Improved BioGents\xae Sentinel trap with heat (BGSH) for outdoor collections of Anopheline species in Burkina Faso and Mali, West Africa

Amadou Guindo,Frederic Tripet,Patric Stephane Epopa,Sidy Doumbia,Abdoul-Azize Millogo,Brehima Diallo,Abdoulaye Diabate,Franck Adama Yao,Mamadou B Coulibaly,Bilkissou Yagoure

doi:10.1186/s13071-020-04527-y

Amadou Guindo, Frederic Tripet + Show 8 more

Open Access

https://doi.org/10.1186/s13071-020-04527-y

Copy DOI

Abstract

BackgroundSince the late 1990s, malaria control programmes have relied extensively on mass bednet distribution and indoor residual spraying. Both interventions use pesticides and target mosquitoes coming indoors either to feed or to rest. Unfortunately, these intensified vector control campaigns have resulted in mosquito populations with high levels of resistance to most of the chemical compounds used against them and which are increasingly exophagic and exophillic, hence difficult to monitor indoors. Consequently, there is an urgent need for novel tools to sample outdoor anopheline populations for monitoring interventions and disease surveillance programmes.MethodologiesIn this study, we tested several modifications and configurations of the BioGents® Sentinel (BGS) trap, designed with the aim to increase its efficacy for sampling malaria vector species. Traps were used with chemical attractants and CO2, and the impacts of trap position, trap colour contrast combination and the addition of a heat source were tested in two studies conducted in the Sudano-Sahelian region of Burkina Faso and Mali.ResultsThe results show that of all the configurations tested, the addition of a heat source to the BGS trap with the original colour combination and an upward positioning resulted in a 1.8- and 5.9-fold increase in host-seeking Anopheles gambiae (s.l.) females in the experiments performed in Burkina Faso and Mali, respectively. BGS with heat traps, referred to as BGSH traps, captured An. gambiae (s.l.), An. pharoensis, An. coustani, Culex and Mansonia spp. Importantly, the results suggest that their efficacy does not depend on the close proximity of nearby hosts in houses.ConclusionsThe results suggest that BGSH traps can be an effective scalable tool for sampling outdoor anopheline vector populations. Further developments enabling CO2 and heat generation for longer periods of time would further improve the trap’s versatility for large-scale surveillance programmes.Graphical

Highlights

Since the late 1990s, malaria control programmes have relied extensively on mass bednet distribution and indoor residual spraying
A first study was carried out in Burkina Faso in September 2016 to assess the benefit of adding a heat source to BioGents® Sentinel (BGS) traps to catch anopheline mosquitoes in a Sahelian context
Burkina Faso experiment A total of 1316 An. gambiae (s.l.) females and 82 males were collected using the BGS traps, in addition to 686 An. pharoensis, 32 An. coustani, 31 Culex spp. and 1384 Mansonia spp. females (Table 2)

Summary

Introduction

Since the late 1990s, malaria control programmes have relied extensively on mass bednet distribution and indoor residual spraying. Vectors bite more frequently earlier in the evening or at dawn when humans are not protected by their bednets [6,7,8] The result of such behavioural changes, in combination with widespread genetic resistance to pesticides, is that in many settings malaria transmission cannot be stopped with currently available scalable vector control tools [9]. Another consequence of these changes is that mosquito surveillance and monitoring tools that are mostly geared to monitoring indoor biting vectors are often ineffective or not scalable for outdoor use [9]

Methods

Results

Conclusion