Hepatitis E is a virus that can infect humans and cause inflammation of the liver (hepatitis). Hepatitis E infection usually produces only mild disease. In rare cases, however, it can prove fatal, particularly in pregnant women. Disease does not usually lead to chronic hepatitis or to a carrier state.
Symptoms of hepatitis E include yellowing of the skin and eyes (jaundice), darkening of the urine and pale stools, which may or may not be accompanied by tiredness, fever, nausea, vomiting, abdominal pain and loss of appetite. The disease usually clears within one to four weeks. A blood test is required to confirm the diagnosis.
Hepatitis E has historically been seen as a disease associated with travel to countries where it occurs more commonly in the population - in regions where sanitation may be poor, such as in Asia, Africa and Central America. However, there have been increasingly frequent reports of cases from industrialised countries involving patients who have not travelled abroad. Hepatitis E figures may be underestimates since many laboratories do not routinely test for the virus.
It is believed that hepatitis E infection associated with foreign travel is usually acquired from consuming contaminated food and water. The source of contamination is faeces shed from other infected people (or infected animals) - hence the importance of thorough hand washing after using the toilet.
Shellfish were implicated as the potential source of infection in an outbreak among UK passengers on a cruise ship touring the world. In another study patients with non-travel associated hepatitis E were infected by the hepatitis E virus that is carried by British pigs. Recently a study has implicated processed pork products as a cause of infection in England and Wales. It is possible therefore, that pigs might be a source of infection in people that acquire their infection in the United Kingdom. There could also be a source of infection that is common to both pigs and humans.
The average incubation period for hepatitis E is 40 days (range 15-60 days).
Most people will clear their infections naturally; no specific treatment is required. It is best for those infected to avoid alcohol during the course of their illness.
Pregnant and older people, those with weakened immune systems, and people with chronic liver disease might need closer observation for deterioration in liver function as they may experience more severe infection. Pregnant women should seek advice from their antenatal carer.
It is important to cook meat and meat products throughly and to practice good hygiene - always wash hands thoroughly before preparing or serving food; or before eating meals.
Currently, there is no licensed vaccine for hepatitis E. Advice to travellers to countries where sanitation may be poor. When travelling to countries with poor sanitation, it is advisable to boil all drinking water, including water used for brushing teeth. Bottled water may be used instead of boiled water. Avoid ice, poorly cooked shellfish, uncooked vegetables, salads, unpeeled fruit or unpasteurised milk.
During the first two weeks of illness, infected people should not prepare meals for others and, if possible, should limit contact with others, especially those who are pregnant or have pre-existing chronic liver disease.
Hands should be washed thoroughly with soap and warm water and then dried properly after contact with an infected person or their soiled articles. It is also important to wash hands after going to the toilet; before preparing or serving food; or before eating meals.
Further information and advice is available from: