Immunodeficiency Diseases in Animals

Immunodeficiency diseases manifest clinically as a predisposition to infections. They are usually recognized when an animal makes multiple visits to a veterinarian for infections that would normally be relatively easy to control. Two major groups of immunodeficiency disease occur:

• One group is inherited as a result of mutations or other genetic disease. These primary or congenital immunodeficiency diseases usually develop in very young animals (< 6 months).

• The second group of immunodeficiency diseases is secondary to some other problem, such as a viral infection or tumor. These secondary or acquired diseases tend to occur in adult animals.

One other general rule in diagnosing immunodeficiencies is that defects in the innate and antibody-mediated immune systems tend to result in uncontrollable bacterial infections, whereas defects in the cell-mediated immune system tend to result in overwhelming viral and fungal infections.