Visitors from Taiwan under scanner

‘‘Though no person has been quarantined so far but the screening will continue till the authorities are sure that there is no threat of the spread of the disease in the country,’’ said an official requesting anonymity.

Sources revealed that the Mumbai authorities had checked Moocha Shabir — a Mumbai resident working in Singapore — who had come in contact with Lt Col Chan at a conference in Singapore. ‘‘Shabir was quarantined on December 18 but tested negative for the SARS virus and has since returned to Singapore,’’ said the official.

Lt Col Chan was doing research on the disease and had come in contact with the virus while working on it in his laboratory. Chan had last worked on December 5 before leaving for Singapore to attend the conference on December 7. Upon his return from Singapore on December 10, he had developed fever two days later and was isolated on December 17.

‘‘About 90 people who came in contact with Chan have been quarantined in Singapore and Taiwan. Shabir was one of the persons he had met in Singapore,’’ the official said.