Rage et vaccin contre la rage

What is rabies?

Rabies is a disease caused by a virus. Almost everyone who develops rabies will die from it. Fortunately there is a vaccine to prevent it which is very effective.

Symptoms usually start 3-12 weeks after being bitten or scratched by an animal (usually a dog) carrying the rabies virus. However, symptoms may occur months or even years after a bite from an infected animal. The virus passes through the cut skin and travels (gradually) into the nervous system. After symptoms develop, most people die in less than two weeks.

Symptoms of rabies include:

• Initially mild symptoms of infection with a virus - headache, a raised temperature, and feeling sick (nausea) and generally unwell.

• A numb feeling in the skin around the area where the bite or scratch was.

• Being very agitated and not being able to sleep.

• Being very confused.

• Frothing at the mouth and having difficulty swallowing.

• A fear of water.

• Fits (convulsions).

• Muscle spasms.

• Not being able to move certain muscles (paralysis). This eventually includes not being able to use breathing muscles and it is this inability to breathe which results in death.

At present, the UK is virtually free of rabies. The strict regulations for imported animals help to keep rabies out of the UK. Animals coming into the UK must have proof they are clear of and immune to rabies. In the UK in recent years a very few people have died from rabies which they contracted from animal bites whilst abroad. There is a small risk from rabies in bats in the UK but not from other animals.

However, rabies is present in most of the rest of the world. Worldwide, there are more than 60,000 human cases each year. India has the highest number of cases of rabies and is classed as a high-risk area. Dogs are the main carriers of rabies. Foxes, cats, bats, monkeys, raccoons and skunks can also be affected. A bite from any of these animals from any country outside the UK should be taken very seriously.People who should be immunised against rabies include those who work with animals, and people who travel to remote areas where medical help is not available. The vaccine can also prevent rabies infection after a high-risk bite. Treatment with an anti-serum and vaccine works well if you receive them soon after being bitten.

People who are at risk of infection through their work

In the UK, people whose work puts them at risk of rabies may be entitled to a free vaccination - this would usually be arranged by their employer through occupational health. This group may include:

• Laboratory staff routinely working with rabies virus.

• Workers at Defra-authorised quarantine premises and carriers.

• Those who regularly handle bats, including on a voluntary basis.

• Veterinary and technical staff who, by reason of their employment, encounter enhanced risk.

People travelling

In addition, people travelling to areas where there is a high risk of rabies may be advised to have the rabies vaccination before travel. This is not available on the NHS and must be paid for. This includes:

Travellers to parts of the world at risk of rabies where medical treatment may not be available. For example:

• Animal control and wildlife workers, veterinary staff or zoologists who regularly work in areas where rabies is common.

• Travellers to areas where rabies is common and care for those who come into contact with rabies is likely to be in short supply.

• Travellers who are doing high-risk activities such as cycling or running.

• Those who are going to be in an area in which rabies is common, for more than one month.

Vaccines for travellers are available through GP surgeries, some pharmacies, and private travel clinics. Whether you need rabies vaccination will depend on:

• Which country you are visiting, and in some cases which part of the country.

• What you will be doing while you are there.

• How long you are staying.

• How old you are. (Children may be at higher risk, as they are more likely to pet stray animals.)

The rabies vaccine can be given:

• As a precaution, to people who have not been bitten but who are at risk of a bite from an animal with rabies. This is called pre-exposure prophylaxis.

• To people who have had a bite or scratch from an animal which might have rabies, to prevent them getting the rabies infection. This is called post-exposure prophylaxis.

• Both. Even if you have had the rabies vaccine as a precaution, if you are then bitten, you may need further doses to make sure you do not develop the disease. However, if you have had the vaccine beforehand, you will not need so many injections after a bite. If you have had the vaccine beforehand, you also have better protection against the rabies virus. It is important that you see someone who is qualified to make the risk assessment and decide on the need for further treatment, as well as to manage the wound.

Where on the body is the rabies vaccine given?

The rabies vaccine is usually given in the muscle at the top of your arm but it can also be given in the thigh.

Pre-exposure rabies vaccine

Prior exposure to rabies usually requires three doses of vaccine. The first injection, a second injection seven days later and a third injection 28 days after the first injection. The vaccine is very effective - almost 100%. That is, it will stop nearly everybody who has had it getting rabies if they are bitten by an animal with rabies.

The vaccine stimulates your body to make proteins called antibodies against the rabies virus. These antibodies protect you from rabies should you become infected with this virus.

Booster doses may be required after one year and then every 3-5 years for people whose work gives them a risk of contact with the rabies virus. People who are at a smaller risk by travelling again into areas with rabies may need a booster after ten years.

If your work puts you at risk of rabies, you may need a blood test to confirm you are immune from rabies. This may need to be checked regularly and a booster dose of the vaccine given if the blood test shows you are not immune.

Post-exposure vaccination

If you have a bite or scratch from an animal thought to be at risk of rabies (or an animal known to have rabies), you will need a course of the rabies vaccine. This may be two or five further doses of the injection. How many doses you need depends on how high a risk of rabies you have. This will in turn depend on:

• Which country you were in when you were bitten and how high the risk is there.

• What is known about the animal which gave you the injury (for example, which species of animal, if it is known to have rabies, if it has had rabies vaccinations).

• How bad the injury is and where it is.

• Whether you have had the pre-exposure injections or not.

These injections are available on the NHS. You will have them over a week (2-injection course) or a month (5-injection course). If you have not previously had the pre-exposure rabies vaccines, you will also have an injection of a substance called human rabies-specific immunoglobulin (HRIG).

This will protect you from rabies for a short time, while you wait for your vaccine to start to work. HRIG is injected either into your wound, or into the muscle in your upper leg.

• If you have an illness causing a high temperature (fever) it is best to postpone vaccination until after the illness.

• You should not have a booster if you have had a severe allergic reaction to this vaccine in the past.

• You should not have a rabies vaccination if you have had a severe allergic reaction to one of the components in the vaccine in the past. (For example, it contains traces of an antibiotic called neomycin, so you should not have it if you are severely allergic to neomycin.)

If you are pregnant or breast-feeding you may still be advised to have the vaccine if the risk of exposure to rabies is high.

There may be slight redness and swelling in the arm for 1-2 days, where the injection was given. Occasionally there are other side-effects such as a mild raised temperature, muscle aches or feeling sick (nausea). These soon pass without leaving any problems. Severe reactions are extremely rare but can include the neurological condition Guillain-Barré syndrome.

You should avoid any contact with wild or domestic animals when travelling abroad. If you are bitten by an animal in an at-risk country then:

• Wash the wound immediately with running water (and soap if possible) for at least five minutes.

• Disinfectant and a simple dressing may be applied to the wound.

• Seek medical care as soon as possible even if you have been previously immunised, as further treatment may be given to reduce the risk of infection.

You may need to have more doses of the vaccine. You may also need to have an injection of HRIG mentioned above. This will not usually be needed if you have already had a course of the vaccine, although if your immune system does not work properly (you are immunosuppressed) then you may need HRIG despite having had the vaccine.