BEIJING, May 2 (Xinhua) -- At least 113 people, who were on the same Mexico City-Shanghai flight with a Mexican national later diagnosed with influenza A/H1N1 in Hong Kong, are under quarantine, Chinese health authorities said Saturday.

    None of them have displayed any flu symptoms so far.

    The Mexican, a 25-year-old male, arrived in Shanghai Thursday aboard flight Aeromexico 098, which carried 176 people and 13 crewmembers.

    Of the passengers, 56 disembarked in Shanghai, 41 caught a connecting flight to Guangzhou, 17 transferred to Beijing, and two were refused entry to China.

    That accounts for 116 of the passengers, some of whom -- including the Mexican male -- flew on to Hong Kong, taking China Eastern Airlines flight MU505.

    Wu Fan, chief of Shanghai Municipal Center for Disease Control and Prevention, said all of the 48 passengers whose destinations were Shanghai were found. They are kept in a hotel for a week-long medical observation. Family members of these passengers were also told to maintain health observation at home.

    The entire crew remained in Shanghai and were put into quarantine, Wu confirmed.

    The health authorities in Shanghai are still looking for eight other passengers who also disembarked in Shanghai but only stay for a short period of time.

    Of the 17 who flew to Beijing, two left the city for Hebei and Jiangsu provinces and were put into quarantine by local disease control and prevention centers.

    The 15 whose final destination was Beijing were admitted by Beijing Ditan Hospital, Cheng Jun, deputy head of the hospital, told reporters Saturday.

    The health authorities of south China's Guangdong Province said they had only found 30 of the 41 passengers who caught a connecting flight to Guangzhou together with the Mexican patient.

    They are seeking the remaining 11 people, according to a notice issued by the Provincial Public Health Bureau Saturday morning.

    East China's Zhejiang and Jiangsu provinces said Friday they found 16 passengers who took the same flight AM098 with the Mexican national. These passengers were all quarantined.

    Health officials in Jiangsu reported they were notified by concerned departments in Beijing and Fujian Saturday about each passenger in the latter places who took the flight AM098 later traveled to Jiangsu. The two passengers were later found and were put under quarantine.

    Four more people in Jiangsu Saturday also reported to health authorities claiming they either took the same AM098 flight or MU505with the Mexican national.

    Relevant Chinese departments are still taking measures, including opening special telephone numbers to facilitate those who took the same flight AM098 with he Mexican national to report themselves.

    The Mexican male became Hong Kong's first confirmed case of influenza A/H1N1 infection Friday, prompting authorities to immediately raise the flu alert level from serious to the highest level of emergency.

    The patient checked into the Metropark Hotel in Wanchai, Hong Kong, on Thursday afternoon and developed flu symptoms such as lethargy, cough and a sore throat in the evening. The diagnosis was confirmed at a hospital, and the patient was put into quarantine, where he remained in stable condition Saturday.