Vaccino contro l'epatite B

The hepatitis B vaccine can also be used to prevent infection if, for example, you have had a needlestick injury and you are not immunised. Some people need blood tests to check if they are immune. See your practice nurse if you think you need this vaccine.

Che cos'è l'epatite B?

Hepatitis B is an infection caused by the hepatitis B virus. The infection mainly affects the liver. However, if you are infected, the virus is present in body fluids such as blood, saliva, semen and vaginal fluid. In the UK it is estimated that about 1 person in 200 to 1,000 is infected with the hepatitis B virus. It varies widely depending on the part of the UK studied. It is much more common in other countries. It is most common in sub-Saharan Africa and East Asia.

If you are infected with the hepatitis B virus, the initial symptoms can range from no symptoms at all to a severe illness. After this initial phase, in a number of cases the virus remains in the body long-term. These people are called carriers. Some carriers do not have any symptoms but can still pass on the virus to other people.

About 1 in 4 carriers eventually develop a serious liver disease such as cirrhosis. In some cases liver cancer develops after a number of years. See the separate leaflet called Hepatitis B for more details of the disease.

If you are pregnant and are infected with the hepatitis B virus, you can pass it on to your baby as the baby is being born. Vaccinations for the baby can prevent this happening. So all pregnant women in the UK are offered testing for hepatitis B during each pregnancy. If the test is positive, the baby can be protected.

The hepatitis B virus is passed from person to person in one of these ways:

• Blood-to-blood contact. For example, drug users sharing needles or other equipment which may be contaminated with infected blood. (Blood used for transfusion is now screened for hepatitis B virus.) Healthcare workers can be infected through accidental needlestick injuries.

• Avere unprotected sex with an infected person.

• An infected mother passing it to her baby.

• Un human bite from an infected person. This is very rare.

Some people travelling abroad are advised to have hepatitis B immunisation in certain circumstances - for instance, for repeated visits, long stays or if you are having medical treatment while abroad.

Anyone who is at increased risk of being infected with the hepatitis B virus should consider being immunised. This includes:

• Workers who are likely to come into contact with blood products, or are at increased risk of needlestick injuries, assault, etc. For example:

  • Nurses.

  • Doctors.

  • Dentists.

  • Medical laboratory workers.

  • Cleaners in healthcare settings.

  • Morticians.

  • Prison wardens.

  • Police officers and fire and rescue workers.

  • Staff at daycare or residential centres for people with learning disabilities where there is a risk of scratching or biting by residents.

• People who inject street drugs. Also:

  • Their sexual partners.

  • The people they live with.

  • Their children.

• People who change sexual partners frequently (in particular, sex workers).

• People who live in close contact with someone infected with hepatitis B. (You cannot catch hepatitis B from touching people or normal social contact. However, close regular contacts are best immunised.)

• People who regularly receive blood transfusions (for example, people with haemophilia).

• People with certain kidney or liver diseases.

• People who live in residential accommodation for those with learning difficulties. People who attend day centres for people with learning difficulties may also be offered vaccination.

• Families adopting children from countries with a higher risk of hepatitis B, when the hepatitis B status of the child is unknown. (It is, however, advisable for the child to be tested for hepatitis B.)

• Foster carers or if you live with foster children.

• Prison inmates. Vaccination against hepatitis B is now recommended for all prisoners in the UK.

• Travellers to countries where hepatitis B is common. In particular, those who place themselves at risk when abroad. The risk behaviour includes sexual activity, injecting drug use, undertaking relief work and/or participating in contact sports. Also, if you may need a medical or dental procedure in these countries and the procedure may not be done with sterile equipment.

• Babies who are born to infected mothers.

You need three doses of the vaccine for full protection. The second dose is usually given one month after the first dose. The third dose is given five months after the second dose.

One to four months after the third dose you may need to have a blood test. You may need one if you are at risk of infection at work, especially as a healthcare or laboratory worker or if you have certain kidney diseases. Your doctor will be able to advise you if you need a blood test. This checks if your body has made proteins to protect you (antibodies) against the hepatitis B virus. If you have, you will not be able to get it (ie you are immune.)

You may then need a booster dose five years later. There is no need for a blood test before or after this.

The schedule is the same for the combined hepatitis A and B vaccine which is also available.

Routine immunisation schedule

From 2017 all infants born in the UK have been routinely offered a six-component vaccine (Hib-DTaP-hepatitis B-poliovirus). The new vaccine will replace the existing five-component vaccine to also give protection against hepatitis B virus (HBV) in addition to diphtheria, tetanus, pertussis, poliomyelitis, and Haemophilus influenzae type b disease. There will not be any change to the timing of the routine childhood vaccination schedule, with the hexavalent (6-component) vaccine replacing the vaccine previously given at 8, 12, and 16 weeks of age.

A schedule of giving three doses more quickly than usual may be used in some situations. That is, three doses with each dose a month apart. An even quicker schedule is also sometimes used. That is, the second dose given seven days after the first and the third dose given 21 days after the first.

These rapid schedules may be used if you are at very high risk of infection and need to be immune as soon as possible. For example, if you are soon to travel abroad, are new to prison or are sharing needles to inject drugs. However, a more rapid schedule may not be as effective for long-term immunity unless a fourth dose is given 12 months after the first dose. Your doctor will advise on the best schedule for your circumstances.

Side-effects are uncommon. Occasionally, some people develop soreness and redness at the injection site. Rarely, some people develop a mild high temperature (fever) and a flu-like illness for a few days after the injection.

Seek medical attention as soon as possible if you have been at risk from a possible source of infection and you are not immunised. For example, if you have a needlestick injury or have been bitten by someone who may have hepatitis B.

You should have an injection of immunoglobulin as soon as possible. This is an injection which contains antibodies against the virus. It gives short-term protection. You should also start a course of vaccination. The hepatitis B vaccine is very effective at preventing infection if given shortly after contact with hepatitis B.

Even if you have had the hepatitis B vaccine and are at risk of infection (for example, by having unprotected sex or sharing contaminated needles), you should ask your doctor for advice. You may be advised to have a booster vaccine or even an injection of immunoglobulin.

Babies who are born to infected mothers should have an injection of immunoglobulin as soon as possible after they are born. They should also be immunised. The first dose of vaccine is given within the first day after birth. This is followed by three further doses at 1 month, 2 months and 12 months of age. At 12 months, immunised babies have a blood test to check that the vaccine has worked.

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

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

• The vaccine may be given if you are pregnant or breast-feeding and vaccination against hepatitis B is necessary.