Some Key Facts
- Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.
- The virus is transmitted through contact with the blood or other body fluids of an infected person.
- Two billion people worldwide have been infected with the virus and about 600 000 people die every year due to the consequences of hepatitis B.
- The hepatitis B virus is 50 to 100 times more infectious than HIV.
- Hepatitis B is an important occupational hazard for health workers.
- Hepatitis B is preventable with the currently available safe and effective vaccine
Besides alcohol consumption, a series of deadly infections that spread through water, food and even blood transfusion can cause hepatitis (liver infection).
The virus may be transmitted through saliva of the first eater to the second person sharing an apple, warn doctors. “Every month about 20 to 30 cases are detected in Pune in which people catch liver infection even though they do not consume alcohol. An equal number of people approach us suffering from liver problems due to consumption of alcohol and hepatitis B infection,” said senior gastroenterologist Parimal Lawate of Jehangir Hospital.
Hepatitis B virus can cause an acute illness with symptoms that last several weeks, including yellowing of the skin and eyes (jaundice), dark urine, extreme fatigue, nausea, vomiting and abdominal pain. Liver cancer caused by hepatitis B is among the first three causes of death from cancer in men, and a major cause of cancer in women in this region.
Hepatitis B virus is transmitted between people by direct blood-to-blood contact or semen and vaginal fluid of an infected person. Modes of transmission are the same as those for the human immunodeficiency virus (HIV), but the hepatitis B virus is 50 to 100 times more infectious. Unlike HIV, the hepatitis B virus can survive outside the body for at least seven days. During this time, the virus can still cause infection if it enters the body of a person who is not protected by the vaccine.
In developing countries, common modes of transmission are:
•Perinatal (from mother to baby at birth)
•Early childhood infections (inapparent infection through close interpersonal contact with infected household contacts)
•Unsafe injection practices
•Unsafe blood transfusions
•Unprotected sexual contact.
Most people do not experience any symptoms during the acute infection phase. However, some people have acute illness with symptoms that last several weeks, including yellowing of the skin and eyes (jaundice), dark urine, extreme fatigue, nausea, vomiting and abdominal pain.
In some people, the hepatitis B virus can also cause a chronic liver infection that can later develop into cirrhosis of the liver or liver cancer.
Who is at risk for chronic disease?
The likelihood that infection with the hepatitis B virus becomes chronic depends upon the age at which a person becomes infected. Young children who become infected with the hepatitis B virus are the most likely to develop chronic infections:
•90% of infants infected during the first year of life develop chronic infections;
•30–50% of children infected between one to four years of age develop chronic infections.
•25% of adults who become chronically infected during childhood die from hepatitis B-related liver cancer or cirrhosis;
•90% of healthy adults who are infected with the hepatitis B virus will recover and be completely rid of the virus within six months.
A number of blood tests are available to diagnose and monitor people with hepatitis B. They can be used to distinguish acute and chronic infections.
Laboratory diagnosis of hepatitis B infection centres on the detection of the hepatitis B surface antigen HBsAg. A positive test for the hepatitis B surface antigen (HBsAg) indicates that the person has an active infection (either acute or chronic). WHO recommends that all blood donations are tested for this marker to avoid transmission to recipients.
There is no specific treatment for acute hepatitis B. Care is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.
The hepatitis B vaccine is the mainstay of hepatitis B prevention. WHO recommends that all infants receive the hepatitis B vaccine.
The vaccine can be given as either three or four separate doses, as part of existing routine immunization schedules. In areas where mother-to-infant spread of the hepatitis B virus is common, the first dose of vaccine should be given as soon as possible after birth (i.e. within 24 hours).
The complete vaccine series induces protective antibody levels in more than 95% of infants, children and young adults. Protection lasts at least 20 years and is possibly lifelong.
References: WHO, HealthIndia.com, Times of India