A potentially deadly infection carried by the same tick that transmits Lyme disease is emerging along parts of the U.S. eastern seaboard and public health officials are concerned it may be going undiagnosed in many people. Babesiosis is a parasitic infection carried in mice and other rodents. The disease, carried to humans by ticks, attacks the red blood cells and causes symptoms often mistaken for the flu. Unlike Lyme disease, with its distinctive target-shaped rash, tick bites carrying babesiosis are often undetected.
Symptoms appear one to six weeks after a tick bite and can last several weeks or months.
We are concerned that it may be more widespread than we have previously thought. Diagnostic tests are still fairly new so diagnosis is difficult. Babesiosis was recognized in the Northeast in the 1960s and became endemic by the 1980s in Nantucket, Martha's Vineyard, Shelter Island, and parts of Long Island, as well as other areas along the northeastern seaboard, according to Mary Shepherd, who is with the CDC's infectious disease branch. Cases recently have been reported in New Jersey. According to Dr. Sean O. Henderson, an assistant professor at the University of Southern California School of Medicine, hundreds of cases have been reported since the first domestic case in 1966.