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Jangir PK, Prasad A. Insecticide susceptibility status on Aedes aegypti (Linn) and Aedes albopictus (Skuse) of Chittorgarh district, Rajasthan, India. Exp Parasitol 2023; 254:108619. [PMID: 37739025 DOI: 10.1016/j.exppara.2023.108619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 08/12/2023] [Accepted: 09/08/2023] [Indexed: 09/24/2023]
Abstract
Vector-borne diseases are a major burden to human health. It accounts for more than 17% of the total infectious diseases and causes more than 0.7 million deaths annually. Mosquitoes are potential vectors for many vector-borne diseases that cause illness to public health, globally. Vector species of the genus Aedes i.e., Aedes aegypti and Aedes albopictus are the vector for many arboviruses such as dengue, chikungunya, yellow fever, and Zika in India. Dengue is one of the most prevalent viral infections causing a high number of cases throughout the world and resistance to insecticides can be a reason for the failure of vector control strategies. This study was carried out to check the degree of resistance among these vectors in the Chittorgarh district of Rajasthan, India through standard World Health Organization protocol. The resistance was monitored to pyrethroids i.e., deltamethrin (0.05%), permethrin (0.75%), alphacypermethrin (0.05%); organochlorine i.e., DDT (4%), and an organophosphate larvicide i.e., temephos (0.02 mg/L) in both vector species. Complete resistance to DDT was observed among all tested populations of both species. All tested populations of Aedes albopictus were found susceptible to pyrethroids. Aedes aegypti was found resistant in the Mangalwad population, unconfirmed resistant in Bhopalsagar and Rashmi populations while the remaining are susceptible to permethrin. The Mangalwad population was also found unconfirmed resistant to deltamethrin and alphacypermethrin. Larvae of both species were found susceptible to temephos. Decreasing the use of DDT will help to reduce the impact on human health and environmental contamination. However, temephos as a larvicide, deltamethrin, and alphacypermethrin as an adulticide can be used in critical disease outbreaks at a minimum concentration as mosquitoes are found susceptible in the study area.
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Affiliation(s)
- Pradeep Kumar Jangir
- Laboratory of Public Health Entomology, Department of Zoology, Mohanlal Sukhadia University, Udaipur, Rajasthan, 313001, India.
| | - Arti Prasad
- Department of Zoology, Mohanlal Sukhadia University, Udaipur, Rajasthan, 313001, India.
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Piedra LA, Rodriguez MM, Lopez I, Ruiz A, Martinez LC, Garcia I, Rey J, Bisset JA. Insecticide Resistance Status of Aedes albopictus (Diptera: Culicidae) Populations from Cuba. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:487-493. [PMID: 36791252 DOI: 10.1093/jme/tjac189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Indexed: 05/13/2023]
Abstract
Aedes albopictus (Skuse, 1894) is one of the major vectors for arboviruses such as dengue, Zika, and chikungunya. Originally from Southeast Asia, this species has spread to Africa, Europe, and the Americas, including Cuba. This spread has been favored by its great adaptability to variable temperatures and to the resistance of its eggs to desiccation. Chemical control of mosquitoes is an essential alternative to stop arbovirus transmission, but insecticide resistance status of the Cuban Ae. albopictus populations is unknown. For this study, Ae. albopictus larvae and adults were collected from two municipalities in Havana, Cuba in 2019. Adult bioassays for deltamethrin, cypermethrin, lambda-cyhalothrin, chlorpyrifos, propoxur, and bendiocarb susceptibility were conducted according to CDC methodology. Larval bioassays for temephos susceptibility were performed following WHO protocols. Resistance profiles for α and β-esterases, glutathione S-transferase (GST), and multifunction oxidases (MFO) pathways were constructed and analyzed. Resistance to temephos and deltamethrin was detected in Mulgoba and Plaza field populations, but resistance to lambda-cyhalothrin was only found in the Plaza colony. Plaza colony exhibited a higher expression level to all four metabolic enzymes and α-esterases and GTS were over-expressed in Mulgoba. The development of insecticide resistance in Cuban Ae. albopictus populations makes it imperative that we develop integrated control strategies to minimize the development of resistance and provide effective vector control that prevents the onset of arbovirus epidemics.
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Affiliation(s)
- Luis Augusto Piedra
- Vector Control Department, Institute of Tropical Medicine "Pedro Kouri", Havana, Cuba
| | | | - Isabel Lopez
- Institute of Materials Science and Technology, University of Havana, Havana, Cuba
| | - Armando Ruiz
- Vector Control Department, Institute of Tropical Medicine "Pedro Kouri", Havana, Cuba
| | - Liss Claudia Martinez
- Vector Control Department, Institute of Tropical Medicine "Pedro Kouri", Havana, Cuba
| | - Israel Garcia
- Vector Control Department, Institute of Tropical Medicine "Pedro Kouri", Havana, Cuba
| | - Jorge Rey
- Florida Medical Entomology Laboratory, University of Florida/IFAS, USA
| | - Juan Andres Bisset
- Vector Control Department, Institute of Tropical Medicine "Pedro Kouri", Havana, Cuba
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Modak MP, Saha D. First report of F1534C kdr mutation in deltamethrin resistant Aedes albopictus from northern part of West Bengal, India. Sci Rep 2022; 12:13653. [PMID: 35953498 PMCID: PMC9372028 DOI: 10.1038/s41598-022-17739-2] [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: 03/09/2022] [Accepted: 07/29/2022] [Indexed: 11/27/2022] Open
Abstract
Dengue is the most rapidly spreading vector-borne disease with an estimated 100–400 million cases each year. Control of Dengue vectors largely depends upon synthetic pyrethroids. Development of insecticide resistance in Aedes mosquitoes however, poses severe threat to insecticide-based vector management programme. Mutations in the Voltage Gated Sodium Channel gene (vgsc) serve as the primary machinery behind this resistance development. In Aedes albopictus, at least four such kdr (knock down resistance) mutations had already been documented. Here, we describe the occurrence of F1534C kdr mutation in wild population of Ae. albopictus from northern part of West Bengal, India including a novel T1520I mutation. Four populations of Ae. albopictus from the studied region were found resistant against DDT and synthetic pyrethroids, among them only one population possessed F1534C kdr mutation. A total of 200 successful amplification followed by partial sequencing of vgsc gene further revealed the presence of F1534C kdr mutation in both phenotypically susceptible and resistant mosquito specimen. Studied populations were found 81% homozygote susceptible (1534F/F), 12.5% heterozygote (1534F/C) and 6% homozygote resistant (1534C/C) for F1534C kdr mutation. The findings of the current study will help to uncover the mechanisms underlying insecticide resistance and hence to reduce errors in vector control measurements.
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Affiliation(s)
- Manas Pratim Modak
- Insect Biochemistry and Molecular Biology Laboratory, Department of Zoology, University of North Bengal, Raja Rammohunpur, Siliguri, District-Darjeeling, West Bengal, 734013, India
| | - Dhiraj Saha
- Insect Biochemistry and Molecular Biology Laboratory, Department of Zoology, University of North Bengal, Raja Rammohunpur, Siliguri, District-Darjeeling, West Bengal, 734013, India.
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Nawaz S, Tahir HM, Asif Mahmood M, Summer M, Ali S, Ali A, Gormani AH. Current Status of Pyrethroids Resistance in Aedes aegypti (Culicidae: Diptera) in Lahore District, Pakistan: A Novel Mechanistic Insight. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:2432-2438. [PMID: 34343301 DOI: 10.1093/jme/tjab137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Indexed: 06/13/2023]
Abstract
Aedes aegypti (Linnaeus, 1762) is a major vector responsible for dengue transmission. Insecticides are being used as the most effective tool to control vector populations in Lahore, Pakistan. Control of Ae. aegypti is threatened by the development of resistance against insecticides. The current status of insecticide resistance was evaluated against pyrethroids (deltamethrin, cypermethrin, and lambda-cyhalothrin) in different populations of Lahore (Model Town, Mishri Shah, Sadar Cantt, Walton, and Valencia). The susceptibility of the larval and adult populations was tested following the standard WHO guidelines. Moderate to high levels of resistance were found against pyrethroids in the larval (RR50: 3.6-27.2 and RR90: 5-90) and adult populations (percentage mortality < 98%). Biochemical assays revealed a statistically significant increase in the enzyme level in all field populations compared to the laboratory strain. The value of esterase was one-fold higher, monooxygenase was 3.9- to 4.7-fold higher, and glutathione S-transferases was 1.9- to 2.6-fold higher in field populations compared to the laboratory strain. These results depict the presence of resistance against deltamethrin, cypermethrin, and lambda-cyhalothrin in field populations of Lahore mediated by metabolic enzymes i.e. esterases, monooxygenases, and glutathione S-transferase.
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Affiliation(s)
- Saira Nawaz
- Department of Zoology, Government College University, Lahore, Pakistan
| | | | | | - Muhammad Summer
- Department of Zoology, Government College University, Lahore, Pakistan
| | - Shaukat Ali
- Department of Zoology, Government College University, Lahore, Pakistan
| | - Aamir Ali
- Department of Zoology, Government College University, Lahore, Pakistan
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Janich AJ, Saavedra-Rodriguez K, Vera-Maloof FZ, Kading RC, Rodríguez AD, Penilla-Navarro P, López-Solis AD, Solis-Santoyo F, Perera R, Black WC. Permethrin Resistance Status and Associated Mechanisms in Aedes albopictus (Diptera: Culicidae) From Chiapas, Mexico. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:739-748. [PMID: 33034352 PMCID: PMC7954096 DOI: 10.1093/jme/tjaa197] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Indexed: 06/11/2023]
Abstract
There are major public health concerns regarding the spread of mosquito-borne diseases such as dengue, Zika, and chikungunya, which are mainly controlled by using insecticides against the vectors, Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse). Pyrethroids are the primary class of insecticides used for vector control, due to their rapid knockdown effect and low toxicity to vertebrates. Unfortunately, continued use of pyrethroids has led to widespread insecticide resistance in Ae. aegypti; however, we lack information for Ae. albopictus-a sympatric species in Chiapas since 2002. In this study, we evaluated the permethrin resistance status of Ae. albopictus collected from Mexico and Texas. We also selected for permethrin resistance in the laboratory and investigated the potential mechanisms conferring resistance in this species. Knockdown resistance mutations, specifically F1534C, in the voltage-gated sodium channel gene, and increased activity of detoxifying enzymes were evaluated. Low levels of permethrin resistance (<2.4-fold) were observed in our field populations of Ae. albopictus and the F1534C mutation was not detected in any of the sites. Low levels of resistance were also observed in the artificially selected strain. There was significantly higher cytochrome P450 activity in our permethrin-selected and nonselected strains from Mexico compared to the control strain. Our results suggest the Ae. albopictus sampled from 2016 are mostly susceptible to pyrethroids. These results contrast with the high levels of permethrin resistance (>58-fold) found in Ae. aegypti from the same sites in Mexico. This research indicates the importance of continued monitoring of Ae. albopictus populations to prevent resistance from developing in the future.
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Affiliation(s)
- Ashley J Janich
- Arthropod Borne Infectious Disease Laboratory, Colorado State University, Fort Collins, CO
| | | | - Farah Z Vera-Maloof
- Arthropod Borne Infectious Disease Laboratory, Colorado State University, Fort Collins, CO
| | - Rebekah C Kading
- Arthropod Borne Infectious Disease Laboratory, Colorado State University, Fort Collins, CO
| | - Américo D Rodríguez
- Centro Regional de Investigación en Salud Pública, Tapachula, Chiapas, Mexico
| | | | - Alma D López-Solis
- Centro Regional de Investigación en Salud Pública, Tapachula, Chiapas, Mexico
| | | | - Rushika Perera
- Arthropod Borne Infectious Disease Laboratory, Colorado State University, Fort Collins, CO
| | - William C Black
- Arthropod Borne Infectious Disease Laboratory, Colorado State University, Fort Collins, CO
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Wan-Norafikah O, Chen CD, Sofian-Azirun M. Organochlorines and organophosphates susceptibility of Aedes albopictus Skuse larvae from agricultural and non-agricultural localities in Peninsular Malaysia. Saudi J Biol Sci 2021; 28:1010-1016. [PMID: 33424394 PMCID: PMC7783822 DOI: 10.1016/j.sjbs.2020.11.040] [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: 09/16/2020] [Revised: 11/05/2020] [Accepted: 11/08/2020] [Indexed: 12/05/2022] Open
Abstract
Aedes albopictus larvae obtained from different types of agricultural and non-agricultural localities in Peninsular Malaysia were subjected to several larvicides at World Health Organization (WHO) recommended dosages. Upon 24 h of WHO larval bioassay using two organochlorines and six organophosphates, high resistance against dichlorodiphenyltrichloroethane (DDT), temephos, chlorpyrifos and bromophos were demonstrated among all larval populations. Aedes albopictus larvae from both paddy growing areas (92.33% mortality) and rubber estates (97.00% mortality) were moderately resistant to dieldrin while only Ae. albopictus larvae from dengue prone residential areas (89.00% mortality) showed high resistance against dieldrin. All Ae. albopictus larval populations also developed either incipient or high resistance to both malathion (33.67%–95.33% mortality) and fenitrothion (73.00%–92.67% mortality). Only Ae. albopictus larvae from fogging-free residential areas that were tolerant to fenthion (97.33% mortality), whereas Ae. albopictus larvae from dengue prone residential areas were highly resistant to the same organophosphate (88.33% mortality). Cross resistance between intraclass and interclass larvicides of organochlorines and organophosphates were also exhibited in this study. The present study provided baseline data on various susceptibility levels of Ae. albopictus larval populations from different types of agricultural and non-agricultural localities against organochlorines and organophosphates at WHO recommended dosages. Nevertheless, further susceptibility investigations are suggested using revised doses of larvicides established from the local reference strain of Ae. albopictus to prevent the underestimation or overestimation of insecticide resistance level among Ae. albopictus field strains of larvae.
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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 Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, 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
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Bharati M, Rai P, Saha D. Insecticide resistance in Aedes albopictus Skuse from sub-Himalayan districts of West Bengal, India. Acta Trop 2019; 192:104-111. [PMID: 30763564 DOI: 10.1016/j.actatropica.2019.02.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/07/2019] [Accepted: 02/09/2019] [Indexed: 10/27/2022]
Abstract
Dengue is one of the most rapidly spreading infectious diseases prevalent throughout the tropical and sub-tropical regions of the world. In absence of specific medications and vaccines, the sole method of disease prevention relies on vector control mainly using insecticides. But with the advent of Insecticide resistance, worldwide vector control programs are facing failure. In this study, eleven different Ae. albopictus population from sub-Himalayan districts of West Bengal, India were investigated as per WHO protocols to find out the current status of insecticide susceptibility against DDT, permethrin and propoxur. Also the role of three insecticide detoxifying enzymes underlying observed resistance was investigated through quantitative and synergistic assays to unveil the mechanism of insecticide resistance. It was found that majority of studied populations were resistant to 4% DDT. Two populations, namely Alipurduar (APD) and Jalpaiguri (JPG) were severely resistant to 0.75% permethrin, whereas only JPG population was found to exhibit severe resistance against 0.1% propoxur. Moreover, the involvement of detoxifying enzymes was also noted in conferring resistance against DDT and Permethrin. This study indicates the inefficacy of DDT in controlling Ae. albopictus populations in the study region. This study may help in implementation of an efficient vector control and insecticide resistance management strategies.
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Bharati M, Saha D. Assessment of insecticide resistance in primary dengue vector, Aedes aegypti (Linn.) from Northern Districts of West Bengal, India. Acta Trop 2018; 187:78-86. [PMID: 30026024 DOI: 10.1016/j.actatropica.2018.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/10/2018] [Accepted: 07/04/2018] [Indexed: 01/01/2023]
Abstract
Aedes mosquitoes are the major vectors transmitting several arboviral diseases such as dengue, zika and chikungunya worldwide. Northern districts of West Bengal is home to several epidemics vectored by mosquito including dengue infections, proper control of which depends on efficient vector control. However the onset of insecticide resistance has resulted in failure of vector control approaches. This study was carried out to unveil the level of insecticide resistance prevailing among the primary dengue vector in this dengue endemic region of India. It was observed that, field caught populations of Ae. aegypti were moderately to severely resistant to majority of the insecticide classes tested, i.e. Organochlorine (DDT), Organophosphates (temephos, malathion), Synthetic Pyrethroids (deltamethrin, lambdacyhalothrin and permethrin) and carbamate (propoxur). In majority of the populations, metabolic detoxification seemed to play the underlying role behind the development of insecticide resistance. This study seems to be the first report revealing the pattern of insecticide resistance in Ae. aegypti from Northern West Bengal. Efficient disease management in this region can only be achieved through proper insecticide resistance management. This study may help the concerned authorities in the formulation of an effective vector control strategy throughout this region incorporating the knowledge gained through this study.
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Bharati M, Saha D. Multiple insecticide resistance mechanisms in primary dengue vector, Aedes aegypti (Linn.) from dengue endemic districts of sub-Himalayan West Bengal, India. PLoS One 2018; 13:e0203207. [PMID: 30199543 PMCID: PMC6130861 DOI: 10.1371/journal.pone.0203207] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 08/16/2018] [Indexed: 12/21/2022] Open
Abstract
Background Mosquitoes belonging to genus Aedes are the prime vectors of several arboviral diseases such as Dengue, Zika and Chikungunya worldwide. Every year numerous cases of dengue infections occur throughout the world, proper control of which depends on efficient vector control. However the onset of insecticide resistance has resulted in failure of vector control approaches. Principal findings This study was carried out to unveil the degree of prevailing insecticide resistance along with its underlying mechanisms among the primary dengue vector in dengue endemic districts of West Bengal, India through standard WHO protocol. It was observed that, the majority of the tested populations were found to possess resistance to more than one insecticide. In adult bioassay, the toxicity levels of the six tested insecticides was found to decrease in the following order: deltamethrin > lambdacyhalothrin > malathion > propoxur > permethrin > DDT. In larval bioassay, one of the tested populations was found to possess moderate resistance against temephos, mortality percentage 92.5% and 79.8% for WHO (0.0200 ppm) and National Vector Borne disease Programme, India recommended dose (0.0125 ppm) respectively. Carboxylesterases were found to be involved in conferring resistance as revealed in synergistic and quantitative assay against temephos in North Dinajpur (NDP) population and malathion in Alipurduar (APD) and Darjeeling (DAR) populations. Similar correlations were also observed in the majority of the tested populations between reduced susceptibilities against pyrethroid insecticides and Cytochrome P450s activity. Conclusion Efficient disease management in this region can only be achieved through proper integrated vector management along with tools to minimize insecticide resistance. This study may help the concerned authorities in the formulation of an effective vector control strategy throughout this region incorporating the knowledge gained through this study.
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Affiliation(s)
- Minu Bharati
- Insect Biochemistry and Molecular Biology Laboratory, Department of Zoology, University of North Bengal, Raja Ramohunpur, P.O. North Bengal University, Siliguri, District – Darjeeling, West Bengal, India
| | - Dhiraj Saha
- Insect Biochemistry and Molecular Biology Laboratory, Department of Zoology, University of North Bengal, Raja Ramohunpur, P.O. North Bengal University, Siliguri, District – Darjeeling, West Bengal, India
- * E-mail: ,
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Chatterjee M, Ballav S, Maji AK, Basu N, Sarkar BC, Saha P. Polymorphisms in voltage-gated sodium channel gene and susceptibility of Aedes albopictus to insecticides in three districts of northern West Bengal, India. PLoS Negl Trop Dis 2018; 12:e0006192. [PMID: 29309419 PMCID: PMC5774824 DOI: 10.1371/journal.pntd.0006192] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/19/2018] [Accepted: 12/26/2017] [Indexed: 11/19/2022] Open
Abstract
Background The control and prevention of dengue largely depends on vector control measures, environmental management, and personal protection. Dengue control programmes are facing great challenges due to development of insecticide resistance among vector mosquitoes. Information on susceptibility status to different insecticides is important for national programmes to formulate vector control strategies. Methods We have studied the larval susceptibility of Aedes albopictus to temephos and adult susceptibility to 4% DDT, 0.05% deltamethrin, and 5% malathion as per WHO protocols in the northern districts of West Bengal. Polymorphisms in the VGSC gene were studied by direct sequencing of PCR products. Results The Ae. albopictus larval population showed sensitive [Resistance Ratio (RR99)<3] to moderate levels of resistance (5<RR99>10) to temephos at different study sites. Adult bioassay results revealed that Ae. albopictus was highly resistant to DDT [Corrected Mortality (CM) < 90%] in all the study sites and susceptible to deltamethrin and malathion (CM > 98%), except in Dhupguri where a low level of resistance to deltamethrin (CM = 96.25%) was recorded. None of the six important kdr mutations (S953P, I975M/V, L978, V980G, F1474C, D1703Y) were found in the VGSC of studied mosquitoes, but we identified 11 synonymous and 1 non-synonymous mutation in the VGSC gene. Conclusion The higher susceptibility level to deltamethrin and malathion, along with the absence of important kdr mutations indicates that these two insecticides are still effective against Ae. albopictus in the study areas. The susceptibility status of temephos should be monitored closely as low to moderate levels of resistance were observed in few sites. A similar study is recommended for monitoring and early detection of insecticide resistance in other parts of the country. Dengue is one of the most important arboviral infections in India, and transmitted by Aedes mosquitoes. Control of dengue largely depends on effective vector control measures as no specific drugs or vaccines are available, to date. The knowledge of insecticide susceptibility status for local vector mosquitoes is essential for the formulation of effective vector control measures. Therefore, regular monitoring of insecticide susceptibility is essential for the early detection of resistance. In the present study, sensitive to moderate levels of resistance to temephos were recorded among the Aedes albopictus larval populations of different study sites. Adult Ae. albopictus were highly resistant to DDT and susceptible to deltamethrin and malathion in all the study sites, except one site where a low level of resistance to deltamethrin was observed. By sequencing the VGSC gene we observed that the studied Ae. albopictus population does not contain any of the important kdr mutations which are associated with DDT and pyrethroid resistance in other insects. We found only one non-synonymous mutation at codon S1485L, but its role in pyrethroid resistance is yet to be established.
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Affiliation(s)
- Moytrey Chatterjee
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Sudeep Ballav
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Ardhendu K. Maji
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Nandita Basu
- Director, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Biplab Chandra Sarkar
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
| | - Pabitra Saha
- Department of Microbiology, Calcutta School of Tropical Medicine, Kolkata, West Bengal, India
- Department of Zoology, A. P. C. Roy Govt. College, Himachal Bihar, Matigara, Siliguri, West Bengal, India
- * E-mail:
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Protection against mosquito vectors Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus using a novel insect repellent, ethyl anthranilate. Acta Trop 2017; 174:56-63. [PMID: 28666890 DOI: 10.1016/j.actatropica.2017.06.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/16/2017] [Accepted: 06/19/2017] [Indexed: 02/06/2023]
Abstract
Growing concern on the application of synthetic mosquito repellents in the recent years has instigated the identification and development of better alternatives to control different mosquito-borne diseases. In view of above, present investigation evaluates the repellent activity of ethyl anthranilate (EA), a non-toxic, FDA approved volatile food additive against three known mosquito vectors namely, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus under laboratory conditions following standard protocols. Three concentration levels (2%, 5% and 10% w/v) of EA were tested against all the three selected mosquito species employing K & D module and arm-in-cage method to determine the effective dose (ED50) and complete protection time (CPT), respectively. The repellent activity of EA was further investigated by modified arm-in-cage method to determine the protection over extended spatial ranges against all mosquito species. All behavioural situations were compared with the well-documented repellent N,N-diethylphenyl acetamide (DEPA) as a positive control. The findings demonstrated that EA exhibited significant repellent activity against all the three mosquitoes species. The ED50 values of EA, against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus were found to be 0.96%, 5.4% and 3.6% w/v, respectively. At the concentration of 10% w/v, it provided CPTs of 60, 60 and 30min, respectively, against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes. Again in spatial repellency evaluation, EA was found to be extremely effective in repelling all the three tested species of mosquitoes. Ethyl anthranilate provided comparable results to standard repellent DEPA during the study. Results have concluded that the currently evaluated chemical, EA has potential repellent activity against some well established mosquito vectors. The study emphasizes that repellent activity of EA could be exploited for developing effective, eco-friendly, acceptable and safer alternative to the existing harmful repellents for personal protection against different hematophagous mosquito species.
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