« Go Back

Why small cut, scatch NO RISK?

Question: 

Hi Doctors.
I saw many questions about handjob, small cut/scratch on the penis or hand contacted blood/fluid contains HIV+ from your website. All your answers were NO RISK with hiv because HIV could not transmit if it was outside the body and exposed to air and because the cuts/scratch is small. While you said HIV can transmit by share needle drug. I do not understand why in case share needle the blood is outside and exposed to air and the cut is very very small, too. I saw CDC Center. They said the cut/sore are possible? What difference between you and CDC Center. Please explain to me.
Thanks.

Answer: 

Hi there, and thanks a lot for contacting the AIDS Vancouver Helpline for your HIV/AIDS related health information. It seems you're concerned about the possibility of HIV transmitting through a cut. We're happy to answer your question for you.

Before we answer, we'll include the transmission equation again as it has some important points required to understand the risks involved with cuts:

HIV TRANSMISSION EQUATION

BODY FLUID
+
ACTIVITY
+
DIRECT ACCESS TO BLOODSTREAM
• blood (including menstrual) • unprotected anal or vaginal intercourse • vagina
• semen • sharing needles • anus
• pre-cum • mother to child (in specific cases) • urethra in the penis
• rectal secretions • open cuts and sores (in theory)
• vaginal fluids • other mucosal membranes
• breast milk • points of needle injection

= RISK OF HIV TRANSMISSION

You'll see in the chart that required for transfer are all of (you need all three for a transfer to occur) an activity known to be involved in transfer (such as sharing needles), a fluid known to be involved in transfer, and direct access to the bloodstream. There are a few key differences between a fluid coming into contact with a cut and injecting yourself with a needle potentially containing someone else's blood. For one, the barrel of the needle provides an environment for blood to not come into contact with air, so the virus is able to remain transmissible long enough for a transfer to occur. Second, the needle gains direct access to the bloodstream when it is injected into a blood vessel (direct access to the bloodstream is supplied). When you have a fluid come into contact with a cut, blood is exposed to the air for a longer period of time and it is not directly injected into a blood vessel, so transfers are lot more rare. You may have seen that there is a very very small risk of a transfer occurring with a cut. It is so low that we can say that it is essentially not possible, so we deem it "no risk." We can assure you that the risks are substantially greater when sharing needles.

We hope this has answered your question. Thanks for contacting the AIDS Vancouver Helpline with your question.

Trevor

AIDS Vancouver Helpline/Online
helpline.aidsvancouver.org