Hepatitis B (HBV), a serious liver infection, is often only diagnosed in the later stages, when patients start seeking medical help for advanced liver problems.

Up to 6 per cent of the population in Singapore are hepatitis B carriers, with many being unaware of their condition. 

Hepatitis B (HBV) infection often goes undiagnosed until patients seek medical help for advanced liver problems.

Hepatitis B is a serious infection of the liver caused by the hepatitis B or hep B virus (HBV).

If your immune system is unable to clear a hepatitis B infection within six months, it can lead to chronic hepatitis B (permanent liver inflammation).

Over time, serious complications can include liver cirrhosis (permanent liver scarring and shrinking), liver failure and liver cancer.

In fact, hepatitis B carriers are 200 times more likely to develop liver cancer than non-carriers.

In Singapore, liver cancer is the fifth most common cancer in men and third most common cancer in women, according to the Singapore Cancer Registry Annual Report 2022.

Unfortunately, a large number of cases are diagnosed at a late stage, when the patient has only a few months left to live.

“Early detection is critical to prevent progression to irreversible liver damage or liver cancer,” says Clinical Assistant Professor Rajneesh Kumar, Senior Consultant, Department of Gastroenterology and Hepatology, Singapore General Hospital (SGH), a member of the SingHealth group.

You cannot catch the hep B virus through hugs or casual contact with an infected person. Neither can the virus spread through coughing, sneezing or sharing eating utensils.

However, hepatitis B infection can spread through:

• 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 is best prevented by vaccination. The following groups who are at highest risk for contracting hepatitis B should be vaccinated:

• Individuals requiring repeated transfusions of blood and blood products.
  
  
• Patients who have natural or acquired immune deficiency e.g. HIV, or cancer patients.
  
  
• Patients with kidney failure who require dialysis.
  
  
• Healthcare workers.
  
  
• Intravenous drug abusers, homosexuals and commercial sex workers.
  
  
• Individuals living in areas where the prevalence of chronic hepatitis B is high e.g. Southeast Asia.
  
  
• Offspring of women who are hepatitis B carriers.
  
  
• Spouses and other sexual contacts of hepatitis B carriers.
  
  
• Laboratory workers dealing with blood or serum samples.

Side-effects of vaccines are rare and include local soreness at the injection site, mild fever, malaise but extremely infrequently may cause swelling of the lymph nodes (glands in the neck, groin, armpits), and abnormalities of the nervous system.

The vaccine is administered at time 0,1 and 6 months. However, before one gets vaccinated, one should check oneself for the immune status.

Only those who are non-immune to hepatitis B and not carriers should be vaccinated.

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.

3 Phases for chronic hepatitis b carriers

A chronic hepatitis B carrier goes through 3 phases, especially if the infection is acquired at birth. This is the usual scenario amongst carriers in Singapore:

1. High viral replicative ( immune-tolerant ) phase 
   The first phase is usually seen in patients less than 20 year old. There is rapid viral replication but the patient is well and has no symptoms. Blood tests and liver samples indicate minimal liver inflammation.
   
   
2. Low viral replicative (immune-elimination ) phase 
   The second phase occurs in patients between 20 to 40 years old. In this phase, the body's immune system attempts to rid itself of the hepatitis B virus, and this is reflected by abnormal blood tests that indicates active liver inflammation.
   
   The carrier may complain of lethargy. Occasionally, if this phase occurs in older patients, especially if more than 60 years, the clinical course is more serious and can cause severe liver dysfunction and death.
   
   
3. Non-replicative ( latent infection ) phase 
   The third phase occurs in carriers above the age of 40 years. This phase is characterised by the continuous presence of the hepatitis B virus with a low replicative rate.
   
   There may be however, evidence of liver damage which later progresses on to liver cancer. The patient in this last phase may present for the first time with swelling of legs and abdomen, progressive mental deterioration and vomiting or passing out of blood in the stools.