Hepatitis B vaccine and prevention

How hepatitis B spreads

There are two components to preventing hepatitis B:

• Prevention of transmission of the virus.

• Immunisation.

Hepatitis B virus (HBV) is spread by exposure to infected blood or body fluids. Methods of transmission include¹ :

• Vaginal or anal sexual intercourse.

• Blood-to-blood transmission:

  • Sharing of injection equipment by intravenous drug users.

  • Needlestick injuries.

  • Blood transfusion - now rare in the UK as blood products are screened.

• Infected tattoo equipment.

• Bites (rare).

• Perinatal transmission from mother to child.

The relative frequency of these methods of transmission varies from country to country. In low-risk countries such as the UK, transmission is most often through sexual contact or between injecting drug users.

Epidemiology

See the separate Hepatitis B article.

Prevention of hepatitis B transmission

Hepatitis B vaccine¹

• The vaccine contains hepatitis B surface antigen (HBsAg) adsorbed on to aluminium hydroxide adjuvant.

• A combined vaccine is available which provides protection against hepatitis A and hepatitis B.

• A hexavalent combination vaccine contains diphtheria/tetanus/acellular pertussis/inactivated polio vaccine/Haemophilus influenzae type b/hepatitis B (DTaP/IPV/Hib/HepB).

• Hepatitis B vaccines do not contain live organisms.

• The vaccine should be stored in a refrigerator at a temperature between 2°C and 8°C.

• Hepatitis B vaccine is safe and effective but should not be seen as an alternative to a strategy of prevention of transmission.
  

The hepatitis B vaccine is recommended as follows (see link to the Green Book for further details):

Routine childhood immunisation programme at 8, 12 and 16 weeks of age. It is important that premature infants have their immunisations at the appropriate chronological age (ie age since birth, not corrected).

Post-exposure immunisation is provided to infants born to hepatitis B infected mothers, identified through antenatal screening. An accelerated immunisation schedule at birth, 4 weeks and 8 weeks of age should be given.

Immediate post-exposure vaccination is used to prevent infection following exposure - for example, needlestick injuries.

Pre-exposure immunisation is used for individuals who are at increased risk of hepatitis B or complications of the disease because of their lifestyle, occupation, co-existing medical conditions or other factors:

• People who inject drugs, and their sexual partners, children, other household and close family contacts.

• Those who change sexual partners frequently, men who have sex with men, and male and female commercial sex workers.

• Sexual partners, close family and household contacts of a case or individual with chronic hepatitis B infection.

• Families adopting children from countries with a high or intermediate prevalence of hepatitis B.

• All short-term foster carers who receive emergency placements, and their families.
  Individuals receiving regular blood or blood products and their carers.

• Patients with chronic renal failure, or chronic liver disease.

• Inmates of custodial institutions.

• Individuals in residential accommodation for those with learning difficulties.

• People travelling to or going to reside in areas of high or intermediate prevalence.

• Individuals at occupational risk - eg, healthcare workers in the UK and overseas (including students and trainees), laboratory staff who handle material that may contain the virus, staff of residential and other accommodation for those with learning difficulties, other occupational risk groups, such as morticians and embalmers. Hepatitis B vaccination may also be considered for other groups such as the police and fire and rescue services.

Since 1982, over one billion doses of hepatitis B vaccine have been used worldwide. In many countries where 8% to 15% of children used to become chronically infected with hepatitis B, vaccination has reduced the rate of chronic infection to less than 1% among immunised children² . There is also evidence that the hepatitis B vaccine reduces the risk of developing hepatocellular carcinoma³ .

Hepatitis B vaccine schedule¹

• Dosage depends on age and brand. The manufacturer's guidance should be followed.

• Injections are given intramuscularly in the upper arm or anterolateral thigh. It should not be given into the buttock.

• The standard course of immunisation involves three injections at 0, 1 and 6 months.

• An accelerated course of 0, 1 and 2 months is possible - also for combined hepatitis A and B vaccines.

• Adults who need protection very quickly (eg, within 48 hours of exposure) can have a schedule of 0, 7 and 21 days. Adults and children considered at very high risk should also have an accelerated schedule. After an accelerated course, a booster at one year is recommended.

• Accelerated courses may also be best for drug abusers, as they are notoriously difficult to get to complete a course.

The duration of protection provided by the hepatitis B vaccine is still unknown but is believed to be at least 20 years⁴ .

The current UK recommendation is that those who have received a primary course of immunisation, including children vaccinated according to the routine childhood schedule and individuals at high risk of exposure, do not require a reinforcing dose of HepB-containing vaccine, except in the following categories:

• Healthcare workers (including students and trainees), who should be offered a single booster dose of vaccine, once only, around five years after primary immunisation.

• Patients with renal failure: any haemodialysis patient who is intending to visit countries with a high endemicity of hepatitis B and who have previously responded to the vaccine, particularly if they are to receive haemodialysis and have not received a booster in the last 12 months.

• At the time of a significant exposure.

Testing for hepatitis B surface antibody following vaccine¹

Testing for anti-HBs routinely is not recommended. It is only advised in certain groups:

• Those at risk of occupational exposure (particularly healthcare and laboratory workers):
  

  • Antibody titres should be checked one to four months after the completion of a primary course of vaccine.

  • Under the Control of Substances Hazardous to Health (COSHH) Regulations, individual workers have the right to know whether or not they have been protected.

  • This information allows appropriate decisions to be made concerning post-exposure prophylaxis (PEP) following known or suspected exposure to the virus.

  • Antibody responses to hepatitis B vaccine vary widely between individuals. 10-15% of adults fail to respond, or have a poor response.

  • It is preferable to achieve anti-HBs levels above 100 mIU/mL.

  • However, levels of 10 mIU/mL or more are generally accepted as enough to protect against infection.

  • Responders with anti-HBs levels greater than or equal to 100 mIU/mL do not require any further primary doses. Further assessment of antibody levels is then not indicated. They should then receive the reinforcing booster dose at five years.

  • Responders with anti-HBs levels of 10-100 mIU/mL should receive one additional dose of vaccine at that time. Following this, further assessment of antibody levels is not indicated. They should then receive the reinforcing dose at five years.

  • An antibody level below 10 mIU/mL is classified as a non-response to vaccine. In this situation, testing for markers of current or past infection is considered good clinical practice. A repeat course of vaccine is advised, followed by retesting one to four months after the second course. Those who still have anti-HBs levels below 10 mIU/mL and who have no markers of current or past infection will require hepatitis B immunoglobulin (HBIG) for protection in the event of exposure to the virus.

• People with chronic kidney disease on dialysis:

  • The role of immunological memory in patients with chronic kidney disease on renal dialysis is not clear. Protection may persist only as long as anti-HBs levels remain above 10 mIU/mL.

  • Antibody levels should be monitored annually and if they fall below 10 mIU/mL, a booster dose of vaccine should be given to patients who have previously responded to the vaccine.

  • Booster doses should also be offered to any haemodialysis patients who are intending to travel to high-risk countries if they have previously responded to the vaccine, especially if they are to receive haemodialysis and have not received a booster in the preceding 12 months.

Hepatitis B immunoglobulin¹

Specific hepatitis B immunoglobulin (HBIG) provides passive immunity.

As the vaccine alone is highly effective, the use of HBIG in addition to vaccine is only recommended in high-risk situations or in a known non-responder to vaccine. Whenever immediate protection is required, immunisation with the vaccine should be given. When necessary, HBIG should also be given at the same time as vaccine, ideally within 24 hours of vaccine, although it may still be considered up to a week after exposure.

Hepatitis B post-exposure treatment¹

PEP involves giving hepatitis B vaccine and possibly immunoglobulin too if required. PEP may be indicated even if the exposed person has received hepatitis B vaccine previously. It should be given ideally within 48 hours but no later than seven days after exposure. The vaccine is not needed for those people who have HbsAg or anti-HBs. However, the vaccine should not be delayed whilst awaiting blood test results.

Post-exposure vaccination is required in the following situations:

• Babies born to mothers who are chronic carriers of hepatitis B or to mothers who have had acute hepatitis B during pregnancy. (Full course of primary vaccine +/- HBIG.)

• Sexual contacts of people known to have acute hepatitis B. (Vaccine for sexual contacts at diagnosis, additional HBIG if unprotected contact occurred in the preceding week.)

• Accidental exposure from blood. For example, needlestick injuries, or contaminated blood coming into contact with open areas of skin, eyes or mouth. See the separate Needlestick Injury article. Vaccination schedule depends on degree of risk and vaccination/response history. If the site of exposure is a 'needlestick' injury, cut or abrasion, the site should be washed immediately with soap and water.

Neonatal hepatitis B screening and immunisation¹

Babies born to mothers infected with hepatitis B have a high risk of acquiring infection, which can be prevented by vaccination at birth. Therefore all women in the UK are screened during each pregnancy for hepatitis B. If a mother not previously booked for antenatal care presents in labour, she should have urgent hepatitis B screening, so that if needed the vaccine can be given to the infant within 24 hours of birth. Those women who are HbeAg-positive are particularly infectious.

Routine child hepatitis B immunisation

In August 2017, a routine vaccine programme was introduced for all infants born in the UK ⁵ :

• They will be offered a hexavalent (six components) vaccine (Hib-DTaP-hepatitis B-poliovirus).

• The new vaccine will replace the existing pentavalent (five component) vaccine to extend its 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 immunisation schedule, with the hexavalent vaccine replacing the vaccine previously given at 8, 12, and 16 weeks of age.

Hepatitis B vaccine complications¹

Adverse reactions to the vaccine are few and usually mild:

• There may be some soreness and erythema around the site. These are the most common reactions.

• Fatigue, malaise and influenza-like symptoms are rare.

• Rare associations with a Guillain-Barré-type syndrome and also multiple sclerosis have been reported but a causal relationship has not been substantiated.

HBIG is well tolerated. Reactions and side-effects are rare.

Contra-indications¹

The only contra-indication to hepatitis B vaccines is previous anaphylactic reaction to the vaccine or one of its components.

Vaccination should be postponed in the presence of acute illness with fever and systemic symptoms.

Pregnancy and breastfeeding are not contra-indications and there is no evidence of risk in giving hepatitis B vaccines in these situations.

Live vaccines should not be given within three months of administering HBIG, as it may interfere with development of immunity (other than yellow fever).