Retrovirus Infection in Snakes

By PetMD Editorial on Sep. 8, 2008

Inclusion Body Disease

Of the many viral diseases that affect snakes, one of the most common and important is caused by the retrovirus that produces inclusion body disease (IBD), an invariably fatal disorderaffects multiple body organs and systems. IBD is most frequently diagnosed in boa constrictors, but can be seen in pythons and other snakes as well.


Symptoms and Types

The symptoms of IBD may appear suddenly, but can also remain invisible and dormant for years, particularly in boas. Signs of IBD include:


  • Weakness
  • Loss of appetite
  • Weight loss
  • Vomiting
  • Skin ulcers
  • Delayed wound healing
  • Bacterial infections


In severe cases or after the virus has been present in the body for a long time, IBD may lead to neurological symptoms including:


  • Mild to severe facial tics
  • Muscle spasms
  • Abnormal tongue flicking
  • Seizures
  • Stargazing
  • Inability to roll into the correct the posture when the animal is on its back


Among infected snakes, boas tend to live longer, while pythons usually die within days or weeks of developing.



The retrovirus responsible for IBD is generally transmitted between snakes through breeding, bite wounds, snake mites, and the ingestion of contaminated droppings. Snakes that are under stress and have a weakened immune system are more susceptible to IBD and can contract the virus if they come in contact with objects that have been used around infected snakes.



If your veterinarian suspects IBD, he or she will perform a blood test to measurepet’s white blood cell count. An increase in the number of white blood cells can indicate an earlyinfection, but as the disease progresses, the count will often fall dramatically. Abnormal structures may also be seen inside of blood cells when a sample is examined under the microscope. A definitive diagnosis, however, is only possible when biopsy samples of internal organs are sent to a pathologist for testing.



Unfortunately, there is no known treatment or cure for IBD at this time. If an infected snake has an acceptable quality of life, it can be isolated and its symptoms managed for a period of time.


Living and Management

If an infected reptile cannot be quarantined away from uninfected snakes, or if it is suffering, euthanasia is the most humane option available.



Help us make PetMD better

Was this article helpful?

Get Instant Vet Help Via Chat or Video. Connect with a Vet. Chewy Health