They may be carriers of the hepatitis B virus and not even know it. Others may simply choose to ignore it.
In fact, 2.8 per cent of Singaporeans and permanent residents aged between 18 and 69 are carriers of hepatitis B, said Professor Lim Seng Gee, senior consultant from the Department of Gastroenterology & Hepatology at National University Hospital.
This translates to about 130,000 carriers, estimates Prof Lim, of which only about 30,000 go for regular check- ups and monitoring. Carriers generally do not show any symptoms of the disease, but chances of complications increase after the age of 40.
He revealed this to reporters during a media briefing yesterday, in the lead up to World Hepatitis Day, which takes place tomorrow. The figures were from a study published in the Singapore Medical Journal in 2005.
Prof Lim, who is also the president of the Asia Pacific Association for the Study of the Liver, said: "Up to 60 to 70 per cent of carriers here are not monitored or do not undergo treatment."
The ill-effects of hepatitis B and C - both inflammations of the liver - include cirrhosis, liver cancer, liver failure and even death, if left untreated.
Hepatitis B and C can be transmitted by blood and sexual intercourse.
Universal vaccination in Singapore against hepatitis B began for newborn babies in 1987.
As of last year, Singapore residents aged 24 and below are all vaccinated against hepatitis B.
Vaccination for hepatitis C, which is curable, has not been developed yet, despite efforts by researchers, said Prof Lim.
To mark World Hepatitis Day, the Singapore Hepatitis B Support Group will hold two events, at which doctors will stress the importance of testing and early detection.
The events will be held at the Nanyang Community Club (CC) in Jurong West and Ang Mo Kio CC from 1pm to 3pm tomorrow.
Mr Sng Fook Yuan, 50, considers himself lucky to have learnt that he was a hepatitis B virus carrier about two decades ago, through a routine health check-up.
Five years ago, the financial adviser started taking medication for another ailment and a routine check-up showed that it was increasing his risk of a complication due to hepatitis B. He immediately stopped the medication and his situation improved.
Mr Sng said: "When people tell me that regular check-ups for hepatitis are very troublesome, I tell them that it is not a problem. It is a solution."
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