The local disease control center reported the situation to the municipal health bureau of Xi'an, which immediately dispatched officials to the site.
All those who were ill were sent home as soon as they felt sick and none were hospitalized as their symptoms were slight.
The school of 727 students was closed as of April 14 and classes resumed on April 22. No new cases have been found since at the school.
Speaking at a press conference after meeting with Chinese Health Ministry officials on the country's preparations in the event of a swine flu outbreak, Troedsson acknowledged appropriate actions Chinese authorities had taken in isolating students at home and closing the school. He also praised the openness and transparency of the Chinese government in reporting avian influenza cases to the WHO.
Shanghai stipulated nine measures Tuesday, including 24-hour monitoring by officials of the entry-exit inspection and quarantine bureau of arriving passengers and transport from Mexico, and arranging special paths for passengers coming from swine-flu countries for body temperature tests, said Xu Chaozhe, vice head of the bureau.
Those with high temperatures would be further examined and even sent to designated hospitals according to test results.
Shanghai airport receives about 35 flights from the United States and two from Mexico everyday, bringing about 7,200 people.
Jiang Hao, an inspector with the border checkpoint in Nanjing, capital of neighboring province of Jiangsu, which has adopted similar surveillance, said, "We will ask passengers from Mexico, the United States and other countries hit by the epidemic to take temperature tests upon arrival. We ourselves also attend regular training courses about swine flu and take measures to prevent the disease."
The island province of Hainan, situated off the south China coast, is on high alert for the flu. Two local hospitals have been designated to treat suspected cases.
