NEW HAVEN, Conn. (WTNH) – Tick-borne illness cases in the United States are up 25% since 2011, according to a new report from the Centers for Disease Control and Prevention, including a rare disease now spreading in the U.S. Northeast.

The CDC says cases of babesiosis, which can cause illness ranging from asymptomatic to severe, have increased significantly in Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island and Vermont. The disease is already considered endemic in Connecticut, Massachusetts, Minnesota, New Jersey, New York, Rhode Island and Wisconsin.

The tick-borne disease, which is growing in cases but still rare, is transmitted from the bites of black-legged ticks. 

Babesiosis infections can be asymptomatic or cause mild to severe illnesses that can be fatal. Symptoms, which can last for several weeks, typically show up between one and four weeks after a bite. The most common symptoms include fever, chills, sweating, fatigue, and myalgias. They also include hepatosplenomegaly, or an enlarged liver, and hemolytic anemia, a disorder that causes red blood cells to be destroyed faster than they can be created.

Yale scientist Goudarz Molaei told Nexstar’s WTNH one of the factors that could be causing the increase in tick-borne diseases could be shorter winters. 

“Understandably because of climate change and other environmental conditions we are seeing increases in tick abundance and tick activity,” Molaei said. 

The CDC states on its website:

Because warmer average temperatures can mean longer warm seasons, earlier spring seasons, shorter and milder winters, and hotter summers, conditions might become more hospitable for many carriers of vector-borne diseases.