38.1  Rabies

Rabies is a severe life-threatening viral disease, transmitted to humans in saliva in the bite of infected animals, particularly those in the dog family (canines). Foxes, wolves, hyenas, bats, raccoons and skunks are also a reservoir of rabies virus, but in most countries they rarely transmit the disease. Bats are the main cause of rabies transmission in the USA and Canada.

The infectious agent of rabies is a virus in the rhabdovirus family, which attacks the nervous system. If an infected person is not treated very quickly, death is almost inevitable (i.e. rabies has a very high case-fatality rate). The WHO estimates that around 55,000 people die from rabies every year, and 24,000 of them are in Africa; 99% of these deaths are the result of a bite from a dog (Figure 38.2).

Figure 38.2  A bite from a dog infected with rabies virus is the source of 99% of human deaths from rabies. (Photo: CDC Image Library, image 8319)