Anaplasmosis

Anaplasmosis is an infection caused by bacteria transmitted through tick bites. These bacteria live inside white blood cells and can trigger an immune response that affects how the body functions. Dogs are more commonly affected than cats, and the infection may cause no signs at all in some animals, while others develop illness days to weeks after a tick bite. Owners often arrive at this page after a positive blood test during routine screening, or because their dog has become lethargic, lost appetite, or developed a fever. Some dogs show signs of joint pain or bruising. The pattern of signs can be vague, and many dogs improve on their own without treatment, though others benefit from antibiotics. This page explores what signs may appear, what is happening inside the body during infection, how anaplasmosis is identified through blood tests, and what approaches exist for managing dogs who test positive or develop illness.