Fourth-generation HIV testing is very sensitive, which means that there is a small chance a "reactive" or positive result is false. A negative result is always accurate, unless you have been exposed to HIV within the last two weeks. If you have been exposed to HIV in the last two weeks, it's too soon to test. You should wait two weeks from the last possible exposure* before getting an HIV test. If you’re concerned about something that happened more than two weeks ago, but also had more recent exposure, you can consider getting tested now and returning in a month or two for a repeat test.
* — possible exposures include:
- Unprotected vaginal, anal, or oral sex
- Sharing needles or "works"
- When a condom breaks or slips off during sex
- Sexual assault
- Sharing sex toys
- Contact with another person's blood
Have more questions? Send your questions to Boston HAPPENS and we will get back to you within three days. For testing hours and directions, see our counseling and testing page.