Aversion of the invasive Asian longhorned tick to the white-footed mouse, the dominant reservoir of tick-borne pathogens in the United States

Abstract

The Asian longhorned tick (Haemaphysalis longicornis) was reported for the first time in the United States of America in 2017 and has now spread across 12 states. The potential of this invasive tick vector to transmit pathogens will be determined through its association to native hosts, such as the white-footed mouse (Peromyscus leucopus) which is the primary reservoir for the causative agent of Lyme disease (Borrelia burgdorferi) and other zoonotic pathogens. We placed larval H. longicornis on P. leucopus, 65% of the larvae (n = 40) moved off the host within a short period of time and none engorged. In contrast, larval black-legged ticks (Ixodes scapularis) did not move from where they were placed in the ear of the mouse. We then conducted a laboratory behavioural assay to assess the interaction of H. longicornis with the hair of potential mammalian host species in the United States of America. H. longicornis larvae were less likely to enter the hair zone of P. leucopus and humans compared to the hair of domestic cats, domestic dogs, and white-tailed deer. Our study identifies a tick-host hair interaction behaviour, which can be quantified in a laboratory assay to predict tick-host associations and provides insights into how ticks select a host.