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HIV and Hep C coinfection window period

HIV Hep C Window Period

This is another question I see asked very often. Many people are afraid of being co-infected with HCV and HIV. After reading reports that HVC affects the HIV window period, they begin to suspect the validity of their HIV test results. Let’s find out the truth.

All this hullabaloo stems from a MMWR published by the CDC on 29th June 2001 titled Updated U.S. Public Health Service Guidelines for the Management of Occupational Exposures to HBV, HCV, and HIV and Recommendations for Postexposure Prophylaxis.

In this report, it is stated that ‘Extended HIV follow-up (e.g., for 12 months) is recommended for HCP who become infected with HCV following exposure to a source coinfected with HIV and HCV.’ In other words, ONLY in people acutely infected with HCV will the window period for HIV testing change.

So the real question to ask, if you really think this applies to you, is this: How can you tell if a person is infected with HCV?

Are there any symptoms of acute HCV infection? Most people actually suffer NO symptoms. Even if they have symptoms, it is usually mild and vague e.g. fatigue, loss of appetite, abdominal pain and rarely jaundice. So the absence or presence of symptoms is no help at all.

Click here for more Info on Hepatitis C

You can test for HCV. The common cheaper test to do is the EIA antibody test. This is frequently accurate 4 weeks post exposure but might take up to 15 weeks. And there is the more expensive HCV RNA PCR test that can be done 2 to 3 weeks post exposure. (Updated 15th September 2014)

Read more: HIV Window Period

So if all these test come back clear for HCV, we can then conclude a person does NOT have HCV infection and therefore the window period for HIV testing will NOT be affected. If any of these tests come back positive, then a person is diagnosed with acute HCV infection and the HIV window period will be prolonged.

Read more: HIV Symptoms

That said, is there a real need to be worried about HCV infection in the first place? HCV is mostly transmitted through needle sticks i.e. sharing of needles in drug users, needle stick injuries, contaminated tattoo needles, sharing razors, acupuncture etc. Less than 5% of HCV infections are due to high risk sexual exposure.

Read more: HIV related Rashes

So if you really feel that you are at risk of both HCV and HIV, talk to Our Doctors about getting tested for HCV. If you are clear for HCV, then you do not need to worry about the window period for HIV being prolonged. If you test positive for HCV then you will need to see a Liver Specialist for further treatment. Also your HIV testing window period should be extended to 12 months.

Update 10th December 2014 – The latest published guidelines have not mentioned HCV prolonging the HIV testing window period. This could be due to the fact that most guidelines now recommend the 4th Generation combined Antibody/Antigen assay as 1st line screening for HIV infection.
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  1. Hello Dr.,
    I received 2 second unprotected fellatio, 2 second protected fellatio, and then, I had 15 second protected anal sex with a female sex worker from Mongolia 3.5 months ago. After 3 months of that event I gave a test for HIV (4th generation ELISA), HCV, and other STIs. The results were negative. Could you please let me know if I need to retest after 6 months for HCV as some people may develop HCV antibody after 6 months and as Mongolian people has a high rate of HCV? How about retest for HIV? What test I can do now to make sure about HCV infection? Is HCV RNA is conclusive now?
    Thank you very much

    • drtan

      It is very rare to get infected with HCV via sexual contact. Yes a HCV RNA would be conclusive.

  2. monty 29

    Sir why these symptoms after that exposure?white coated tongue since11 months. two little bumps on throat and lot of saliva in mouth ,throat pain ,redness in throat sir?,today feeling pain in groin area what should i do sir i am saying i don’t want infect my wife .if you think my problem is psychological then why these symptoms after that episode of 10 may 2015 ? Please reply in detail sir you are not giving answer of my all questions .please don’t ignore. God may bless you thanks. i am waiting for your reply sir

  3. monty 29

    Dir i have took my yet another hiv antibody test at government hospital in India test no 20(19 antibody+1RNA pcr viral load at 7.5 months}at 342 days it is still negative but symptoms like white coated tongue,chest pain,throat infection shortness of breath still present today one little alser yellowish on top is came in throat just near tonsil and hurting little bit what is this sir
    Now which type of test i have to do sir i am living far from my wife due to my job and going to leave after few days.,sir i don’t want to infect her please please please give your valuable opinions what i have to do .
    1)can i start my sexual relations to my wife .please keep in mind i don’t want to infect her.
    2)now only fifteen day short for completing 12 months which type of test required ?
    3)if i am not infected why this all happening to me after that condome broke on 10 of may 2015 ?
    4) sir is there any possibility my result going to be change? Sir don’t say very unlikely. please give answer in yes and no.
    5)sir don’t be angry because i am asking lot of time .but i want detailed reply .you are shaving lot of lives all over the world through your web side and your hospitals
    6)should i start ART?
    7) should i have to think about CD 4 count test?
    8) when i have to take another test for hiv & which type?
    sir don’t ignore please please please reply soon i am waiting and expecting immediate reply from you great men

    • Your problem is psychological not virological. You need to see a psychiatrist.

  4. Sir if you are still in doubt which type of test required .today 11 month and 3 days after that bad day

  5. Dr why are you not replying sir?

    • Sir if you are still in doubt which type of test required .today 11 month and 3 days after that bad day and after how long you can say you are not infected at any how

  6. monty 29

    Thanks my lord Dr sii sik liong for your valuable opinions
    Sir I have made this silly mistake only once in my life and my condom broken. Sir but after 4 weeks of exposure little blister both side of my tongue and I went to Dr he prescribed me antibiotics and since than my tongue is white coated and redness in throat and also thik white sliva in my mouth , severe headache ,shortness in breath,night sweat 4-5 days in 11 months duration, sir before that incident I have never got this type of problems in my life .
    Sir I have took 18 antibody test including clia, cmia, tridot , comb/aids, rapid tests in deferent interval till 10 months and hiv RNA pcr viral load test after 7.5 months(test sensivity 20 copies per ml) result not detected .sir please don’t mind I am giving my detail again
    Sir please don’t mind you are like God for me and also like my elder brother
    My question
    1- if I am not infected why these problems are with me after that exposure
    2- sir after how long time you can give 100% guarantee you are not infected with HIV after looking my all the negative reports.
    3- sir if you are not sure which type of hiv test I have to do & after how long?
    4- can I start my relations with my wife without any protection?
    5- if this is not hiv which type of std?(vdrl -negative. 6,18,26 weeks,HBS ag – negative 11,26 weeks HCV – negative 11 weeks)
    6 – sir please don’t mind you are Gods gift for me and answer my all the questions in detail

    • The bottom line is, you do not have HIV. I am saying this based on the HIV tests you have done. See a doctor regarding your symptoms. They may be caused by some other illnesses.

      • Sir if you are not sure than I am asking which type of hiv test I have to take and after how long? Please reply immmidiatly you are confusing me .because you are not replying my each and every question. I have sent image of my tongue yesterday in your Facebook account sir please reply as soon as possible

  7. monty 29

    Thanks my lord Dr sii sik liong for your valuable opinions
    Sir I have made this silly mistake only once in my life and my condom broken. Sir but after 4 weeks of exposure little blister both side of my tongue and I went to Dr he prescribed me antibiotics and since than my tongue is white coated and redness in throat and also thik white sliva in my mouth , severe headache ,shortness in breath,night sweat 4-5 days in 11 months duration, sir before that incident I have never got this type of problems in my life .
    Sir I have took 18 antibody test including clia, cmia, tridot , comb/aids, rapid tests in deferent interval till 10 months and hiv RNA pcr viral load test after 7.5 months(test sensivity 20 copies per ml) result not detected .sir please don’t mind I am giving my detail again
    Sir please don’t mind you are like God for me and also like my elder brother
    My question
    1- if I am not infected why these problems are with me after that exposure
    2- sir after how long time you can give 100% guarantee you are not infected with HIV after looking my all the negative reports.
    3- sir if you are not sure which type of hiv test I have to do & after how long?
    4- can I start mrelationshi

  8. monty 29

    Sir please reply anyone I am going to be mad.why are you not responding great man

  9. monty 29

    Sir why are you not responding. Please reply soon sir .my tongue is still white coated and mild pain in throat & redness, loss of sleep ,frequently disentry after 11 months of exposure 3 times in 15 days
    Sir after how long we can be sure there is no hiv infection after having symptoms 4 months after exposure and persistent since then.
    2-sir which type of hiv test I have to do?
    3-is hiv RNA pcr viral load test reliable after 7.5 months of exposure
    4-if I am co infected with hcv in that case viral load test can pic up the infection?
    5- I was also tested for hcv after 11 weeks of exposurel what are my chances having hcv after condom broke
    6- can I start my relations with my wife?
    Sir please reply my every question you are my only hope

  10. monty 29

    Sir please please reply what are my chances doctors are giving deferent opinions. Some are saying till one year we can’t say anything .sir can I start my relations with my wife ?
    If I don’t have hiv why these problems are happening to me after that exposure
    Please sir reply today I have also diarrhoea and before one week disentry for too days
    And after 4 weeks of exposure also diarrhoea was for four days and gone after taking tinidazole still severe chest pan redness in throat whit coated tongue since ten months what kind of hiv test I have to do please reply sir ..give your valuable opinions in detail and answer my every question
    I am saying once again can I start my relation with my wife without protection

  11. monty 29

    Sir I have took hiv RNA pcr test after 7.5 months of exposure if in case I am not producing antibody to hiv will RNA pcr viral load test detect virus or not?
    Is I am free from hiv and all std now I have completed almost 11 months just8 days short .sir my questions.
    1-can I start my relations with my wife .
    2 – some doctors are still saying till 1 year you can’t be sure there is no hiv infection. Why different opinions
    3-if I am not infected why I am feeling lot of problems including throat redness and mild pain for 10 months
    4 -in case of hiv Is there any possibility after 7.5 months viral load undetectable?
    5 – is there any possibility my result will change from negative to positive ?

    • Relax, dude. You are spamming our website.
      Yes, HIV RNA PCR will detect the virus.
      1) Yes
      2) I don’t know who these “some doctors” are. If you are asking for our opinion, we give you our opinion. It doesn’t matter if these “some doctors” have different opinions.
      3) You do not have HIV if your HIV RNA PCR is negative.
      4) No
      5) Very unlikely.

  12. monty 29

    Sir my wbc 9200
    Hemoglobin 14.4 after 10 months am I free from HIV can I start my relation with my wife sir please pleas reply sir I am very sad
    And waiting for your answer please reply sir

    • Total White Cell Count and Haemoglobin are both NOT predictors of HIV infection.

  13. monty 29

    Sir I forgot also mild pain in left side of stomach and some time sound in stomach

  14. monty 29

    Sir please reply as soon as possible lot of thanks for your great work please save my life .please Dr tan when I will develop antibody which type of hiv test required?

  15. monty 29

    Dear sir I had an exposure with prostitute on 10 of may 2015 during sex my condom was broken ,after few days symptoms appear .1 cramps on stomach during running next day 2.body feel feverish but temperature was normal
    After 4 week little blister on side of the tongue went to Dr he prescribed antibiotics to me after that my tongue become thick and white coated now I have completed almost 1months but my tongue is still white coated and thick saliva and lot of spilt everytime in my mouth
    After 3-4 months join pain,sweating at night 3-4 times not regular .deficulty in breathing chest pain ,sleepiness (first three months and after10 month )
    Weakness in hands
    Hiv Test report 1- after 25 days clia antibotest.negative
    2- 42 days sure antibody test + vdrl test negative
    3-after 63 day triodot HIV test negative
    4-after 75 days comb/aids antibody test ictc negative + hepatitis B+C negative
    5-after 84 days clia antibody negative
    6-88 day army hospital rapid test non reactive
    7-90 days ictc negative
    8-125 -ictc negative
    9-141 days ictc non reactive
    10- 169 day ictc negative
    11-183 days ictc nonreactive
    12-206 days ictc nonreactive
    13-241 ictc negative
    14-282 days ictc negative
    15-290 days army hospital negative
    Now white vertical reshes on palm ( both hands)
    HIV RNA pcr at 7.5 months not detected (sample provide does not contain hiv one RNA) & cmia combo- nonreactive
    Vdrl-6,18,26 week negative but symptoms still present
    Sir I am married can I start my relation with my wife
    If I’m infected why I am not developing anti body to hiv every Dr sending me psychological councilig sir I am from Delhi India what can I do.please please help me am I free from hiv .can I start my sexual relations with my wife
    Please don’t ignore reply me soon after how long I can be sure there is no hiv infection
    2.what type of hiv test I have to do please reply in details I am going to die
    3 should I start ART?

    • I agree with your doctors. You need psychological help. It is not logical that you have had so many negative tests for HIV and yet are still convinced you are infected with HIV. Please go see a psychiatrist.

  16. Sir please am I HIV free I am married person of 29 year old want to have sex with my wife what can I do. How long I have to wait sir please reply

  17. Dear sir I had an exposure on 10 may 2015 during sex with prostitute my condom was broken after that my tongue become white coated tested 17 times till 8 month all the results negative including HIV RNA pcr viral load test at 7.5 month result. Not detected .
    Test include clia.tri dot.comb rapid test at ICTC.cmia combo at 7.5 months all are negative and non reactive
    Out of 17 test 12 of them after 3 months and 7 after 6 months
    Vdrl test 6 ,18,26weeks negative
    Hbs ag 11,26 weeks negative
    Hcv 11 weeks negative
    Symptoms red ness in throat no pain , joint pain weakness in hands,moisture inside the foreskin of penis , ireguler pimpes on skin am i free from all std including HIV please reply as soon as possible I am very worried

    • Based on your test results, you do not have HIV, syphilis, hepatitis B and hepatitis C. I wouldn’t say you are free from ALL STDs. There are other STDs such as chlamydia, gonorrhoea and herpes that you have not been tested for based on what you have said.
      Please see a doctor for a proper consultation if you are concerned.

  18. hello,is 6 month rapid test conclusive?

    • It really depends on a lot of factors but generally I would say it is.

      • Thanks Dr for the answer.i live in Mongolia and i dont know what kind of rapid tests are used here and how
        accurate they are.Does any rapid test detect all hiv subtypes or only brand(i.e Determine) and expensive one.Also,regarding pre-existing immune disorder,i can be sure that i dont have any if i dont get sick easily and have reoccuring infections,right?
        I got sick with hepatitis A and measles when i was a child.Does it mean that i have some degree immune-defiecency.I also read studies about rare individuals who dont produce antibodies and test continuesly negative.What are odds that i could one of those people.Thank you in advance.

        • All test brands are different. So I cannot make a blanket statement about their accuracies. I also cannot comment on whether or not you have immune disorders. You need to see a doctor to get diagnosed. Anyone can get infected with Hepatitis A and measles regardless of their immune status. There are extremely rare cases of sero-negative infections. Click here to read more.

      • hello Dr Tan, I just saw your reply and I got really worried. am preparing for Christmas down here but I am not enjoying anything cos am deeply worried about my HIV test. I was diagnosed of HCV some weeks back and am wondering how I got it. I had sex with a lady of unknown status on 25 July 2015 and I hv done 11 hiv antibody test since that time till 19 of December 2015 still negative. but I saw your post about HCV prolonging HIV test and I got really restless. I have symptoms like thrush,tingling in my hands and slight rash. please Dr Tan, am I free of HIV or should I keep testing till 12 months? my condom broke whill having sex. thanks. reply me plz

        • With the new modern HIV tests, there is no longer a concern about a HCV co-infection prolonging the window period. If I were you I would not be too worried about HIV. That said, I cannot give you medical advice over the internet. Whether or not you should keep testing is a question that only your attending physician can answer.

          • OK Dr tan. may God continue to bless you. all the test I did was with alere determine HIV 1/2 Ab, hope it’s a modern test? thanks

          • Oh yes. The Determine is a very good and reliable test.

    • hi again and thank you soooooo much for your answer.i just have another question.liver enzymes should be elevated if someone has acute hep c?if yes will they be elevated all the time in the acute phase in the first 6 months or just when someone is expereiancing symptoms?

      • Not necessarily. The best way to know if you have hepatitis C is to get a hepatitis C antibody test. There is no point looking at the liver enzymes. Lives enzymes can be elevated due to hundreds of reasons.

  19. cornilius

    Dear Dr Tan,

    pl resolve my quries:

    1. Is solid phase capture enzyme immunoassy is 4th gen test which looks for p24 and antibodies. or is there any other gen test with same name.

    2. EIA test neg after 1yr conculsive even if the person is infected with HCV.

    • Cornilius

      Dear Dr tan, Please address my queries. I wouldn’t bother you again.


  20. hi
    I had one sexual exposure with genital contact mayb a few penetration..did hep c antibody test at 5 week exposure. Is the test tell me i dont have hep c i will repeat at 3month and how risky is hep c from such exposure..i used condom but slipped

    • the test was negative.. is it gonna turn positive at 3month?

    • It is extremely unlikely to catch Hep C from sexual contact.

  21. Mike Nicco

    Hi Dr. Tan,

    I had a possible high risk exposure 18 weeks ago and I am extremely symptomatic. I received negative test results of HIV-1 RNA and AG-AB combo at week 14 and negative Hep C results at week 16 along with a negative Oraquick test. I am very nervous that I am positive because I am experiencing many symptoms like fatigue, abdominal pain, and had hiv ARS like symptoms occur approximately 2 weeks post possible exposure. Is it safe to say my results are conclusive? Or should I continue testing out to 6 and 12 months? I would truly appreciate your expert opinion as I am finding conflicting opinions on the Internet. Thanks so much.


    • As far as my opinion goes, your HIV tests are already conclusive. So my logical conclusion is that your symptoms cannot be due to a HIV infection. I suggest you see a doctor and widen your search for the cause of your symptoms and forget about HIV.

      • i have a questuon about difference between elisa and eclia.i read your post about it and it was ver useful.but i read some where that fir hep c the window period for eclia is longer cause with elisa they look for the antibodies to an antigen that appears in the blood faster than those detected with eclia.is that right?

        • You are being very specific. What you have read is that ELISAs look for IgM while ECLIA look for IgG. That is specific to the systems used by different labs. I do not think it can be used as a blanket statement.

    • hi.what do u think of 63 days negative hcv ab e.c.l.i.a method?tnx

  22. Hello doc,please I have just been diagnosed with HCV and I have teasted negative to HIV at 20 weeks. Am pretty worried that the HCV have affected my HIV test. Please doc,am I free of HIV after 10 negative HIV antibody test? Last test was at 20 weeks after possible exposure to alady of unknown status.thanks

    • The test kit was alere determine HIV 1/2 Ab. Thanks

      • Please can I get a reply? Am so worried and feeling really really down. Should I keep testing till 12 months Doc? Thanks

    • If you have had 10 HIV tests that all showed as negative, I think you can move on.

      • OK doc. I will try and move on just that there is a lot of conflicting post on the Internet. I will trust My God. Thanks alot.

  23. Cornilius

    Hello Dr, Just curious to know that if a person has done 4 negative Hiv test such as Tridot,Elisa,Immunochromaticgarphic,East after 6,7,9,13 months,also elisa Duo as mentioned above. Does this indicate that he is Hiv free, even if he may have not done hcv test.

    • Cornilius

      My last test was EIA negative after 13 months. From Ranbaxy labs. Do I have test for hcv.

      • Cornilius

        That means even if I have contracted hcv which I don’t, I know. This 4th gen test will rule out hcv and hiv .

        • Cornilius

          One last thing, does negative 4th gen test eliminate the possibility of hiv even after coinfection….

    • somebody

      is 82 days eclia hcv ab test conclusive?
      i heard that hcv rna pcr test is intermitent is that right?i want to test with pcr after 13 weeks is that conclusive ot pcr is only conclusive after a few weeks post exposure???
      thank you

  24. worried

    hello so doctor.
    plz answer me i am so worried.i had 9 week hep c anti body test but the metod was not elisa or eia.it was eclia i think.it came negative.i had liver function tests and all noraml.i had needle exposure and i had severe upper right abdominal pain and vomotting last 2 month.what is the chance i turn pos?

    • Dr Justin Sim

      Unlikely given your current test result.

      • worried

        u mean i will turn positive?

        • worried

          i did hep c ab test after 9 weeks.negative.called the lab they said it should be done 3_6months!does my reault worth anything?

  25. Arturo Diaz

    Hi again Dr, today i visited the most important institution in Mexico City (Clinica Condesa, where i was performed my last 4th gen test). I question them about HCV and the window period of VIH and they say there are no way to undetected p24 and “some” others components of the test… Their conclusion is i have not HIV. Even if they detected HCV in the future.

    They consider conclusive their testings in 45 days by Inmunoanalysis Chromatographic 4th Gen technique.

    I dont know what think. Their test and info is not accurate in mexico?

    I´m very confused. Is there any risk even when i performed 2 HIV 1-2 Ac/AG p24?? 1st 28 days after last posible exposure and 2nd 55 days after posible exposure?? What happened with p24 and all medical advances??

    Thank you so much and sorry by the insistence!

    • The bottom line is, the test you took is conclusive after 28 days. Acute HCV infection can potentially prolong HIV window period.
      Based on your description, you do not have HIV. Please stop worrying.

      • Arturo Diaz

        Ok, doctor, thank you, understood..I really need stop, this drive me crazy. Suddenly i remember to i took 20 drops of “moringa” (medicinal plant) each day since 1 month, aprox, and i´m worried again because i´m not sure if it becomes a inmunosupressor and can prolong the window or give false negatives even the combo test. Thank you so much again!

        • I do not think your plant medicine would affect your HIV test results or window period in any way.

          • Arturo Diaz

            I Just checked the calendar and i started with the moringa plant 2 days after the 1st HIV Combo test! (performed 28 days after last exposure). So, i have elements to believe are conclusive the HIV results, despite I will let you know how has result my HCV test. Thanks for your support. I really appreciated!

          • You are welcome.

  26. worrrrrrrieddddd

    Dear Drs, if I had my COMBO TEST at 5 week is negative, and HCV PCR RNA test at 7 week is negative..can I free from both HIV n HCV ? All tis test conclusive or not?

  27. Emanuel

    Hello Dr. Tan

    I did a combo (4th generation) HIV test + HCV test 8 months post exposure and it was negative for both. so please I need your confirmation (100%) do I need to redo those tests later?

    Also an important question, my worries were due because of a little injury at the barbershop when having a haircut, is it really a risk or not? I’ve searched all across the net and all people say that there is no risk that way and it was never reported like that. I need your


    • No you don’t need to repeat the tests.
      And the risk from an injury during haircut is extremely low.

      • Emanuel

        Hello Dr Sii Sik Liong

        By “extremely low” you mean that it coumd happen?! Because other people and experts say that there is no risk at all!


        • If your tests were negative, why are you still worried?
          Risks from such events are negligible. I would not say that there is no risk at all. But if you have been tested negative, you should really stop worrying

  28. Doctor i have neddle exposure,but i dont know status for my partner,i have negative hiv for 6-12-15-21 weeks and negative HVC for 19 weeks..i need your opinion pleasse.

  29. worriedinnyc

    Hey Doc,

    Here’s a good explanation of how 4th Generation tests interact with the supposed delayed seroconversion phenomenon from Dr. HHH on Medhelp. This helps out my anxiety quite a bit.


  30. Dear Dr. Tan, US CDC stated that majority of population (97%) would detect HIV at 3 months post exposure and the remaining will take longer up to 6 months. However, BHIVA (British HIV Association) stated that 12 weeks is more than 99% accurate except for those with severely compromised immune system. I have been got the last combo test at 14 weeks hence I was quite relieved, just what concerned me is about the issue of HIV and HCV coinfection. According to your site, you stated that coinfection prolongs the window period for HIV, and i found some articles which mentioned 3 health workers seroconverted at 12 months after coinfection of HIV and HCV. However, according to another medical forum MedHelp, their STD specialist, Dr. H. Handsfield stated that coinfection would’nt affect window period of HIV as the body was able to multitask producing both antibodies the same time. Besides that, he also mentioned that the 3 health workers case was filed at early 90s which using the less sensitive 1st or 2nd gen ELISA hence they cannot perform as well as the 3rd gen and 4th gen ELISA. I am not trying to suspect your statements but as a biotechnology researcher I was also interested in knowing the truth. Just to satisfy my curiosity, Dr. yo are expert in this field, had you met any case of coinfection that result in prolonged HIV window period?

    Lastly, I had a question that hope you can clarify it for me,
    1) Is Hep C antibody test conclusive at 12 weeks post exposure ? Liver function test was done at the same time as well and everything went normal. I’m quite worry about this as the symptoms I’m having now is quite similar with it (itchy skin, abdominal pain and fatigue). If it was conclusive then I wouldnt concern about my HIV window period though.

    Millions of appreciation and have a nice day ahead.

    • Good question. I have in fact added an update to the article on HIV and Hep C co-infection. This whole issue was brought about by the guidelines on occupational post exposure published by the US CDC many years ago. In that guidelines, it recommended that health care workers co-infected with Hep C and HIV be tested for HIV up to 12 months post exposure. People then took that and extrapolated it to non-occupational (sexual) exposures which should not be the case in the first place. The guidelines on HIV PEP (occupational and non-occupational) and HIV lab diagnosis published by the US CDC, ASHM, BHIVA, European Guidelinea, Canadian guidelines, New York guidelines have all NOT mentioned Hep C and HIV co-infection at all. Notably, in these guidelines, the Combo test is now recommended as 1st line assay as opposed to the antibody test. So I completely agree with Dr Handsfield that the problem is not with a biologic response. The problem is with testing technology. So now that the new guidelines are recommending the Combo test, Hep C/HIV co-infection is not longer an issue. The Hep C antibody test is really as good as conclusive at 12 weeks. Some articles say 16 weeks but I think they are just being ultra-conservative.

      • Dear Dr. Tan, thanks for your prompt response. I also found out that Dr. Frascino from The Body also stated that body was able to multitask producing antibodies together and delayed seroconversion should be disregarded. Unnecessary anxiety can be unwarranted as if the misleading information was corrected.

        Dr, axcoeisnf to your clinical experience and knowledge, most patients who got transmitted with acute hepatitis c, most probably the antibodies test would show up average by how many weeks? By the way, I have a point that need justification. Hep c is not really considered an std but it CAN be transmitted if sexual exposure involved blood. If a person’s exposure is only receiving oral sex or other non penetrative activities, blood wouldn’t be present or in miniscule. By right, the risk of transmission is virtually zero or negligible? Correct me if I was wrong. Thanks Dr.

        • Hepatitis C is classified as an STD. But you do realize this classification is very artificial. You can catch the flu from someone via sex but nobody ever said the flu is an STD. Most people who are infected with Hep C can have detectable antibodies by 4 weeks. The risk of contracting Hep C via sexual exposure is really next to zero. It is more spread via needle sticks injuries, drug abuse, organ transplants, blood transfusions etc. The only time Hep C transmission via sex is significant is in the sub-group of HIV +ve MSM.

  31. Hi doctor, can it be said that with a rapid combo test done. It would also certainly detect Hiv even if the patient has a coinfection of Hcv?

  32. Hello doctor, sorry I had to asked u this , I have tested negative for hep c at 4wks post exposure …… However today is my 76th day, waiting for my final 90 day hiv retest- I have previously tested negative for hiv at both 28 and 45 days…. I want to clarify that do I have to retest again at 15 weeks? Cause u mention that hep C may take up to 15 weeks…..

    • What kind of exposure was it and what kind of Hep C test was it? Honestly if it was a sexual exposure you should not even be concerned about Hep C.

      • It was a protected sexual exposure dr….I do not know what test but the hepatitis test was conducted at your clinic at Robertson at 28 days post exposure negative , can I ask if do I still have to wait? Sorry for your inconvenience and pls reply this question doctor…..

        • Stop worrying about Hep C. You are not going to catch it from protected sex. And you have already screened for it.

          • Hello drtan.

            I have unprotected vaginal sex once with csw and my ag/ab cmia hiv screening test non reactive for 26 and 37 day. I have ask this at your q&a forum and it good as conclusive.than i found this forum.should i worried about hep c.im not iv drug use.the only injection i have at clinic or hospital and i am sure that not the problem.

  33. prashant

    Dear Dr Tan,
    I am from India, I am male I had unprotected oral sex and vaginal sex(I wore condom but I don’t no whether it was broken or not )with a prostitute on 31/9/2013 till then I am worried a lot…..I got tested only for hiv after 28 days(p24 antigen and antibody test)It came back negative…….I got tested for hiv 14 times and hcv 2 times all were negative recently after 9 months I got tested for hiv(p24 antigen and antibody test),hcv(antibody test) and hbsag all were negative…my concern is I am facing problems with cold ,cough and throat pain regularly……… do I need to get tested for hiv and hcv after 12 months……please help me…….

    • You do not have HIV. Your tests are conclusive. Let it go.

  34. candawlan

    hi doctor i have hepatitis b for long so this disease can delay hiv window period i do ARN pcr at 60th day of expose ? please answer i worry so much

  35. Morinaga

    Dr tan, im a gay male and had unprotected sex oct’2012. Got tested in your clinic and the result is negative. March 2013 got tested again, and result is no hiv again. Does this mean can stop worrying? Really will wait for your answer. Thanks

  36. is it autoimmune disorder can effect hiv window period.eg diabetes can prolonged window period up to 6 mths

  37. Dear Dr Tan,
    I made quite a lousy mistake. I am female and had a one night stand with a person who had invisalign braces. No visible blood in his mouth then but he did a 10 second brief oral sex on me. Now, i have had flu symptoms for 9 months! Tested positive for HCV at 4 months. Negative hcv rna pcr one month later. Tested for HCV at 8 months. Negative. All the while, tested for HIV antibodies. All negative up to 9 months! Going 2 test HIV 1 and 2 by pcr and hcv at the end of Sept (10 months). I suspect, he had both viruses in his blood when he went ‘down’ on me. If these tests come back negative, you are saying that i should test both again at 1 year (in 2 months)? Very concerned. Thanks!!!

    • All you had was oral sex? Then no risk of HIV. HCV serology tests have a high rate of false positives. A negative HCV RNA proves that. I see no reason for you to be worried. Your symptoms are likely unrelated. Please ask any follow up questions on http://www.askdrtan.com

  38. Hello Dr.Tan,

    Had a -ve (Anti-hiv 1 and 2) and p24 at 18th month after exposure.

    my diff.lymphocytes count was 20 % ( Ref : range 20-40 %). All other CBC parameters (WBC/RBC etc) were in normal range.

    3 months back it was 21% and i remember 20 months back it was around 37 %.

    Should i be worried with that value (20%). i have taken 3 antibody test at 1 year / 15 and 18th month resp after exposure all came -ve.

    I am deeply worried if in any case my body has not generated antibody to be detected by test. Also i am expecting a baby next month and my wife tested -ve during her 3 months test.

    Please let me know your thought on this.

  39. Hye doctor,
    What else other than hep c that might delay seroconversion?

  40. negaman

    Thank you, Doctor!
    By the way, why would not you take a small fee for answering all those questions! You must be such a busy man, i think it would be very right!

    • Hi negaman,

      Thank you for the suggestion. Perhaps in the future I might. But right now, I actually enjoy communicating with people from all over the world and helping in any little way I can. Taking money for it seems to demean the entire project a little. If you find what we do here meaningful, please help spread the word.


      Dr Tan

  41. negaman

    Dear doctor!
    I tested negative by hiv DUO at 12 and 13 weeks, and also HCV negative at 12 weeks. I never had any symptoms of either of the deseases. Can i assume i am HCV and HIV negative now?

    • Hi negaman,

      You do not have HIV or HCV.


      Dr Tan

  42. Dear Dr.Tan,

    I had following two hiv tests after an unprotected sexual contact with sex worker (Date: 11th Sep 2010)
    a) elisa test at 1 year = Negative (Date : 22nd Sep 2011)
    b) 15th month (MEIA / P24) = Negative (Date : 20th Dec 2011)

    After few weeks after 15th month testing i began to feel pain in both my underarms. I am feeling scared and fearful, would this be a delay seroconversion.

    Please let me know if my tests are conclusive

    Kindly advice

    • Hi Pras,

      Your tests are conclusive. You should see a doctor about the pain in your underarms.


      Dr Tan

      • Dear Dr.Tan

        Does psoriasis or any other skin infections affect HIV antibody generation and their antibody test results.


  43. Wow this is very confusing dr first of all hcv and hiv are transmitted in almost the same way possible if you have sex unprotected with an hiv hcv person u might catch it so y is the test 6 months why not just say 12months because at leaat30% of hiv pe has hcv too. I’m saying this because I just tested today at 6 months negative omg my hearts wear rejoicing till I seen u said u should wait another 6

    • Hi musa abioye,

      Please read the article carefully. I never said you need to wait another 6 months. If you suspect that you might have been exposed to HCV (please note that only 5% of HCV cases are from high risk sex, the rest are from needle related injuries or drug use), then you certainly should screen for HCV. If you are tested positive for HCV then the HIV window period is extended. Please also note that all these recommendations are actually for health care workers who have suffered needle stick injuries. Whether or not the same advice applies to non-occupational exposure to HCV and HIV we really do not know. The most prudent thing to do is discuss your need for HCV screening with your doctor.


      Dr Tan

  44. Kevin Blake

    Hi Dr. Tan,

    Can I assume that I am free of both HIV as well as HCV with negative antibody tests for the former at 3 months and the latter at 18 weeks? I’ve read that in fact the antibody production for HCV can be delayed if you have been infected with HIV. Now, in case of a coinfection with both viruses which one should show first? Somehow it seems to go in circles.



    • Hi Kevin Blake,

      Yes I agree it is confusing. If you look at the recommendations by the US CDC on management of Health Care Workers who have been exposed to HCV and HIV, its states that follow up for exposures to HCV should be Anti-HCV Antibody tests and ALT (Liver Enzyme) for 4 to 6 months. OR if earlier diagnosis of HCV is required then HCV RNA PCR for 4 to 6 weeks. IF HCV tests confirm the presence of HCV infection, HIV Antibody follow up test should be extended to 12 months. There is no mention of changes to the HCV follow up protocol if a patient is diagnosed with HIV. Do not forget that this is all recommendations for Health Care Workers who suffered finger prick injuries from needles contaminated with the blood of patients known to have HCV and HIV. This has been extrapolated to scenarios of non-occupational exposure but do the same rules really apply? We do not know. So as doctors we try to evaluate each case according to their own merits and recommend tests as appropriate. Not everything is so black and white in medicine. As for you, I am sure you are free of both HIV and HCV.


      Dr Tan

  45. Kevin Blake

    Hi Dr. Tan,

    Does the extended window period also apply for the HIV PCR DNA test or only the window period for the antibody test?


    • Hi Kevin Blake,

      Great question. All tests. But most studies are based on the antibody test.


      Dr Tan

  46. Dear Dr Tan
    I will go to General Hospital next week friday 16 December 15 weeks post exposure.
    My country testing HIV ,VDRL And Hepatitis ABC at General hospital are Free Of Charge. If at Private clinic testing HIV VDRL AND HEPATITIS ABC the Total not more than $40. Hiv p24 $83 only.:-P
    I need your professional opinion I did Hepatitis C 5 weeks post exposure NEGATIVE. If I testing Hepatitis C again at 15 weeks it will become POSITIVE?
    Thank you

    • Hi miao,

      That is really cheap. Healthcare in Singapore is much more costly. I am sure you do not have Hepatitis C. Stop worrying.


      Dr Tan

      • Dear Dr Tan
        I just received my result
        Hiv 1 and 2 Ag-Ab(EIA) Non Reactive
        Hepatitis C virus Ag-Ab(EIA) Non Reactive
        Vdrl Non Reactive
        我在这里祝福您圣诞节,新年快乐。还有祝福您生意兴隆身体健健康康,您的 baby boy 快高长大,健健康康。我明年会去新加坡游玩。


  47. Dear Dr Tan
    I did Hepatitis C Virus Ag-Ab (EIA) 5 weeks post exposure Non Reactive.
    HIV 1&2 Ag-Ab(EIA) Non Reactive 5 weeks post exposure
    HIV P24 Antigen 4 weeks post exposure Non Reactive
    Can i assume HCV test again at 3 months Positive,so the window period for HIV p24 testing 4 weeks post exposure will be affected?
    Waiting your reply,thank you.

    • Hi miao,

      Oh dear. I didn’t know this article will make you start worrying again. Technically speaking, if you test positive for Hep C then the HIV window period will be affected.


      Dr Tan

      • Dear Dr Tan
        Thank you so much your reply, today is 99 days post exposure,I will testing again Hiv Antibody Test ,Hep C and VDRL to clear my doubt. I hope my Hepatitis C turn out NEGATIVE. If negative I have no doubt my test I did before and I will also do syphilis test.
        I will share to you if Good News.

        • Hi miao,

          These test will certainly put an end to all your worries. I’m sure they will all turn out OK.


          Dr Tan


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