Norovirus is a highly contagious stomach virus that causes diarrhea, vomiting, and stomach pain. It can lead to dehydration, especially in children, the elderly, and those with compromised immune systems, which can be dangerous. It takes very little norovirus particles to make you sick (less than would fit on the head of a pin!). Hand washing is the best way to prevent the spread of norovirus. Those affected should stay home from school or work until they have been without symptoms for 24 hours.
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