A vaccine for human babesiosis: prospects and feasibility

Babesiosis is a tick-borne disease caused by intraerythrocytic Babesia parasites. It is a well-known illness in companion animals and livestock, resulting in substantial economic losses in the cattle industry. Babesiosis is also recognized as an emerging zoonosis of humans in many countries worldwide. There is no vaccine against human babesiosis. Currently, preventive measures are focused on vector avoidance. Although not always effective, treatment includes antimicrobial therapy and exchange transfusion. In this review, we discuss the host’s immune response to the parasite, vaccines being used to prevent babesiosis in animals, and lessons from malaria vaccine development efforts to inform the development of a human babesiosis vaccine. An effective human vaccine would be a significant advance towards curtailing this rapidly emerging disease. Human babesiosis, a tick-borne disease caused by intraerythrocytic Babesia parasites, is recognized as an emerging zoonosis and global health challenge.Current preventive measures for humans are limited to avoidance of the tick vector. Treatment involves antimicrobial therapy and exchange transfusion; these are not always effective, especially in immunocompromised individuals.There is currently no vaccine for human babesiosis, but such a vaccine could be targeted to at-risk populations to prevent infection, severe disease, and death.Knowledge of immune responses associated with control/elimination of the Babesia parasite, babesiosis vaccine strategies successfully employed in other host species, and recent advances in vaccine development for the closely related Plasmodium parasite could all be used to inform and accelerate development of a human babesiosis vaccine.