A: The common cold, the most common illness of all, has been the focus of much folklore and research. You've probably heard or even said the following: 'Close the window or the baby will catch a chill.' 'Put on your sweater or you'll catch a cold.' 'Don't go out in the rain or you'll catch pneumonia.' Although some age-old advice might be helpful, parents need to understand what the current research says about colds to help keep our children healthy.

What causes a cold?
Contrary to its name, a cold is not caused by exposure to cold air—it's caused by a virus infection. Colds are also known as Upper Respiratory Infections or URIs, and 200 different kinds of viruses have been found to cause them. Studies have shown that people who were exposed to a respiratory virus got sick with a cold, while people simply exposed to cold air did not get sick. Interestingly, those exposed to the virus plus cold air were no more likely to get sick than those exposed to the virus alone.

Why, then, are colds more common in the fall and winter? The cold weather doesn't give children colds, but it makes them spend more time indoors where they spread the viruses to each other. In fact, keeping children indoors with the heat turned up and the windows shut actually makes them more likely to catch colds.

How are colds spread?
The respiratory viruses affect the respiratory or breathing system—primarily the head and chest—causing stuffy nose, runny nose, sore throat, cough, and sometimes a low-grade fever. The respiratory viruses are found in an ill child's mucus and saliva from several days before the symptoms develop until the end of the illness, usually within a week. The viruses spread easily from one child to another through the air and by touching—for example, in situations such as:

• When a child coughs, the virus in his saliva is sprayed into the air—then it's breathed in by another child.
• When a baby puts a toy in her mouth, the virus in her saliva gets on the toy—then she puts the toy down and another baby picks it up and puts it in his mouth.
• When a child wipes her runny nose with her hand, the virus in her mucus gets on her hands—then she holds hands with another child and the other child touches her own eyes, nose and mouth.

How do you prevent the spread of colds?
It's probably inevitable that your child will get some colds. Infants and toddlers average 10-12 colds per year, preschoolers average 5-6 per year, and older children and adults typically get fewer. Although it's miserable to have a cold, the good news is that exposure to the viruses helps children develop immunity to help prevent future colds. And staying healthy with good nutrition, enough sleep, and exercise helps to keep the immune system strong.

Here are some good tips to help prevent the spread of colds:

• Wash hands frequently: Handwashing is probably the most important way to reduce the spread colds and many other illnesses. Be sure to wash your hands after wiping noses, going to the bathroom, and diapering your baby, as well as before preparing meals and feeding your baby. Make sure your child also washes her hands after diapering or going to the bathroom and before eating.
• Don't share food or drinks: Although we encourage our children to share, we don't want them to share germs. Make sure each child has his own food and drink. At family meals, teach your child to touch only what he'll eat.
• Avoid kissing your children on the mouth: Most common illnesses such as colds, flu, and herpes cold sores can spread through germs in the mouth. It's safest to kiss on the forehead or cheek.
• Cough or sneeze into your elbow: Although you probably learned to 'cover your mouth when you cough,' this sprays saliva and germs onto your hands. If you don't wash your hands right away, you spread the germs when you touch people and objects afterwards. It's better to keep your hands clean by coughing and sneezing into your elbow. Children as young as 2 or 3 years old can learn to do this, too.
• Clean toys regularly: Infants and toddlers tend to put toys in their mouths. The easiest way to clean plastic toys that don't have batteries is to run them through the dishwasher. If you don't have a dishwasher, wash the toys with soap and water, then dip them in a bleach solution (1 tablespoon bleach to 1 quart of water) and let them air dry in a rack. For toys with batteries, just clean the outside with soap and water, then wipe with the bleach solution. You can clean fabric toys in the laundry.
• Make sure your baby gets fresh air: Fresh air is healthy for children and adults, even in cold weather. It's healthiest to open windows for a short time every day, and take your baby outdoors at least once a day.