RABIES

Rabies is a virus that invades the central nervous system and produces an acute, progressive encephalitis (inflammation of the brain) that ends in death. It is usually transmitted via the saliva of a rabid animal:

• Through a bite
• Through contamination of scratch wounds
• Via mucosal membranes.

Rabies occurs only in mammals, so it is not present in birds, reptiles, amphibians or fish.
Rabies can be transmitted from infected animals to humans (zoonosis), which makes it a serious public health concern. Each year in Canada, approximately 3,000 people receive post-exposure treatment as a result of contact with rabid animals. In 60% of those cases, the contact is with rabid dogs or cats.

Rabies has gained a strong foothold in Canadian wildlife, growing in prevalence over the past two decades. Foxes, skunks, and raccoons are amongst the most common carriers of the disease. The presence of these animals in urban and suburban environments means chance encounters with pets is a very real possibility.

Rabies virus can be transmitted in the saliva up to seven days prior to the appearance of any clinical signs.¹
Therefore, all bites to humans should be reported and handled as if they were suspicious — including evaluating, isolating and observing the animal for 10 days — regardless of clinical signs.

CATTLE & SHEEP (rabies may also occur in goats and llamas)

• Incubation period is approximately 14 to 26 days.
• The first observed signs are often hypersalivation and loss of appetite as well as behavioral changes.
• Muzzle tremors usually occur.
• After a few days, anorexia, foamy hypersalivation and loss of weight are often reported.
• Voice modification (bellowing), digestive signs such as tenesmus and constipation, and paresis or paralysis often occur two days after initial signs.

1 Fekadu M, Shaddock JH, Baer GM. Excretion of rabies virus in the saliva of dogs. J Infect Dis. 1982;145:(5):715-719.
2 Ceccaldi P-E. The pathogenesis of rabies. RABIES: Guidelines for Medical Professionals, Veterinary Learning Systems. 1999.
³ Chomel BB. Rabies exposure and clinical disease in animals. RABIES: Guidelines for Medical Professionals, Veterinary Learning Systems. 1999.