AIDS Home > HIV Transmission
The most common route of transmitting HIV is through unprotected sex with an infected person or sharing needles or syringes with an infected person. Transmission of the virus can also occur through contact with infected blood, but thanks to improved screening and heat treatments, infection through a blood transfusion is now rare. Casual contact or insect bites are not means of transmitting the virus.
HIV Transmission: An Overview
HIV (human immunodeficiency virus) can be spread in a number of ways. For example, it can be transmitted:
- Through unprotected sex
- Through infected blood
- Through contaminated needles
- From mother to child.
HIV is spread most commonly by having unprotected sex with an infected partner. The virus can enter the body through the lining of the vagina, vulva, penis, rectum, or mouth during sex. HIV can infect anyone who practices risky behaviors, such as:
- Sharing drug needles or syringes
- Having sexual contact, including oral sex, with an infected person without using a condom
- Having sexual contact with someone whose HIV status is unknown.
HIV transmission also occurs through contact with infected blood. Before donated blood was screened for evidence of HIV infection and before heat-treating techniques to destroy HIV in blood products were introduced, HIV was transmitted through transfusions of contaminated blood or blood components. Today, because of blood screening and heat treatment, the risk of getting HIV from such transfusions is extremely small.
HIV is frequently spread among injection drug users by the sharing of needles or syringes contaminated with small quantities of blood from someone infected with the virus.
It is rare, however, for a patient to transmit HIV to a healthcare worker or vice versa by accidental sticks with contaminated needles or other medical instruments.