Hello everyone,

I gathered from the posts here that hiv is not transmissible once out in the air and also that you cannot get it from/through food, however I have a question on the time frame that this is valid for:
Noticed after dinner with a friend a large wet spot next to my plate - table was dark wood so couldn't say which colour the spot was, but I'm worried now that this could have been blood from one of the waiters who had served us. If I had now unknowingly touched this spot and my lips straight after (as my fingers go over my lips sometimes), could I have been at risk? I know apparently there have been no reported cases of transmission through objects or food, however would it be technically possible? Also, I cannot guarantee how much time has passed between presence of (bloody?) spot and mouth contact, could have literally only been a couple of seconds....does this make a difference? Also, would it make a difference if I had sore spots inside my mouth from brushing my teeth?!

Sorry for all the questions but thanks a lot for answering!!
Hi there and thank you for contacting the Helpline,

No need to say sorry about your questions! That's what we're here for.

So, let's first talk about that large wet spot. Though it could possibly be from a bodily fluid, such as blood, this doesn't seem too likely. Imagine if you were working as a waiter/waitress and you got a cut and were bleeding onto a table... Would you clean up the blood or just leave it? And if you could not get the blood out, would you really continue serving people on that table? This would be a huge health hazard and likely the restaurant would not risk anything by using that table.

But, say it was blood and you did touch it before touching your lips... You would still be at No Risk of acquiring HIV. The time it takes for HIV to become non-transmittable due to contact with air is almost instant, within seconds. But again, even if you touched the wet spot and then your lips within seconds, you would still be at No Risk. This is because it isn't possible to acquire HIV through skin contact (your lips), nor is it possible for the virus to enter your bloodstream through your mouth if there is no access point. The mucous membrane of the mouth is different from other mucous membranes (urethra, vagina, anus) - it doesn't allow for transmission so easily. You would need some sort of access point, such as from having fresh major dental work, for the virus to enter.And even with this access point, it would require large volumes of bodily fluid entering your mouth for transmission to occur. In addition, your saliva contains enzymes that work to damage the virus so that it cannot transmit.

About the sore spots in your mouth from brushing your teeth, these would not make a difference in your risk because of all of the above reasons. They would not provide an access point for the virus to enter your bloodstream - this would require a much larger type of opening (such as from major dental work as I mentioned earlier).

If you're interested, here is a great web page to look at with all of the HIV transmission basics: Our HIV transmission equation might help you too. Take a look:


---------- -------- ----------------------------
• 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

I hope that this information will help you to be less stressed about HIV transmission in future No-Risk situations!

Again, thanks for contacting us and please do so again if you have remaining questions. When you ask questions, other Online Helpline users get to see the answers too! Many of them likely have similar concerns.

AIDS Vancouver Helpline/Online

Monday-Friday 9am-5pm (PST)

1 844 INFO-HIV (Toll free Canada & U.S.)

Private & Confidential**


Charitable Registration #
10668 9896 RR0001

© 2019
Privacy Policy


1101 Seymour Street
Suite 235, 2nd Floor
Vancouver, BC V6B 0R1


Main Phone: 604-893-2201
Fax: 604-893-2205