New procedure capable of detecting virus earlier than current method

China will introduce RNA-based HIV testing at blood banks across the country to ensure earlier detection of the virus, safer blood supplies and fewer infections through transfusions, a top HIV/AIDS specialist said.

Wu Zunyou, head of the National Center for AIDS/STD Control and Prevention, told China Daily that the new test was domestically developed under government-funded science and technology projects.

"The RNA test is sensitive to the virus itself and is conclusive as early as 11 days after infection. Once the test is used nationwide, China will see a drop of 50 percent of HIV infections via blood transfusion," he said.

The RNA test looks for HIV-induced changes in RNA, a nucleic acid that is an essential component of all cells.

Currently, most blood banks use an antibody test, which looks for proteins in the body that battle HIV. It takes about 22 days for the human body to develop the antibody - and an accurate test result for HIV - after infection, experts said.

Despite the introduction of the improved test, "China won't even consider lifting a blood donation ban for gay men", whose HIV prevalence is about 5 percent and rising, compared with the 0.07 percent of the general population, he said.

About 10 people in the country get HIV via blood transfusions annually, a source with the National Health and Family Planning Commission said.

Wu said the RNA test, to be introduced nationwide next year, is "up to the standards of industrial countries". The test can detect the hepatitis B and C viruses as well, he said.

However, "zero risk of viral infection for blood transfusion doesn't exist so far," he added.

Internationally, the risk of contracting HIV via a blood transfusion is estimated at between 1 in 38,000 and 1 in 300,000 depending on the amount of blood.

To improve blood safety, "the government will invest heavily to replace antibody testing with the RNA-based genetic test for HIV across the country," Wu said.

RNA testing currently is limited to the large cities of Beijing, Shanghai, Nanjing, Hangzhou, and Guangzhou, he said.

RNA testing is more expensive than antibody testing. The RNA test costs about 60 yuan ($9.70), compared with the antibody test costing less than 20 yuan.

"It's worth the cost, given existing risks. The government is obliged to ensure a safe blood supply and public health," he said.

In a recent case, a 5-year-old girl named Maomao was diagnosed with HIV in Fuzhou, Fujian province, media reports said. Her parents tested negative for HIV.

Maomao had received a blood transfusion during heart surgery when she was 1.

An investigation into Maomao's case in ongoing. The possibility that she was infected via a blood transfusion can't be ruled out, the local health administration said.

According to Zhao Minggang, deputy director of the commission's medical administration bureau, "The window period is a challenge faced by all countries."

"People should be highly cautious about blood transfusions," Zhao said.