Wednesday, August 20, 2008

Implications of Hepatitis Infection

Hepatitis A

Hepatitis A is always self limiting. Even without any treatment, the infection will always resolve and the virus will be cleared. In otherwise healthy individuals it hardly ever threatens life and will not result in any serious long term complications or residual effect. There is no carrier state for Hepatitis A. Once the individual recovers from the infection, he can no longer infect another individual and should be immune to a subsequent infection.

Hepatitis B and C

Hepatitis B and C infections are very different from Hepatitis A. A person who gets infected can either clear the virus or become permanently infected. This latter group of individuals becomes “carriers” of the virus. These asymptomatic carriers can then potentially infect others. In Hepatitis B, the risk of becoming a carrier is dependant on the age at which the infection occurs. The younger the individual at the time of infection, the higher the risk of becoming a carrier. If infected at birth, the risk of becoming a carrier is almost 100%. If infected as an adult, only 10-20% will become carriers. For Hepatitis C, almost all infected individuals will become carriers.

Carriers of Hepatitis B and C are at risk of developing complications of the disease. In the initial stages, they are usually completely asymptomatic. Only when severe liver damage has already occurred will they feel unwell. Progression is very slow and complications with symptoms become apparent only after many years to even decades after the initial infection. These complications include liver hardening (cirrhosis), liver failure and liver cancer. It is estimated that a Hepatitis B carrier is at 200-400 times the risk of developing liver cancer compared to a non carrier.

However these outcomes are not inevitable and it is only with further tests that we can stratify the risks for any individual carrier.

Diagnosis of Hepatitis

Blood test will be able to diagnose Hepatitis A, B, C infections and also identify carrier states for Hepatitis B and C. Early detection is important as it allows counseling, life style modifications and close follow up to detect complications in their earliest stages. It also alerts other close contacts and family members to undergo screening and, if needed, to get vaccinated against catching the infection.

Protection and Precautions

Vaccination is available for Hepatitis A and B. Protection is however never absolute. Despite being successfully “immunized”, infection can still occur if an exceptionally large load of virus is acquired. There is no vaccination for Hepatitis C.

For Hepatitis A, 2 vaccinations are required, spaced 6 months apart. Some degree of protection is already present 2 weeks after receiving the first injection but the full course will still require a second injection to be given 6 months later. Almost all individuals will develop protection and this is life long after the second injection. No further boosters are required. Individuals seeking vaccination before they travel to a high risk area should be vaccinated at least 2 weeks prior to departure. The second injection may be taken upon return at the scheduled time. Since it is acquired through eating and drinking contaminated food or water, the usual precautionary measures for all travelers with regard to food and water consumption will apply.

Hepatitis B immunization requires 3 injections to be administered over a period of about 6 months. It can be given at the same time as Hepatitis A vaccination. Not all individuals successfully develop immunity after vaccination. It is therefore advisable that a blood test is performed about a month after the 3rd injection to confirm successful immunization. Generally, for individuals with no high risk profile, no booster is needed once immunity is confirmed.

Conversely, for individuals who regularly come into contact with Hepatitis B carriers, regular 3-5 yearly immunity level checks are advisable. It is however still controversial if booster doses need to be given. As the transmission methods are similar, precautionary measures applicable to HIV infection would apply in casual sexual relationships. This is particularly so in high risk scenarios e.g. sexual contact with a commercial sex worker. In a monogamous spousal relationship, no special precautions are recommended as long as the partner is successfully immunized.


Hepatitis A infection is usually self-limiting and in most cases, requires no medical intervention.

In contrast, Hepatitis B and C are serious diseases and there is ongoing research for drug therapy. Several drugs are now available but none are perfect. Tests need to be performed to determine if an individual will require or benefit from treatment. A specialist needs to be consulted for this decision to be made. Treatment is expensive, often requires injections, usually takes several months to a year to complete and is often associated with many side effects.

Dr Cheong Wei Kuen
MBBS (Singapore), MRCP (UK), M Med (Int Med), FAMS (Gastroenterology)
Consultant Physician & Gastroenterologist
Mount Elizabeth Medical Centre
WK Cheong Gastrointestinal & Liver Specialists Pte Ltd