High resurgence of dengue vector populations after space spraying in an endemic urban area of Thailand: A cluster randomized controlled trial

Napadol SUDSOM; Kuaanan TECHATO; Suwich THAMMAPALO; Virasakdi CHONGSUVIVATWONG; Theerakamol PENGSAKUL

Return

High resurgence of dengue vector populations after space spraying in an endemic urban area of Thailand: A cluster randomized controlled trial

Author: Napadol SUDSOM ¹ ; Kuaanan TECHATO ¹ ; Suwich THAMMAPALO ² ; Virasakdi CHONGSUVIVATWONG ³ ; Theerakamol PENGSAKUL ⁴
Author Information

1. Faculty of Environmental Management, Prince of Songkla University
2. Office of Disease Prevention and Control
3. Epidemiology Unit, Faculty of Medicine, Prince of Songkla University
4. Faculty of Medical Technology, Prince of Songkla University
Publication Type:Journal Article
Keywords: Aedes aegypti; Cluster randomized controlled trial; Dengue; Space spraying; Ultra low volume
From:Asian Pacific Journal of Tropical Biomedicine 2015;5(11):965-970
CountryChina
Language:Chinese
Abstract: Objective: To examine the resurgence rate, house density index (HDI) and parous rate of the Aedes aegypti vector after space spraying carried out by the routine spraying team, and compare with the rates after standard indoor ultra low volume (SID-ULV) spraying carried out by the trained research spraying team. Methods: Between March and September 2014, a cluster randomized controlled trial including 12 clusters (6 regular ULV, 6 SID-ULV) with totally 4. 341 households was conducted, and around 20-31 houses in each cluster were selected for assessment. The parous rate and HDI of collected mosquitoes 2 days before and 1, 2 and 6 days after spraying were obtained and compared. Results: The HDI dropped significantly from the baseline 1 and 2 days after spraying to a non-zero value in the SID-ULV treated locations but not in the regular ULV group locations. However, by 6 days after spraying, the HDI of both groups had returned to the base value measured 2 days before spraying. There were no statistically significant differences in the parous rate between groups. Conclusions: SID-ULV is more effective in reducing Aedes aegypti populations. However, rapid resurgence of dengue vector after spraying in urban areas was observed in both groups.