How is HIV transmitted?

There are only a few ways HIV can be transmitted. In New Zealand, almost all HIV transmission occurs through unprotected sexual contact. There are very low rates of transmission from direct contact with blood and from mother to baby transmission.

HIV must be present in large quantities in the following bodily fluids to be infectious:

  • semen
  • mucous found in the rectum
  • pre-cum (the fluid that the penis produces before ejaculation)
  • vaginal fluids, including menstrual blood (a woman’s period)
  • breast milk
  • blood

These fluids can transmit HIV through:

  • unprotected sexual intercourse 
  • from mother to baby during pregnancy or childbirth or
  • from breastfeeding, i.e., antenatal transmission or vertical transmission
  • from blood to blood contact, e.g., sharing injection needles while using drugs or in medical settings

HIV is not airborne and can’t be transmitted through:

  • Skin to skin contact, e.g., hugging
  • Kissing
  • Sharing cups, drink bottles or utensils
  • Other body fluids like saliva, sweat, or urine because they do not contain enough of the virus to infect another person


Because the HIV virus cannot pass through intact latex, the best way to protect yourself from HIV transmission during sexual intercourse is to wear a condom.