What are the differences between bacteria and viruses?
Although disease-causing bacteria and viruses cause many common infections, these organisms are not the same. Bacteria can live and are found both inside and outside the human body. Viruses, on the other hand, are much smaller in size than bacteria and cannot survive outside the body’s cells. Bacteria contain the genetic material they need to reproduce, while viruses need to invade healthy cells to reproduce.

What are antibiotics?
Antibiotics are powerful medicines used to treat some infections. However, antibiotics can be harmful when they are not used the right way. In fact, antibiotics themselves can also cause some germ-related problems, such as yeast infections of the vagina and mouth, and a severe form of diarrhea. Antibiotics should only be used when prescribed by a health care provider to treat bacterial infections.

How can I tell if an illness or infection is caused by a virus or bacteria?
Sometimes it’s difficult to tell. The following are some basic guidelines regarding some of the most common illnesses:

• Colds and flu — Viruses cause these illnesses. They cannot be cured with antibiotics. Both children and adults should consider being vaccinated with the influenza and pneumococcal vaccines. Ask your doctor or pediatrician.
• Cough or bronchitis — Viruses almost always cause these. However, if you have a problem with your lungs or an illness that lasts a long time, bacteria might actually be the cause. Your doctor might decide to try using an antibiotic.
• Sore throat — Most sore throats are caused by viruses and don’t need antibiotics. However, strep throat is caused by bacteria. A throat swab and a lab test are usually needed before your doctor will prescribe an antibiotic for strep throat.
• Ear infections — There are several types of ear infections. Antibiotics are used for some, but not all, ear infections.
• Sinus infections —A runny nose and yellow or green mucus do not necessarily mean you need an antibiotic. It is normal for mucus to get thick and change color during the course of a viral infection. For some long-lasting or severe cases, your doctor might decide to prescribe antibiotics.

So antibiotics won’t help cure all infections?
That’s correct. Antibiotics only work against infections caused by bacteria. They do not work against any infections caused by viruses. If you have a viral infection, antibiotics will not cure it, help you feel better, or prevent someone else from getting your virus.

What is antibiotic resistance and why should I be concerned?
Usually, antibiotics kill bacteria or stop them from growing. Antibiotic resistance occurs when bacteria adapt or change in a way that makes a specific antibiotic less able to kill them or stop them from growing. These "resistant" bacteria survive and multiply—causing more harm, such as a longer or more severe illness, more doctor visits, and the need for treatment with a more expensive and more powerful antibiotic. Over time, more and more bacteria are becoming more and more resistant to some of the most commonly used antibiotics. As this happens, fewer antibiotics are able to treat common, severe, and even rare illnesses caused by bacteria. To make sure the antibiotics that we already have remain effective, they must be used appropriately.

• Start by having an open-minded conversation with your health care provider about your illness and about antibiotic resistance.
• Ask if an antibiotic is likely to be effective in treating the illness.
• Don’t demand an antibiotic when your health care provider determines that one is not appropriate. Now you know that antibiotics don’t cure every illness and that you don’t need to take antibiotics for most colds, coughs, sore throats, or runny noses because these illnesses are mainly caused by viruses. Often, these illnesses simply need to run their course. Sometimes, this can take two weeks. Do, however, call your health care provider if your illness gets worse or lasts longer than two weeks.
• Ask what you can do to help relieve your symptoms. For example, measures that can help a person with a cold or flu feel better include: taking a warm bath, increasing fluid intake, using a cool mist vaporizer or saline nasal spray (available from the neighborhood drug store) to relieve congestion, or using a sore throat spray or ice chips to soothe the sore throat.

If your health care provider does determine that an antibiotic is necessary to treat your illness:

• Take the antibiotic exactly as instructed. Do not skip does. Complete the prescribed course of treatment, even if you are feeling better. Sometimes, if treatment is stopped too soon, some bacteria might survive and cause the illness to return.
• Do not save any antibiotics for the next time you get sick.
• Never take someone else’s antibiotic. Their antibiotic might not be appropriate for your illness, and taking the wrong drug can delay correct treatment and allow bacteria to multiply.

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