Development and field evaluation of a motion sensor activated suction trap to study vector-host interactions

1. Researchers elucidating vectors of zoonotic diseases encounter problems with inefficient surveillance techniques leading to underestimation of the importance of some species, and the overestimation of the importance of others. Carbon dioxide-baited light traps are the most widely used traps for sampling vector groups. However aspirating directly from the hosts is the most accurate method to incriminate vectors.

2. A novel vector trapping system was developed, consisting of a suction trap, activated by a motion sensor, and controlled by a microcontroller, which activates automatically when host animals approach. The prototype was tested in two field experiments with ungulates and biting midges (Diptera: Ceratopogonidae) at a preserve in Florida. We measured the biting midge community collected at traps near and far from hosts and compared communities using diversity metrics and abundance curves.

3. Traps activated in the presence of host animals with 94% accuracy. Diversity and richness of Culicoides species differed between sensor and control traps with 11 species captured by control traps and 7 species by sensor traps. Vector species were captured in significantly greater numbers in sensor traps, while more non-vector species were caught in control traps.

4. Results confirm that vector species can be underrepresented in light trap collections, likely due to their tight associations with vertebrate hosts, a finding that should be taken into consideration when incriminating arbovirus vectors. Our novel trap system was a first attempt at solving the issue of collecting vector species from non-tame animals, effectively aspirating questing midges. Simple modifications of the system could be made to target other vector-host systems.