By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) - Did you ever notice how easily infections seem to spread in schools? In the case of a typical viral infection called the norovirus that can pop up in any school, it is estimated that an average of about one in four students and teachers can develop an illness with symptoms of nausea, vomiting, and diarrhea.

It is very common for a norovirus to cause acute outbreaks of this type.

In the US, the illness is usually spread by direct person to person contact. The contamination of a shared computer keyboard and mouse can contribute to spreading the illness. In this case, if you think about it, kids in school share many things, thus the easy spread.

The spread of norovirus during outbreaks can be reduced by following certain recommendations. Wash hands frequently and thoroughly, those who are ill should stay away from others, and shared surfaces and equipment should be disinfected.