BEIJING, Jan. 19 (Xinhua) -- Chinese researchers have found that a robust antibody against the SARS corona virus remained in the bodies of recovered SARS patients for more than three years.

    "The discovery will help in the research of a SARS vaccine and help find the best therapy if SARS returns," said Li Taisheng, head of the research group, told Xinhua on Friday.

    The group of researchers from the Peking Union Medical College Hospital and the Chinese Academy of Medical Sciences has been following 30 recovered SARS patients since March 2003, when disease began to spread widely in China.

    Although the antibody declined moderately as time passed, it remained at a high level in the body for more than three years after the patients recovered, Li said.

    "We presume that recovered SARS patients could have long-term immunity from the disease," Li said.

    "More studies are needed to prove whether recovered SARS patients would have immunity from SARS for life," Li said.

    He said the neutralizing antibody was the most protective of all antibodies in preventing the SARS corona virus from invading healthy cells.

    Pinpointing the neutralizing antibody would help researchers develop a more effective SARS vaccine, Li added.

    The outbreak of SARS (severe acute respiratory syndrome) killed809 people worldwide in 2003. However, public memories of the disease are fading and many scientists have given up research on it.

    However, Chinese researchers have persisted.

    Li said, "There are still many problems with SARS that cannot be explained. For instance, where did the virus come from? If it was from the civet cat, why did it spread to humans suddenly at that time? And why did it disappear as suddenly as it came? Will SARS come again in the future?"

    The research will help the prevention and control of large-scale disease outbreaks like SARS in the future, Li added.