The symptoms

WHAT ACTIVITIES ARE MOST RISKY?

The highest risk of becoming infected with HIV is from sharing needles to inject drugs with someone who is infected with HIV. When you share needles, there is a very high probability that someone else's blood will be injected into your bloodstream. Hepatitis virus can also be transmitted by sharing needles.

The next greatest risk for HIV infection is from unprotected sexual intercourse (without a condom). Receptive anal intercourse carries the highest risk. The lining of the rectum is very thin. It is damaged very easily during sexual activity. This makes it easier for HIV to enter the body. The "top" or active partner in anal intercourse seems to run a much lower risk. However, the risk still seems higher than for the active partner in insertive vaginal intercourse.

Receptive vaginal intercourse has the next highest risk. The lining of the vagina is stronger than in the rectum, but is vulnerable to infection. Also, it can be damaged by sexual activity. All it takes is a tiny scrape that can be too small to see. The risk of infection is increased if there is any inflammation or infection in the vagina.

The risk is higher for the receptive partner. However, there is some risk for the active partner in anal or vaginal sex. It's possible for HIV to enter the penis through any open sores, through the moist lining of the opening of the penis, or through the cells in the mucous membrane in the foreskin or the head of the penis.