HIV is found in the body fluids of a person living with HIV. There may be enough HIV to be infectious in semen, genital fluids*, blood and breast milk.
*Definition of genital fluids: Vaginal and cervical secretions, semen (cum), pre-ejaculate (pre-cum) and rectal secretions
To pass on the virus, infected body fluids need to get into someone else’s bloodstream.
HIV can be passed on by receiving blood transfusions or other blood-related products from someone living with HIV, or donations of semen (artificial insemination), skin grafts and organ transplants. However, in the UK, donated blood has been screened for HIV since 1985. Similarly, screening is in place for organ and sperm donation.
HIV isn’t actually as infectious as many other sexually transmitted infections (STIs). It isn’t automatically passed on every time a positive and a negative person have condomless sex, for example.
Other factors that can affect the risk of HIV being passed on:
If you’re on HIV treatment, there is an extremely low risk of you passing HIV to your partner through unprotected vaginal or anal sex as long as:
Condoms are still the best way to prevent the spread of STIs.
Before you make any decision about not using condoms, get advice from your HIV doctor or nurse.
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This article was last reviewed on
by Anna Peters
Date due for the next review: 23/11/2018
Content Author: Kerri Virani
Current Owner: Kerri Virani
STIs make no difference to transmission risk in those with suppressed viral load:
Davies O et al. Impact of rectal gonorrhoea and chlamydia on HIV viral load and inflammatory markers in the rectum; potential significance for onward transmission. BHIVA conference, Thursday 23 April 2015, abstract O19
Impact of rectal Gonorrhoea and Chlamydia on HIV viral load in the rectum; potential significance for onward transmission, Olubanke Davies, Sinead Costelloe, Juan Tiraboschi, John White, Siobhan O’Shea, Julie Fox, Presentation from BHIVA conference 21-24 April 2015
Men taking HIV treatment have undetectable viral loads in the rectum; sexually transmitted infections make no difference, NAM, Aidsmap, Roger Pebody, 24/4/15
Condoms, NHS Choices, 13/1/15
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