The World Health Organization has lifted travel warnings for Hong Kong and the neighboring province of Guangdong in China, as the threat of Severe Acute Respiratory Syndrome has eased in those areas. But another 55 cases of SARS were reported Friday in nearby Taiwan.

Meanwhile medical experts are working frantically to trace the origin of the deadly disease. As VOA-TV?s Melinda Smith reports, the latest research suggests the virus may have come from the civet cat.

In Guangdong province, civet cats are for sale at the local market. They are considered a delicacy for many people in southern China. But that could change. Yuen Kwok-Yung, the head of Hong Kong University?s Department of Microbiology, announced the findings of scientists who had tracked the virus for a month.

?Looking at the genetic information, it looks as if this coronavirus has been jumping from this civet into humans.?

Professor Yuen says the animals expel the virus in stools and respiratory secretions, and that its spread could be limited in the future by humans practicing better hygiene and regulating methods of slaughter.

Despite the lifting of travel warnings to Hong Kong, the former British colony still has the second highest rate of SARS infections outside of mainland China.

A quarantine was placed on this housing complex when at least 11 cases were diagnosed in just one part of the building. On Friday a team of nurses went through the complex, checking temperatures of the occupants.

As more cases were diagnosed in Taiwan, an American doctor from the U.S. Centers for Disease Control left the country Friday after developing a fever and cough, which are common symptoms of SARS. Doctor Chesley Richards, Jr. had been working with health officials in Taiwan to track down the disease. He had been staying at the Sheraton Taipei Hotel, which was sealed off immediately after he became ill.