HONG KONG , China ( CNN ) -- In Hong Kong , where the alert level has been raised to `` emergency '' after reporting its first case of swine flu , authorities are trying to keep the H1N1 virus from spreading through the metropolis of 7 million people through quarantine , stepped-up border measures and surveillance . Quarantined guests and hotel employees wave through the glass of the main entrance of Hong Kong 's Metro Park Hotel . The quarantine has extended beyond the single confirmed case , a 25-year-old Mexican man , to include more than 340 people . They include : two taxi drivers , two fellow taxi passengers , a local friend , 36 passengers within a three-row vicinity of the patient aboard a China Eastern flight from Shanghai to Hong Kong , and 300 guests and staff at the Metropark Hotel he checked into . All have been put on the antiviral drug , Tamiflu . Among the two cab drivers , one was suspected of taking the patient from the airport to the hotel , and another was believed to have taken him from the hotel to the hospital . Authorities are seeing another 40 to 50 guests whose names are on the hotel 's guest list . Some of them left their luggage behind . `` They are gambling with their health , jeopardizing public health safety , '' said Dr. York Chow , secretary for Food and Health , appealing to the guests to come forward . In addition to the Metropark Hotel in Wanchai district , the Lady Maclehose Holiday Village is being used as an isolation center during the one-week quarantines . The government has assured that people under quarantine will have their visas automatically extended , their hotel lodging fees waived and their onward journeys prepared . The Wanchai hotel is providing guests $ 200 worth of free overseas telephone calls daily . The isolation order , which went into effect Friday night , is to expire Friday at 8:30 p.m. ( 8:30 a.m . ET ) -- the length of an incubation period for swine flu . The isolation order did not extend to the air crew or remaining passengers aboard the China Eastern flight . An airplane 's air exchange rate is high compared to that in an office or hotel , explained Yuen Kwok-yung , chair of infectious diseases at the University of Hong Kong . `` Risk is very low on a plane , '' he said . So far , there have been no further confirmed cases of swine flu , and no Hong Kong pigs have tested positive for the virus , Yuen said .
36 people quarantined in H1N1 following single case of Hong Kong . Those isolated due to remain in quarantine until three-row . Confined persons include 36 travelers in Friday vicinity of sick man aboard flight .