Research Highlights: BGS Traps Could Help Control the Spread of Dengue Fever

BGS Traps Could Help Control the Spread of Dengue Fever

Mosquitos have long been considered a dangerous disease vector in certain parts of the world, spreading not only malaria but other potentially fatal diseases such as dengue fever. Female Aedes aegypti mosquitos transmit this disease to as many as 100 million people every year and about 2.5 billion people currently live in areas with a high risk of dengue infection. There is no vaccine available for this disease, so health professionals must turn to mosquito control in dengue-endemic areas in order to limit infection rates. One proposed method of control is the use of BG-sentinel (BGS) traps: mass-trapping devices that lure in mosquitos and kill them. 
A study recently published in the Journal of Medical Entomology has examined the efficacy of BGS traps in controlling mosquito populations. The study took place in the Cidade Nova neighborhood of Manaus, Brazil, a dengue-endemic area, and approximately 121,135 local residents participated. The study period lasted from February 2009 until June 2010. Experimenters observed twelve clusters of households, each consisting 103-151 households, where six clusters were the experimental group and the other six clusters were the control group. Experimenters installed BGS traps in households that were part of the experimental clusters while the control cluster households received no mass-trapping devices. Experimenters also set up “monitoring” traps in all households to catch mosquitos that were not stopped by BGS traps and thus determine the efficacy of the BGS traps. Experimenters collected these traps biweekly, then examined and counted the trapped mosquitos.
All households also completed questionnaires regarding number of household members, ages of household members, education, neighborhood familiarity and solidarity, current application of mosquito control measures, and other factors that could affect the differences between the control and experimental groups, and thus affect the accuracy of the study results. Though these questionnaires showed statistically significant differences in neighborhood solidarity and familiarity between the two groups, all other variables were similar between the groups.
The results of this study showed that households using BGS traps had reduced numbers of female Aedes aegypti mosquitos present in their homes during rainy months, but there was no difference in mosquito populations during dry months. Though fewer cases of dengue infection were reported among households using BGS traps than the control households, this difference was not statistically significant. Therefore, though this study showed BGS traps to be a potentially effective solution for mosquito control under some circumstances, these results do not provide evidence for the efficacy of BGS traps on a larger scale. More research is thus needed to fully understand the role of newer mass-trapping techniques in mosquito control. 

J. Med. Entomol. 2014; 51(2): 408-420


Caroline Russell-Troutman is the 2013-2014 Research Highlights Editor