Ticks taking over Tennessee: A snapshot of the past five years

In recent years, the population of ticks has been expanding geographically throughout the United States. This expansion has been accompanied by a rise in several tick-borne diseases. Therefore it’s no surprise that In Tennessee, the past few years have seen the expansion of several tick species populations and the introduction of an invasive tick species along with several tick-borne diseases both in humans and in livestock. Notably, the invasive tick species Haemaphysalis longicornis, first reported in 2019, has since spread into several counties, primarily in Mid and East Tennessee. This study focuses on updating the current distribution of various tick species throughout Tennessee from 2019 to 2024. To achieve this objective, passive surveillance was conducted across several counties in Tennessee, with a particular focus on Mid and East Tennessee. Passive surveillance involved collecting ticks from companion animals, livestock, and wildlife. The collected ticks were identified at the species level, and distribution maps were developed to observe any patterns. Currently, 11 counties in Tennessee have reported the presence of the invasive tick H. longicornis. We anticipate a rapid expansion of H. longicornis throughout Tennessee. Surveillance for ticks is ongoing, and the distribution maps will be updated as data is received. Over the last five years of surveillance, we expect to observe a range expansion of tick populations in Tennessee. This study highlights the importance of continuous passive surveillance to monitor and mitigate the rapid spread of different tick species and associated tick-borne diseases in Tennessee.