Rabies is a serious viral disease affecting animals and humans, prevalent in most countries throughout the world. There are at least 50,000 deaths annually throughout the world from rabies. Some countries have never had the disease and some have managed to eliminate it. Currently the list of rabies-free countries includes Australia, New Zealand, the South Pacific islands including Guam, Hawaii, Singapore, the United Kingdom, Ireland, Belgium, the Netherlands, Norway, Sweden, Finland, Iceland, Japan and Taiwan(ROC).
HOW THE DISEASE IS TRANSMITTED
The rabies virus is transmitted to humans through the saliva of an infected mammal. The most common animals involved are dogs or other canines and bats, but any mammal including cats, raccoons, monkeys, etc is capable of transmitting the virus. Although an animal bite is the usual way in which the virus gets into the body, because the virus is present in saliva even a scratch which breaks the skin is dangerous. The general rule is that in a country where rabies is present any bite or scratch from any mammal which breaks the skin, however small, needs immediate medical attention.
From the site of the bite or scratch the virus moves along the nerves to the brain. The time taken for this to happen varies enormously - it can take days, weeks, months or even years. This has two implications. When symptoms appear the infecting incident may have been long forgotten leading to a delay in diagnosis, but more importantly, "post-exposure immunisation" to prevent the disease developing is worthwhile even long after the r exposure. Invasion of the brain leads to inflammation (encephalitis) which is widespread and unrelenting. Among the many dreadful symptoms of the inflammation is painful muscular spasm induced by the attempt to swallow so that the patient is in dread of eating or drinking- this symptom gives rise to the alternative name for rabies, fear of water or hydrophobia. Once symptoms appear death is almost inevitable even with special intensive care.
Modern intensive care using a complex, specialised treatment regime has resulted in less than a handful of cures. Therefore prevention is of prime importance. Rabies infection can be prevented by immunisation.
Modern vaccines are safe, effective and relatively pain-free with little in the way of side-effects. Three injections over a period of four weeks are required. Even with this "pre-exposure" immunisation the World Health Organisation recommends a further one or two doses after a possible exposure to make sure that immunity is high.
Because the vaccination course is expensive and the risk of infection is very small for most tourists, immunisation is frequently declined. In such a case should there be an animal bite the injury must be thoroughly cleansed (with antiseptic if available) and medical attention sought as soon as possible- preferably within 24 hours. The course of treatment then involves the use of anti-rabies immunoglobulin to provide some degree of protection through passive immunity while full immunity is induced by a series of 5 injections. Immunoglobulin is very expensive and in general is in short supply so that it may not be available when needed. Not all countries use the same vaccine; nevertheless the "post-exposure" course must be started as soon as possible and continuation of the course and the choice of vaccine can be decided thereafter.