Babesiosis, sometimes referred to as “American malaria,” is caused by the Babesia parasite and is transmitted from bites of black-legged ticks. It’s found primarily in Northeastern and Midwestern states. Like malaria, the parasite infects red blood cells, and the condition shares many similar clinical symptoms. According to the U.S. Centers for Disease Control and Prevention (CDC), although some people do not develop symptoms, others experience flu-like symptoms. The disease can be deadly for older adults and those with certain health conditions, such as a weakened immune system or lack of spleen.