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HIV – Understanding the Window Period

Asian Geographic article on HIV

Asian Geographic article on HIVThe HIV window periodoften is the cause of a lot of confusion.

There is a lot of information on the web throwing up numbers like 3 months, 6 months even 1 year. So what exactly if the HIV window period?

To better understand this, let us take a step back in time to when HIV was first discovered. At the same time, learn a little about how our immune system works.

The HIV virus was discovered in 1983. Prior to that, it was not known what was causing the disease known as AIDS that was ravaging certain communities in the world.

After scientists discovered the existence of the HIV virus, they had to find a way to determine if a person has this virus in his body or not.

The ELISA Test and Our Immune System

In 1985, they developed a test called ELISAwhich is based on a very basic principle of how our immune systems work.

When our body is attacked by a virus, it will produce anti-bodies to fight the virus. Anti-bodies are unique. The anti-bodies used to fight HIV would be completely different to the ones used to fight dengue, for example, or any other virus.

So finding HIV anti-bodies in the body is indirect evidence that there is HIV virus in the body too. The ELISA test does exactly that. It tests for the presence of HIV anti-bodies. HIV rash

Imagine each virus infection is a fire that starts in the body. Each of these fires produces a uniquely colored smoke. When we see a particular colored smoke, we assume that there is that particular type of fire burning away. The ELISA tests for HIV colored smoke but does not detect the fire itself.

But there was one big problem. It sometimes takes the body a long time before the body produces enough anti-bodies to be detected by the ELISA test. In other words, the fire has to burn for a long time before it produces enough smoke that can be detected by ELISA.

This period when a person is infected with HIV and the ELISA test is unable to pick it up (the period when the fire is burning but there is no smoke) is called the window period.

This was correctly recognized to be a very important finding and rightly so because a person infected with HIV within the window period can get tested and be told he does NOThave HIV. He will then not take steps to protect himself and the people around him thus increasing the risk of spreading the disease.

Different Types of HIV Tests

Click on the picture for the latest information on the HIV testing Window Period

Click on the picture for the latest information on the HIV testing Window Period

Click here for HIV Testing FAQ

Scientist has ever since been working on improving and coming up with new and better testing techniques and technology. There are now multiple different tests for HIV including ELISA, ECLIA, CMIARapid HIV Tests, Western Blot, RNA PCR, DNA PCRand P24 Combo Tests.There are also multiple different manufacturers of each test. All of these tests have their own rates of accuracy, window periods and applications in the management of HIV. To make things even more confusing, there are also tests for indirect evidence of HIV infection like CD4 cell count and CD4 CD8 cell ratio.

So when you read somewhere or someone tells you that the window period for HIV is X number of months, your next logical question should be ‘by using which test?’ – HIV Test Singapore

To know which test done when has what accuracy requires a lot of professional knowledge. This information is also constantly changing as more and more research information is published. There are also other considerations such as waiting time, anonymity, costs etc

It is still best to speak to Our Doctors who are certified and trained in HIV counseling and testing to find out which test is most appropriate for you. Anonymous HIV Testing

Click here for Updates on the HIV testing Window Period

One thing remains constant. If you are at any risk of HIV at all, no matter how minute, you MUSTget tested. But as for which test to do and when to test, it is still best to speak to a medical professional trained in HIV matters.

Click here to learn about the Different Generations of ELISA

The HIV Window Period and Test Accuracy

HIV PEP Post Exposure Prophylaxis


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Your are welcome to visit Our Doctors at Our Clinics anytime during our opening hours .


Need more advice?

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  1. Dear dr
    I have protected sex with a sex worked about 15 min halfway the girl give me unprotected hand job and carry on with condom sex
    Now what can I do dr
    Can i have protected sex with my wife?

  2. Hi Drs!
    I had a 4th generation test done on the 27th day after possible exposure in the infectious deseases centre of the hospital. They told me that it was accurate and definitive at 1 month after possible exposure (so 4 weeks, 28days as you state also). My question is: can I class my test definitive or does one day makes any difference?
    Thanks in advance for your amazing service here

  3. Hello from the UK. I had unprotected sex with a lady and had a 4th generation test at 32 days which came back negative.Should i have another one at 3 months or is this conclusive?. Sorry to ask but there is so much conflicting information on the internet. Many thanks for your time and expertise.

    • We are very happy with calling a 4th gen test conclusive at 28 days or more, which is in line with WHO guidelines. However, it is always best to clarify with your own doctor regarding local guidelines.

  4. Dear Sir,
    I had unprotected vaginal sex with a woman. Later on I found out she had HIV. I had a combo test (4th gen) done exactly 28 days after exposure. It was negative. I´m thinking about having another one done after 45 days. Which are the chances my previous test is a false negative?

    Thank you

    • I believe your test is conclusive and there is no reason for a false negative. But if you are concerned and are getting tested anyway, no harm in that.

      • I had a new 4th generation test done today (45 weeks after exposure and after my first negative at day 28) and still waiting for my results. The thing is I´m terrified with the idea of a false positive with this new test, now I was begining to get confident I had left all this behind. Besides I felt a little sick in the stomach these days and I´m afraid having some kind of stomach virus might give place to a false positive. Is that possible?

        I have another question. In the country where I live (Spain) the advised window period for a 4th G combo test is 45 days. Why is that so? Are low-quality tests used here or are the autherities being over-conservative?

        Thanks in advance.

        • Well, I got the result from my last 4th generation test (done 45 days after exposure). It´s a negative again.

          Is this deffinitive? Does it mean I can forget about it and go on with my life?

          Thanks in advance

  5. I had 9 weeks hiv 4th generation combo test negative and hep c.ab to ,pcr,rna qn test non reactive. Both non reactive. Is I m ok. I happnes year ago.

  6. Hello , i take a 5th generation hiv test after 45 day , IT vas negative , IT is safe ?

  7. Hi Doctor

    Had anal sex (i am bottom) and condom broke and just realize half way.
    Second day got fever and muscle ache.
    Can do test directly? Got chance positive?

    • There is risk of HIV transmission from this exposure. The window period for testing is 28 days for conclusive results. The earliest we can detect is 14 days with a 4th gen test, or 10 days with HIV RNA PCR. If your exposure is within 72 hours please visit us to discuss post-exposure prophylaxis (PEP).

  8. Hello Dr Tan,
    Two weeks before I went for massage with a thai lady she proposes me to do sex but I refuse it then we both removed our dress and she do massage for me after that I hug her and lick her nipples during the licking of her nipples my penis got rubbed on her thighs now am afraiding if there is some menstrual blood on her thighs and it got contact with my penile head means is there any chance of hiv please doctor please advise me I need to do any hiv test

  9. If both partner A is 100% confirmed negative initially, both partners tested for HIV Elisa 3rd Generation with negative result before exposure. Three months after exposure partner A and B both test negative for 4th generation roche cobas HIV combi PT, does this exclude HIV infection for partner A. Partner A is having swollen lymphnode in neck for 1.5 months. A is male and B is female

  10. John worried

    Hello doctor sorry but again

    Had a sexual encounter with condom (not sure if it was all the way on) 2 to 3 days later started feeling intense muscle aches , and flu like symptoms. Week 2 through 6
    All the other hiv symptoms occurred (no lymph nodes).

    Tested with 4 G duo antibody at 3, 4, 5, and 6 weeks all came back negative.

    Still experiencing loss of appetite and muscle aches @
    Week 7

    Should I still be worried and does ?

    Does 6 weeks count as conclusive in America ?

    Is it possible for symptoms to keep showing after 6 weeks?

    • Your tests are conclusive. If your symptoms were due to HIV, the tests would come back positive (even if you were in the window period) as ARS is caused by antigen+antibody response in the body. Stop being paranoid and move on with your life.

  11. John worried

    Hello doctor

    Had a sexual encounter with condom (not sure if it was all the way on) 2 to 3 days later started feeling intense muscle aches , and flu like symptoms. Week 2 through 6
    All the other hiv symptoms occurred (no lymph nodes).

    Tested with 4 G duo antibody at 3, 4, 5, and 6 weeks all came back negative.

    Still experiencing loss of appetite and muscle aches @
    Week 7

    Should I still be worried and does ?

    Does 6 weeks count as conclusive in America ?

    Is it possible for symptoms to keep showing after 6 weeks?

    • You conclusively do NOT have HIV. Please see a doctor to evaluate other possible causes for your symptoms and stop worrying about HIV.

  12. Hi doctor. I had protected sex with a sex worker, no ejacuation and condom did not break. I started PEP the day after exposure, now at day 13.

    Is there any test that I can do from day 14 onwards that would be rather conclusive? As from the picture of window period above, P24 is detectable from day 14.

    And if the sex worker goes for HIV test and shows negative, is there any chance that I will get HIV? Since there is also a window period for the sex worker.

    Thank you.

    • Your initial risk would be very low. But there is no test at day 14 which is conclusive in this situation, especially with PEP on board. If she is negative, you are at even lower risk, but not zero (as there is still a window period as you rightly said).

  13. Hello doctor,i went for lapdance to a strip club 5 week ago.next day i had loose stool..so i got worried of hiv..i went for hiv rna in labcorp which was negative and alere determine combo negative at 28 and 35th day..should i stop testing.

  14. Hello, doctor/ I’m from Russia.
    I had a dangerous situation unprotected sexual intercourse with an African-American women (the condom broke).
    In my country, doctors recommend to do a hiv test after 3, 6, 12 month after contact. And it is enshrined in law.
    I took a combo test (hiv 1/2) many times through 3, 4, 6, 8, 10, 12, 14, 16 weeks. Test system: hiv ag/ab cjmbo abbott architect.
    I also handed RNA (hiv 1/2) with a sensitvity of 20 copies 1, 2, 3 month.
    All the tests are negative.

    Of the symptoms i had – a reactivation of mononucleosis, but it was all over. And got chicken pox (first time). Slightly enlarget lymph nodes, jumps temperature (36,6 – 37,2), coating on the tongue.

    If I calm down and stop to pass the tests, it seems to me that the standarts in my country are outdated?
    Has your practice, cases of late seroconversion more than 3 month?

    Thank you very much fore the help.

  15. Hi Doctor, I did 4th generation combo test at 8 weeks as it was non-reactive, I wonder if I can consider this as conclusive? and if I need to re-test at 12 weeks? Thanks!

  16. I had an exposure on April 14 th with CSW and my i used condom for both oral and veginal intercourse. I took a (Eclia) Hiv antibody 1 & 2 and Antigen P24 test on 36, 42 and 52 Days of exposure which all results are came back with Negative.

    I am afraid about seronegative. Can you confirm my test result are conclusive and any chance to turn positive after 3 months.

    I am worried a lot.


    Hello Doc,

    I asked you before about 2 cases of handjob and oral sex for two cases ,

    -First case i tested on 13 march 2016 After 9 weeks from the exposure HIV P24 Ag/Abs Combo test with Non Reactive in GCC ,

    -Second case i tested on 16 April 2017 After 22 weeks from the second exposure HIV P24 Ag/Abs Combo test with Non Reactive in GCC ,

    Only two questions ,

    Is it conclusive and no further testes needed ?

    What you mean with the Recall as per HSA ?? IS IT MEANS THE COMBO I DID TWO TIMES AS ABOVE NOT ACCURATE .

    • Your exposures do not place you at any risk for transmission of HIV in any case. Furthermore, tests at 22 weeks exposure are not affected by the HSA recall. If you are still concerned, please visit our clinics and speak to a doctor.

      • HSA RECALL

        Doc ,

        Please clarify more i am in GCC so it will be hard for me to visit ur clincs , what is wrong with HIV P24 Ag/Abs Combo test , is it canceled snd not accurate anymore ?

        First expousre after 9 weeks and It was Non Reactive

        Second Expousre was after 22 weeks and it was Non Reactive

        • The SD Bioline combo test was recalled by the manufacturer for tests done between Feb 2016 and May 2017. We have changed our combo tests to Alere from May 11th 2017. Only the p24 antigen component which is detectable from 2 weeks on is affected. The antibody component of the test is not affected. Your test at 22 weeks would only detect the antibody component, so it is conclusive. You do not have to repeat your test.

  18. Limosn

    Hello Doc,

    I need yoyr help u did had recieve oral sex from csw lady in kenya and it was un protectd on date of 2nd Nov 2016 and ejaculation was inside her mouth and then she spit it back and on her breasts and made my penis move on her breasts withthe cum on it , then we handjob each other i fingered her vagina as well withmy finger which i believe i had a small scratch on it in the same day morning and was bleeding littile and stopped after one minute max , it was not bleeding in the evening while i am fingering her , then i ejaculated on her back but there was no intercourse at all ,

    I never felt fever or rash and my temp is always between 36.9 to 37.1 .

    I have lympho nodes in both sides under my lower jaw since 4 months without decreasing or increasing , i am having some problems in my stomatch .

    I did one test one time only on the date of 17th April 2017 HIV P24 Ag/Abs Combo test that what was mention on my test with redult after 3 hours of Non Reactive .

    I asked the doc in the lab and he said the test call p24 antgien and i asked him i need the combo test and he answered it is combo and we call it p24 Ag , once i recieved the result report it was mentioned the list of the results i did as below ,

    1- HIV P24 Ag/Abs combo test after 5 and half months ( Non Reactive )

    2- virus C ( Non Reactive )

    3-virus B ( Non Reactive )

    4- tubier clean ( Neagative )

    5-Microglobulin result after 14 days ( Normal within range )

    6- my WBC is 6,300 all within range percentage .

    I am so so paranoied i got contracted Hiv , i need your advice

    Is it conclusive and finished ,
    Do i need to re test again now as i will be now 7 months since that date .

    Is it the 4th generation combo test .

    Thank u

    • You did the 4th generation combo test and it is negative. This is a conclusive result and you do not need a repeat test. You do not have HIV, stop worrying.

      • Limosn


        After you checked my above cases , what you mean about HSA RECALL,

        IS IT NOT APPROVED ANYMORE TO USE P24 Ag/Abs Combo test ,

        Shall i retest again and then what kind of test i should do now

        • The SD Bioline combo test was recalled by the manufacturer for tests done between Feb 2016 and May 2017. We have changed our combo tests to Alere from May 11th 2017. Only the p24 antigen component which is detectable from 2 weeks on is affected. The antibody component of the test is not affected. Your test at 22 weeks would only detect the antibody component, so it is conclusive. You do not have to repeat your test.

  19. lingorolin

    Hi, Please free a little my mind, I had anal protected sex on April 19 with an HIV+ (I just found out that he is HIV+) got CMIA Tested on May 16 (at that time I didnt know he was HIV+), then yesterday May 25 I found out he is HIV+ I freaked out and run to get tested again with CMIA w/ p24 and result not detected again, am I on window period until what day? Thanks!

  20. Doctor i have protected sex with sex worker. I have a blood test after 43 days exposed and results are came out HIV-1 and HIV-2 not detected. But I still experience itchy skin with rash, but after few minutes it disappear. Should I retest again?

    • Please reply as soon as possible

    • drtan

      The accuracy of the HIV test done at 43 days depends on what test was done.

      Itchy rash can be a sign of other STDs and also other non-STD related diseases. You should see a doctor to get properly diagnosed.

      • Steve

        My blood test was HIV 1 & 2 antibody test, it show not detected. Does this mean the test are conclusive or should I test again?

  21. Sir I am from India I had protected sex with prostitute,I did Abbott architect test cmia test at 28,48,60 days after exposure.it is p24 Hiv 1&2 antibody test as mentioned in report came back negative.Is it conclusive for both Hiv 1 and Hiv 2.or should I do 12th week test?

  22. Hi Doctors?
    I just screened for hiv this year 2017 fabruary 21, and i got non-reactive results, i just want to confirm/ask if do i need to retest again since my last exposure is around june 2016?

    Please i need answer(s)
    Thank u God bless

  23. Worried

    Hi doctors, 3rd march i had unprotected sex (but was protected at the point he knew was about to get things done) with a colleague. Performed a number of oral sex on him that day so next day i was down with sore throat. Shortly after i was down with slight cough and on the 10th march I experienced itchiness around the vagina area but no smelly or any kind of discharge. 11th march went to visit GP did not let him do a check on me just told him I suspect i was having yeast infection so was given oral med for that. On the 12th march i was down with cold liked symptoms with probably slight fever, slight runny nose and slight cough. Itchiness is still there but it wasn’t as bad. I’m worried, should i go for the hiv test?

    • Hi,
      Your symptoms are unlikely to be due to HIV as it would be quite early after the exposure. However, there is always a risk of STI transmission especially with unprotected sex. If you are concerned, you may come down to our Robertson Walk clinic for anonymous HIV testing 28 days after your exposure (April 1st). If you have any other symptoms such as vaginal itch or discharge, you may also come down earlier to have that assessed first.

  24. Hai Doctor.I been tested negative for HIV on the 13 week of my high risk post exposure.Can this test condider conclusive?is it need to take another test at 6 month?

    • Please direct these questions to your doctor who did the test for you. In my opinion, testing at 6 month is not necessary.

      • I didn’t see any doctor about the test..i do all the hiv test on my own.I did rapid test on the 1st week, NAAT test on the 4week, Ag/Ab test on the 7week & finally on the 13th week Ag/ab.All of this test is Negative.I read the CDC guidelines say 6month in total “to be sure”

  25. Hello Dr.Tan,

    I had sex with a lady from a Spa in Dubai, I was wearing the condom, my penis was inside her vagina when she was on top of me. when she got up, the condom was stuck in her vagina and is visible, after 48 days of this exposure, I got tested for HIV (Duo 4th Gen), HIV TriDOT – Spot test, HIV-1 DNA qualitative. All of them came non reactive/negative.

    Could you let me know, should I go for a confirmation test again after 3 months (window period).

    Thank you,

    • In my opinion your test is conclusive. Please verify this with the doctor who did the test for you.

  26. How accurate is the Alere Determine at 54 days post possible exposure. I’m still planning on having a test at 84 days. I’ve read several varying opinions. Is my negative status likely to stay the same? Thank you.

    • Personally I think it is more than 99% accurate. That is only an opinion, not fact. You should still retest.

      • So I’m assuming the accuracy issues with the Alere Determine are with the antigen and not the antibody? My doctor’s office only offered a gen 3 test. I took it at 3 weeks. He advised it wouldn’t be accurate at that time and told me I could go to a clinic and get the gen 4 test at 6 weeks and it would be as good as conclusive but he admittedly isn’t an “expert on HIV” (his words not mine).

  27. I did test elisa after 43 day and the result is negative is that enough or what I live in netherland

    • drtan

      It is certainly very indicative but it should still be repeated at 3 months to be 100% accurate.

  28. Hi dr tan,

    I had unprotected sex, after 18 days i went for a 4th generation test, and its negative. Do you advise getting tested again?

    • drtan

      Yes of course. The 4th Gen test at 18 days is definitely not 100% conclusive. It is only conclusive at 28 days.

  29. Please Dr could you reply to my question I’m so stressed.

  30. Hi docter I had a incident about 14 weeks ago.I used someone’s razor and cut myself on many places.I just wanted to know can a person catch hiv that way? He used it in the morning then I used it in the evening .I can’t remember if there was any blood on that in why I freak out.The same guy wich razor I used fingered me a week before the razor incident?Can a person catch hiv from being fingered? I was so worried and asked the guy to take a finger prick hiv test 8 weeks after the exposure and it was negative.I also got tested at week 1,3 and 4 after exposure with the p24 antigen combo and came back negative. I was still worried so I went for a pcr because I was sick and it stressed me out more but at 6 weeks the hiv DNA pcr also came back negative.For a while I was fine and then just sudden I started to stress again and went for a hiv antibody finger prick test at my pharmacy at 10,12 and 14 weeks . All 3 test was again negative. Must I test again at 6 months?

    • Please reply

    • I really do not understand your level of stress. First of all, you cannot get HIV from fingering. Secondly, you cannot get HIV from using a razor that has been used hours before. Thirdly, your partner tested negative for HIV. Lastly, and most importantly, you also tested negative for HIV. So please explain to me, with all these obvious facts that you yourself have stated, why you are still worried about HIV? It honestly does not make sense at all. Please stop being so paranoid. You do not have HIV. Move on with your life.

      • I have a sore throat for about 3 months now and a rash on my body that won’t go away that is why I am so worried and I have a headache everyday… That is the only reason why I am worried.Is the tests I did accurate at that time? Thank you for your time you are the best.

      • Sir I have done dna n other normal blood test of giv came negative. Is any chance is ther the status wil Chang plz help me I am worried I am getting married in few days

        • The accuracy of your test depends on what test you did at what duration after the exposure. You should clarify the accuracy of the tests you did with the doctor who performed the tests for you.

  31. Very stressed

    Dear Dr., I had not any sexual activity, I am married and an older guy (56). But I was to the barber’s shop than I got sick (muscle pains, sweating, weakness, throat pain) after about two months. I tested HIV antibodies rapid test NEGATIVE after 61 days from this visit. I can suspect only the barber’s razor for infection. Do I need to go for further testing? Thank you.

    • I have seen many questions about getting HIV from a barber shop. But personally I have never seen any documented proven cases. I wonder why this is such a worry. If you or anyone knows of an actual case of HIV infection from a barber shop visit, please share that with me.

      HIV Antibody tests are only officially conclusive at 3 months. So you need a repeat test even though I question whether or not you were at risk in the first place.

  32. Do, I need to take a HIV test after a deep kiss with tongues, I have a cavity that is to the gum. I have been sick since the week after the kiss.? Can you catch HIV like this?

    • Why are you so nervous about this? Kissing does not transmit HIV. Please relax and move on.

      • I guess because I have poor dental health. The internet is full of conflicting information. I will try to put it behind me. Thanks

  33. Denial

    Dear dr.
    Can ars symptoms occur after 7 week of exposure……

  34. Hi. I had unprotected cunnilingus & protected vaginal sex with a female sex worker on 12 Feb 2016.

    How high is my risk of getting infected and when should I get the rapid 4th gen combo test.?

    • Your risk is not high at all. You should get the HIV 4th Gen test at 28 days post exposure. It is actually MORE important for you to screen for other STDs like Chlamydia and Gonorrhea.

  35. Hi doc, few qn to ask.
    1) do hiv rash itch. How does it looks like.do the rash comes witb other symptoms or can be alone.
    2) i read abt the uk guideline and they said 3mths is then conclusive. I took the combo test at 5 weeks and is negative. Conclusive?

    • 3) i have throat inflamation at 8 week post exposure and pimples like spots only on my right leg which doc said is bacteria. Is the hiv related sore throat real bad as im able to drink n eat as mormal. Some website say ppl experience mild symptoms like flu. Im confused now.

      • 4) possible for the symptoms come at 8 week after exposure?
        5) possible for rash to appear on one side of the body as i read it is normally asymmetrically. Mine only occurs on right calf. No other rashes spotted.
        6) how long do the rashes last? Y do some said the ag/ab might not be detected at 4 weeks?

        • 4) Possible. ARS symptoms can appear from 2 weeks onwards
          5) Possible.
          6) This really varies from person to person. Antibody may not appear so early. Antigen appears from 2 weeks onwards, so can be detected at 4 weeks.

    • 1) Please read this http://www.drtanandpartners.com/more-on-hiv-symptoms/
      2) Combo test at 5 weeks is conclusive enough. If you are concerned, you should take an antibody test at 3 months.
      3) Again, please read http://www.drtanandpartners.com/more-on-hiv-symptoms/

  36. chemicallll

    Hello DR,
    I did PCR test at day 10 negative
    14th Day Vidas duo ultra(p24 and antibody) negative
    and 42th day Vidas duo ultra test negative.

    My question is I got cold and tonisilit infections easily( I used to smoke a lot) before I am not sure this may be considered as a weak immune system. Can my body produce antibody late?(after 42 days)

  37. Skittles

    Hello Dr.,

    Some time ago I had an exposure with a Female sex worker, we had protected vaginal intercourse and I performed unprotected cunnilingus on her, I’ve read that the risk for oral sex its extremely low, but in my situation I’ve bit myself on the side of my mouth around 30 minutes before the act, there was no blood but there was definitely some inflammation at the moment of the act.

    I did a 3rd generation blood test in a lab (Labcorp, USA) and it came back negative at 61 days (8 weeks 5 days) after exposure.

    My questions are,

    1) Does the lesion in my mouth increased the risk of contracting HIV from cunnilingus?
    2) Is my 61 days negative considered a great indicator and what are the chances of it changing to positive on my 12 weeks test?



    • 1) No
      2) 3rd generation antibody test is only conclusive after 12 weeks. Day 61 is too early.

      • Skittles

        Hello Dr.,

        thanks for the prompt response.

        Would you recommend more testing based on my risk?
        I did test for all other STD also and all came back negative.



  38. Hello doctor, is my test conclusive at 2 months 15days with alere determine HIV1/2 Ab? Am showing almost all the symptoms of HIV like slight rash,sore throat,slight cough and mouth ulcer but I tested negative at 2months 15days. Am so worried sick. Please answer. Thanks and God bless u always. My condom broke during sex with a lady of unknown status. Help me plz

  39. Please doctor, how accurate is determine HIV 1/2 Ab after 2months 15 days . My condom broke during sex with a lady of unknown status. Please answer. Tnx

  40. Hi,

    3 days back I had possible exposure. I had sex in massage parlour which was not planned. I was around less than 30 second inside her vagina when I got scared and pushed myself out. She quickly removed the condom and flushed it out before I checked the status of condom (for tear or cut). Every thing happened so fast I dont remember exact details. Now I got nervous.
    I went to one govt authorised clinic for test (within 70 hrs), but they told me that HIV test would be more reliable if I do it after 18 days or 30 days or 3 months.
    What would you suggest me to do? I am quite stressed.


    • Dr Justin Sim

      I assume now you will beyond the 72 hour mark so PEP is out of the question. This means you have 2 choices. Either wait till 10 days post exposure and do the expensive PCR RNA test or you wit for 1 month and do the rapid 4th gen combo test. Both will be accurate.

  41. Sherry Lewwis

    Hi doctor.
    I was tested for HIV last month. One of the tests was an HIV 1/O/2 antibody test and that was negative. I was also test for a fourth generation screen test and that was positive. The last time I had sexual contact was 2 years ago.
    Am I conclusively hiv negative? My doctor said so but I am still worried because of the positive fourth generation. She said it was a false positive.
    Thank you!

    • Dr Justin Sim

      It is possible that the 4th gen shows a false positive but best to be sure here. You may need another test or you may need to get the HIV PCR RNA test done as this is the definitive test for HIV although it comes at greater cost.

  42. Worried

    Dear Dr.,
    I’m a male and have been tested with Elisa 4th gen. on 18 and 47 days post exposure.
    Now I’m 10 weeks post exposure and experiencing left lower leg aching with moderate knee pain, left arm aching and somethimes aching of wrists.
    The exposure was unprotected oral and protected vaginal.
    I have tested for all STDs on 18 day post exposure.

    As I’m still experiencing above symptoms, should I retest again for all the STDs together with HIV or my tests are conclusive?

    Thanks on your advise!

    • Your achy symptoms may not be related to HIV or STD at all.
      Your HIV test is conclusive. However, it is advisable to get tested at 3 and 6 months if you are worried.
      You can repeat a STD test at 3 months if you are concerned.

  43. Hi Dr,

    I’m planning to get an HIV test after 6 and 12 weeks but am only in week 2 and am constantly thinking about my chances of catching hiv from the following 2 incidents. Both occurred last week on a trip to Bangkok. I would really appreciate your thoughts as I am reading contradicting statistics on various websites:

    I had 2 episodes of vaginal sex with a Thai street worker of unknown status. I used a condom both times but frighteningly the condom slipped both times. First time, I realised fairly quickly I think though my memory is blurry and I may have been inside her unprotected for a minute or so. I withdrew and received a hand job to climax.

    The next night I was checking the condom was on constantly due to what happened the night before. I think I noticed very quickly that it slipped. Stupidly, we reapplied the same condom and I finished inside her. No apparent rips on the condom so I’m not worried about full ejaculation inside her. I think the condom did it’s job here.

    There were no apparent cuts or leasions on my penis at the time of the incidents and I had no other STD’s before the incidents. I’m a fit, healthy male who rarely gets I’ll so I must have a good immune system. Does this make a difference? The sex worker did offer a condom to start with which I suppose is reassuring but I had my own anyway. There was no friction during the sex as far as I know. In fact, she seemed very lubricated.

    I’m scared by rumoured infection and transmission rates among Thai CSWs as well as the fact that I was unprotected, even if it was only a minute or so.

    Like I say, I will take the test but is there anything you can say to stop me worrying?

    Thank you. I really appreciate you reading and replying.

    • Even if she had raging HIV and you had full on unprotected sex with her your chance of getting infected is only 1% at worst and possibly even as low as 0.01%. That is what the real statistics say. What is actually more baffling to me is since you are so worried, why don’t you get the RNA PCR test? You are at 2 weeks right? That test is 100% accurate. You don’t need to wait till 6 weeks.

  44. Hi dr tan!

    I am in very stress please help me. Your one opinion can change my life.
    My question is that i had used electric shaver after 15 minutes of other person use and it cut my skin. My concern is that if first person is hiv + and his blood on electric shaver and it cut my skin after 15 minutes of his use can hiv be transmitted to me or virus is already killed in 15 minutes. Please reply you are luke a god for me.

    • Dr Justin Sim

      You cannot get HIV this way. Do not worry.

  45. I had a potential exposure to HIV I took a blood test around five months later it came back negative but to come in here that the person that I had unprotected oral and sex with their old partner was HIV positive could I possibly have been exposed and test results just were on a conclusive artists results were correct please cynthia HIV anxiety off of me I’m so worried now I have a boil on my private area I really need to know if I could have been exposed 5 months before I got tested in 2013

  46. Doc I had oral an unprotected sex someone bac in 2012 I tested in Dec.2013 my blood test was negative for hiv but this year in 2015 they found out that a person they was with in 2009 had hiv please tell me I have nothing to worry about because now I have a.boil on my private area an just gettin oer a really bad cold an now I have a really bad cough lingering from my cold but it’s not a dry tough I jus cough up green flem tell me I’m ok jus thinkin to much n let me know if my blood test would be accurate after five months of possible exposure

    • Dr Elaine Loh

      HIV ELISA test is conclusive 3 months. In my opinion, there is no need to repeat unless u really want to. For the symptoms that you are experiencing, best for you to visit a doctor as you may require antibiotics.

  47. Doc I had oral an unprotected sex with someone bac in 2012 I tested in Dec.2013 my blood test was negative for hiv but this year in 2015 they found out that a person they was with in 2009 had hiv please tell me I have nothing to worry about because now I have a.boil on my private area an just gettin oer a really bad cold an now I have a really bad cough lingering from my cold but it’s not a dry tough I jus cough up green flem tell me I’m ok jus thinkin to much n let me know if my blood test would be accurate after five months of possible exposure


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