Question: Why is injecting drugs a risk for HIV?
Answer: At the start of every intravenous injection, blood is introduced into needles and syringes. HIV can be found in the blood of a person infected with the virus. The reuse or sharing of a blood-contaminated needle or syringe by another drug injector (sometimes called "direct syringe sharing") carries a high risk of HIV transmission because infected blood can be injected directly into the bloodstream.
In addition, sharing drug equipment (or "works") can be a risk for spreading HIV. Infected blood can be introduced into drug solutions by
- using blood-contaminated syringes to prepare drugs
- reusing water
- reusing bottle caps, spoons, or other containers ("spoons" and "cookers") used to dissolve drugs in water and to heat drug solutions
- reusing small pieces of cotton or cigarette filters ("cottons") used to filter out particles that could block the needle.


