Babesia gibsoni is a parasite that infects red blood cells and can lead to anemia. This is a species that falls under the overarching genus Babesia. It is transmitted by the brown dog tick (Rhipicephalus sanguineus) and is one of the most common piroplasm infections. The brown dog tick is adapted to warmer climates and is found in both Europe and the United States, especially in shelters and greyhound kennels. In Europe, it is also transmitted by Dermacentor ticks with an increase in infections reported due to people traveling with their pets.