The Ministry of Health said on May 10 no new or unknown viruses had been found in the country's self-proclaimed "HIV-Negative AIDS" group, and the cause of their AIDS-like symptoms have yet to be determined.

The conclusion was based on tests by domestic and overseas authoritative facilities, said ministry spokesman Deng Haihua.

The "HIV-Negative AIDS patients" said they displayed symptoms very similar to AIDS, such as swollen lymph nodes, subcutaneous bleeding, joint pain, fatigue, night sweating and loss of weight. They termed it "HIV-Negative AIDS," thinking they might have been suffering from a mutation of the AIDS virus, or a new unknown virus.

Citing the latest tests on 60 such "patients," Deng said no evidence suggested they were suffering from an infectious disease.

However, the tests found the Epstein-Barr virus (EBV), a very common virus of the herpes virus family, in 55 percent of the patients, according to Deng, who said further research needs to be conducted in order to determine whether the EBV is the cause of the group's symptoms.