World Hepatitis Day-28 July 2011
28 July 2011 marks the first official World Health Organization-supported World Hepatitis Day. Hepatitis kills more than one million people every year. Millions more suffer immediate sickness or long-term ill health. World Hepatitis Day provides an opportunity to recognise viral hepatitis as a major global health problem in order to advance prevention and control.
Hepatitis viruses A, B, C, D and E can cause acute and chronic infection and inflammation of the liver leading to cirrhosis and liver cancer. These viruses constitute a major global health risk with around 350 million people being chronically infected with hepatitis B and around 170 million people being chronically infected with hepatitis C. Today, more than 500 million persons worldwide are living with viral hepatitis and do not have adequate access to care—increasing their risk for premature death from liver cirrhosis and liver cancer.
Hepatitis A is the most common cause of acute viral hepatitis in many parts of the world including South Africa. The virus is endemic in southern Africa however the true burden of disease is unknown. Although infection in childhood is frequently mild, severe disease can occur in certain high risk groups and disease in adults is frequently associated with significant morbidity.1Localized and more widespread community and institutional outbreaks occur in South Africa and frequently raise challenges for control given limited resources.
In addition South Africa has a unique epidemiological pattern of disease with variation in rates of infection across different socio-economic groups and provinces. Outbreaks of hepatitis A have been described for centuries. Person to person spread is the most common method of transmission via the faecal-oral route. However infection may also result from exposure to a common vehicle such as faecally contaminated food or water.4 Transmission via blood products has been described but is infrequent. There is however increasing evidence that the viraemic phase of the illness is much longer than previously thought and adult patients may be viraemic for up to 30 days prior to the onset of symptoms.5 Infection is also transmitted through anal-oral sexual contact. Although the virus can be detected in saliva there is no evidence for transmission via this route.4
Symptoms
The symptoms of hepatitis A range from mild to severe, and can include fever, malaise, loss of appetite, diarrhoea, nausea, abdominal discomfort, dark-colored urine and jaundice (a yellowing of the skin and whites of the eyes). Not everyone who is infected will have all of the symptoms. Adults have signs and symptoms of illness more often than children, and the severity of disease and mortality increases in older age groups. Infected children under six years of age do not usually experience noticeable symptoms, and only 10% develop jaundice. Among older children and adults, infection usually causes more severe symptoms, with jaundice occurring in more than 70% of cases. Most people recover in several weeks – or sometimes months – without complications.
Who is at risk?
Anyone who has not had been infected previously or been vaccinated can contract hepatitis A. People who live in places with poor sanitation are at higher risk. In areas where the virus is widespread, most Hepatitis A infections occur during early childhood. Other risk factors for the virus include injecting drugs, living in a household with an infected person, or being a sexual partner of someone with acute Hepatitis A infection.
Transmission
Hepatitis is usually spread from person to person when an uninfected person ingests food or beverages that have been contaminated with the stool of a person with the virus. Bloodborne transmission of Hepatitis A occurs, but is much less common. Waterborne outbreaks, though infrequent, are usually associated with sewage-contaminated or inadequately treated water. Casual contact among people does not spread the virus.
Treatment
There is no specific treatment for hepatitis A. Recovery from symptoms following infection may be slow and take several weeks or months. Therapy is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.
Prevention
Improved sanitation and Hepatitis A immunization are the most effective ways to combat the disease.
Adequate supplies of safe-drinking water and proper disposal of sewage within communities, combined with personal hygiene practices, such as regular hand-washing, reduce the spread of Hepatitis A. Several hepatitis A vaccines are available internationally. All are similar in terms of how well they protect people from the virus and their side-effects. No vaccine is licensed for children younger than one year of age. Nearly 100% of people will develop protective levels of antibodies to the virus within one month after a single dose of the vaccine. Even after virus exposure, one dose of the vaccine within two weeks of contact with the virus has protective effects. Still, manufacturers recommend two vaccine doses to ensure longer-term protection of about 5 to 8 years after vaccination. Millions of people have been immunized with no serious adverse events. The vaccine can be given as part of regular childhood immunizations programmes and with vaccines commonly given for travel.