Colds are caused by a viral infection, with the first symptoms usually beginning two or three days after infection. Symptoms include a runny or stuffy nose; sneezing; sore throat; cough; sinus congestion; mild muscular aches; tiredness, and a headache.
Symptoms can last from two to 14 days, but most people recover within a week.
Children tend to get between three and eight colds a year, while adults average two to four a year.