An acute and potentially fatal disease, caused by a rhabdovirus called Lyssavirus, which affects the nervous system of animals, particularly carnivora, and may be communicated from them to humans. Infection from person to person is very rare, but those in attendance on a case should take precautions to avoid being bitten or allowing themselves to be contaminated by the patient’s saliva, as this contains the causative virus.
The disease is ENDEMIC in dogs and wolves in some countries; an EPIDEMIC may occasionally occur. It also occurs in foxes, coyotes and skunks, as well as in vampire bats. Thanks to QUARANTINE measures, since 1897 rabies has been rare in Great Britain, which still retains strict measures (the Rabies Act) to prevent the entry of infected animals into the country, including a six-month quarantine period and vaccination (see IMMUNISATION). This policy was relaxed somewhat in 2001 with the launch of the Pet Travel Scheme; this allows cats and dogs to enter the UK from speci?ed countries without the need for quarantine, as long as stringent conditions as to microchipping and vaccinations are met. Full details can be obtained from the Department for the Environment, Food and Rural A?airs (DEFRA) or from a veterinary surgeon engaged in operating the scheme. Six months has to elapse between vaccination against rabies and a positive blood test before the ‘pet passport’ can be issued.
Rabies is highly infectious from the bite of an animal already affected, but the chance of infection from di?erent animals varies. Thus only about one person in every four bitten by rabid dogs contracts rabies, whilst the bites of rabid wolves and cats almost invariably produce the disease.
Symptoms In animals there are two types of the disease: mad rabies and dumb rabies. In the former, the dog (or other animal) runs about, snapping at objects and other animals, unable to rest; in the latter, which is also the ?nal stage of the mad type, the limbs become paralysed and the dog crawls about or lies still.
In humans the incubation period is usually 6–8 weeks, but may be as short as ten days or as long as two years. The disease begins with mental symptoms, the person becoming irritable, restless and depressed. Fever and DYSPHAGIA follow. The irritability passes into a form of MANIA and the victim has great di?culty in swallowing either food or drink.
Treatment The best treatment is, of course, preventive. Local treatment consists of immediate, thorough and careful cleansing of the wound-surfaces and surrounding skin. This is followed by a course of rabies vaccine therapy.
Only people bitten (or in certain circumstances, licked) by a rabid animal or by one thought to be infected with rabies need treatment; this is with rabies vaccine and antiserum and one of the IMMUNOGLOBULINS. A person previously vaccinated against rabies who is subsequently bitten by a rabid animal should be given three or four doses of the vaccine. The vaccine is also used to give protection to those liable to infection, such as kennel-workers and veterinary surgeons. Those who develop the disease require intensive care with ventilatory support, despite which the death rate is very high.... rabies
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