Inclusuion Body Disease in Boas and Pythons

IBD is a killer and runs rampant in the herp community. This is a fatal disease. Please be sure to take precautions when purchasing a new boid species and use strict quarentining practices. Don't risk your entire collection.

This article was supplied by Melissa Kaplan at www.anapsid.org


Inclusion Body Disease

©1995 Melissa Kaplan



Inclusion body disease (IBD) has been increasingly diagnosed in boas and pythons ("boids"). It is believed to be a retrovirus. The way it affects these two groups of snakes is slightly different but the long term effects are the same: the disease is terminal in those animals who exhibit symptoms of the disease.

Pythons, although their symptoms may be somewhat less, are just as affected as boas. There are asymptomatic carriers, so the fact that a boa or python within an infected collection does not show signs of the illness should not be taken to mean that it is immune to it. Boas are most associated with being asymptomatic carriers.

Signs of infection in boas include central nervous system disorders such as paralysis, being unable to right itself when turned over, "star-gazing", inability to strike or constrict. Other signs include chronic regurgitation, extreme weight loss, respiratory infections, and dysecdysis due to the inability to control body movements enough to rub off the old skin. The disease is rapidly fatal in young and juvenile boas, typified by rapid onset of flaccid paralysis.

In pythons, the disease progresses much more rapidly than in boas. Along with the above symptoms (excluding the chronic regurgitation), pythons also tend toward infectious stomatitis ("mouth rot"), heightened or exaggerated reflex responses, disorientation (which may be precipitated by the onset of central blindness) and loss of motor coordination.

What causes this disease? Intracytoplasmic eosinophilic inclusion bodies have been identified in the epithelial cells of the kidneys and pancreas. Neuronal degeneration and lesions form in the spinal cord and brain, and may be accompanied by myelin degeneration and nerve damage. Damage to the spleen is also found, with that organ being grossly atrophied and fibrosed. Electron microscopy has found that the organism falls into the retrovirus category.

The snake mite, Ophionyssus natricis, has been found in collections in which IBD has occurred but it is not implicated in all cases of infection.

As this has been identified as a viral entity, it may spread like a virus, through contact between infectious organisms (such as housing an infected snake with a previously healthy one) or through airborne aerosolized secretions, or by the keeper passing secretions from one snake or enclosure to another during the course of handling or cleaning (when strict quarantine and cleaning procedures are not followed).

There is at this time no treatment for the disease and, as it is at this time always fatal and highly contagious, euthanasia is the course of action recommended. Even if the snake can be kept alive through supportive measures (hydration and force-feeding), the damage to the nerves, brain, spinal cord and internal organs is so great--and progressive--that live is only prolonged with an ever decreasing quality and increasing pain.

Due to the increasing incidence of this disease, it cannot be stated or urged strongly enough to QUARANTINE ALL NEW BOIDS upon acquisition for at least 3-6 months, and to take precautions when visiting other collections, pet stores and expos/swaps.