As the summer season approaches, bringing with it an increase in outdoor activities, Connecticut officials have announced the first U.S. case of the invasive longhorned tick carrying Ehrlichia chaffeensis. This bacteria is known to cause a potentially life-threatening disease known as human monocytic ehrlichiosis (HME). The Connecticut Agricultural Experiment Station (CAES) has stated that initial symptoms of HME include sudden high fever, chills, and fatigue, which typically appear a few weeks after infection.
The progression of HME can lead to more severe symptoms such as nausea, confusion, kidney failure, and respiratory complications. Traditionally, HME is spread by the lone star tick, a species native to the U.S. and prevalent in most of the eastern, southeastern, and south-central parts of the country, as per the Centers for Disease Control and Prevention.
However, the recent case in Connecticut involved the longhorned tick, a species native to eastern Asia. The significance of this tick carrying the bacteria and spreading HME is due to the invasive species’ expected spread throughout the eastern U.S. This is attributed to the tick’s ability to reproduce without a male and its unrestricted feeding habits.
Dr. Goudarz Molaei, director of the CAES Passive Tick and Tick-Borne Disease Surveillance Program, stated that the first fully engorged human-parasitizing longhorned tick specimen was recorded by the CAES in 2018 from Fairfield, Connecticut. The first populations of the tick were reported from this county in 2020.
Since then, populations of longhorned ticks have expanded into several towns in Fairfield and New Haven Counties. Individual tick specimens have also been collected from New London and other counties. Officials have expressed concern about the species’ ability to expand their geographic range and their potential to transmit pathogens that could pose a threat to the health of humans, pets, and other animals.
The longhorned tick has been found to transmit a variety of pathogens in the U.S., including those that cause Lyme disease. As such, the spread of this invasive species is a cause for concern, and officials are urging the public to take precautions to avoid tick bites.