Rapid evolution of reduced receptivity to interspecific mating in the dengue vector Aedes aegypti in response to satyrization by invasive Aedes albopictus

Background In Malaysia, dengue remains a top priority disease and usage of insecticides is the main method for dengue vector control. Limited baseline insecticide resistance data in dengue hotspots has prompted us to conduct this study. The present study reports the use of a map on the insecticide susceptibility status of Aedes aegypti and Aedes albopictus to provide a quick visualization and overview of the distribution of insecticide resistance. Method and results The insecticide resistance status of Aedes populations collected from 24 dengue hotspot areas from the period of December 2018 until June 2019 was proactively monitored using the World Health Organization standard protocol for adult and larval susceptibility testing was conducted, together with elucidation of the mechanisms involved in observed resistance. For resistance monitoring, susceptibility to three adulticides (permethrin, deltamethrin, and malathion) was tested, as well as susceptibility to the larvicide, temephos. Data showed significant resistance to both deltamethrin and permethrin (pyrethroid insecticides), and to malathion (organophosphate insecticide) in all sampled Aedes aegypti populations, while variable resistance patterns were found in the sampled Aedes albopictus populations. Temephos resistance was observed when larvae were tested using the diagnostic dosage of 0.012mg/L but not at the operational dosage of 1mg/L for both species. Conclusion The present study highlights evidence of a potential threat to the effectiveness of insecticides currently used in dengue vector control, and the urgent requirement for insecticide resistance management to be integrated into the National Dengue Control Program.

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Widespread evidence for interspecific mating between Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in nature

Infection Genetics and Evolution ◽

10.1016/j.meegid.2015.08.016 ◽

2015 ◽

Vol 36 ◽

pp. 456-461 ◽

Cited By ~ 22

Author(s):

I.E. Bargielowski ◽

L.P. Lounibos ◽

D. Shin ◽

C.T. Smartt ◽

M.C. Carrasquilla ◽

...

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Interspecific Mating

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Dengue vector mosquitoes in Japan : The role of Aedes albopictus and Aedes aegypti in the 1942-1944 dengue epidemics of Japanese Main Islands

Medical Entomology and Zoology ◽

10.7601/mez.49.267 ◽

1998 ◽

Vol 49 (4) ◽

pp. 267-274 ◽

Cited By ~ 33

Author(s):

Susumu HOTTA

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Dengue Vector ◽

Dengue Epidemics

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Larvicidal Efficacy of Different Plant Parts of Railway Creeper, Ipomoea cairica Extract Against Dengue Vector Mosquitoes, Aedes albopictus (Diptera: Culicidae) and Aedes aegypti (Diptera: Culicidae)

Journal of Insect Science ◽

10.1093/jisesa/ieu042 ◽

2014 ◽

Vol 14 (1) ◽

Cited By ~ 11

Author(s):

Rattanam AhbiRami ◽

Wan Fatma Zuharah ◽

Maniam Thiagaletchumi ◽

Sreeramanan Subramaniam ◽

Jeevandran Sundarasekar

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Dengue Vector ◽

Plant Parts

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Satyrization without evidence of successful insemination from interspecific mating between invasive mosquitoes

Biology Letters ◽

10.1098/rsbl.2015.0527 ◽

2015 ◽

Vol 11 (9) ◽

pp. 20150527 ◽

Cited By ~ 21

Author(s):

María C. Carrasquilla ◽

L. Philip Lounibos

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Accessory Gland ◽

Reproductive Interference ◽

Interspecific Mating ◽

Male Accessory Gland ◽

Low Frequencies ◽

Heterospecific Male ◽

Invasive Mosquitoes ◽

The Impact

Previous research has documented low frequencies of interspecific mating in nature between the invasive vectors Aedes aegypti and Aedes albopictus . It is also known that heterospecific male accessory gland substances transferred during mating sterilize A. aegypti but not A. albopictus females, leading to satyrization, a form of reproductive interference. This paper demonstrates that satyrization of A. aegypti by A. albopictus may occur without evidence of successful insemination. Our results show that A. aegypti females, previously exposed to A. albopictus males, are rendered refractory to subsequent conspecific mating even though their spermathecae contain no heterospecific sperm. Additional experiments demonstrating transfer of labelled semen from A. albopictus males to A. aegypti females and low production of viable eggs of females housed with conspecific males, following exposure to A. albopictus males, confirm higher incidences of satyrization than expected, based on heterospecific insemination rates. We conclude that frequencies of satyrization based on detection of interspecific sperm in spermathecae may underestimate the impact of this form of reproductive interference.

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Ovitrap Surveillance of Aedes aegypti and Aedes albopictus in Dengue Endemic Areas in Keramat and Shah Alam, Selangor in 2016

IIUM Medical Journal Malaysia ◽

10.31436/imjm.v17i3.243 ◽

2020 ◽

Vol 17 (3) ◽

Author(s):

Noor Afizah A ◽

Mohd Arif AK ◽

Nazni WA ◽

Lee HL

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Species Level ◽

Dengue Vector ◽

Entomological Surveillance ◽

Minimum Number ◽

Endemic Areas ◽

The Difference ◽

Study Sites ◽

Indoor And Outdoor

Introduction: Entomological surveillance is crucial to determine the abundance of dengue vector and to evaluate breeding areas of Aedes aegypti and Aedes albopictus. The objective of this study is to determine the distribution and breeding preference for both Ae. aegypti and Ae. albopictus in dengue endemic areas. Materials and Methods: Ovitraps surveillance was conducted in two dengue endemic areas; AU2, Keramat and Seksyen 7, Shah Alam, Selangor. A minimum number of 100 ovitraps were deployed for 5 days in the study sites. Samples collected were brought back to the lab and all larvae recovered were identified to species level. Results: The ovitap index (OI) in both localities exceeded the transmission threshold of 10% with the OI recorded ranged from 42.3-79.8% in AU2, Keramat and 16.7-42.9% in Seksyen 7, Shah Alam. Ae. albopictus was the dominant species in AU2 Keramat with the highest ratio Ae. aegypti to Ae. albopictus recorded was 1.00:22.79. Nonetheless, in Seksyen 7, Shah Alam the difference in Ae. aegypti to Ae. albopictus ratio is not really prominent with 1.00:3.61 for ovitraps deployed outdoor and 3.40:1.00 for ovitraps set indoor. It was determined that single infestation of either Ae. aegypti or Ae. albopictus is more frequent for ovitraps deployed indoor and/or outdoor, respectively. It was also determined that mixed infestations were found in this study indicating that both species can oviposit in the same container. Conclusion: This study indicates that OI is still above transmission threshold in both study sites. While Ae. aegypti and Ae. albopictus remain as a dominant indoor and outdoor breeder, respectively, mixed breeding of Aedes species in a same container was also observed.

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Avaliação da produtividade dos criadouros do Aedes aegypti (L.) e Aedes albopictus (Skuse) através dos dados da vigilância em Parati – RJ.

EntomoBrasilis ◽

10.12741/ebrasilis.v5i3.249 ◽

2012 ◽

Vol 5 (3) ◽

pp. 223-226

Author(s):

Eduardo Dias Wermelinger ◽

Adilson Benedito Almeida ◽

Ciro Villanova Benigno ◽

Aldo Pacheco Ferreira

Keyword(s):

Aedes Aegypti ◽

Vector Control ◽

Urban Environment ◽

Aedes Albopictus ◽

Surveillance Data ◽

Dengue Vector ◽

Tree Holes ◽

Dengue Control ◽

Dengue Vector Control

Esse estudo avaliou a produtividade dos criadouros de Aedes aegypti (Linnaeus) e Aedes albopictus (Skuse) no município de Parati através dos dados da vigilância entomológica obtidos pelos métodos preconizados pelo Programa Nacional de Controle da Dengue (PNCD). O maior número de pupas de A. aegypti foi coletado nos ralos (31%), garrafas e latas (23%); e com A. albopictus o maior número foi nas garrafas, latas (24%) e vasos de planta (21%). Do total de pupas obtidas, 84,3% e 79,3% das pupas de A. aegypti e A. albopictus respectivamente foram coletadas em pequenos reservatórios: garrafas, vasos de plantas, pneus, bromélias, oco de árvores e ralos. Essas produtividades contradizem a literatura e podem ser explicadas pelas limitações de acesso aos grandes reservatórios e falha na capacitação dos agentes. Esse estudo chama atenção para a importância que os pequenos reservatórios podem ter na densidade do vetor no meio urbano nacional e conclui que a metodologia de vigilância entomológica usada tem sido ineficaz para identificar os grandes e mais produtivos criadouros. Essa conclusão sugere que essa ineficácia pode ser um fator importante pelos insucessos no combate a dengue no Brasil. Evaluation of Breeding Productivity from Surveillance Data for Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) in Parati, RJ, Brazil Abstract. This study evaluated the pupa-productivity of the entomologic surveillance according methodology used by the official Program for Dengue Control in Brazil (PDCB) for Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) in Parati, RJ, Brazil. The highest number of A. aegypti pupae were found in drains (31%), bottles and cans (23%); and the highest number of A. albopictus pupae were found in bottles and cans (24%), and plant vases (21%). Of the total pupae identified 84.3% and 79.3% of A. aegypti and A. albopictus respectively were collected in small receptacles: bottles, plants vase, tires, bromeliads and tree holes. These productivities are not supported by literature and can be explained by the restrictions of access for the bigger receptacles and lack of training of the agents. The study points out the importance which the small receptacles can have on vector densities in urban environment despite of their productivity and conclude that the entomology surveillance methodology for dengue used in PDCB has no efficacy to identify the bigger and more productive receptacles. This conclusion suggests that this inefficacy can be an important factor for the failures on dengue vector control in Brazil.

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