Feline babesiosis in South Africa: a review.

Babesia felis, originally identified in wild cats in the Sudan, was subsequently found to cause clinical disease in domestic cats. Although babesiosis in domestic cats has been reported sporadically from various countries, as a significant disease it appears to be a distinctly South African phenomenon. Apart from an inland focus, feline babesiosis is reported regularly only from coastal regions. The infection is assumed to be tick-borne, but the vector has not been identified. Feline babesiosis tends to be an afebrile, chronic, low-grade disease. The most frequently reported complaints by owners are anorexia and lethargy. The main clinical findings are anemia, depression, and occasionally icterus. Concurrent infections (e.g., Mycoplasma haemofelis, FeLV, FIV) may contribute to the clinical picture. Laboratory findings commonly include regenerative anemia, elevation of alanine transaminase (but not alkaline phosphatase) and total bilirubin concentrations, and a variety of electrolyte disturbances. Secondary immune-mediated hemolytic anemia can be seen occasionally. Drugs effective against other Babesia species give variable and questionable results. The drug of choice is primaquine phosphate, which effects a clinical cure but does not sterilize the infection. Repeated or chronic therapy may be required.