HIV transmission

Updated on:
November 16, 2021

What ways can HIV be transmitted?

Anyone can get HIV, regardless of age, sex, gender, sexuality, and ethnicity. There are five bodily fluids which have the potential of transmitting the virus:

  1. Blood
  2. Semen (includes pre-cum)
  3. Vaginal fluids
  4. Anal fluids
  5. Breastmilk

It is only when one of these fluids enters the blood of somebody else that there is a risk of HIV transmission. Transmission can occur through: broken skin, penis opening, vagina, rectum, foreskin. The behaviours that are responsible for most HIV transmission are sex and sharing needles.

Without proper treatment, HIV can also be passed from a pregnant person to their baby during pregnancy, birth, and breastfeeding. However, with effective treatment it is likely that HIV positive parents will give birth to HIV negative babies.

How is HIV NOT transmitted?

Any fluids that were not mentioned above do not carry enough HIV to transmit the infection. HIV cannot be transmitted by: shaking hands, sharing food, hugging and kissing, coughs and sneezes, spit, insects, etc.

All Canadian blood products in Canada have been checked for HIV since 1985 and there has not been a single case of transmission through blood products since that time.

How to prevent the transmission of HIV?

Condoms and lube

Using a condom correctly and consistently helps prevent HIV and STIs. Using lube can help prevent tears which can facilitate the transmission of HIV and STIs. When using condoms, make sure to use only water or silicone based lubricants. An oil based lubricant can cause the condom to break.

HIV treatment

If somebody is living with HIV and on treatment, their viral load is suppressed, making it impossible for them to transmit HIV during sex. HIV treatment not only ensures somebody stays healthy, but it also prevents transmission.

Pre-Exposure Prophylaxis (PrEP)

PrEP is a form of HIV prevention for those at higher risk of HIV, taken before a possible exposure to the virus. Essentially, PrEP is a pill that is taken everyday to prevent HIV for those who could benefit from additional prevention; it is 99% effective when taken everyday.

This pill currently comes in three forms (all equal levels of protection when taken daily): Truvada, generic Truvada, & Descovy.

Post-Exposure Prophylaxis (PEP)

PEP, on the other hand, is a way to prevent HIV after a potential exposure to the virus. PEP is usually an emergency resource for those who have been in a situation where HIV may have been transmitted (condom breakage, sexual assault, needle-injuries). PEP is started within 72 hours of the exposure, but is most efficient when taken even sooner (i.e. as soon as possible). PEP must be taken daily for 28 days to be fully effective.

Sexual behaviour

There are some types of sex that present a higher HIV risk than others. Oral sex poses little-to-no risk and masturbation poses no HIV risk, whereas receptive anal sex carries the highest risk. Avoiding sharing toys and cleaning your toys between use can also decrease the risk of HIV transmission .

Using new needles and safely disposing of needles

If you inject drugs, you may be at higher risk for HIV. In order to decrease your risk of transmission, you can use new needles every time you inject drugs and avoid sharing drug equipment (like cookers, filters, water, pipes, straws) by using your own equipment every time.

For a more in-depth look into HIV prevention methods, see our article on HIV Prevention.

Reviewed by:
Dr. Caley Shukalek

Caley is passionate about evidence-based, patient-centred care, including telemedicine that can provide high quality care from wherever a patient may choose.

He helped create Alberta's PrEP guidelines and works as a specialist in General Internal Medicine with additional training in sexual health, including HIV and sexually transmitted infections.

He holds an Masters of Public Health from Johns Hopkins University, an MD from the University of Calgary and an MSc from the University of Alberta.