The Department of Health's Centre for Health Protection on Thursday said it was investigating a second imported case of the potentially fatal Wuhan respiratory virus in Hong Kong, after preliminary tests produced a positive result. The virus has killed 17 people so far. The case involves a 56-year-old man. The Hong Kong resident travelled to Wuhan on January 10, the centre of the outbreak. He returned to Hong Kong by taking Air China flight CA-8279 from Wuhan to Shenzhen on Sunday before crossing the border at Lo Wu the same day by MTR. The man went down with a fever last Saturday but didn't have any respiratory symptoms. He went the Accident and Emergency Department at Prince of Wales Hospital the following day but hospitalisation was not required. He returned for follow-up on Tuesday and was admitted for isolation and management by the hospital as his fever hadn't subsided. He is now in stable condition and has been transferred to Princess Margaret Hospital for isolation and management. Meanwhile Hong Kong also awaiting results of a confirmatory test due on Thursday on another tourist who has tested positive for the Wuhan virus and is also isolated in Princess Margaret Hospital. Health officials are appealing to train passengers who sat near him to come forward so they can be quarantined. The man, 39, had arrived in Hong Kong with his family on Tuesday night, after taking train G1015 from Wuhan to Shenzhen North, then train G1015 to West Kowloon, arriving at 7.54pm. He had sat on seat 10D in carriage three on the journey to Shenzhen North; and on seat 2D on carriage two for his trip to Hong Kong. A new hotline, 2125 2122, has been set up for people who may have been on the same train, or think they may have come into close contact with the patient. People who sat in within two rows of the patient will be sent to quarantine camps for medical observation.