Babesia spp. are apicomplexan parasites that infect a wide variety of animals, including humans, causing severe disease in domestic animals and human babesiosis.

Keywords: parasitology; apicomplexa; tick‐transmitted disease; emerging disease

Figure 1.

Current taxonomic classification of babesial parasites.

Figure 2.

The lifecycle of Babesia bovis requires a mammalian reservoir host and a tick vector. Boophilus microplus acquire the parasites in the blood meal and replication within the tick results in transovarial transmission and development of infectivity in the subsequent generation. Tick feeding on susceptible cattle results in transmission of sporozoites that initiate infection of the mature erythrocyte. Intraerythrocytic replication leads to sequential cycles of merozoite release and infection of additional erythrocytes, resulting in clinical disease.



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Further Reading

Gelfand JA and Callahan MV (1998) Babesiosis. Current Clinical Topics in Infectious Diseases 18: 201–216.

Greene CE (1998) Infectious Diseases of the Dog and Cat, 2nd edn. Philadelphia: Saunders.

Kreier JP (1993) Parasitic Protozoa, vol. 5, 2nd edn. San Diego: Academic Press.

Losos GJ (1986) Infectious Tropical Diseases of Domestic Animals. Essex: Longman.

Ristic M and Kreier JP (eds) (1981) Babesiosis. New York: Academic Press..

Ristic M (1988) Babesiosis of Domestic Animals and Man. Boca Raton: CRC Press.

Smith BP (1996) Large Animal Internal Medicine, 2nd edn. St Louis: Mosby.

College of Veterinary Medicine at the University of Missouri. Babesia spp. [∼vmicrorc/Protozoa/Hemosporidians/Babesia.htm]

(ICTTD). Integrated Control of Ticks and Tick‐borne Disease website []

The University of Rhode Island Tick Research Laboratory. Human Babesiosis []

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How to Cite close
Palmer, Guy H(May 2001) Babesiosis. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0001945]