Conferencia Dra. Bartholomay

Expanding the toolbox for blacklegged tick (Ixodes scapularis) control

Bartholomay, Lyric¹

¹ Pathobiological Sciences, University of Wisconsin.  Madison, Wisconsin, USA.
E-mail address: lbartholomay@wisc.edu 

Ixodes scapularis, the blacklegged tick, is the most epidemiologically significant vector in the United States for its role in transmission of Borrelia burgdorferi.  There are an estimated 476,000 cases of Lyme Disease in the U.S. annually.   The Midwest Center of Excellence for Vector-Borne Disease (MCEVBD) is anchored at the University of Wisconsin-Madison, and is a collaborative effort between universities, health departments and vector control agencies to prevent tick and mosquito exposures and thereby tick- and mosquito-borne disease.  Tick control approaches significantly lag behind those for mosquito control.  In response, the MCEVBD is casting a broad net to scrutinize and optimize techniques to improve tick control both on-host and in the environment.  For on-host tick control, we are investigating strategies to optimize delivery of acaracides to rodent and deer hosts.  This includes investigating landscape determinants to maximize white-footed mouse interactions with tick tubes (which contain acaracide-treated cotton) and developing methods to increase the repertoire of rodents that visit bait stations for acaracide treatment.  For environmental blacklegged tick control, we have developed a pipeline to screen efficacy and effectiveness of traditional insecticides and Minimum Risk Pesticides (MRP) composed of essential oils, which may be better received given public perceptions of need to control ticks balanced with concerns about traditional, synthetic insecticides.  The pipeline consists of an immersion bioassay in the laboratory, a sachet-based assay to contain ticks for semi-field trials, and a field trial at a site with a high density of nymphs.  This is coupled with a spray assessment protocol for backpack sprayer and fogger equipment that is regularly used for pest control.  To date, we have screened 16 of these products in the laboratory and semi-field settings, and down-selected 4 for field trials.  None of the MRP screened provides significant, sustained control of blacklegged ticks in a field setting. This work provides a comprehensive roadmap for acaracide screening for Ixodes scapularis.

Keywords: Ixodes scapularis, tick, control.