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How long can HIV live outside the body?

How long can HIV live outside the body?

  • HIV can survive outside the body for weeks

  • There has never been a case of HIV infection from casual contact with contaminated surfaces of potentially infected body fluids

I often get this question or variations on it for example:

How long can HIV survive in air?

How long can HIV survive on surfaces?

Let’s look at the evidence available to us.

  • HIV is killed by heat. Temperatures of above 60⁰C will kill HIV.
  • HIV is NOT killed by cold. In fact, colder temperatures increase the survival time of HIV.
    • At 27⁰C to 37⁰C, HIV can survive up to 7 days in syringes
    • At room temperature, HIV can survive in dried blood for 5 to 6 days
    • At 4⁰C, HIV can survive up to 7 days in dried blood
    • At -70⁰C, HIV can survive indefinitely
    • HIV can only survive in pH between 7 and 8
    • HIV has been found to survive for a few days in sewage
    • HIV has been found to survive in organs and corpses for up to 2 weeks

You would notice that all these studies are done on blood. There is really no good evidence to determine how long HIV from semen, vaginal secretions of other body fluids can survive outside the body. One fact is that it is very difficult to culture HIV from semen. This indicates the low viral content and we can assume that the same timelines for blood apply to semen if not less.

In these experiments, the survivability of the HIV virus is determined by its retention of the ability to infect cells in cell culture.

We must be careful not to equate survivability to infection. In other words:

HIV infected surface/fluid + broken skin ≠HIV infection

This is because there are many other factors that influence infection for example, the amount of virus has to be high enough in order to cause an infection. Also, when live HIV virus comes into contact with broken skin or mucosa, it still has to undergo a very complex series of steps before it actually causes a HIV infection. The mechanism of HIV infection is a lot more complex and will be discussed in detail in another article.

You would also note that these experiments were all done in a controlled environment of a lab. Many other factors such as wind, rain, humidity, type of surface etc are not taken into account.

Most people ask this question because they have been exposed to some potentially infected fluids and are afraid of being infected with HIV.

To date, there have not been any cases of HIV transmission via casual contact with surfaces or contaminated fluids.

HIV is transmitted via sexual intercourse, blood transfusion and sharing of infected needles. There have also been isolated cases of HIV transmission from dental treatments.

In summary, if you have touched some surface or fluid that you think might be contaminated with HIV, do not worry. You will not get infected.

If you have any questions, visit our free online forum on sexual health, HIV and STDs.

If you had a high risk exposure to HIV within the past 72 hours, you can take medicines to reduce your risk of actually contracting HIV. Find out more on HIV PEP Treatment.

If not read more about HIV symptoms.

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About Dr. Tan
Dr. Tan graduated from the National University of Singapore in 2001. His residency was in the two largest public hospitals in Singapore; Tan Tock Seng Hospital and Singapore General Hospital.

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689 Comments

  1. Quick question: Can you share a soap bar with an HIV infected person? What are the personal objects (excluding, obviously, razors) that you should NEVER share with someone who has HIV?

    Thanks.

    • There have been no validated cases reported of HIV transmission through sharing of any household objects. You can share soap bars, cutlery, toothbrushes, etc. Even razors are practically safe to share, although there is theoretical risk if there is significant contact with infected blood through an open wound.

  2. Hi there doctor, I was just curious as to why is HIV currently impossible to cure? I mean, why medicine can lower the viral load but not completely destroy the virus?

    Also, is it normal/common for someone on the first stage of AIDS to regress to having an undetectable viral load (after starting treatment of course)?

    • Regarding your first question, HIV infection and treatment is an extremely complex subject and not one which can be answered within the limits of a comments section. Suffice to say, there are clearly tens of thousands of researchers and millions of dollars being spent trying to answer that very question. As for your further query – yes it is normal for someone who starts on appropriate HIV treatment (even if they have progressed to AIDS) to regress to having an undetectable viral load – this is precisely the aim of treatment.

  3. Dr yesterday i accident on the rOad by motorcycle. My finger cut and have a lot of blood . And also my nail finger crack and fresh cut & bleeding . Its so hurt , someOne help me to stand up , and hold my hand , and his handshake my hand to say ” please take care ” . Om so worry now if his have hiv & also have fresh bleeding cut on his finger and when his touch my hand to help me stand up my fresh cut bleeding on hand & also my nail crack fresh cut bleeding contact with him finger fresh cut bleeding , so if his have hiv and have fresh bleedng cut in his finger can the virus hiv enter to my fresh cUt bleeding in my hand also fresh cut bleeding on my nail when we handshake together . 25years old i never do any exposure like anal , oral , kissing or etc . Imso shock if i got hiv from this situation , can i get hiv from this situation ?

    • No, I doubt you have any risk of contracting HIV in this manner. Why would that person have an open wound that is actively bleeding as well?

      • Coz i dont know , please doc if me & him got fresh bleeding cut on finger and the both fresh cut bleeding contact each other , and if his got hiv can the virus from his fresh cut bleeding on his finger enter to my fresh bleeding cut on my nail & finger from handshake

  4. Hello again Doctor, it’s me again. Sorry for bothering you once more but I’ve been waiting for a reply an I am also still a little worried because I’ve got a number of conditions this week that coincide with that incident with my familiar that has HIV (pretty bad timing so I don’t know what to think, are these illnesses unfortunate coincidences or…?). Since my story was quite long, I’m worrying that maybe you thought I was trolling or something (or perhaps you just haven’t had time, but you never know) but I’d like to let you know that isn’t the case and I would really appreciate a reply/some advice.

    Thanks again.

    • Your risk of HIV transmission from the events described is negligible, close to zero. But if you are concerned, do a check. There is no harm in that right? If you have symptoms and test now – if the symptoms are from HIV, the test will come back positive, whether or not you are in the window period. If you test negative, then you can know for certain that the current symptoms are NOT caused by HIV.

      • L. Leen

        Hello Doctor, just a question: Could bleeding gums be a symptom of HIV? An accident happened recently (nothing sexual or involving drug use, actually, just like another person here the accident involved food and an HIV+ person). I’m not known for having top dental/oral health but my gums rarely bleed, much less twice a day when brushing my teeth (first in the morning and then at night) so I found this odd… my throat too suddenly started hurting and I’ve got phlegm, stomachaches before going to the toilet and a little diarrhea. And I rarely get sleepy during the day because I work at home so I don’t really tire myself much, yet yesterday I suddenly became really sleepy for a moment and when I stood up (when I was still feeling sleepy), my knees felt really weak. Odd.

        Could these be symptoms? I read somewhere that symptoms start after two weeks or so and I started feeling like this after a week of the accident… but I don’t have confidence in having a strong immune system so… could that have affected the “symptoms” to appear earlier?

        Thanks for your response.

        • L. Leen

          Oops, “like another person here”, didn’t realize I was replying to the comment of that person. (BTW, I feel your pain L.G, I hope your test turns out negative!).

        • Gum bleeding would not be a common symptom, and 1 week post-exposure again seems a bit too soon. ARS symptoms are vague and non-specific, and at the end of the day if you are concerned the simplest thing to do is check.

      • Thank you very much for your reply Dr. Jonathan.

        Hm, may I ask why is it that, even if I’m not in the period of time in which it’s more sure to know whether or not there was infection (3 months, right?), if I have symptoms the test will come positive (in the case I was indeed infected)? Just curious.

        And this is probably a dumb question (I’m sure it is haha) but if I test even after the “symptoms” faded, if there was infection, the test should tell me, right? (Again, even if I’m not at the three month mark).

        Also, what do you think about the other person who DID ate from the POSSIBLY contaminated food (the three dishes)? Should that person do a test too even if they don’t have symptoms?


        And thank you L. Leen! I hope your test comes out as negative too. I’m hoping I’m just worrying too much because… well, I didn’t really eat any of the food that this person prepared (because I was too worried), I just got concerned because of these “symptoms”.

        • Essentially the symptoms of ARS are due to the antibodies created in your body reacting acutely against the viral antigens. The combo test is designed to pick up both the antigen and antibody that is circulating in the blood. So if you have symptoms from HIV, you will need detectable antigen/antibody in your blood. If the test is negative, then the symptoms are NOT due to HIV infection. The window period is 28 days if you are using the combo test, as it has been shown to have 100% sensitivity after this period. The 3 month window period applies to tests which check for HIV antibody only, not including antigen. Once the symptoms of ARS fade, the test will still pick up the antigen/antibody in the blood. There have been no verified cases of HIV transmission from ingesting contaminated food reported, so I really would not worry.

  5. K. Gee

    Hi doctor, I was wondering if there was any risk in touching surfaces that were recently touched by an HIV infected person (even if they had no visible blood on them) that was injured and then you touching your eyes or the inside of your mouth?

    Thanks in advance.

  6. Good afternoon Doctor. I live with a person who is HIV positive and has an “undetectable” viral load (though this person sometimes forgets to take his medicine). What happened was the following:

    On sunday 14, this person was cooking lunch for the whole family, and he accidentally cut himself while slicing potatoes with a mandoline. I rushed to see what happened and I took a quick glance at the bowl in which the sliced potatoes were being thrown into and I don’t remember seeing any drop of blood, so I dismissed there being any danger and I procedeed to take the mandoline away for washing while someone else put the potatoes for frying and this other person poured alcohol on the wound. I’m not too sure if he properly wahsed his hands, though.

    Later, this person instructed us to prepare some chards and he carelessly touched them with one of his hands (I think it was his non-injured hand but he obviously used said hand to wipe out the blood from his finger with a napkin, and as I said, I’m not sure if he properly washed his hands after the accident). By this point, I was freaking out but since we are poor, that was all we had to eat that day and trying to dispose of all those vegetables would have been really inconvenient and would have made the people I live with upset so with all the pain in my heart, I let it slide.

    We cooked the potatoes along with the chard in a soup.

    I didn’t actually eat the soup because I was too scared of there being small amounts of blood in it, but another person that was with us that day, did.

    And this other person kept touching things afterwards (no visible blood left behind but…) and while I was being quite careful to clean them with alcohol before I touched them too, I am kinda scared that I might have missed something.

    I’m not sure if I’m overreacting but I’ve been worried sick these days (for me and the other person who ate the soup) and on Friday 19 I started feeling unwell… I got phlegm in my throat and have had a little diarrhea (not too much diarrhea, only once or twice a day but still…). The other person who actually ate the food on the other hand, apparently doesn’t show any uneasiness, though.

    So my point is, what are the probabilities this stupid accident could have infected (either me or the other person)?

    I hope you can reply to my message and sorry for the long story.

    • By the way, when I washed the madoline, I don’t remember (yes, me and my bad memory)seeing any blood on the blade either.

      And I know this is going to sound really stupid but the person with the wound yet again made food in two more occasions during the week! (some fried bananas and yet another vegetable soup) and he obviously had to directly touch the fruit/vegetables when he was peeling them/cutting them (he was wearing a band-aid the third time, though).

      At this point I’m mad at this relative for being quite careless and I’m just sad that I didn’t notice him starting to make food these two other times so I could have told him “stop, I’ll make the food because you are injured”, but it already happened and now I can only ask what are the chances of accidentally getting infected and if we (the ones who don’t have HIV in the house) should take the test.

      • By the way, regarding this person touching surfaces with his hands (and me worrying about that) and then someone touching the same surfaces isn’t really how HIV is transmitted, I am actually worried because one can forget about this and then proceed to touch one’s nose/eyes/mouth (or even eat) after that.

        And sorry for bothering you so much, I just feel that it’s important to describe what happened so you can more or less give me an idea of what is the potential risk. Thank you very much for your time.

  7. Kenny

    Hello Dr. Tan

    Few days ago, I went to a government STD clinic to have a blood test, a nurse draw blood from my arm and then gave me a piece of cotton to press my needle wound to stop bleed.

    After about 10 mins, I moved out this cotton and touched my needle wound directly by hand to make sure if my wound stopped bleeding. I don’t know if this behaviour will cause any HIV infection? it is because my hand may touch HIV inflected blood and surface in the STD clinic without my intention.

    • No, you will not contract HIV in this manner.

      • Kenny

        Dear Dr Jonathan

        Thank you for your quick reply.
        One more thing I just want to reconfirm, HIV will not transmit from (blood>environmental surface>my hand>my wound), am I correct?

        thank you again~

  8. Hello,
    If someone ejaculates on your ass not your asshole just next to your ass from the outside, is that considered unsafe sex. Is it a risk .

    • This is not really considered unsafe sex per se. But even protected anal sex will have a certain degree of risk.

  9. Worried

    Hi Dr, recently i went for blood test in a clinic where they did blood test for hiv and stds also. Dr pricked my finger and took the blood sample, as I forgot to take the cotton to press my pricked finger and came outside and sit on a hospital cushion.Mistakenly I pressed my finger in cushion which was still bleeding and realizes it at later point of time. Is there any risk of hiv or hep b or c considering there might be dried blood on cushion already.

    • There have been no cases of HIV/hepatitis transmission in this manner. Do not worry.

      • Worried

        So doctor there is nothing to worry about even my finger was bleeding i pressed it on cushion for couple of minutes, pls let me know as i am really scared

  10. Hi Doctor.. Please help me to clarify on this. I engaged in mutual masturbation with a guy few days back. We didn’t ejaculate but we were just masturbating each other. I’m afraid if his precum touched my urethra when he masturbated me and urethra is a mucous membrane. Are there any chances for HIV transmission? I’m freaking out here.

    Also, a guy inserted a finger between my ass cheeks. He didn’t penetrate me or reached my anus, but just insert it between my cheeks. I quickly pulled up my pants and walked away to wash my ass cheeks after that. I’m scared if his finger had blood or precum or cum that time. But before that his finger was out at the air. Any risks ? Please kindly answer this Doctor​.

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