Two invasive species of ticks are spreading across Connecticut and bringing the threat of new diseases with them.
A recent study by the Connecticut Agricultural Experiment Station found that the lone star tick and longhorned tick were in twice as many Connecticut counties in 2024 than they were in previous years.
Officials said both species were found in Fairfield, New Haven, Middlesex, and New London counties. In a 2019 study, the two species were only found in New London and Fairfield counties.
More than 4,000 ticks were collected from 40 locations across all eight Connecticut counties during the spring, summer, and fall of 2024 as part of the study. The ticks were then tested for pathogens that can cause diseases in humans.
The most common tick collected was the blacklegged, also known as a deer tick.
The spread of the invasive ticks increase the danger of a variety of tick-related diseases. While the threat of Lyme disease is well known, ticks can carry a variety of other dangerous diseases. For example, a bite from a lone star tick can cause victims to have an allergic reaction to red meat that can be severe.
In 2014, a woman on Long Island woke up with swollen, itchy hands hours after eating a burger. Soon after she could feel her lips and tongue were getting swollen, and by the time she made a phone call for help, she was losing her ability to speak and her airway was closing. A test confirmed the meat allergy.
Officials have described the spread of the lone star tick as a “game-changer” because of its hungry and aggressive nature.
Researchers say unlike the deer tick, the lone star tick can sense the presence of a host, has great vision and will actively follow its target. They are also three times as fast as a deer tick.
Veterinarians have warned that the lone star tick poses a big threat to pets because they tend to attack animals in swarms and they carry diseases that can be deadly to pets.
The lone star tick is identifiable by a white dot on its back.
Deer ticks also can carry diseases other than Lyme. They can also carry the Powassan virus, which has symptoms similar to Lyme disease, including headache, nausea and fever. But once contracted, there is no treatment for the Powassan virus. And, in some cases, it can reportedly be fatal.
New London County reported the highest average adult blacklegged tick density (83 per acre) and the highest average nymphal blacklegged tick density (25 per acre). Pathogen testing revealed the highest adult female infection prevalence in Litchfield County (65%) and the highest nymphal infection prevalence in Fairfield County (41%).
An estimated 476,000 Lyme disease cases (spread by the blacklegged, or deer tick) are treated each year across the United States. Besides Lyme disease, experts say there are an additional 17 other tickborne pathogens of significant medical concern.
Connecticut’s Active Tick Surveillance Program was created in 2019.
“The spread of lone star and longhorned ticks in Connecticut, along with increasing blacklegged tick populations, highlights the importance of continued tick surveillance,” said Dr. Megan Linske, a vector ecologist specializing in tick-host-habitat dynamics at the Connecticut Agricultural Experiment Station. “Residents should take routine precautions and check for ticks after being outdoors.”
To minimize exposure to tick bites, experts recommend the following tips:
- Stay on established trails and avoid bushy or wooded areas.
- Conduct routine tick checks after outdoor activities.
- Wear long sleeves, pants, and light-colored, tightly woven clothing.
- Tuck pant legs into socks when hiking in tick habitat.
- Wear permethrin-treated clothing to repel and kill ticks.