We don't know the scale of the problem in China, but we know it may soon be millions of people

Jeffrey Sachs

The government has recently begun to acknowledge the depth of the problem, he said - the most recent official figures showed a leap in the number of HIV-positive people.

But without much more effort to tackle the issue, China's huge migrant population and growing drug problem could combine to trigger a huge rise in infections.

That could hit tourism, eat into household savings as families have to buy expensive medicines, divert resources from other social services and decimate the working population.

"We don't know the scale of the problem in China, but we know it may soon be millions of people," he told the meeting.

"These are not subjects politicians want to talk about."

Face the facts

The Chinese government says that 850,000 people were infected at the end of 2001, up from the official tally of 600,000 midway through the year.

Ads pushing condom use to fight HIV are getting more common

But even this is an underestimate, say NGOs which believe the true figure is closer to 1.5 million.

Without prompt action, the UN warns that could reach 10 million - or almost one in 100 people - by 2010.

The situation is mirrored in other Asian countries such as India and Burma, Mr Sachs warned.

Moving around

For China, the big problem is the migrant population.

Economic shifts in recent years have driven millions of peasants off the land and into the cities, seeking casual work and living in poor conditions.

That has helped lead to a massive sex worker industry, Mr Sachs said - a combination which is the perfect scenario for the spread of HIV.

"The risk of multiple infection from Aids is very high now," he said, pointing to Africa's experience as an example of the potentially catastrophic results.

In South Africa, for instance, firms have cut investment as a result of soaring infection rates. Some have had to hire three people for one job, to take into account the likelihood of early death.

Care in the countryside

An important advance would be to improve health care in rural areas, Mr Sachs said.

A blood-selling scheme in central China infected thousands

Part of the reason for the higher profile of HIV in recent months was the scandal of widespread infection last year caused by blood banks in Henan province.

Cross-infection thanks to official mismanagement and corruption left thousands infected with HIV.

Mistrust of state health provision is consequently high.