Preliminary Considerations

The following factors are especially important to understand when discussing the spread of HIV:

1. Specific behaviors (not membership in a specific group) put a person at risk for HIV [Human Immunodeficiency Virus] infection. For example, people may be Gay or IV [Intra Venus] drug users but as long as they are not having sex without condoms or partaking in other high risk sexual practices, and are not sharing works, they are not at risk for HIV infection.
2. People may not consider themselves at risk of HIV transmission even though they are engaging in risky behavior. This assumption is usually made because they do not consider themselves as part of a risk group.

When thinking about routes of HIV transmission, two factors have to be taken into account:

1. The concentration of the virus in a transmission fluid, such as blood, semen, and vaginal secretions.
2. How such fluids enter the body.

Common Ways In Which HIV Is Transmitted

Sex: Any sexual activity in which blood, semen, or vaginal secretions enter another person's body through vaginal, oral, or anal sex should be considered a risk behavior.

Blood and semen have higher concentrations of the virus than vaginal secretions.

Pre-ejaculatory fluid (pre-cum) is also thought to be a transmissable fluid.

The anus and the vagina are more direct ports of entry into the bloodstream than the mouth or the head of the penis, so they are more succeptable to transmission.

Sharing Drug Works: It is the sharing of IV drug works (needles, syringes, cookers, cotton) - not the use of drugs - that puts a person at risk for HIV infection. A needle that was used for an injection can have residual infected blood in it. The next person to use the needle will directly inject this residual infected blood into her/his bloodstream either through a vein or skin popping.

IV drug users who use new needles or who properly clean their works with bleach, alcohol, or peroxide (including the needle, syringe, and cooker) and do not use anyone else's cotton or water are not at risk for HIV transmission from drug use.

Perinatal Transmission: Perinatal means "around the time of birth."

Perinatal transmission can occur from mother to fetus during pregnancy or from mother to child during delivery.

Although statistics vary, current estimates are that between 15% and 35% of the time HIV will be perinatally passed from pregnant women to their children.

The rate of perinatal transmission among babies studied since 1986 by the NYC-based maternal transmission study is 28%, which follows the rule that not every exposure leads to HIV infection. There is some evidence that transmission is more likely if the woman is HIV symptomatic, but asymptomatic women can also pass the virus to their children.

Infants born to HIV positive women will test HIV antibody positive at birth due to passive immunity - being born with some of their mother's antibodies. As infants develop their own immune systems (including antibodies) they replace the passive immunity antibodies with their own antibodies.

This process is usually completed by 8-10 months of age, but not later than 15 months. Most medical practitioners use 18 months as the cut-off point for a definitive antibody test result.

There have also been a small number of documented cases of transmission from mother to child through breast milk. In one such case, the mother was infected by a blood transfusion after her child was born and passed the virus to the child through breast-feeding. Risk from breast-feeding when a mother is infected prior to pregnancy is unclear.

Blood Transfusion/Blood Products: Blood products prior to April, 1985, were not screened for HIV, and recipients of such products before that time are at risk for HIV infection. Since then, all blood donated and used in the United States have been screened for HIV antibodies. Although HIV antibody tests are highly effective, there remains the very slight possibility that the blood was donated during the window period, or the period before HIV antibodies are detectable, and therefore would not test positive for HIV antibodies. Blood products such as those used by hemophiliacs can be heat treated, which kills any virus, and so may be safer than whole blood transfusions.

Occupational Exposure: Of the thousands of occupational exposure studies, there are forty cases of transmission documented by the Center for Disease Control [CDC]. Twenty-four of these had a documented HIV negative test at the time of their HIV exposure. Most were from sharp injuries (needle sticks, cuts from surgical instruments, injuries from suture needles). Universal precautions must be followed.