The common cold most often is transmitted by direct contact with germs from the nose, mouth, or coughed or sneezed droplets from someone who is infected, usually by hand-to-hand contact. Virus particles are passed from one person's hand to another person's hand. The second person then touches his or her eyes or rubs his or her nose, spreading the virus there, where the virus can start a new infection. It is possible to become infected by touching a surface, such as a tabletop or doorknob that was recently touched by an infected person, and then touching your eyes or nose . These viruses also can be spread by inhaling particles from the air after an infected person has coughed or sneezed.
Usually about half of the family members of an infected person will become ill. Colds also are transmitted frequently in schools and day care facilities.
To avoid getting or spreading a cold, it helps to clean your hands often, carefully dispose of all used tissues, and avoid rubbing your eyes and nose. If possible, you should avoid close, prolonged exposure to people who have colds.
People who exercise regularly, especially those who exercise daily, have fewer colds per year than those who are less active.
Although medical therapies can improve the symptoms of the common cold, they do not prevent, cure or shorten the illness. Drink enough fluids, get plenty of rest, and treat your symptoms to keep yourself as comfortable as possible. Gargling warm salt water can soothe a sore throat. Inhaling steam may improve nasal congestion temporarily. Over-the-counter cold remedies that contain a decongestant will help to dry secretions and relieve congestion. These remedies may also relieve cough, if the cough is triggered by mucus in the throat. Antihistamines may improve the symptoms of runny nose and watery eyes, but they should be used with care because over-the-counter versions cause sedation. Over-the-counter cough suppressants do not have a proven benefit, but some people feel that they are helpful. It is important to keep in mind that antibiotics do not cure the common cold or shorten the length of time that symptoms last. Vitamin C, zinc and echinacea (a frequently used herbal therapy) have been widely rumored to decrease the likelihood of developing the common cold and to shorten symptoms, but no conclusive research has demonstrated that this is true.