Treatment

Knowing what type of germ is causing your illness makes it easier for your doctor to choose appropriate treatment.

Antibiotics

Antibiotics are grouped into "families" of similar types. Bacteria also are put together in groups of similar types, such as streptococcus or E. coli.

Certain types of bacteria are especially susceptible to particular classes of antibiotics. Treatment can be targeted more precisely if your doctor knows what type of bacteria you're infected with.

Antibiotics are usually reserved for bacterial infections, because these types of drugs have no effect on illnesses caused by viruses. But sometimes it's difficult to tell which type of germ is at work. For example, pneumonia can be caused by a bacterium, a virus, a fungus or a parasite.

The overuse of antibiotics has resulted in several types of bacteria developing resistance to one or more varieties of antibiotics. This makes these bacteria much more difficult to treat.

Antivirals

Drugs have been developed to treat some, but not all, viruses. Examples include the viruses that cause:

• HIV/AIDS
• Herpes
• Hepatitis B
• Hepatitis C
• Influenza

Antifungals

Topical antifungal medications can be used to treat skin or nail infections caused by fungi. Some fungal infections, such as those affecting the lungs or the mucous membranes, can be treated with an oral antifungal. More-severe internal organ fungal infections, especially in people with weakened immune systems, may require intravenous antifungal medications.

Anti-parasitics

Some diseases, including malaria, are caused by tiny parasites. While there are drugs to treat these diseases, some varieties of parasites have developed resistance to the drugs.