2 Answers

When Am I Most Contagious?
Let's assume you're the one with the cold. During the two-week period when you're contagious, research indicates that you'll be most likely to transmit the cold virus when you're experiencing cold symptoms. The period when you're most contagious is when your symptoms are at their worst -- day 2 to day 4 of the cold. You'll become less contagious as the cold symptoms improve. http://cold.emedtv.com/common-cold/common-cold-contagious-period.html

How Long is a Cold Contagious?

A cold is typically most contagious the first 48-72 hours after symptoms begin, but can be contagious as long as symptoms persist. Be sure to sanitize common surfaces like phones, light switches, remotes and door knobs to avoid spreading th... Read More »

Source: http://answers.ask.com/Health/Diseases/how_long_is_a_cold_contagi...