Suppression of Dengue Transmission by Application of Integrated Vector Control Strategies at Sero-Positive GIS-Based Foci

Abstract

A serological survey of primary school children from six schools in Chachoengsao Province, Thailand, was performed at the end of the peak of dengue transmission. GIS analysis of sero-positive cases was carried out to determine transmission foci. Vector control implementation was conducted in the foci and also within 100 meters around the foci in the treated areas by community participation in collaboration with the local government. Vector control strategies included source reduction together with the use of screen covers, a combination of Bacillus thuringiensis subsp. israelensis and Mesocyclops thermocyclopoides, and lethal ovitraps. Implementation of vector control strategies in the foci was continued until the end of the rainy season. Vector control effectiveness was monitored using entomological, serological, and clinical parameters. Results showed a significant reduction of dengue vectors as well as a decrease in sero-positive children and clinical cases in treated areas when compared with untreated areas.

Laboratory and field evaluation of the effects of the neonicotinoid imidacloprid on the oviposition response of Aedes (Stegomyia) aegypti Linnaeus (Diptera: Culicidae)

“…They have been considered to be important tools to fight Ae. aegypti-borne diseases and are used for both monitoring (Surendran et al 2007) and controlling (Ritchie & Long 2003, Kittayapong et al 2008 vector populations. In this study, we evaluated whether the addition of imidacloprid to standard ovitraps would inhibit the hatching of Ae.…”

Predators indirectly control vector-borne disease: linking predator–prey and host–pathogen models

“…These control efforts helped eradicate the vector from 32 of the 37 communities; no new dengue cases were reported in any of the treated communities over a period of several years (Kay & Nam 2005;Nam et al 2005). The introduction of Mesocyclops in combination with other control measures also led to a significant reduction in dengue cases in Chachoengsao Province, Thailand (Kittayapong et al 2008), and larvivorous fishes significantly reduced the long-term (.12 months) density of A. aegypti in rural Cambodia (Seng et al 2008).…”

Biological Control of Dengue Vectors

“…For example a simple and effective way of increasing and transporting copepod populations has been devised in Vietnam using polystyrene blocks (Nam, et al 2000). Fish can be farmed where needed and locally-produced Bti was used in a trial in Vietnam where dengue transmission was successfully suppressed (Kittayapong et al 2008). However, there are some tools whose biological characteristics do not lend themselves to intentional deployment such as the corixid bug Micronecta quadristrigata.…”

“…Not only did they report a dramatic reduction in the number of Aedes positive containers, but there was also a significant reduction in adult Aedes mosquitoes. Crucially, there were no dengue cases reported in the treated area, whilst in the control there were 322.2 cases per 100,000 people; baseline data was similar for the two areas at around 230 cases per 100,000 (Kittayapong, et al 2008). Similarly, a programme utilising all the major categories of intervention was carried out in Taiwan between 1987 and 1993 (Chen, et al 1994).…”