Common Cold

An infection of the nose and throat that can be caused by many different viruses

  • More common in children
  • Gender, genetics, and lifestyle are not significant factors

There are at least 200 highly contagious viruses that are known to cause the common cold, including rhinoviruses, coronaviruses, and respiratory syncytial virus (RSV). These viruses are easily transmitted in the minute airborne droplets sprayed from the coughs or sneezes of infected people. In many cases, the viruses are also spread to the nose and throat by way of hand-to-hand contact with an infected person or by way of objects that have become contaminated with the virus.

Colds can occur at any time of the year, although they are more frequent in autumn and winter. In the UK, adults typically get between two and five colds a year and children get between seven and ten. Children are more susceptible to colds than adults because they have not yet developed immunity to the most common cold viruses and also because the viruses usually spread very quickly in communities such as nurseries and schools.

What are the symptoms?

The initial symptoms of a cold usually develop between 1 and 3 days after infection. Symptoms usually intensify over 24–48 hours, unlike those of influenza, which usually worsen rapidly over a few hours. If you have a cold, symptoms may include:

  • Frequent sneezing.

  • Runny nose with a clear watery discharge that later becomes thick and green coloured.

  • Mild fever and headache.

  • Sore throat and, sometimes, a cough.

Spreading the cold virus

Cold viruses are easily spread by coughs and sneezes. This specialized photograph shows how far droplets are sprayed by a sneeze, even when a handkerchief is used.

In some people, a common cold may be complicated by a bacterial infection such as an infection of the chest (see Acute bronchitis) or of the sinuses (see Sinusitis). Bacterial ear infections, which may cause earache, are a common complication of colds (see Otitis media, and Acute otitis media in children).

What can I do?

Most people recognize their symptoms as those of a common cold and do not seek medical advice.

Despite a great deal of scientific research, there is no cure for the common cold, but over-the-counter drugs (see Cold and flu remedies) can help to relieve the symptoms. These drugs include painkillers to relieve a headache and reduce a fever, decongestants to clear a stuffy nose, and cough remedies to soothe a tickling throat. It is important to drink plenty of cool fluids, particularly if you have a fever (see Bringing down a fever). Many people take large quantities of vitamin C to prevent infection and treat the common cold, but any benefit from this popular remedy is unproved.

If your symptoms do not improve in a week or your child is no better in 2 days, you should consult a doctor. If you have a bacterial infection, your doctor may prescribe antibiotics, although they are ineffective against viruses.

The common cold usually clears up without treatment within 2 weeks, but a cough may last longer.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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