrew K. Jones
- Department of Biological and Medical SciencesOxford Brookes University, HeadingtonOxfordUK
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7
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Updating the Insecticide Resistance Status of Aedes aegypti and Aedes albopictus in Asia: A Systematic Review and Meta-Analysis. Trop Med Infect Dis 2022; 7:tropicalmed7100306. [PMID: 36288047 PMCID: PMC9607256 DOI: 10.3390/tropicalmed7100306] [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: 08/26/2022] [Revised: 09/21/2022] [Accepted: 10/13/2022] [Indexed: 11/24/2022] Open
Abstract
Background: Aedes aegypti and Aedes albopictus are two important vectors of several important arboviruses, including the dengue, chikungunya, and Zika viruses. Insecticide application is an important approach to reduce vector abundance during Aedes spp.-borne outbreaks in the absence of effective vaccines and treatments. However, insecticide overuse can result in the development of resistance, and careful monitoring of resistance markers is required. Methods: This meta-analysis and systematic review explored the spatial and temporal patterns of insecticide resistance in Asia from 2000 to 2021. PubMed, Scopus, EbscoHost, and Embase were used to enhance the search capability. The random-effects model was applied for the 94 studies that met our inclusion criteria for qualitative synthesis and meta-analysis. Results: Four major insecticides were studied (malathion, dichlorodiphenyltrichloroethane, permethrin, and deltamethrin). Dichlorodiphenyltrichloroethane resistance rates were high in both Ae. aegypti and Ae. albopictus (68% and 64%, respectively). Conversely, malathion resistance was less prevalent in Ae. aegypti (3%), and deltamethrin resistance was less common in Ae. albopictus (2%). Ae. aegypti displayed consistently high resistance rates (35%) throughout the study period, whereas the rate of insecticide resistance in Ae. albopictus increased from 5% to 12%. The rates of the major kdr mutations F1534C, V1016G, and S989P were 29%, 26%, and 22%, respectively. Conclusions: Insecticide resistance in both Ae. aegypti and Ae. albopictus is widespread in Asia, although the rates vary by country. Continuous monitoring of the resistance markers and modification of the control strategies will be important for preventing unexpected outbreaks. This systematic review and meta-analysis provided up-to-date information on insecticide resistance in dengue-endemic countries in Asia.
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8
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Calvez E, Bounmany P, Somlor S, Xaybounsou T, Viengphouthong S, Keosenhom S, Brey PT, Lacoste V, Grandadam M. Multiple chikungunya virus introductions in Lao PDR from 2014 to 2020. PLoS One 2022; 17:e0271439. [PMID: 35839218 PMCID: PMC9286254 DOI: 10.1371/journal.pone.0271439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 06/30/2022] [Indexed: 12/04/2022] Open
Abstract
The first documented chikungunya virus (CHIKV) outbreak in Lao People’s Democratic Republic (Lao PDR) occurred in 2012–2013. Since then, several imported and a few autochthonous cases were identified by the national arbovirus surveillance network. The present study aimed to summarize the main genetic features of the CHIKV strains detected in Lao PDR between 2014 and 2020. Samples from Lao patients presenting symptoms compatible with a CHIKV infection were centralized in Vientiane Capital city for real-time RT-PCR screening. Molecular epidemiology was performed by sequencing the E2-6K-E1 region. From 2014 to 2020, two Asian lineage isolates (e.g. French Polynesia; Indonesia), one ECSA-IOL lineage isolate (e.g. Thailand) and one unclassified (e.g. Myanmar) were imported in Vientiane Capital city. Sequences from the autochthonous cases recorded in the Central and Southern parts of the country between July and September 2020 belonged to the ECSA-IOL lineage and clustered with CHIKV strains recently detected in neighboring countries. These results demonstrate the multiple CHIKV introductions in Lao PDR since 2014 and provide evidence for sporadic and time-limited circulation of CHIKV in the country. Even if the circulation of CHIKV seems to be geographically and temporally limited in Lao PDR, the development of international tourism and trade may cause future outbreaks of CHIKV in the country and at the regional level.
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Affiliation(s)
- Elodie Calvez
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
- * E-mail:
| | - Phaithong Bounmany
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Somphavanh Somlor
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Thonglakhone Xaybounsou
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Souksakhone Viengphouthong
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Sitsana Keosenhom
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Paul T. Brey
- Medical Entomology and Vector-Borne Disease Unit, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Vincent Lacoste
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
| | - Marc Grandadam
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane, Lao People’s Democratic Republic
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9
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Small-scale field assessment against the dengue vector Aedes aegypti using the auto-dissemination approach in an urban area of Vientiane, Lao PDR. PLoS One 2022; 17:e0270987. [PMID: 35776762 PMCID: PMC9249186 DOI: 10.1371/journal.pone.0270987] [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: 10/20/2021] [Accepted: 06/21/2022] [Indexed: 11/19/2022] Open
Abstract
Background In Lao PDR, dengue fever is the most important vector borne disease and vector control remains the principal method to fight against Aedes aegypti the primary transmitter mosquito species. Vector control management programs need new strategies in addition to conventional larviciding and adulticiding interventions in the country. In this study, we examined the In2Care® Mosquito Trap’s efficacy using insecticide auto-dissemination strategy. The insecticide pyriproxyfen, present in powder form inside the trap station, contaminates the body of gravid female mosquitoes visiting the traps and is later on disseminated via the mosquitoes in breeding sites surrounding the traps. We tested the attractiveness of the Traps, their efficacy to reduce the larval and adult abundance, and the impact on emergence rates. Specifically, we tested if the servicing interval of the In2Care® Mosquito Trap could be extended to 12 weeks. Methods Two black plastic ovitrap buckets and two BG® sentinel traps were placed in the premises of the Science campus of Vientiane Capital located in an urban area to measure weekly the larval and adult relative abundance of Aedes mosquitoes from 2017 to 2019. Twenty-five In2Care® Mosquito Traps were evenly distributed in this area and two studies of 12 weeks were implemented during January and April 2018 and, July to October 2018 (dry and rainy season, respectively). Every 2 weeks, water samples from 5 In2Care® Traps were randomly selected and tested at the laboratory with Ae. aegypti larvae to measure the larval and pupal mortality. The relative abundance of Aedes mosquitoes in the BG traps® with the presence of In2Care® Traps in 2018, was compared with the surveillance results obtained in 2017 and 2019 without In2Care® Traps. Every week, water samples from the ovitrap buckets were tested for Emergence Inhibition (EI). Results The In2Care® Traps were very attractive to gravid Ae. aegypti mosquitoes specifically during the rainy seasons with 96% of the traps colonized with larvae/pupae within four weeks. The bioassays showed 100% mortality in the water samples from the traps during the twelve weeks studies showing the good efficacy over time of the pyriproxyfen without additional servicing in the 12 week period. In addition, the larvicide was successfully disseminated into the ovitrap buckets placed in the treated area where 100% of EI during all weeks of intervention was measured. There was no significant effect of the treatment on adult abundance reduction in the treated area, probably due to recolonization of adult mosquitoes surrounding the field experiment. Conclusions The observed potential of the In2Care® Mosquito Trap using the auto-dissemination strategy could lead to the use of this new tool in combination with conventional control methods against Dengue vectors in urban tropical areas. Large scale field trials should be implemented in Lao PDR to prove its efficacy for Public Health programs.
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10
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Calvez E, Bounmany P, Balière C, Somlor S, Viengphouthong S, Xaybounsou T, Keosenhom S, Fangkham K, Brey PT, Caro V, Lacoste V, Grandadam M. Using Background Sequencing Data to Anticipate DENV-1 Circulation in the Lao PDR. Microorganisms 2021; 9:microorganisms9112263. [PMID: 34835389 PMCID: PMC8617722 DOI: 10.3390/microorganisms9112263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/21/2021] [Accepted: 10/25/2021] [Indexed: 11/29/2022] Open
Abstract
Since its first detection in 1979, dengue fever has been considered a major public health issue in the Lao People’s Democratic Republic (PDR). Dengue virus (DENV) serotype 1 was the cause of an epidemic in 2010–2011. Between 2012 and 2020, major outbreaks due successively to DENV-3, DENV-4 and recently DENV-2 have been recorded. However, DENV-1 still co-circulated in the country over this period. Here, we summarize epidemiological and molecular data of DENV-1 between 2016 and 2020 in the Lao PDR. Our data highlight the continuous circulation of DENV-1 in the country at levels ranging from 16% to 22% among serotyping tests. In addition, the phylogenetic analysis has revealed the circulation of DENV-1 genotype I at least since 2008 with a co-circulation of different clusters. Sequence data support independent DENV-1 introductions in the Lao PDR correlated with an active circulation of this serotype at the regional level in Southeast Asia. The maintenance of DENV-1 circulation over the last ten years supports a low level of immunity against this serotype within the Lao population. Thereby, the risk of a DENV-1 epidemic cannot be ruled out in the future, and this emphasizes the importance of maintaining an integrated surveillance approach to prevent major outbreaks.
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Affiliation(s)
- Elodie Calvez
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
- Correspondence:
| | - Phaithong Bounmany
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
| | - Charlotte Balière
- Environment and Infectious Risks Unit, Institut Pasteur, 75015 Paris, France; (C.B.); (V.C.)
| | - Somphavanh Somlor
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
| | - Souksakhone Viengphouthong
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
| | - Thonglakhone Xaybounsou
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
| | - Sitsana Keosenhom
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
| | - Kitphithak Fangkham
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
- Lao Army Institute for Preventive Medicine, Vientiane 01030, Laos
| | - Paul T. Brey
- Medical Entomology and Vector Borne Disease Unit, Institut Pasteur du Laos, Vientiane 01030, Laos;
| | - Valérie Caro
- Environment and Infectious Risks Unit, Institut Pasteur, 75015 Paris, France; (C.B.); (V.C.)
| | - Vincent Lacoste
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
| | - Marc Grandadam
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Laos, Vientiane 01030, Laos; (P.B.); (S.S.); (S.V.); (T.X.); (S.K.); (K.F.); (V.L.); (M.G.)
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11
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Rohaizat Hassan M, Atika Azit N, Mohd Fadzil S, Abd Ghani SR, Ahmad N, Mohammed Nawi A. Insecticide resistance of Dengue vectors in South East Asia: a systematic review. Afr Health Sci 2021; 21:1124-1140. [PMID: 35222575 PMCID: PMC8843301 DOI: 10.4314/ahs.v21i3.21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND The insecticides used widely has led to resistance in the vector and impose a challenge to vector control operation. OBJECTIVES This review aims to analyse the distribution of insecticide resistance of dengue vectors in South East Asia and to describe the mechanism of insecticide resistance. METHODS Literature search for articles published on 2015 to 2019 from PubMed, Scopus and ProQuest was performed. Total of 37 studies included in the final review from the initial 420 studies. RESULTS Pyrethroid resistance was concentrated on the west coast of Peninsular Malaysia and Northern Thailand and scattered at Java Island, Indonesia while organophosphate resistance was seen across the Java Island (Indonesia), West Sumatera and North Peninsular Malaysia. Organochlorine resistance was seen in Sabah, Malaysia and scattered distribution in Nusa Tenggara, Indonesia. V1016G, S989P, F1269C gene mutation in Aedes Aegypti were associated with Pyrethroid resistance in Singapore and Indonesia. In Malaysia, over-expressed with monooxygenase P450 genes (CYP9J27, CYP6CB1, CYP9J26 and CYP9M4) Glutathione S-transferases, carboxylesterases commonly associated with pyrethroids resistance in Aedes Aegypti and CYP612 overexpressed in Aedes Albopictus. The genetic mutation in A302S in Aedes Albopictus was associated with organochlorine resistance in Malaysia. CONCLUSIONS Rotation of insecticide, integration with synergist and routine assessment of resistance profile are recommended strategies in insecticide resistance management.
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12
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Gan SJ, Leong YQ, Bin Barhanuddin MFH, Wong ST, Wong SF, Mak JW, Ahmad RB. Dengue fever and insecticide resistance in Aedes mosquitoes in Southeast Asia: a review. Parasit Vectors 2021; 14:315. [PMID: 34112220 PMCID: PMC8194039 DOI: 10.1186/s13071-021-04785-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 05/11/2021] [Indexed: 12/26/2022] Open
Abstract
Dengue fever is the most important mosquito-borne viral disease in Southeast Asia. Insecticides remain the most effective vector control approach for Aedes mosquitoes. Four main classes of insecticides are widely used for mosquito control: organochlorines, organophosphates, pyrethroids and carbamates. Here, we review the distribution of dengue fever from 2000 to 2020 and its associated mortality in Southeast Asian countries, and we gather evidence on the trend of insecticide resistance and its distribution in these countries since 2000, summarising the mechanisms involved. The prevalence of resistance to these insecticides is increasing in Southeast Asia, and the mechanisms of resistance are reported to be associated with target site mutations, metabolic detoxification, reduced penetration of insecticides via the mosquito cuticle and behavioural changes of mosquitoes. Continuous monitoring of the status of resistance and searching for alternative control measures will be critical for minimising any unpredicted outbreaks and improving public health. This review also provides improved insights into the specific use of insecticides for effective control of mosquitoes in these dengue endemic countries. ![]()
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Affiliation(s)
- Soon Jian Gan
- International Medical University, 57000, Kuala Lumpur, Malaysia
| | - Yong Qi Leong
- International Medical University, 57000, Kuala Lumpur, Malaysia.,Monash University Malaysia, 47500, Subang Jaya, Selangor, Malaysia
| | | | - Siew Tung Wong
- International Medical University, 57000, Kuala Lumpur, Malaysia
| | - Shew Fung Wong
- International Medical University, 57000, Kuala Lumpur, Malaysia. .,Institute for Research, Development and Innovation (IRDI), International Medical University, 57000, Kuala Lumpur, Malaysia.
| | - Joon Wah Mak
- International Medical University, 57000, Kuala Lumpur, Malaysia.,Institute for Research, Development and Innovation (IRDI), International Medical University, 57000, Kuala Lumpur, Malaysia
| | - Rohani Binti Ahmad
- Institute for Medical Research, Jalan Pahang, 50588, Kuala Lumpur, Malaysia
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13
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Voltage-Gated Sodium Channel ( Vgsc) Mutation-Based Pyrethroid Resistance in Aedes aegypti Populations of Three Endemic Dengue Risk Areas of Sri Lanka. BIOMED RESEARCH INTERNATIONAL 2021; 2021:8874092. [PMID: 34124263 PMCID: PMC8166465 DOI: 10.1155/2021/8874092] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 03/24/2021] [Accepted: 05/16/2021] [Indexed: 11/17/2022]
Abstract
Background Pyrethroid insecticides are widely used in many countries for chemical-based control of Ae. aegypti. Regardless of their efficacy, the constant use of insecticides has induced insecticide resistance mechanisms, such as knockdown resistance (kdr) in mosquitoes. Sri Lankan Vector Controlling Entities (VCE) have been using a variety of pyrethroid insecticides as the primary approach for dengue control. However, development of any resistance among the Aedes mosquitoes has been limitedly studied in the country. Therefore, the current study was conducted to evaluate the prevalence of F1534C, V1016G, and S989P mutations among Ae. aegypti mosquito populations in three dengue endemic high-risk regions of Sri Lanka. Methodology. Immature (both pupae and larvae) stages of Ae. aegypti mosquitoes were collected from Colombo, Gampaha, and Kandy districts of Sri Lanka from February 2018 to December 2019. Polymerase Chain Reaction- (PCR-) based assay for molecular genotyping of mutations was performed to identify the prevalence of kdr mutations in collected Ae. aegypti populations, separately. The frequencies of the resistant and susceptible kdr alleles were determined by using the Hardy–Weinberg equilibrium. Results The Ae. aegypti populations from Colombo, Gampaha, and Kandy districts showed 46%, 42%, and 22% of F1534C mutation allele frequencies, along with 15%, 12%, and 6% of V1016G mutation allele frequencies, respectively. The mutation allele frequencies of S989 in Colombo, Gampaha, and Kandy districts were 9.5%, 8.5%, and 4.5%, respectively. The wild-type (PP) genotype remained predominant within all the three districts, whereas the homogenous (QQ) mutation genotype occurred only in minority. The abundance of Q allele frequency in Ae. aegypti mosquitoes was relatively higher for all the three mutations in Colombo. Conclusions The findings clearly indicate that long-term insecticide applications and multiple use of pyrethroids have led to the acquisition of kdr mutations, leading to the development of insecticide resistance among local Ae. aegypti populations, especially in the Colombo and Gampaha districts. Therefore, evaluation of the prevalence levels of these kdr mutations highlights the necessity for shifting towards novel vector control strategies.
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14
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Calvez E, Pommelet V, Somlor S, Pompon J, Viengphouthong S, Bounmany P, Chindavong TA, Xaybounsou T, Prasayasith P, Keosenhom S, Brey PT, Telle O, Choisy M, Marcombe S, Grandadam M. Trends of the Dengue Serotype-4 Circulation with Epidemiological, Phylogenetic, and Entomological Insights in Lao PDR between 2015 and 2019. Pathogens 2020; 9:pathogens9090728. [PMID: 32899416 PMCID: PMC7557816 DOI: 10.3390/pathogens9090728] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/28/2020] [Accepted: 08/30/2020] [Indexed: 12/14/2022] Open
Abstract
Dengue outbreaks have regularly been recorded in Lao People's Democratic Republic (PDR) since the first detection of the disease in 1979. In 2012, an integrated arbovirus surveillance network was set up in Lao PDR and an entomological surveillance has been implemented since 2016 in Vientiane Capital. Here, we report a study combining epidemiological, phylogenetic, and entomological analyzes during the largest DENV-4 epidemic ever recorded in Lao PDR (2015-2019). Strikingly, from 2015 to 2019, we reported the DENV-4 emergence and spread at the country level after two large epidemics predominated by DENV-3 and DENV-1, respectively, in 2012-2013 and 2015. Our data revealed a significant difference in the median age of the patient infected by DENV-4 compared to the other serotypes. Phylogenetic analysis demonstrated the circulation of DENV-4 Genotype I at the country level since at least 2013. The entomological surveillance showed a predominance of Aedesaegypti compared to Aedesalbopictus and high abundance of these vectors in dry and rainy seasons between 2016 and 2019, in Vientiane Capital. Overall, these results emphasized the importance of an integrated approach to evaluate factors, which could impact the circulation and the epidemiological profile of dengue viruses, especially in endemic countries like Lao PDR.
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Affiliation(s)
- Elodie Calvez
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
- Correspondence:
| | - Virginie Pommelet
- Epidemiology Unit, Institut Pasteur du Lao PDR, Vientiane 01030, Laos;
| | - Somphavanh Somlor
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Julien Pompon
- Department of Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857, Singapore;
- MIVEGEC, University of Montpellier, CNRS, IRD, 34394 Montpellier, France
| | - Souksakhone Viengphouthong
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Phaithong Bounmany
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Thep Aksone Chindavong
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Thonglakhone Xaybounsou
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Phoyphaylinh Prasayasith
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Sitsana Keosenhom
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
| | - Paul T. Brey
- Medical Entomology and Vector Borne Disease Unit, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (P.T.B.); (S.M.)
| | - Olivier Telle
- Centre de Sciences Humaines (CHS), Centre National de la Recherche Scientifique (CNRS), Delhi 110001, India;
- Center for Policy Research (CPR), Delhi 110001, India
| | - Marc Choisy
- Nuffield Department of Medicine, University of Oxford, Oxford OX3 7LF, UK;
- Oxford University Clinical Research Unit, Ho Chi Minh City 700000, Vietnam
| | - Sébastien Marcombe
- Medical Entomology and Vector Borne Disease Unit, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (P.T.B.); (S.M.)
| | - Marc Grandadam
- Arbovirus and Emerging Viral Diseases Laboratory, Institut Pasteur du Lao PDR, Vientiane 01030, Laos; (S.S.); (S.V.); (P.B.); (T.A.C.); (T.X.); (P.P.); (S.K.); (M.G.)
- Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France
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Saeung M, Ngoen-Klan R, Thanispong K, Muenworn V, Bangs MJ, Chareonviriyaphap T. Susceptibility of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) to Temephos in Thailand and Surrounding Countries. JOURNAL OF MEDICAL ENTOMOLOGY 2020; 57:1207-1220. [PMID: 32159772 DOI: 10.1093/jme/tjaa035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Indexed: 06/10/2023]
Abstract
Aedes-borne virus disease control relies on insecticides to interrupt transmission. Temephos remains a key chemical for control of immature stage Aedes in Thailand and much of Southeast Asia. However, repeated use of insecticides may result in selection for resistance in vector populations, thus compromising operational intervention. Herein, the phenotypic response to temephos by Aedes aegypti (L.) and Aedes albopictus (Skuse) collected in Thailand and surrounding countries is presented. Data from 345 collection sites are included: 283 from literature review (244 sites with Ae. aegypti, 21 with Ae. albopictus, and 18 having both species sampled), plus 62 locations with Ae. aegypti in Thailand conducted between 2014 and 2018. Susceptibility assays followed WHO guidelines using the recommended discriminating dose of temephos (0.012 mg/liter) against late third to early fourth instar Ae. aegypti. Findings revealed 34 locations with susceptible Ae. aegypti, 13 with suspected resistance, and 15 indicating resistance. Published data between 1999 and 2019 in Thailand found Ae. aegypti resistant in 73 of 206 collection sites, whereas 3 locations from 11 sampled with low-level resistant in Ae. albopictus. From surrounding countries conducting temephos assays (Cambodia, Lao PDR, Myanmar, Malaysia, and Singapore), resistance is present in Ae. aegypti and Ae. albopictus from 27 of 56 and 19 of 28 locations, respectively. Routine insecticide susceptibility monitoring should be an operational requirement in vector control programs. Given the wide distribution and apparent increase in temephos-resistance, alternative larvicidal compounds must be considered if chemical control is to remain a viable vector control strategy.
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Affiliation(s)
- Manop Saeung
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Ratchadawan Ngoen-Klan
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Kanutcharee Thanispong
- Division of Vector Borne Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
| | - Vithee Muenworn
- Department of Entomology and Plant Pathology, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand
| | - Michael J Bangs
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- Public Health & Malaria Control Department, PT Freeport Indonesia/International SOS, Kuala Kencana, Papua, Indonesia
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Lamaningao P, Kanda S, Shimono T, Inthavongsack S, Xaypangna T, Nishiyama T. Aedes mosquito surveillance and the use of a larvicide for vector control in a rural area of the Lao People's Democratic Republic. Trop Med Health 2020; 48:54. [PMID: 32612446 PMCID: PMC7325043 DOI: 10.1186/s41182-020-00242-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 06/16/2020] [Indexed: 11/24/2022] Open
Abstract
Background Refillable water containers are commonly used in rural areas of Lao PDR, and they act as Aedes mosquito breeding sites. Aedes aegypti and Ae. albopictus mosquitos are transmission vectors for the dengue virus, which causes dengue fever. Methods Two isolated rural villages in the central part of Lao PDR were selected as study sites. In the intervention village, domestic water containers were continuously treated with a long-lasting matrix release formulation, containing pyriproxyfen, named SumiLarv®2MR. In the control village, entomological activity was monitored, but no intervention was performed. Baseline data were collected in both villages during the late rainy season (October 2017) then distributed SumiLarv®2MR disks in intervention village. This data was compared with data collected during the intervention periods in the dry season (February 2018), rainy season (July 2018 and 2019), and late rainy season (September 2018) in the region. Results Compared with the baseline data (20.24%), the percentage of water containers infested with Ae. aegypti larvae was significantly decreased in the treated village, especially in the rainy seasons in July 2018 (4.11%; P < 0.001) and July 2019 (2.46%; P < 0.001), while the percentage of water containers infested with Ae. albopictus larvae did not decrease significantly in prevalence. No reduction in the frequency of Aedes species was seen in the control village. The Ae. albopictus liked to breed in small habitats (the median water volume of its habitats was 5 L and 10 L in the control and treated village, respectively, while the equivalent values for Ae. aegypti were 30 L and 50 L, respectively). Conclusion The treatment of refillable water storage containers in a rural village with SumiLarv®2MR disks led to significant reductions in the Ae. aegypti population. However, the Ae. albopictus population did not decrease in either the control or treated village. This discrepancy was due to differences in habitat-seeking behaviors and preferred breeding sites such as types of water, water container, and water volume, then led to the differences in results of mosquito prevalence after SumiLarv®2MR disk treatments. The SumiLarv®2MR disk treatment was proven to be effective against the primary dengue-virus vector mosquitoes, Ae. aegypti.
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Affiliation(s)
- Pheophet Lamaningao
- Department of Hygiene and Public Health, Kansai Medical University, Hirakata, Osaka, Japan.,Regenerative Research Center for Intractable Diseases, Kansai Medical University, Hirakata, Osaka, Japan
| | - Seiji Kanda
- Department of Hygiene and Public Health, Kansai Medical University, Hirakata, Osaka, Japan.,Regenerative Research Center for Intractable Diseases, Kansai Medical University, Hirakata, Osaka, Japan
| | - Takaki Shimono
- Department of Hygiene and Public Health, Kansai Medical University, Hirakata, Osaka, Japan.,Regenerative Research Center for Intractable Diseases, Kansai Medical University, Hirakata, Osaka, Japan
| | - Somchit Inthavongsack
- Station of Malariology, Parasitology, and Entomology, Khammouane Provincial Health Department, Thakhek, Khammouane Province Lao People's Democratic Republic
| | - Thonelakhanh Xaypangna
- Khammouane Provincial Health Department, Thakhek, Khammouane Province Lao People's Democratic Republic
| | - Toshimasa Nishiyama
- Department of Hygiene and Public Health, Kansai Medical University, Hirakata, Osaka, Japan
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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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18
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Distribution of insecticide resistance and mechanisms involved in the arbovirus vector Aedes aegypti in Laos and implication for vector control. PLoS Negl Trop Dis 2019; 13:e0007852. [PMID: 31830027 PMCID: PMC6932826 DOI: 10.1371/journal.pntd.0007852] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 12/26/2019] [Accepted: 10/16/2019] [Indexed: 12/13/2022] Open
Abstract
Background The yellow fever mosquito Aedes aegypti is the major vector of dengue, yellow fever, Zika, and Chikungunya viruses. Worldwide vector control is largely based on insecticide treatments but, unfortunately, vector control programs are facing operational challenges due to mosquitoes becoming resistant to commonly used insecticides. In Southeast Asia, resistance of Ae. aegypti to chemical insecticides has been documented in several countries but no data regarding insecticide resistance has been reported in Laos. To fill this gap, we assessed the insecticide resistance of 11 Ae. aegypti populations to larvicides and adulticides used in public health operations in the country. We also investigated the underlying molecular mechanisms associated with resistance, including target site mutations and detoxification enzymes putatively involved in metabolic resistance. Methods and results Bioassays on adults and larvae collected in five provinces revealed various levels of resistance to organophosphates (malathion and temephos), organochlorine (DDT) and pyrethroids (permethrin and deltamethrin). Synergist bioassays showed a significant increased susceptibility of mosquitoes to insecticides after exposure to detoxification enzyme inhibitors. Biochemical assays confirmed these results by showing significant elevated activities of cytochrome P450 monooxygenases (P450), glutathione S-transferases (GST) and carboxylesterases (CCE) in adults. Two kdr mutations, V1016G and F1534C, were detected by qPCR at low and high frequency, respectively, in all populations tested. A significant negative association between the two kdr mutations was detected. No significant association between kdr mutations frequency (for both 1534C and 1016G) and survival rate to DDT or permethrin (P > 0.05) was detected. Gene Copy Number Variations (CNV) were detected for particular detoxification enzymes. At the population level, the presence of CNV affecting the carboxylesterase CCEAE3A and the two cytochrome P450 CYP6BB2 and CYP6P12 were significantly correlated to insecticide resistance. Conclusions These results suggest that both kdr mutations and metabolic resistance mechanisms are present in Laos but their impact on phenotypic resistance may differ in proportion at the population or individual level. Molecular analyses suggest that CNV affecting CCEAE3A previously associated with temephos resistance is also associated with malathion resistance while CNV affecting CYP6BB2 and CYP6P12 are associated with pyrethroid and possibly DDT resistance. The presence of high levels of insecticide resistance in the main arbovirus vector in Laos is worrying and may have important implications for dengue vector control in the country. Aedes aegypti is the major vector of dengue in Laos and the control of this vector rely mainly on insecticide treatments. Compared to the neighboring countries, where resistance has been detected, there was no data on the distribution, the levels, and the mechanisms involved in the resistance in Laos. Laboratory bioassays showed that resistance to the currently used larvicides (temephos) and adulticides (pyrethroids) was present at different levels and distributed throughout the country. This may have important implications for dengue vector control in Laos. The mechanisms underlying the resistance were determined to be both metabolic and target site mutations (kdr) supporting results found in other countries. Several key detoxification enzyme genes were identified as potential candidates for metabolic resistance. This study provides a baseline on insecticide resistance in Laos and will help the Public Health authorities in designing more adapted vector control strategies.
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