Infections transmitted in body fluids: Hepatitis (non A) (ILO/IMO Guidelines Appendix E B 16-19)

Impairment and risks

The risks of transmission of infection through body fluids while at sea because of living and working conditions are remote. Aspects of lifestyle: sexual relations and practices, the use of injected illicit drugs and the adequacy of infection control practices in clinical care determine transmission risks. Because of the form of transmission and consequent stigmatisation of those with such conditions the process of assessment and decision taking on fitness has to take account of legal and ethical as well as scientific information.
The scope for exposure while undertaking normal maritime duties is limited to the treatment of accidents where blood has been spilt. Normal precautions designed to prevent wound infection also ensure that those providing emergency treatment are at very low risk of becoming infected, should the casualty have an infection that is transmissible in body fluids.
In a proportion of those infected with non-A hepatitis there will be a period when liver damage is manifest as jaundice and this is often when the condition is first detected. In most cases following recovery there is no subsequent impairment but sometimes chronic liver disease occurs. The level of continuing infectivity varies. There is also a late risk of the development of cirrhosis and liver cancer. The commonest form, hepatitis B, is readily prevented by immunisation.

HEPATITIS B (and other forms of hepatitis, excluding hepatitis A)

Rationale and justification

• Hepatitis B is a viral infection that is transmitted in body fluids (blood, semen, vaginal secretions etc).It can be transmitted horizontally by sexual activity and by blood, both during injected drug misuse and from needlestick injuries in healthcare. Vertical transmission from mother to baby occurs. It is considerably more infectious than HIV.
• Infection is often sub-clinical but can present with lassitude and jaundice 1-6 months after infection. Rarely there may be acute liver failure.
• In 95 % of cases the infection resolves within six months with no subsequent risk of infection but with continuing serological evidence of exposure to the virus. This leads to lifelong immunity.
• In 5% of cases the immune system cannot clear the infection and the person becomes a chronic carrier. The infectivity is higher in those who are e antigen positive. Carrier status is more common when infection is in childhood.
• Continuing infection may be without symptoms. It can be associated with active liver disease leading to cirrhosis and to a later risk of hepatocellular carcinoma of the liver. Regular surveillance is required if chronic hepatitis is present.
• Continuing infection may be treated with alpha interferon and appropriate antiretroviral therapy.
• Hepatitis B can be prevented by immunisation and this is recommended for sexual partners of those with the disease as well as for those at risk of infection from body fluids. Passive immunisation with hepatitis B immunoglobulin may be used where there are shorter term risks from mother to baby,needlestick or sexual transmission.
• The incidence of hepatitis B is lowest in NW Europe, N America and Australasia. It is high in South East Asia and Africa. Higher rates are found among injected drug users, those who received blood products prior to routine screening and those with multiple sexual partners.
• There are a number of less common forms of viral hepatitis that are infectious via body fluids and have a broadly similar pattern of effects (hepatitis C, D etc.). About 50% of those infected with hepatitis C will become chronic carriers, needing follow up. Immunisation is not available. Hepatitis D is a co-infection or superinfection with hepatitis B. This only occurs in the presence of hepatitis B and so can be prevented by immunisation. It frequently leads to liver failure.

Clinical assessment and decision taking (all forms of viral hepatitis except hepatitis A)

Note: Blood tests for hepatitis antibodies or antigens and liver function tests only form part of the statutory medical examination in some developed countries there are clinical indications for doing them. Elsewhere they may be considered if there is a high incidence of non-a hepatitis.

Advice to seafarers

There is a reliable immunisation to protect against hepatitis B. This is recommended for all seafarers working outside national coastal waters. Seafarers should be made aware of the risks of infection from sexual contact, needle sharing during drug misuse, inadequate sterilisation – including in tattooing and in sub-standard medical treatment facilities.