Antibiotics do not cure most colds, coughs, sore throats or runny noses, and they are ineffective against influenza. But to Mr Li and hundreds of millions of farmers, migrant workers and low-income city residents - who are beginning to join and benefit from China's rapidly growing medical insurance programme - antibiotics have become an affordable panacea and one that mainland hospitals are cashing in on.

Antibiotic abuse is expensive and damaging to public health. It has increased the frequency and ferocity of outbreaks of multidrug-resistant bacteria - like the notorious superbug methicillin-resistant Staphylococcus aureus, or MRSA - on the mainland. Medical experts have warned that an epidemic of antibiotic-resistant diseases will hit the world on an unprecedented scale if the mainland's medical welfare system turns out to be a breeding ground for the germs.

In just a few years, Beijing has tripled spending on programmes for rural and low-income urban residents. One programme, called the new co-operative medical scheme, is expected to cover the entire rural population by the end of this year.

According to the Ministry of Health, more than 700 million people will benefit from the programme, and some will have to pay only 10 yuan per year to receive government subsidies for up to 80 per cent of their medical bills.

Doctors use antibiotics - substances obtained from some bacteria to restrain or destroy other bacteria - partly because patients want them. Until 2004, antibiotics were officially called 'anti-germ' medicine, and regarded as a cure-all by people who considered all bacteria harmful.

Ministry data shows that, of the top 15 best-selling medicines on the mainland, 10 were antibiotics; 80 per cent of patients admitted to hospital were treated with antibiotics. The ministry said sales of antibiotics accounted for more than 50 per cent of the bills issued to patients.

Hospitals usually charge patients 20 times the factory price for antibiotics, according to Xinhua. As a result, patients who seek treatment for the common cold are often given prescriptions for drugs that can cost more than 200 yuan.

The result, says Goldman Sachs International researcher Zhang Ruifang in a 2006 study, is that the mainland has the highest level of antibiotic resistance in the world, followed by Kuwait and the United States.

Even by 2001, about 77 per cent of the most common mainland bacteria showed some resistance to antibiotics. The mainland has the fastest growth rate of resistance, with levels rising about 22 per cent from 1994 to 2000, compared with 6 per cent in the US over a similar period.

'MRSA is the biggest threat in China, where resistance among hospital-acquired infections reaches almost 90 per cent, the highest [among the reporting countries],' the Goldman Sachs report said.

Each year nearly 100,000 patients are directly killed by antibiotics overdoses on the mainland, and the problem, along with drug resistance, has attracted the attention of Beijing. In 2004, the health ministry issued a regulation to limit the clinical use of antibiotics, made some products prescription-only and changed the official translation of the medicine from 'anti-germ' to 'anti-life'.

The clinical regulation requires doctors to give antibiotic prescriptions to patients who really need them, but this is still more of a theory than a general practice because of technological limitations, according to Hu Bijie, director of the infection control department at Fudan University's medical school.

'To diagnose what causes a symptom, doctors need to take and cultivate samples from patients, a process that can take days - if not weeks. All of the work must be done by hand. No hospital or doctor is able to conduct a detailed personal diagnosis for every patient,' Professor Hu said.

'As a result, doctors resort to powerful antibiotics designed to eliminate a wide spectrum of known harmful bacteria. It sounds silly. But we really don't have a choice sometimes.'

The good news is that in 2003, Han Jian, now a principal investigator at the Hudson Alpha Institute for Biotechnology, developed revolutionary diagnostic equipment that completely automates the labour-intensive and time-consuming molecular identification process.

The technology, called Templex, allows a doctor to determine in a couple of hours whether a patient needs antibiotic treatment.

The Chinese Centre for Disease Control and Prevention, and provincial epidemic monitoring networks, quickly adopted the technology to identify victims of Sars or bird flu.

But when Dr Han tried to push the technology into mainland hospitals, few of them were interested. 'Here in China, the longer you stay in the hospital, the more money they make. So the hospital is not rewarding efficiency in the medical system.

'I discussed the problem with some government officials, including the health minister and deputy ministers. They said a huge social reform would be involved because, if you implement the technology in China, you need to work with the pharmaceutical companies that sell antibiotics; you need to work with the insurance company, because the value it generated needs to be redistributed in the value chain,' Dr Han said.

'The only way I can think of doing this in China is to amass a large amount of venture capital from people or the government, who would spend money to buy the pharmaceutical company, buy the insurance programme and buy the hospitals, so that diagnosis can be made correctly in the beginning.

'I want to do a social experiment. Give me a hospital, give me a pool of patients, let me use the technology and I will show you the results.'

Bugs in the system

According to a Goldman Sachs report, China has the highest incidence of antibiotic-resistant bacteria in the world

In 2001, the percentage of common bacteria found to have at least some resistance was 77%