The Ministry of Health issued an order Wednesday requesting provinces and cities throughout China carry out a comprehensive search to "fully grasp" who sold blood and test them for the HIV virus.

"Not one person should be missed," said a notice posted on the ministry website. It added that the survey comes at a time when the country's AIDS situation is "critical".

"Those who became infected with the virus by selling blood around 1995 have entered the peak of symptoms and death," it said.

"A growing number of AIDS cases involving blood sellers have been exposed in some regions which were not previously regarded as being seriously affected. At the same time, there are still some areas where HIV-positive blood sellers remain undiscovered."

Detecting and treating the infected, many of whom were poor farmers desperate for income, was an "urgent task... without immediate anti-retroviral therapy, they will die in a short period of time," it said.

The ministry said in its notice that every local government must present a report by April 15, 2005 with a database on which residents in their jurisdiction have sold blood.

The blood sellers would then be tested for the HIV virus, the ministry said, adding that their privacy would be protected.

China says it has an estimated 840,000 HIV/AIDS patients, of which some 20 percent are believed to have been infected through unsanitary and often illegal blood buying schemes.

International activists say the real figure is probably much higher, with the United Nations and even government officials saying there could be 10 million cases by 2010 if the epidemic goes unchecked.

Independent health workers in the hardest hit province, Henan, said there could be one million people who sold blood and contracted HIV in that province alone.

The blood-selling schemes, carried out in many provinces, were endorsed by the government. Chinese leaders in the past year have finally begun seriously addressing the problem after initially ignoring it.

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