MODEL RELEASED. Common cold. Close-up of a mother wiping the nose of her baby who is suffering from a common cold. The common cold is caused by viruses transmitted in droplets which are breathed out by sufferers. Babies are vulnerable to these viruses as their immune system is not fully developed. Symptoms may include coughing, sneezing, chills, headache, listlessness, aching muscles and bones, and fever. Treatment includes keeping warm and rested, allowing the immune system to fight the infection. Medication can also be given to relieve the symptoms.