In the latest development of the mystery involving Jilin farmer Wen Congcheng, who was cleared of HIV/AIDS six years after first testing positive, local health officials have confirmed the authenticity of his HIV-negative test result.

"We do not have any doubts over Wen's HIV-negative results," said Meng Xiangdong, director of the AIDS/STD Research Institute of the Jilin Provincial Center of Disease Control and Prevention.

He said the Jilin City CDC gave Wen two HIV tests this year, the first one was in February and the second one quite recent, although he said he could not remember the exact date.

Many experts and doctors at both Jilin municipal and provincial CDCs were familiar with Wen as he used to go for HIV/AIDS control and prevention training after he tested positive in 2003.

"We plan to submit a report to the national CDC, and ask for help in deciding if the blood serum sample of the positive test result in 2003 really came from Wen," said Hou Xiang, director of the provincial CDC.

He said due to limited technological resources, no laboratory in Jilin Province was able to make the comparison.

Besides scientific research, the Chuanying District CDC and Jilin City CDC, where Wen tested HIV-positive in 2001 and 2003, should find the relevant nurses and doctors and try to recall what happened when Wen took the tests, said Hou.

The villagers who went with Wen to take the blood tests, especially those who were in the same line as him, should also be interviewed to see if there was any possible confusion of names, he said.

Meng said only HIV-positive blood samples need to be sent to the provincial CDC for confirmation, while negative test results from the city CDC do not need to be confirmed.