Glossary

To be protected or safe from something. There are vaccines (special medicines) that can make you immune to certain diseases, like Hepatitis B. This means that if you get the vaccine, you can't get the disease.

A group of cells that defend or protect the body from viruses, bacteria, and other germs by killing them. Lymph nodes and white blood cells are two parts of the immune system.

The time period it takes for a person to know he or she has a disease. The incubation period starts on the first day a person is exposed to the disease. Depending on the disease, this can be as short as a few days or more than 10 years. Even though an infected person may feel perfectly healthy and show no symptoms during a disease's incubation period, they still can still give the disease to another person.

Another way to say that someone has "caught" a germ is to say they are infected. If you are infected with a disease-causing germ there is a certain amount of time (called an incubation period) between the time you get infected and the time that you show symptoms (signs) of the disease.

People who use needles to put drugs into their bodies. Drugs like heroin, cocaine or speed can be injected into a person's veins. Steroids are usually injected into someone's muscles. People who share needles can get HIV or other blood borne infections like Hepatitis B. The blood that gets into the needle/syringe/case (where the drugs are put) from one person's body can then get into another person's body when they use the same needle. The risk of catching an STD through needles can be stopped by either not sharing needles or sterilizing them between uses.

See "sexual intercourse."

When something is put directly into someone's veins, such as legal medicines or illegal drugs.