School authorities in the greater Montreal region are scrambling to reassure parents about risks associated to a case of the H1N1 virus at an elementary school in Chateauguay.

More than half of the children at Mary Gardner School stayed at home Wednesday after word spread that a student was diagnosed with the flu virus.

The New Frontiers School Board has a pandemic plan in place and parents shouldn’t worry about sending their children to school even if a flu case was confirmed, said director general Wayne Goldthorpe.

The school has adopted the plan's second phase, and "we've also taken measures over and above the normal cleaning [routine]," by enforcing sanitization measures, Goldthorpe told CBC News.

Schools have stockpiled cleaning supplies, and installed hand sanitizers in all schools — and janitors have been trained in better disinfection techniques, he said.

That includes cleaning desk tops, locker doors and keyboards, in addition to other surfaces normally cleaned.

With all the attention given to H1N1, parents may be overly precautious, but it’s important to keep the risk in check, Goldthorpe added.

"We probably have more students with measles and other infectious diseases that nobody is reacting to," he said.

"You can take your child to McDonald’s and have him on the slide with some other child, or go to a soccer game, or a football game, and you can pick up these viruses anywhere," said Karin van Drofelaar, Mary Gardner's principal.

Children are being reminded every day to wash their hands, van Drofelaar said.