'I can't carry heavy things and I often feel weak,' Yu said. 'I have to be careful with my diet and avoid eating anything oily, salty and hard. What's more, small ailments such as heatstroke, diarrhoea or a cold could be a serious test for me.'

China is fighting an uphill battle against the disease, which costs billions of yuan in medical bills each year. According to a national investigation in 2006, 7.18 per cent of the population aged from one to 59 on the mainland carries the virus, less than the nearly 10 per cent in the early 1990s. Among these 90 million people, about 30 million suffer from liver problems.

And the hepatitis C virus, which was not common on the mainland many years ago, now affects more than 30 million people, according to health figures.

Wang Hui, an infectious-disease expert from Shanghai Ruijin Hospital, said long-term treatment to curb the hepatitis virus was an economic burden for most patients.

It was not until 2009 that mainland authorities included mainstream hepatitis therapies - three orally-taken drugs and an injection - in the medical insurance scheme, but the coverage level varies in regions. In Shanghai, a patient still has to spend an average of 1,000 yuan a month for treatment to control hepatitis.

In rural areas, many farmers find insurance coverage difficult and struggle to get treatment. Yu said he had seen several peasants give up treatment because they did not have the money.

Dr Gao Zhiliang, a hepatitis specialist at the Third Affiliated Hospital of Sun Yat-sen University in Guangzhou, said he hoped that the insurance write-offs for hepatitis treatment could be raised to a higher level and that rules banning doctors from prescribing drugs to be used for more than two weeks could be revoked.

'Many of my patients are from outside Guangzhou so it's really inconvenient and costs them a lot to come here and get drugs every two weeks,' he said.

Wang said another difficulty for hepatitis patients is that they had to go to hospitals regularly for check-ups because many people developed a resistance to some drugs. Doctors had to change the treatment method.

She said a 2008 survey among hepatitis patients across the country showed that just one-third of them followed doctors' advice strictly in taking drugs. The rest quit the treatment for reasons ranging from expensive medicine bills to being too busy in their daily lives to be concerned about side effects.

Zhang Jianliang from the Shanghai Public Health Clinical Centre said halting the use of certain drugs could cause more problems, including to the liver.

Wang said that without the appropriate treatment, 12 to 25 per cent of hepatitis B patients would develop cirrhosis of the liver within five years. Six to 15 per cent with that problem would end up with liver cancer in the next five years. Zhang said a bigger proportion of hepatitis C patients would get cirrhosis, and much faster.

Since the mid-1990s the mainland has provided a free hepatitis B vaccine to newborns. As a result, less than 1 per cent of children under five contract the virus. Doctors want the government to extend the free vaccine to all infants, including those in remote rural hospitals and those born in violation of the rigorous one-child policy.

Apart from big medical bills and lengthy treatment, hepatitis patients on the mainland face a stigma in society even though screening for hepatitis B was abandoned for civil service recruitment two years ago.

The patient Yu said his situation was not so overwhelming as he had retired. But he worried his daughter would contract the disease because 'she was still young and if she gets that virus her friends and colleagues will discriminate against her'.

He plans to keep his condition secret from friends and relatives. 'If they knew I think they would be disturbed and hesitate to invite me to join their gatherings or dinners.'