Clinical Signs

The Basics

There is no typical rabies case or set of symptoms in any species of animal, though rabies generally takes one of two forms, either furious or dumb.  Animals with furious rabies usually have an increase in activity characterized by agitation.  This can last several days, and is known as the excitation phase. The animal is restless and soon becomes vicious, biting at anything and everything.  A lack of coordination and tremors are often apparent as well.  This excitation phase gradually subsides.  Convulsions, paralysis, and mental and physical exhaustion occur just prior to death.  Those with dumb rabies simply become paralyzed and die shortly thereafter.

Clinical Signs in Wild or Domestic Animals

An important consideration in reaching a clinical diagnosis of rabies in animals, especially wild ones, is that no sign (or series of signs) is typical or characteristic. Signs of other diseases such as distemper, hepatitis, listeriosis, tetanus, botulism and some parasitic diseases are similar to those of rabies. Encephalitic syndromes can also be caused by plant or chemical toxins. These clinical signs are so varied and overlapping that limited confidence should be placed on a clinical diagnosis of rabies. The only sure way to diagnose rabies is with laboratory tests.

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