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How contagious are colds?
The common cold virus is spread by:
- Breathing in droplets of fluid containing the virus, such as when someone sick sneezes or coughs without covering their mouth.
- Touching something handled by a sick person and then touching your mouth, nose or eyes. In general, a cold virus on an indoor surface can be infectious for over 24 hours.
Most people with a cold are contagious for about two weeks. It starts two to three days before the symptoms appear, and lasts until the symptoms go away. In the early stages a person is more contagious because the virus is reproducing in the nose and then coughed or sneezed out into the air.
Since it’s nearly impossible to isolate your sick child for the two weeks that they are contagious, it’s generally acceptable to allow them back to school or day care once their fever is gone and their symptoms have lessened.