What is rabies?
Rabies is a viral infection of the nervous system that can infect almost all mammals, including humans. Foxes, dogs, raccoons, bats and skunks can all act as reservoirs for rabies. Worldwide, the principal hosts for rabies are the domestic dog, and bats, particularly insect eating bats. Once infected, the virus becomes concentrated in an infected animal's saliva and is passed on through the animal's bite. It can also be passed on by contact of infected saliva through scratches, licks on broken skin and mucous membranes. It is one of the oldest recognised diseases in man. Rabies is a notifiable disease in Ireland.
How does rabies make you ill?
After being bitten by an infected animal, the disease usually incubates for about 3 to 8 weeks, but can be very variable. The virus multiplies in the initial wound and spreads through the nerves to the spinal cord and brain. When the virus reaches the brain, it rapidly multiplies and passes to the salivary glands. After this time early symptoms of malaise, fever, or headache followed by anxiety, convulsions and paralysis appear. Due to spasm of throat muscles, an affected person may find it difficult to swallow even water (hydrophobia). Not everyone who is bitten by a rabid animal will develop the disease. By the time symptoms develop, the disease has become very advanced and it is almost always fatal.
Can rabies be treated?
There is a vaccine against rabies, licensed for use in Ireland, that is very effective at preventing the disease. The vaccine works by stimulating the body's defences to produce antibodies that will neutralise the rabies virus. When someone is strongly suspected of having been bitten by a rabid animal, specific antibody (called immunoglobulin or Ig) is also given at the same time as the vaccine, regardless of whether the person has been immunised in the past. This gives a booster dose of antibody that provides a very high dose of antibodies to combat the rabies vaccine. The earlier the vaccine and immunoglobulin are given, the better are the chances of survival. If given within hours of a bite recovery is generally 100%. Once symptoms of encephalitis appear (confusion, paralysis, coma), the disease is almost invariably fatal.
Where is rabies found?
Rabies is found in Asia, Africa, and Central and South America, but it also can be found in northern Europe. In developed countries such as the United States very few people die of rabies, despite the disease being quite common among animals there.
Throughout the world, however, according to the World Health Organization, 40,000 people die of the disease each year. At least 30 countries, including Ireland, are officially rabies-free, usually because of strict regulations about animal movement. There has not been a case of rabies in animals in Ireland since 1902.
How likely are you to catch rabies?
Rabies is very hard to contract. A deep bite from a rabid animal is the most likely way in which it can be passed on. Although possible, the likelihood of contracting rabies from licks of a rabid animal or from touching a rabid animal is tiny.
Are bats a risk?
A tiny proportion of bats in Europe carry bat rabies (caused by European Bat Lyssavirus - very similar to normal or sylvatic rabies). Bats carrying rabies have been identified in the UK and there is at least one instance of a British bat handler dying of rabies following a bat bite. As bat populations are potentially quite mobile, the supposition must be that bats carrying rabies can fly to Ireland and so, given the seriousness of rabies, the assumption must be that any bat in Ireland (most especially a species known as Daubenton's bat) poses a risk of rabies. Accordingly, if a person is bitten by a bat in Ireland, they will be offered rabies preventive treatment, on the very slender possibility that they may have been exposed to the virus. However, it must be remembered that the likelihood of a member of the general public contracting rabies from a bat is extremely small; and it would only be in the circumstance where a bat were to bite a person that the disease could be spread.
Bats are a protected and valuable species. It is important that members of the public should not approach a bat they come across. If a bat is seen during the day or allows a person to approach them, they are unwell and should not be approached. Bats should only ever be approached and handled by those trained and qualified to do so. By avoiding bats, members of the general public will have a risk of developing rabies that is very close to zero.
What can be done if one is bitten by a rabid animal?
If bitten, and treated straightaway, the risk of dying is tiny. The wound should be cleaned thoroughly with soap and water. The person should then seek immediate medical attention. Vaccination and, occasionally if medically indicated, immunoglobulin are given. This would be particularly important for bites acquired outside the UK and Ireland.
Who should be immunised against rabies?
Various groups of people should be immunised against rabies. Groups for whom vaccination should be considered include: anyone who travels to remote places where medical treatment may not be available; people who handle bats; anyone whose work involves working with imported animals; health and laboratory workers who work with the virus. The vaccine comes in three doses, and should be boosted every two or three years. It is a very safe vaccine with few side effects and is virtually 100 per cent effective.
Where can I get further information on Rabies?
The European Centre for Disease Prevention and Control has extensive rabies information.
The World Health Organization has a rabies factsheet.
Rabnet is the World Health Organization's public access database on human and animal rabies.
The Centers for Disease Control and Prevention provide an excellent rabies portal.
Last reviewed: 25th June 2015
- Measles outbreak investigation in Kerry and West Limerick
25 May 2016
- HSE investigating case of measles
13 May 2016
- Measles outbreak in London - April 2016
29 April 2016
- Zika virus disease epidemic: potential association with microcephaly and Guillain-Barré syndrome – Updated risk assessment and travel advice
02 February 2016