Transmission of HIV

HIV infection is transmitted primarily through:

  • Unprotected sexual intercourse;  
  • Transmission through contaminated blood;  
  • When a mother infects her baby during pregnancy, during childbirth or as a result of breastfeeding.


Transmission through sexual acts
In this section, read more about:

  • Sexual intercourse with an HIV-infected person  
  • How does HIV get into the body during sexual intercourse  
  • Why are women more easily infected by HIV than men?  
  • Can lesbians get Aids?  
  • Can one be infected with HIV through having oral sex?  
  • How many sexual contacts with an HIV-positive person are necessary before one becomes infected oneself?  
  • Is it true that circumcision can protect males against HIV infection?  
  • If I am HIV+, why should I still use a condom to protect myself?  
  • Transmitting HIV through contaminated blood  
  • How safe is our blood supply in South Africa?  
  • The danger of sharing contaminated needles  
  • The risk when one person has been accidentally exposed to the blood of an infected person?  
  • How long can the virus survive outside the body?

Transmitting HIV through contaminated blood
Did you know that HIV can be transmitted by unsterile or dirty instruments used for circumcision? There are many other ways that HIV is transmitted though contaminated blood.
The HI virus can be transmitted from one person to another when:

  • A person receives HIV-contaminated blood in a blood transfusion,  
  • When a person is exposed to needles that are contaminated with HIV-infected blood in the process of injecting drugs,  
  • When a person (eg a health care worker) is injured with blood-contaminated needles, syringes, razor blades or other sharp instruments  
  • Unsterile or dirty razors, knives, needles or other instruments are used during cultural practices such as circumcision, scarrification, or blood letting.

Mother-to-child transmission of HIV (MTCT)

  • Why are only some babies of HIV+ women infected and others not?  
  • Should an HIV+ woman breastfeed her baby?

Myths about the transmission of HIV

  • How HIV is not transmitted  
  • Myths can be very dangerous

Graphic: How the virus enters the body

Provided by ArmMed Media
Revision date: July 3, 2011
Last revised: by Jorge P. Ribeiro, MD