Cases of a tick-borne disease, called babesiosis, more than doubled in some Northeastern states between 2011 and 2019, researchers from the Centers for Disease Control and Prevention (CDC) reported last week. This disease is transmitted through the black-legged tick (shown at left), also known as the deer tick and the same tick which transmits Lyme Disease.

Although many people with babesiosis are asymptomatic, others develop flulike symptoms, including fevers, chills, sweats and muscle aches. The disease can be severe or even fatal in people who have compromised immune systems or other risk factors.

The disease, which for decades was extremely rare in the United States, is now endemic in 10 states in the Northeast and the Midwest, the agency said. New York and Connecticut are two states in which it is most common. The increase may have been fueled by rising temperatures and the growing population of deer, two factors that help ticks thrive, experts said.