Evaluation of the baited ovitrap with natural attractant for monitoring Aedes spp. in Dili, capital of East Timor

Cien Saude Colet. 2020 Feb;25(2):665-672. doi: 10.1590/1413-81232020252.12512018. Epub 2018 Jun 3.
[Article in Portuguese, English]

Abstract

Dengue transmission has been known in East Timor since 2005, but the country is not equipped with an Aedes aegypti mosquito monitoring and control program. This study aimed to evaluate the baited ovitrap as a possible tool to monitor the arbovirus vector Dengue (DENV), Chikungunya (CHIKV) and Zika (ZIKV) and was conducted in the city of Dili, capital of East-Timor, between epidemiological weeks 32 (02/08) and 48 (02/12) of 2016. In total, 70 ovitraps were installed in residences scattered throughout fifteen streets of four Administrative Posts (districts) of the city. The following entomological indicators were used: Ovitrap Positivity Index (OPI), Vector Density Index (VDI), and Egg Density Index (EDI). A total of 158.904 eggs were collected during the experiment. The OPI showed that 98-100% of traps contained Aedes spp. in all areas of the study. The EDI and OPI indicators were positively and significantly correlated with the temperature. The two- and three-week lag for rainfall indicated a significant positive correlation for VDI and EDI. Therefore, the ovitrap is a tool that can integrate the actions of an Aedes spp. monitoring and control program in East-Timor.

A dengue ocorre no Timor-Leste desde 2005, porém não existe um programa de monitoramento e controle do "Aedes aegypti". O objetivo deste estudo foi de avaliar a armadilha ovitrampa iscada com atraente natural como uma possível ferramenta para monitorar o vetor das arboviroses: Dengue (DENV), Chikungunya (CHIKV) e Zika (ZIKV). O estudo foi realizado na cidade de Dili, capital do Timor-Leste, entre as semanas epidemiológicas 32 (02/08) a 48 (02/12) de 2016. Foram instaladas 70 armadilhas Ovitrampa, em residências de 15 sucos (ruas), de quatro Postos Administrativos (bairros) da cidade. Para as analises dos dados utilizou-se os indicadores entomológicos: Índice de Positividade de Ovitrampa (IPO), Índice de Densidade Vetorial (IDV) e Índice de Densidade de Ovos (IDO). Durante o experimento foram coletados 158.904 ovos de Aedes spp.. O IPO demonstrou que todas as áreas tiveram 98% a 100% de armadilhas contendo ovos de Aedes spp.. Os indicadores IDO e IPO apresentaram correlações positivas e significativa com a temperatura. A defasagem de duas e três semanas para precipitação indicou correlação positiva significativa para IDV e IDO. Portanto, a armadilha ovitrampa é uma ferramenta que pode integrar as ações de um programa de monitoramento e controle de Aedes spp. no Timor-Leste.

MeSH terms

  • Aedes / physiology
  • Aedes / virology*
  • Animals
  • Chikungunya Fever / prevention & control
  • Chikungunya Fever / transmission
  • Chikungunya virus / isolation & purification
  • Dengue / prevention & control
  • Dengue / transmission
  • Dengue Virus / isolation & purification
  • Female
  • Humans
  • Mosquito Control / methods*
  • Mosquito Vectors / virology*
  • Oviposition
  • Timor-Leste
  • Zika Virus / isolation & purification
  • Zika Virus Infection / prevention & control
  • Zika Virus Infection / transmission