Hepatitis A is an acute inflammation of the liver caused by infection with hepatitis A virus. It is spread through the " fecal-oral " route i.e. through by ingestion of food contaminated by faeculent material. The period between ingestion and manifestation of illness (incubation period) is 28 days.
 
Symptoms
 
Some infected patients may not suffer any illmess, especially children. Symptoms and signs include :
Fever
Loss of appetite and vomiting
Abdominal discomfort
Dark urine, yellowing of skin and eyes ( jaundice )
Tiredness
Most people recover in under 2 months, but in a few, the illness may persist up to 6 months. Some patients may experience a symptomatic relapse 2 - 3 months after the initial illness.
 
Hepatitis A is a self-limiting disease. However, in less than 1% of patients, largely in the elderly, the disease may progress to acute liver failure (fulminant hepatitis ) and death. Unlike hepatitis B and C, long term complications does not occur with the hepatitis A.
 
How is Hepatitis A transmitted?

Hepatitis A is prevalent in areas where there are poor sanitary conditions. Most infections are spread by food or drinks contaminated by faeculent materials, either through poor personal hygiene or by sewage eg. contaminated raw shell fish. Rarely hepatitis A can be transmitted by intravenous drug usage, blood products and amongst practising homosexual men
 
 
Hepatitis B virus ( HBV ) is the most common human hepatitis virus in Singapore. HBV infection and its chronic sequelae are major world-wide health problems. There are approximately 300 million chronic HBV carriers in the world, of whom 75% are found in the Asia Pacific region. It is estimated that between 25 to 50 percent of these carriers can expect to die prematurely, either as a result of chronic liver inflammation and liver failure (cirrhosis) or the development of liver cancer.
 
6% of the Singapore population are hepatitis B carriers. Most hepatitis B infection is acquired during birth and in early childhood. These infections are generally asymptomatic. These carriers remain well for long periods and are discovered incidentally during blood donation, health screening or screening prior to vaccination. While the number of acute hepatitis B has decreased over the years, largely as a consequence of universal vaccination and screening of blood donors, doctors still have to deal with problems of chronic liver inflammation, liver cirrhosis and cancer.
 
How is hepatitis B transmitted, and who are at a higher risk of acquiring the infection?
 
Transmitted through body secretions like blood, semen, saliva
Babies of hepatitis B carrier mothers are infected at the time of birth or soon after birth.
Transmission in childhood can occur through shared utensils like toothbrushes and razors.
Hepatitis B infections can be acquired through blood transfusions if the blood donor is not properly screened for the infection.
HBV infections can also be acquired through acupuncture, tattooing, ear piercing, manicures and dental treatment if non-sterile instruments are used.
Healthcare workers like doctors, dentists and nurses are at risk of finger-prick injuries which also transmit HBV infection.
Unprotected sex promotes HBV transmission. Therefore, individuals who indulge in a promiscuous lifestyle like commerical sex-workers and homosexuals are at a higher risk of HBV infection.
 
Hepatitis B virus in babies and adults

A baby who acquires the hepatitis B infection manifests a different course of illness from one who is infected in adulthood. Generally, an infection contracted at birth (from mother-to-child), does not manifest in any symptoms. Following such an infection the baby has a 90% chance of becoming a hepatitis B carrier, because they are unable to eliminate the virus from their bodies.
 
On the other hand, an individual who acquires the infection as an adult displays symptoms of "acute liver inflammation" (acute hepatitis B). Of these patients, 1% develop a very serious clinical course known as fulminant viral hepatitis B. These patients deteriorate very rapidly during the clinical course of the illness and may go into liver failure or even die. However, newer modalities of treatment like liver transplantation exist.
 
Symptoms
 
The symptoms of acute hepatitis B include:
Yellowing of skin and the 'whites' of the eyeball (sclera ) known as jaundice.
Joint pain
Rash which may be itchy
Fever
Pain over the right upper abdomen
Dark tea-coloured urine
Nausea, loss of appetite and vomiting
Treatment in the acute period of the illness is essentially symptomatic relief of symptoms like itch, nausea and vomiting. It is generally advisable for patients with severe symptoms or deep jaundice to be admitted to hospital for observation because of the potentially severe consequences (fulminant hepatitis ) which may prove to be fatal, albeit rarely. This enables rapid intervention, which may be lifesaving, to be instituted if required. The patient is advised bedrest, and avoidance of alcohol and traditional Chinese remedies which could exacerbate his condition.