Insecticide susceptibility status and resistance mechanism of Anopheles cracens Sallum and Peyton and Anopheles maculatus Theobald (Family: Culicidae) from knowlesi malaria endemic areas in Peninsular Malaysia

Background: Dengue is one of the emerging diseases that can mostly only be controlled by vector control since there is no vaccine for the disease. Although, Dengue has not been reported in Ghana, movement of people from neighbouring countries where the disease has been reported can facilitate transmission of the disease. Objective: This study was carried on the University of Ghana campus to determine the risk of transmission of viral haemorrhagic fevers and the insecticide susceptibility status of Ae. aegypti in some sites in Accra, Ghana. Design: Larval surveys were carried to inspect containers within households and estimate larval indices and adult Aedes mosquitoes were collected using human landing collection technique. WHO tube assays was used to assess the insecticide susceptibility status of Aedes mosquitoes. Results: Ae. aegypti were the most prevalent species, 75.5% and followed by Ae. vittatus, 23.9 %. Ae. albopictus and Ae. granti were in smaller numbers. Household index (HI), Breteau index (BI), and container index were calculated as 8.2%, 11.2% and 10.3% respectively with man-vector contact rate of 0.67 bites/man-hour estimated for the area. The mortalities recorded for Ae. aegypti from WHO tube assays was 88%, 94%, 80% and 99% for DDT (4%), deltamethrin (0.05%), lambdacyhalothrin (0.05%) and permethrin (0.75%) respectively.Conclusion: The survey results indicated that the density of Aedes mosquitoes was considered to be sufficient to promote an outbreak of viral haemorrhagic fevers on Legon Campus. Aedes mosquitoes were found to be resistant to DDT, deltamethrin and lamdacyhalothrin, but susceptible to permethrin. Funding: This study was supported in part by Japan Initiative for Global Research Network on Infectious Diseases(J-Grid).Keywords: Mosquitoes, Aedes aegypti, insecticide, risk, VHF transmission, Ghana

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Species diversity and insecticide resistance within the Anopheles hyrcanus group in Ubon Ratchathani Province, Thailand

Parasites & Vectors ◽

10.1186/s13071-020-04389-4 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Anchana Sumarnrote ◽

Hans J. Overgaard ◽

Vincent Corbel ◽

Kanutcharee Thanispong ◽

Theeraphap Chareonviriyaphap ◽

...

Keyword(s):

Insecticide Resistance ◽

Control Strategies ◽

Resistance Mechanism ◽

Abundant Species ◽

Malaria Vectors ◽

Pcr Assay ◽

Insecticide Susceptibility ◽

Human Landing ◽

Early Peak

Abstract Background Members of the Anopheles hyrcanus group have been incriminated as important malaria vectors. This study aims to identify the species and explore the insecticide susceptibility profile within the Anopheles hyrcanus group in Ubon Ratchathani Province, northeastern Thailand where increasing numbers of malaria cases were reported in 2014. Methods Between 2013 and 2015, five rounds of mosquito collections were conducted using human landing and cattle bait techniques during both the rainy and dry seasons. Anopheles mosquitoes were morphologically identified and their insecticide susceptibility status was investigated. Synergist bioassays were carried out with An. hyrcanus (s.l.) due to their resistance to all insecticides. An ITS2-PCR assay was conducted to identify to species the Hyrcanus group specimens. Results Out of 10,361 Anopheles females collected, representing 18 taxa in 2 subgenera, 71.8% were morphologically identified as belonging to the Hyrcanus Group (subgenus Anopheles), followed by An. barbirostris group (7.9%), An. nivipes (6.5%), An. philippinensis (5.9%) and the other 14 Anopheles species. Specimens of the Hyrcanus Group were more prevalent during the rainy season and were found to be highly zoophilic. Anopheles hyrcanus (s.l.) was active throughout the night, with an early peak of activity between 18:00 h and 21:00 h. ITS2-PCR assay conducted on 603 DNA samples from specimens within the Hyrcanus Group showed the presence of five sisters species. Anopheles peditaeniatus was the most abundant species (90.5%, n = 546), followed by An. nitidus (4.5%, n = 27), An. nigerrimus (4.3%, n = 26), An. argyropus (0.5%, n = 3), and An. sinensis (0.2%, n = 1). All An. hyrcanus (s.l.) specimens that were found resistant to insecticides (deltamethrin 0.05%, permethrin 0.75% and DDT 4% and synergist tests) belonged to An. peditaeniatus. The degree of resistance in An. peditaeniatus to each of these three insecticides was approximately 50%. Addition of PBO (Piperonyl butoxide), but not DEF (S.S.S-tributyl phosphotritioate), seemed to restore susceptibility, indicating a potential role of oxidases as a detoxifying enzyme resistance mechanism. Conclusions A better understanding of mosquito diversity related to host preference, biting activity and insecticide resistance status will facilitate the implementation of locally adapted vector control strategies.

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Insecticide susceptibility status of Aedes aegypti (Diptera: Culicidae) from Townsville

Australian Journal of Entomology ◽

10.1046/j.1440-6055.1999.00071.x ◽

1999 ◽

Vol 38 (1) ◽

pp. 40-43 ◽

Cited By ~ 5

Author(s):

Dv Canyon ◽

Jlk Hii

Keyword(s):

Aedes Aegypti ◽

Insecticide Susceptibility ◽

Susceptibility Status

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Surveys of Arboviruses Vectors in Four Cities Stretching Along a Railway Transect of Burkina Faso: Risk Transmission and Insecticide Susceptibility Status of Potential Vectors

Frontiers in Veterinary Science ◽

10.3389/fvets.2019.00140 ◽

2019 ◽

Vol 6 ◽

Author(s):

Lissy Parfait Eric Ouattara ◽

Ibrahim Sangaré ◽

Moussa Namountougou ◽

Aristide Hien ◽

Ali Ouari ◽

...

Keyword(s):

Burkina Faso ◽

Insecticide Susceptibility ◽

Susceptibility Status

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Draft Genomes of Anopheles cracens and Anopheles maculatus: Comparison of Simian Malaria and Human Malaria Vectors in Peninsular Malaysia

PLoS ONE ◽

10.1371/journal.pone.0157893 ◽

2016 ◽

Vol 11 (6) ◽

pp. e0157893 ◽

Cited By ~ 1

Author(s):

Yee-Ling Lau ◽

Wenn-Chyau Lee ◽

Junhui Chen ◽

Zhen Zhong ◽

Jianbo Jian ◽

...

Keyword(s):

Peninsular Malaysia ◽

Malaria Vectors ◽

Human Malaria ◽

Simian Malaria ◽

Anopheles Cracens

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Aedes albopictus (Skuse) susceptibility status to agrochemical-insecticides used in durian plantating systems in southern Thailand

10.1101/2020.07.09.194746 ◽

2020 ◽

Author(s):

Sakda Ratisupakorn ◽

Sokchan Lorn ◽

Nsa Dada ◽

Aran Ngampongsai ◽

Pawit Chaivisit ◽

...

Keyword(s):

Population Density ◽

Aedes Albopictus ◽

Insect Pests ◽

Field Application ◽

Insecticide Susceptibility ◽

Future Studies ◽

Lambda Cyhalothrin ◽

Southern Thailand ◽

Study Sites ◽

Susceptibility Status

ABSTRACTHigh rates of dengue, chikungunya, and zika morbidity occur in southern Thailand. The intensive application of insecticides in orchards could impact not only agricultural insect pests, but also non-target insects, such as mosquitoes, or non-target beneficial insects. In this study, the population density and insecticide susceptibility of Aedes albopictus populations to field application concentrations of four agrochemical insecticides – cypermethrin, chlorpyrifos, carbaryl, and imidacloprid were examined. Mosquito eggs were collected from durian cultivation sites in five provinces in southern Thailand and hatched and allowed to develop to the adult stage. The study sites were categorized into three groups based on insecticide application; intensive-application of insecticides (IA), less-application of insecticides (LA), and no application of insecticides (NA). Twenty ovitraps were deployed for at least three consecutive days at each study site to collect mosquito eggs and to determine the Ae. albopictus population density then WHO tube assays being used to determine the susceptibility of adult mosquitoes to selected insecticides. This study represents the first report of the agrochemical insecticide susceptibility status of Ae. albopictus collected from durian orchards in southern Thailand. The study found that the populations of Ae. albopictus were susceptible to chlorpyrifos, but showed reduced mortality following exposure to lambda-cyhalothrin, carbaryl, and imidacloprid which is suggestive of the existence of resistance. These findings provide new insights into mosquito insecticide resistance focusing on Ae. albopictus populations and has important implications for mosquito and mosquito-borne disease control in Thailand as well as providing baseline data on which future studies can develop.

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