Canine Babesia new to North America.

A domestic dog residing in New England suffered a fatal febrile illness caused by a Babesia infection. The morphology of these intraerythrocytic protozoa and the range of hosts that could be infected experimentally suggested that the parasite was B. gibsoni. Although this tick-bourne disease is enzootic in wild and domestic Canidae in Africa and Asia, it appears to be new to the Americas.