Infections are caused by germs, which are in the air you breathe and on everything you touch. Two types of germs are bacteria and viruses:

• Infections are most commonly caused by viruses. Colds and influenza (flu) are examples of illnesses due to viruses.
• Infections caused by bacteria are less common. Strep throat, bladder and skin infections are examples of illnesses caused by bacteria.

When germs enter your body, they can cause an infection and you may get a fever. Fever is a sign that your body is fighting to kill the germs. Some germs can live for days outside the body of the sick person they came from.

What are antibiotics and how do they work?

Antibiotics are drugs that doctors prescribe to kill infections caused by bacteria. They do not kill viruses. An antibiotic will not help your child get better if they have a virus. However, there are drugs called antivirals that are used to treat serious infections from viruses such as influenza or chickenpox.

Antibiotics kill bacteria or stop them from growing and reproducing. There are many different kinds of antibiotics. Different bacteria are killed by different antibiotics.

Recently, though, some have stopped working to kill certain bacteria. These bacteria have become “resistant” to antibiotics. When an infection can’t be treated with the usual antibiotics, sometimes newer (and often more expensive) drugs must be used.

Why have bacteria become resistant to antibiotics?

If an antibiotic is used for the wrong reason, in the wrong dose, or for the wrong amount of time, bacteria can become resistant to the medicine. The main reason bacteria have become resistant is because antibiotics have been used too much.

How can you help prevent antibiotic resistance?

• Make sure your child receives antibiotics only to treat an infection caused by bacteria. Cold are caused by viruses, and should not be treated with antibiotics. Ask your doctor what the infection is and if an antibiotic is necessary.
• When your child is sick, it’s best to see her own doctor. That way, the record of all her medication use will be in one place. Avoid going to different walk-in clinics if you can.
• If your child is prescribed antibiotics, be sure to give them according to the instructions.
• Never use antibiotics prescribed for someone else.
• Never use antibiotics left over from a previous illness. If you have unused antibiotics in your house, you should bring them to the pharmacy for safe disposal.

Reviewed by:
CPS Infectious Diseases and Immunization Committee

Last updated: March 2011