- Coinfection.

The incidence and geographic distribution of human babesiosis is growing in the U.S. Its major causative agent is the protozoan parasite, . is transmitted to humans primarily through the bite of ticks, which are vectors for a number of other pathogens. Other routes of transmission are blood transfusion and in rare cases of mother-to-foetus transmission, through the placenta. This review discusses the current literature on mammalian coinfection with and , the causative agent Lyme disease.