An outspoken health expert, known for exposing the SARS cover-up in 2003, claims a mysterious infectious condition dubbed "negative AIDS" is more than a mental health problem, citing an independent study he led.

Zhong Nanshan told the Guangzhou-based New Express Daily: "The condition was not simply caused by mental problems," adding more information will be publicized soon at a coming seminar.

He also revealed that most of the alleged sufferers involved in his study suffered reactive arthritis.

His remarks appear to contradict the findings of a government investigation led by the Ministry of Health.

In mid April, the ministry dismissed media reports on the existence of the so called "negative AIDS" virus citing results from their probe.

Wu Zunyou, an AIDS expert with Chinese Center for Disease Control and Prevention said no new virus have been found among the alleged sufferers and they were most likely just suffering from a mental health problem called AIDS phobia.

Starting in 2009, media reports stated that sufferers display AIDS-like symptoms, including swollen lymph glands and bleeding under the skin, but repeatedly test negative for HIV.

In response, Zeng Guang, chief epidemiologist at the Chinese Center for Disease Control and Prevention, held the country's first government-initiated study of the issue, which involved experts in infectious diseases and mental health professionals.

A total of 59 sufferers were interviewed and examined, the report said.

Many of the people with the condition were engaging in high-risk behavior and had a strong fear of contracting AIDS/HIV, according to Zeng.

"The conclusion was reached that there was no such thing as a new AIDS-like virus or so-called negative AIDS," he said.