What is a cold?

A cold is a contagious upper respiratory infection that is caused by a virus. More than 200 different viruses can cause colds.

According to the National Institutes of Health, Americans come down with more than 1 billion colds a year. Young children get more colds than adults because of their close contact with other children and because they are being exposed to viruses for the first time. Germs also spread more in colder months because people stay indoors and are in closer quarters with each other.

How are colds spread?

Colds are spread from one person to another through direct contact or by inhaling droplets of fluid that contain a cold virus. Cold viruses must reach the mucous membrane, the moist lining of the nostrils, eyes, or mouth, in order for a person to become infected.

Someone who has a cold probably has particles of a cold virus on them. Many surfaces may also have particles of a cold virus on them. If you touch an infected person or surface and then touch your eyes, nose, or mouth, you are more likely to catch a cold.

What are the symptoms of a cold?

  • Runny nose
  • Sneezing
  • Cough
  • Sore throat
  • Headache
  • Nasal congestion
  • Fever may be present, especially in children

These symptoms usually occur two to three days after infection and will usually end in seven to 10 days.

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