People dread the cold and flu season. Both diseases are viral and as such contagious. For both diseases people should assume they are contagious for as long as their symptoms last. For the cold this is usually 3-10 days, the flu 2-10 days. Cold symptoms include runny nose, sneezing, coughing, and sore throat. Flu symptoms are similar to the cold but can also include fever and body and muscle aches. People should be proactive in preventing the flu from spreading by washing hands frequently, and covering coughs and sneezes.
Medical News Today: How long are you contagious with a cold or flu for?