Community-Based Control of Aedes aegypti By Using Mesocyclops in Southern Vietnam

Abstract

We previously reported a new community-based mosquito control strategy that resulted in elimination of Aedes aegypti (Linn.) in 40 of 46 communes in northern and central Vietnam, and with annual recurrent total costs (direct and indirect) of only $0.28–$0.89 international dollars per person. This control strategy was extended to four provinces in southern Vietnam in Long An and Hau Giang (2004–2007) and to Long An, Ben Tre, and Vinh Long (2005–2010). In a total of 14 communes with 124,743 residents, the mean ± SD of adult female Ae. aegypti was reduced from 0.93 ± 0.62 to 0.06 ± 0.09, and the reduction of immature Ae. aegypti averaged 98.8%. By the final survey, no adults could be collected in 6 of 14 communes, and one commune, Binh Thanh, also had no immature forms. Although the community-based programs also involved community education and clean-up campaigns, the prevalence of Mesocyclops in large water storage containers > 50 liters increased from 12.77 ± 8.39 to 75.69 ± 9.17% over periods of 15–45 months. At the conclusion of the study, no confirmed dengue cases were detected in four of the five communes for which diagnostic serologic analysis was performed. The rate of progress was faster in communes that were added in stages to the program but the reason for this finding was unclear. At the completion of the formal project, sustainability funds were set up to provide each commune with the financial means to ensure that community-based dengue control activities continued.

Water depth‐dependent notonectid predatory impacts across larval mosquito ontogeny

“…Biological control of mosquitoes using natural enemies can be effective to mitigate the proliferation and emergence of medically important mosquito species (e.g. Kay and Nam and Nam). However, the impacts of predators on prey have been shown to be highly context‐dependent, with both biotic and abiotic factors potentially influencing the impact of consumers within ecosystems .…”

Biological Control of Mosquito Vectors: Past, Present, and Future

“…Copepod biocontrol for Ae. aegypti was still being actively undertaken by communities in Vietnam even after the official intervention had ceased [62,63]. However, there are limitations in terms of the specific mosquito species to which copepods can be efficiently applied, since the larval habitats of many mosquito species are not suitable for copepods [64].…”

Field trial on a novel control method for the dengue vector, Aedes aegypti by the systematic use of Olyset® Net and pyriproxyfen in Southern Vietnam

“…Treatment of such breeding sites with insecticides based on organophosphates or insect growth regulators, some of which are recommended for the treatment of drinking water by WHO, seems to be the best and most convenient measure. However, the use of insecticides to control mosquitoes at their breeding sites has not been approved for the treatment of drinking water in Vietnam, which uses community-based biological control strategies for this purpose, for example, by the use of the copepod, Mesocyclops [6,11,12]. However, this form of control is lost from containers when all the water is used up or the containers are cleaned [13], which then makes larval vector control difficult.…”

“…aegypti in southern Vietnam where over 80% of dengue cases of the country are reported each year, and where Ae. aegypti may be more abundant than in the northern and central parts of Vietnam [11]. Flower vases and ant traps are also important breeding sites for Ae.…”