Thursday May 24 2012
New UK rabies case 'poses negligible risk to the public'
The Health Protection Agency (HPA) has confirmed a case of rabies in London. The patient became infected after being bitten by a dog in South Asia, but is now being treated in the UK. The HPA says the risk to others is “negligible”, but as a precautionary measure health staff and people who have had close contact with the patient are being examined and vaccinated when necessary.
The case featured widely in today’s newspaper reports, often accompanied by images of vicious-looking dogs preparing to attack. However, it’s important to note that rabies does not circulate in either wild or domestic animals in the UK, so the risk of catching it through a pet bite is virtually non-existent here. Equally, rabies is only passed on through injuries such as bites and scratches (and not through airborne particles), so it seems highly unlikely that the infection could spread beyond this patient. Rabies is very rare in the UK. Four cases have been identified here since 2000, all of which were acquired from dog bites abroad.
Some internet sources have highlighted that bats in the UK carry a rabies-like virus. While this is true, bats feed on insects rather than human blood, and therefore pose a negligible risk for the general public.
What is rabies?
Rabies is a very serious viral infection that affects the brain and central nervous system. It is called a “zoonotic” infection, which means it passes from animals to humans. The virus is transmitted to humans through animal bites, and can’t spread through physical contact or airborne means in the way that other zoonotic infections can. This means it does not spread from human to human. Despite around 55,000 cases of rabies globally each year, there has yet to be a single confirmed case of human-to-human transmission.
Initial symptoms can include anxiety, headaches and fever. As the disease progresses, there may be hallucinations and respiratory failure. Spasms of the muscles used for swallowing make it difficult for the patient to drink. The incubation period between being infected and showing symptoms is between two and eight weeks, depending on the site of the initial infection.
Once symptoms have developed, rabies is almost always fatal, although a small number of people are reported to have survived.
How did the patient get it?
The HPA has confirmed that this case of rabies is in a London patient who became infected after receiving a dog bite in South Asia. Some newspapers have reported that the patient is a woman in her 50s who was bitten by a puppy in India and that she is in intensive care at the Hospital for Tropical Diseases, London, but these details haven’t been officially confirmed.
Is there any risk to the public from this case?
The HPA has stressed that this case poses no real risk to the general public or to patients and visitors at the hospital where the patient is receiving treatment. As a precautionary measure, family members and healthcare staff who have been in close contact with the patient since they became unwell have been assessed and offered a vaccination against rabies, where appropriate. Once again, the rabies risk during this “infectious period” is negligible as the patient would have to somehow transmit the virus to another person’s bloodstream.
How common is rabies?
There are an estimated 55,000 cases of rabies each year worldwide, with most cases occurring in the developing world. The vast majority of cases occur after a bite from an infected dog.
The UK has been rabies-free since the beginning of the 20th century, with the exception of a rabies-like virus in a single species of bat (see below). The last recorded rabies case in the UK was in Northern Ireland in 2008. In that instance, the patient had been working for an animal charity in South Africa. A small number of cases continue to be reported in other developed countries, most being the result of a bite from a wild animal rather than a domestic dog.
How is it spread?
Rabies is transmitted through the saliva of an infected animal and can be caught if an infected animal bites or scratches a human. It may also be transmitted if the saliva from an infected animal comes into contact with a graze or cut on someone’s skin. Although this is far less common, it’s important to note that you don’t have to be bitten to get rabies. For example, as a precautionary measure the World Health Organization recommends that people are immediately given a vaccination if a potentially rabid animal nibbles uncovered skin, or causes minor scratches or abrasions without bleeding.
Most mammals can carry the rabies virus, but the majority of cases result from being bitten by an infected dog. In 2003 it was recognised that some UK bats may carry a rabies-like virus. A bat handler died from this infection, which was probably acquired in Scotland. However, the types of bats found in the UK principally live off a diet of insects and are not “vampire” bats that live on blood.
Can I catch rabies from another person?
There have been no confirmed cases of rabies spreading between humans. The risk to other humans from a patient with rabies is considered to be negligible.
How big is the risk abroad?
Most cases of rabies occur in the developing world, particularly Africa and Asia. Half of all rabies cases occur in India. The countries associated with the biggest risk of rabies are:
- Dominican Republic
- El Salvador
- Sri Lanka
The HPA publishes a list that identifies the level of rabies risk by country.
Do I need a vaccination?
In the UK, the vaccine against rabies is not given routinely and is only recommended for people who are thought to be at high risk. These include laboratory workers who may be in contact with the rabies virus, people whose work includes handling bats or animals from abroad, and people whose travel activities may put them at increased risk. This will depend on the location they are visiting, the length of time they will be spending there and the availability of medical treatment should they get bitten.
If you aren’t sure whether to have a rabies vaccine before you travel, ask your GP or nurse as far in advance as possible to ensure you can receive a full course of the vaccine before you leave, if necessary. The vaccine, which consists of three injections over the course of a month, is not available on the NHS. It can be given by GPs and travel clinics on a private basis and costs £120–150.
Many of the regions where rabies is prevalent carry the risk of other diseases, such as malaria. It’s important to look into other diseases, vaccinations and risks ahead of travel. Appropriate travel health insurance is also advisable when going abroad, given the cost and complexity of arranging emergency healthcare in some countries.
Is rabies treatable?
A pre-exposure vaccination is an effective treatment for stopping people bitten by animals from becoming infected by rabies.
If someone is known to have been bitten by an animal suspected of having rabies, they will be given emergency treatment to stop the virus spreading beyond the site of the bite or scratch, even if they have had a vaccination ahead of travel. This treatment consists of cleaning the wound, administering a special preparation of antibodies which can help neutralise the virus and, if necessary, administering a course of the rabies vaccine. There are currently no antiviral drugs available outside of clinical trials to treat the rabies virus.
What is the best way to prevent rabies?
The HPA says it is essential to get health advice if you are travelling to countries where rabies is common or if you know you will be working with animals. Talk to your doctor or nurse about whether or not a rabies vaccine is appropriate before you travel.
Travellers to countries that are not rabies-free should avoid contact with cats, dogs and other animals wherever possible. It is also important to educate children about the dangers of stroking unknown animals. This is particularly true for animals that appear unusually tame, because this is an early sign of the rabies virus in animals. Children should be examined daily for cuts and scratches and should be made aware that being bitten by an animal is dangerous.
The World Health Organization estimates that 40% of people who are bitten by suspected rabid animals worldwide are children under the age of 15.
What should I do if I or someone in my family is bitten?
Anyone who is bitten, scratched or licked by a warm-blooded animal in a country that has rabies should immediately wash the wound or site of exposure with plenty of soap and water. Seek medical advice without delay, even if you have been previously vaccinated.
The HPA says that the rabies vaccine is extremely effective at preventing rabies in people who have been bitten, even when this is given some time after the bite. Those who do not get medical treatment while abroad should still seek it on returning to the UK.
Even in environments where rabies does not circulate, an animal bite or scratch still carries the risk of other infections such as tetanus and general bacterial infections. Read about treating animal bites for guidance on what to do in this situation.