A Beijing primary school was closed after seven students were confirmed as A/H1N1 flu cases Wednesday, the municipal health bureau announced late Wednesday.

Sixteen students at the Nanhu Zhongyuan Primary School in Chaoyang District were reported to have fever, and seven of them have been diagnosed with A/H1N1 flu, the bureau said.

A total of 154 students, teachers and parents who had close contact with the seven students are under observation.

Eighteen students were absent from class Monday and 12 of them, who are from four classes in two grades, developed fever.

Another four students were found ill the next day. Their testing results are yet to be released.

The health authorities are tracking where the students contracted the A/H1N1 virus, said Fang Laiying, director of the municipal health bureau.

"But the students are too young to remember clearly all the places they had been to before they got fever."

The flu outbreak forced the school to start the summer vacationa week ahead of schedule.

The primary school has 941 students and 78 teachers.

Beijing reported 21 confirmed A/H1N1 cases Wednesday, the largest in a day, bringing the total number in the Chinese capital to 155 as of 10 p.m. Wednesday.

(Xinhua News Agency July 2, 2009)