Letters were sent home with students from two Ottawa elementary schools Friday afternoon after a cluster of flu cases health officials believe is the H1N1 virus.
The schools in question are Guardian Angels in Stittsville and St. Clare Catholic School in Orl�ans, where many students have been absent.
"We asked schools and daycares to report to us high rates of absenteeism," said Dr. Isra Levy, Ottawa's medical officer of health.
21 H1N1 cases have been confirmed in the capital region, including three more this week. None of the cases are serious.
Ontario is confirming 131 new cases of the swine flu since Wednesday, bringing the total number of cases in the province to 626.
With files from The Canadian Press
