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Single exposure intravenous needle


I'm curious about the chances of contracting HIV through a singular intravenous use of a (possibly) contaminated needle. Person at risk isn't intravenous user, has never had sex, and this was first and only time doing intravenous injection. Person assisting with injection possibly is positive and may have intended to infect. Person at risk was told was new, clean needle, but may have been lied to.



Thank you for your inquiry. From what we gather from the question, you were asking about acquiring HIV through injecting with a possibly contaminated used needle. From the information given, this scenario is determined to be High Risk (Evidence of transmission through these activities and is the majority of cases of transmission).

The scenario mentioned above does meet the three components of the transmission equation. The transmission equation requires an exchange of bodily fluid from a HIV positive individual to a HIV negative individual through high risk activity with direct access into the bloodstream (1). This scenario satisfies the equation as an exchange of bodily fluid could have occurred and using shared needles is a high risk activity which has direct access to the bloodstream. If the needle had blood from an HIV positive individual it could be transmitted to a HIV negative individual (2). When an individual is high from using drugs these individuals are also more likely to engage in risky sex (2).

HIV does not survive long outside the body (3). However it is important to consider that HIV in blood can survive over 40 days in a completely sealed environment (i.e syringe) (3). If one is penetrated with a syringe that contains the HIV virus there is a chance that transmission will occur (3). This is considered a high risk practice for HIV transmission (3).

Recommendation: Refer to Physician for HIV test. In order to lower your chance of getting HIV through intravenous injection it is recommended to stop injecting drugs (4). If you choose to continue to engage in intravenous injection to lower your chances of transmission use new, sterile needles and paraphernalia every use, if you share needles to bleach used needles, and if engaging in sexual activity use protected measures (4). Clean needles and paraphernalia can be obtained from various needle exchange and supervised consumption sites (local needle exchange sites in the metro Vancouver: http://www.vch.ca/public-health/harm-reduction/needle-exchange). If you are continuously engaging in high risk activity in this scenario there are biomedical approaches such as PrEP **and **PEP that help lower your risk of acquiring HIV. Refer to your physicians for further information.


AIDS Vancouver Helpline/Online, Danielle