Liver of no return
Hepatitis B, with half a million carriers in this city, is a disease that haunts the medical and patient community. One in four sufferers dies from liver cancer, cirrhosis or other complications.
Spread through contact with the blood or body fluids of an infected person - such as from an infected mother to her baby at or after birth, and through unprotected sex with a carrier - the disease lacks symptoms. Coupled with drug resistance in some patients, prompt and effective treatment is difficult.
Thanks to the introduction of DNA testing by local hospitals this year, a ray of hope has been cast on the quest to increase survival rates.
According to Nancy Leung Wai-yee, chairwoman of AsiaHep Hong Kong, a non-profit organisation that aims to raise awareness of the disease, the introduction of the hepatitis B viral (HBV) DNA test by seven public hospital clusters could help reduce the number of lives lost to liver cancer. This is the second biggest cause of cancer deaths for men in Hong Kong.
The test measures the amount of hepatitis B virus present in a millilitre, or a drop, of blood. A high figure means the virus is active and the carrier has a high risk of having liver damage. Doctors can then switch to another medicine, or add a second drug if needed. A low amount means the virus is not present, or is present in such low numbers that it cannot be detected, which indicates the medicine is effective.
'It's a promising development,' says Leung. The test, which costs about HK$400, is done once every three to six months on patients taking hepatitis B medicine. From this year onwards, the Hospital Authority will fund a quota of about 36,000 such tests each year.
Leung says the DNA test is a big improvement on the conventional liver enzyme tests that are done to check the effectiveness of anti-viral treatment. 'Enzyme tests are cheap, costing less than a hundred dollars. But their readings can be irrational,' she explains.
Checking enzyme levels alone to see whether the virus is active or not can delay treatment, says Dr Vincent Leung King-sun, a consultant at United Christian Hospital. 'The levels of HBV DNA will rise before liver enzymes do in the presence of drug resistance,' he says. 'For a patient who develops drug resistance, the virus will replicate itself for a period of time.
'By the time the virus replication spirals out of control, the immune system will begin to attack liver cells. Damaged cells will release enzymes into the blood, pushing up readings. Some sufferers develop drug resistance after taking medicine for only a short time. By the time the enzyme readings shoot up, liver cells are already damaged.'
Nancy Leung says patients must take both enzyme and DNA tests so doctors can better monitor their condition.
There are 350 million hepatitis B carriers globally, and 75 per cent of them are Asians. Hong Kong Hep B Free Foundation and AsiaHep Hong Kong launched a series of activities on World Hepatitis Day (July 28). These included free medical tests to raise awareness.
According to the foundation, there are 500,000 hepatitis B carriers in the city. The infected can develop complications such as chronic hepatitis, encephalopathy (liver disease that causes confusion and excessive sleepiness), liver cancer and liver failure. A common complication - cirrhosis - can induce vomiting of blood and accumulation of fluid in the abdomen. This can predispose patients to potentially fatal peritonitis, where the membranes of the abdominal wall and organs get inflamed.
The spread of the disease in the city has fallen dramatically since 1988, when the government made it compulsory for newborn babies to be vaccinated. This reduced the newborn infection rate from about 10 per cent to 0.78 per cent. There were 70 to 80 new patients in 2009, or only one third of 1988's figure. Babies who are vaccinated against the virus enjoy protection for life. But those who were born before 1988 are still at risk of contracting the virus.
Nancy Leung says more than 10 per cent of people aged over 40 suffer from chronic hepatitis B infection.
Sin Chun-leung, 48, who has been battling the disease for 15 years, was forced to quit his job in horticulture six months ago due to his worsening condition.
In June, a PET scan showed two patches of white shadow on his liver - signs that could point to initial-stage liver cancer.
'There was no medicine to take when I was diagnosed with chronic hepatitis B 15 years ago. I was just advised to get more rest,' he says.
Sin joined a free clinical trial in Alice Ho Miu Ling Nethersole Hospital in 2003, but withdrew from the scheme a year later because his condition did not improve. He began to suffer severe complications, including peritonitis, last year. 'My stomach filled with water,' he says. 'It was so painful I couldn't walk. I feel like I am carrying a ticking time bomb. I am afraid that I won't be able to wake up after falling asleep.'
While there's no known cure for the disease, drugs are used to stop the progression of liver ailments. Lamivudine, which costs about HK$700 a month, was the standard treatment in the past. But 50 to 70 per cent of patients who use it for five years develop a resistance to it, says Nancy Leung.
A more potent drug, Entecavir, has been available since 2006, with only 1.2 per cent of patients developing drug resistance after using it for six years. Initially costing a hefty HK$3,000 a month, the cost is now down to HK$1,300. But the monthly medical expenses still put a heavy financial burden on patients.
Housewife Tsang Sui-sum, who was diagnosed with cirrhosis induced by hepatitis B virus in 1997, spent HK$50,000 for weekly injections of the anti-viral drug Pegylated interferon alpha 2a in 2005. 'In spite of the cost, a medical test in 2006 showed an increase in virus amount,' she says. She switched to Entecavir soon afterwards, and her last test in June showed a normal enzyme reading.
The availability of drugs and tests has given Tsang more hope of leading a healthy life. 'I felt very worried when I first got my diagnosis. I was afraid that I would succumb to the disease and be unable to take care of my daughters,' she says.
'The fact that I could take the DNA test regularly to help pre-empt a worsening of the condition made me feel relieved.'
Another new drug, Telbivudine, was approved by the US Food and Drug Administration in 2008. It was introduced in local hospitals this year. It is an efficient drug in the fight against the disease, says Nancy Leung. Although 11 per cent to 25 per cent of patients develop drug resistance after using it for two years, it is half the price of Entecavir.
So it is a much more affordable option - especially for patients in the public hospital system, of whom half have to bear the full cost of the drugs.
For all the new medical advances, Nancy Leung says prevention through vaccinations, regular check-ups, blood tests and follow-ups are key to fighting the disease.
A recent survey by the Hong Kong Hep B Free Foundation indicated a widespread lack of understanding of the disease. Of 2,000 people surveyed, 60 per cent had not been vaccinated, or did not know whether they had been vaccinated or not.
Only 70 per cent thought the disease was preventable. Forty per cent wrongly believed that the disease had obvious symptoms, and 30 per cent mistakenly thought that eating dinner together, using the same towel, sharing utensils and shaking hands with the virus carrier would infect them.
Clerical worker Chung Man-hong, who has cirrhosis induced by the hepatitis B virus, has kept his condition a secret from friends and colleagues for fear of being stigmatised. But what frightens him most is the insidious way the disease struck his family.
'We got ourselves tested shortly after the death of my grandma, who died of liver cancer in 2001,' he says. 'It turned out my mum, older brother and I are also afflicted with the virus. There were no symptoms at all. My grandma felt her stomach was a bit swollen. One month later, she died of liver cancer. That's why having medical check-ups is important.'
- There are 500,000 Hepatitis B carriers in Hong Kong
- 75 per cent of the 350 million global carriers are Asians
Avoid or contain
Lifestyle advice for hepatitis B carriers and non-carriers
Get a vaccination that involves three shots
Practice safe sex and use condoms
Do not share needles or personal grooming items like toothbrushes, razors and nail clippers that might be contaminated with blood
Make sure that all equipment used for body piercing and tattooing is sterile
Have a diet that is low in greasy foods, sugar and red meat
Get regular medical check-ups to monitor the state of your liver
Avoid alcohol if there is inflammation of the liver
Strengthen immunity against diseases through getting regular exercise and adequate sleep