School district officials raised to 70 the number of students afflicted by vomiting and diarrhea at Lake Harriet  Community School's lower campus from an apparent norovirus that resembles what used to be called stomach flu.
District spokeswoman Rachel Hicks announced the new total Friday afternoon after the district earlier reported 25 affected students at the southwest Minneapolis school which contains students from kindergarten to third grade.
Stool samples are being collected from some of those suffering the symptoms for analysis by the Minnesota Department of Health that will determine the specific strain of virus. The school is also undergoing a disinfection in common areas. 
Health workers from three agencies areinvolved. They've ruled out food-borne sources for the virus and also said it is not the respiratory sickness that more properly is known as influenza, according to Bill Belknap, a Hennepin County public health spokesman.
Principal Jan Parrish asked families in a voicemail to keep students home for 24 hours after their last episode of vomiting or diarrhea. She said the symptoms appear consistent with gastrointestinal rather than the respiratory flu.
The school has instituted stepped-up cleaning, including disinfecting all tables and chairs in the cafeteria and classrooms, restricting to teachers rather than students the job of passing out communal snacks, and suspending the use of self-service food bars for school breakfast and lunch. It is also redoubling hand-washing promotion.
The district said that no other schools appear to be affected so far, which also reduces the chances that school meals are a source for the illness. The school at 4030 Chowen Av. S. enrolled 320 students as of October.