MODEL RELEASED. Common cold. Young man blowing his nose with a tissue while suffering from a caused by a common cold. The common cold is a viral infection of the mucous membrane lining the nose and throat. The symptoms are sneezing, sore throat, headache and other discomfort. The common cold can be caused by over 200 known viruses. Most of these viruses belong to either the rhinovirus or coronavirus groups. They are transferred in droplets that are coughed or sneezed into the atmosphere by sufferers. Treatment includes keeping warm and rested, allowing the immune system to fight the infection. Medication can also be given to relieve the symptoms.