Increasing Threat of Invasive Ticks in Connecticut Linked to Global Travelers

A new study published in the journal iScience has uncovered that various tick species from other regions, including Ixodes ricinus, are arriving in Connecticut due to their attachment to international travelers. These nonnative ticks, which originated from locations like Belize, Costa Rica, Germany, Guatemala, Poland, Scotland, and Tanzania, have been documented between 2019 and 2023, suggesting an alarming trend of invasive ticks entering the United States.

The research, led by medical entomologist Goudarz Molaei from the Connecticut Agricultural Experiment Station, indicates a rising frequency of nonnative ticks, potentially increasing the prevalence of tick-borne pathogens. The study particularly warned about the Rickettsia amblyommatis bacteria found in ticks from Costa Rica and Guatemala, raising concerns about diseases linked to spotted fever.

In recent years, ticks of all varieties have thrived in the United States, with some species, like the Asian long-horned tick, originating overseas. Ticks are also migrating domestically, with species from warmer Southern regions extending their range northward. Due to a hospitable environment fueled by climate change, these invasive ticks might find it easier to establish themselves in the U.S.

Researchers suggest that warmer winters allow ticks and their host animals, such as deer and mice, to survive longer, which contributes to the increasing number of ticks. The spread of invasive plant species like the Japanese barberry may also be favorable for ticks. Climate change is altering the geographical landscape, making conditions more suitable for ticks that typically thrive in tropical climates.

Connecticut holds significance in tick research, as it is the location where Lyme disease was first identified in the 1970s. The ticks studied were not collected from the wild but were submitted by travelers who discovered them attached to their bodies after returning from abroad. This highlights the necessity of vigilance regarding tick exposure, regardless of travel distance. Health professionals recommend regular tick checks for both humans and pets to prevent potential disease transmission. While this study raises valid concerns, it also stresses the importance of further research rather than causing panic.