Tick responses to diverse chemical attractants to enhance tick surveillance methods' efficacy

Amblyomma maculatum Koch (Acari: Ixodidae), Ixodes scapularis Say, and Dermacentor variabilis Say are three hard-bodied ticks responsible for vectoring pathogens that cause most human tick-borne diseases in the United States of America (USA). Tick surveillance is critical to elucidate high-risk areas for targeted vector control and public health interventions. Despite tick-borne diseases having a higher annual incidence compared to mosquito-borne diseases in the USA, tick traps used for surveillance are grossly under-developed compared to the suite of sophisticated mosquito traps available on the commercial market. This study sought to identify potential prospective tick trap improvements by evaluating the relative attraction of three medically important tick species to odor attractants in a laboratory setting: carbon dioxide, ammonia, deer musk, and rodent musk. This study found that carbon dioxide gas and rodent musk had limited attraction to all three tick species and across life stages. Conversely, this study did find that deer musk and ammonia demonstrated favorable attraction for I. scapularis and D. variabilis across multiple life stages, suggesting standard tick trap techniques might be improved using low-cost and practical alternate attractants. Future field-based studies of these odor attractants, both singularly and in combination with the standard dry ice, are warranted to evaluate potential increased efficacy for broad tick species vector surveillance methods.