A local primary school in Putuo District suspended classes today for all its 240 first graders on the same campus after 52 of them and two teachers suffered fever and vomiting.

　　“At present, we suspect that their sickness was caused by virus passed on from one student who went to a wedding feast on Sunday as he was the first to show the symptoms, while some other guests on the banquet also had fever and vomited,” Sun Naxin, headmaster of the Wuning Road Primary School, told Shanghai Daily.

　　The incident happened at the First Wuning Village Campus of the school, with the first student vomiting on Tuesday.

　　Another 51 students, including 19 of his classmates and students of other classes, and two music teachers also fell sick in the following two days.

　　The school disinfected the whole campus today and required students to wash their hands disinfectant before entering, while all first graders are told to stay at home.

　　Food and drug administration staff have collected samples of food the students had taken in the previous days to carry out tests.

　　Both first and second graders on this campus will suspend classes tomorrow to prevent expanded infection and the school will decide whether to continue the suspension according to health condition of students.