Babesia microti

Babesia microti is a species of parasitic protozoan belonging to the genus Babesia. These organisms are classified as apicomplexans, a subclass of Coccidia. Babesia species are known to infect the red blood cells of vertebrates, leading to a condition called babesiosis.12

Babesiosis is a tick-borne disease that can affect both humans and animals. In humans, B. microti is the most common cause of infection, particularly in the United States. The disease is transmitted by Ixodes ticks, which often acquire the parasite from rodents, such as the white-footed mouse. While many infected individuals show no symptoms, some may experience fatigue, fever, headache, and nausea. Severe illness can occur in the elderly or those with weakened immune systems, potentially leading to anemia, jaundice, and organ failure. Treatment typically involves specific medications, and tick control is crucial for prevention.2