Canine babesiosis
Also called Tick fever in dogs, piroplasmosis
A tick-borne disease in which Babesia parasites destroy a dog's red blood cells. It can be mild and short, severe and fast, or a long illness of slowly worsening anaemia.
Cause and spread
- Cause
- Protozoal parasites of the genus Babesia: Babesia canis, Babesia vogeli and Babesia rossi, and the small Babesia gibsoni, each carried by different ticks.
- How it spreads
- By the bite of an infected tick. Some dogs that recover stay infected.
Signs to watch for
- Fever, lethargy, weakness and depression
- Loss of appetite and weight loss
- Pale gums from anaemia
- Yellow gums or eyes (jaundice)
- Dark, red-brown urine (haemoglobinuria) in advanced cases
- Sudden collapse in severe cases
Many diseases look alike. Only a laboratory test can tell them apart, so please see a veterinarian for any sick animal.
How it is diagnosed
A stained blood smear is the main test and shows the parasites inside red blood cells. A blood count shows how severe the anaemia is. PCR detects the parasite's genes and tells the Babesia species apart, which helps because other diseases and co-infections look similar.
- Usually the first testComplete Blood Count (CBC)Shows anaemia and a low platelet count.
- Usually the first testBlood Smear ExaminationLooks for the parasite inside red blood cells.
- Usually the first testBasic Haemoparasite Panel (CBC + Blood Smear) (panel)Blood count and blood smear together.
- Confirms the diseaseBabesia canis PCRDetects Babesia canis.
- Confirms the diseaseBabesia gibsoni PCRDetects the small Babesia gibsoni.
- Confirms the diseaseBabesia vogeli PCRDetects Babesia vogeli.
- Confirms the diseaseCanine Haemoparasite PCR ProfileBabesia canis, B. vogeli, B. gibsoni and Hepatozoon canis in one test.
- Confirms the diseaseHaemoprotozoan PCR Profile (Advanced)A wider profile of blood parasites.
- Supports the diagnosisTotal BilirubinRaised when jaundice develops.
Prevention and control
- Use tick-control products and remove ticks promptly
- Check your dog for ticks after walks and in tick-infested places
- A vaccine exists but does not cover all Babesia types; ask your veterinarian
Where this information comes from
- Babesiosis in Animals · Merck Veterinary Manual
General information for animal owners and veterinarians, last checked October 2026. It does not replace the advice of your veterinarian, who should decide which tests and treatment your animal needs.