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HIV latest news

Latest News in HIV

Recently got my hands on The Sanford Guide to HIV/AIDS and Viral Hepatitis Therapy 2014 22nd Edition

Here’s a summary of what’s new about HIV.

  1. PEP effectiveness / PEP Efficacy

‘Not 100% effective; seroconversion still detected in 1% of 702 exposed individuals.’

Wow. 99% is a whole lot better than the 80% to 90% we used to quote. This figure was quoted from a study done in 2005 published in the Journal of Clinical Infectious Diseases. My personal experience with PEP has been very similar. I would say 99% effective is a more representative of my experience than the often quoted 80% to 90%. However, the take home message here is really PEP is not 100% effective and should not be viewed as a ‘get-out-of-jail-free’ card.

  1. HIV risk / Risk of HIV Infection / Transmission

Female-to-Male Transmission 1 in 700 to 1 in 3,000
Male-to-Female Transmission 1 in 200 to 1 in 2,000
Male-to-Male Transmission 1 in 10 to 1 in 1,000
Fellatio 0 (CDC)

The numbers confirm what we already know. Male to female transmission is more likely than female to male transmission. Male to male transmission is high risk. I must say that the risk numbers are higher than previously quoted. However, I must add that this does not specific sex act i.e. penile-vaginal sex, penile-anal sex etc. What is interesting is that they said the US CDC quoted Zero risk of fellatio. However in another part of the booklet, it says ‘Infection risk documented in unprotected oral receptive intercourse.’ This just proves what I have been saying all along: HIV risk from oral sex is controversial.

  1. Factors that Increase the Risk of HIV Transmission

Male-to-Female Transmission Relative Risk
Oral Contraceptives 2.5-4.5
Gonococcal Cervicitis (Gonorrhea infection of the Cervix) 1.8-4.5
Candida Vaginitis 3.3-3.6
Genital Ulcers 2.0-4.0
Bacterial Vaginosis 1.6
HSV 2 2.5
Vitamin A Deficiency 2.5
Female-to-Male Transmission
Lack of Circumcision 5.4-8.2
Genital Ulcers 2.6-4.7
Sex during Menses 3.4
HSV 2 6-16.8

So if you are a man and you are not circumcised, have genital ulcers caused by Herpes type 2 and have sex with a HIV +ve woman during her menses, you really have your odds stacked against you. But the ladies really have it rough. Even a common vaginal fungal infection will increase their risk of contracting HIV. What is interesting is that there is no mention of other STDs like Gonorrhea and Chlamydia etc. There is a mention however that a woman with cervicitis has more HIV viral DNS in her vaginal secretions (higher risk for men). Since most cervicitis are caused by and STD, this suggests that if a woman has an STD, her male partner is at a higher risk of contracting HIV. Similarly, men with Gonococcal Urethritis have more HIV viral DNA in their semen. This increases the risk of transferring HIV to their partner.

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

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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  1. Peter

    Hi Dr Tan

    I have unprotected oral sex with a paid sex worker. She only done 1minute of mouth-to-genital contact and I only done like few seconds of mouth-to-genital contact but she already put on lubrication. On next day, i found out that my hand had needle injection bruises which I’m unclear was that an injection bruises. Its quite small and slight pain when I pressed on it. It does not have the kind of ouch feeling. Right now, I have headache, and neckache. Are this the symptom for HIV?

    • HIV symptoms are non-specific. However, your risk for HIV transmission is negligible. If you are still concerned, please see a doctor for a proper consult and evaluation.

  2. i have unprotected sex while she was having periods ….she don’t have HIV .Is there chances to have HIV??

  3. Hi Doctor,
    I had unprotected sex with a masseuse for 10 seconds .. I was oiled up and maybe had a couple of slow thrusts in her. She said she was clean and does not do this with clients .. she has been here for 3 years and have seen her often but this happened first time. I was on antibiotics Taxim O at that time due to a cystoscopy for cyst removal in urinary bladder done 45 days prior to possible exposure.
    I am having knee pains 20 days post exposure and a mild sore throat since past 15 days or so. No fever and no rashes

    Please advise how much should I worry and also when and what test should I get done to satisfy my worry

  4. Sarath Kumar

    Hllo sir.. Pls hlp me.. After oral sex with Gay man and spitted his cum frm my mouth. And wasshed.. I have no sores at that time.. After 10 pimples occurs in Upper chest doctor said that is pimple. Then one ulcer spot mouth and diarrhea for 2days.. Plss help me sir…. Am so much fear

    • Sarath Kumar

      Sry sir.. After 10days 3 pimples are occur in Upper chest and asual face

    • I do not believe you are at any significant risk for HIV. If you are concerned, please see a doctor and get tested.

  5. Is OHL possibile to appear 3 weeks after hiv infection,and can it cover all upper part of tongue also with sides fully covered….5 weeks constantly no changes.

  6. How bad is thrush with hiv and when are you most likely to see it

  7. Hi doctor,

    I was recently dignosed with STD after having a really bad fever and cold, about a month or less from my last intercourse, given 2 jabs and 4 pills taken immediately at the same time. The flu like symptoms when away almost immediately within the day, by the second day the symptoms were completely gone. It has been about 3 weeks since and I am still feeling breathless from time to time and worried that it might be something more severe. Do advise


    • Hi,
      The symptoms of breathlessness are unlikely to be related at all to your STD, but there can be many causes for breathlessness including chest infections, asthma, heart problems etc. and if you are concerned you should come to the clinic for an evaluation.

  8. Hi doctor,
    I had unprotected oral sex with a guy and I didn’t know about his HIV status, He did cum a bit in my mouth but I didn’t hold it but spit them out straight away, however I used mouthwash before and after performing OS. But then he told me he’s clean. My mouth was bleeding 2 or 3 days ago and I could see my mouth was fine on the day I performed oral sex.
    After that 2 weeks I hanged out a lot at night and walked under the rain for a couple days, drank some beers and the weather was pretty cold. Then when I got home My eyes were itchy, I started sneezing, having runny nose, a bit of sore throat, nausea, headache and bodyache and some itchy dots for a few days, then fatigue for 2 weeks and now they are all gone. The only thing remain is some small itchy red bumps on my hands and around my ankle, which appears one by one then gone away after a few days.

    So the question is Am I at risk contracting with HIV? and are they all acute HIV symptoms? Should I go get tested after 3 months mark? I’ve been stressed out so much and my stomach keeps hurting me, sometimes I could barely breath. Please help me out !!

    • Brian
      You would require a formal assessment by a doctor in view of the sore throat and rash that you had developed . It is good that you have recognised these signs. In my opinion throat gonorrhoea , throat Chlamydia and syphilis should be ruled out.
      I recommend you getting tested for other STDs and HIV as you had unprotected oral sex.

  9. Dr Tan

    I was the victim of some form of assault at the end of September- I am a man and he was a man. I do not fully recall what happened (due to alcohol) but started PEP within 16 hours of any possible exposure. I’m pretty sure we did not have sex, but cannot be sure. I tested negative at the start of PEP and negative at the end of it on 28th day. It is now over a month since I finished the course. In your experience, should I consider myself negative, or should I get another test now? Thanks so much for your advice

    • You definitely should get another test. I am surprised you asked this because I am sure the doctor who tested you told you that you need another test. That said, I am very confident your test at 28 days is accurate. To find out why I said that, read my post on When to test for HIV after PEP by clicking HERE.

  10. Hi doc I’m freaking out

    Yesterday I had protected insertive intercourse with a female. Unfortunately the condom we used broke. Out of fear, i went with her to get an HIV test done immediately. My test was negative, however her one was positive. The doctor offered to test her two more times, both of which were negative (suspected false positive).

    This freaked me out so I went onto PEP within 5 hours of the exposure. How is it possible that her first Elisa test was positive but her subsequent two were negative and how effective is PEP when started within 5 hours of an exposure? She is going for a full blood test soon to determine her status.

    Please help.

    • Why is it not possible? There is a chance of false positive/false negative for every test in the world. Based on your story, the first test was probably a false positive. Best way to confirm this is to send her blood to the lab for confirmatory test.
      PEP is >90% effective when started within 72 hours.

      • Her blood tests came back, she is positive. Iv been on PEP for 9 days now. I’ve kinda come to the conclusion that freaking out won’t help me thus I might as well maintain a level head and finish my course. In your experience have u ever seen or heard of any PEP failures and will 3 months testing post PEP be conclusive ? What are my chances of making it out of this situation negative ? I started my PEP course (Atripla) within 5 hours of the exposure.

  11. shirley

    hello doctor,,
    i have had unprotected sex recently with my boyfriend..about a week ago…one week later he tells me that he is positive…i went to get tested and it turned out negative…is it possible for pep to work even after one week after exposure?

    • I am afraid not. PEP only works within 72 hours of exposure. Unfortunately the only thing you can do now is wait until the window period is over then test again to be sure. Please also screen for other STDs.

  12. Williambot

    wow, awesome forum topic.Thanks Again. Really Cool.

  13. Dear doctor, i shared a drink with an HIV positive person who had sores on his lips yet i also had a bruise on my upper lip resulting from a fight with my brother. It’s 3weeks now and i have a small fever which mostly comes in the mornings and evenings. Is it a sign of ars? I also have a small headache and aa cold.

    • You cannot get HIV from sharing a drink with a HIV +ve person no matter how broken, ulcered or bruised your lips are.

      • Thomas White

        Hey doc, 1 week ago today I had unprotected oral sex with a Man (I am a Man) and he ejaculated in my mouth and I swallowed extremely quickly….

        The day after I got diarrhoea and it is still happening. Throughout the week of possible exposure I was really really really scared and searching on google trying to find answers and statistics…. When I was worrying I got muscle pain and twitches in my muscles however when I didn’t worry I was fine a completely normal….

        I have a sore throat my tonsils are enlarged but not huge they do have very little white patches on them and my tongue has a white film on it, but the throat does not feel overly bad. No swollen lymph nodes or rash (apart from a few boils due to stress I think?!?!)

        The guy I met up with said he was HIV and STD negative

        I just want to know is this because of HIV ARS symptoms or because of my pure anxiety…

        Thanks doc!

  14. Dr Sam Olwill

    Hi Dr Tan,

    Great website. However you’re interpreting the study on PEP incorrectly.

    The ’80-90%’ efficacy of PEP often quoted means 80-90% reduced risk.

    If the per-act transmission likelihood is 1%, for example, PEP will reduce it to 0.2%.

    In the quoted study 1% seroconverted; this study is one of the less convincing studies, as per-act risk is low.

    Best wishes

  15. dear doctors
    I am on pep and I dont have any seroconversion symtoms
    if i dont have these symptoms can i be a little bit more ease my mind
    how many percent of ppl get these symptoms in seroconversion
    can pep delay seroconversion?
    thanks you

    • Dr Justin Sim

      If PEP is used at the right time it has a success rate at eliminating HIV from your system, therefore you should never serconvert because the virus has been removed. However the only way to tell is to get testing after completing the course of PEP.

  16. Hello doctor is it normal to be tired while on PeP..and i dont have fever but i feel really cold these days and no sore throat, headache or rash..being very cold and a little bit of fever after 1 week exposure can be the sign of hiv

    • Dr Justin Sim

      This is likely caused by something else, anxiety, stress, concurrent common viral infection. Everyone feels tired.

  17. dear doctor,
    sorry for many questions..i just read something and it is really making me scare..It about washing the penis after hiv esposure can increase the risk…can i be infected from doing that and i am uncircumcised. Also Can hiv virus stay on my penis skin ..i wash my thing everyday so any advice on this doctor? ..i am on pep so while taking pep and washing my penis can i affect from it?

    • because i am uncircumcised can HIV virus hide in my penis and avoid pep or can it infect me from my uncircumcised penis while i am on pep ..i am really worried doctor please help thanks you

  18. dear doctor,
    I had a risky sex with a csw, where my condom slipped off in the end but i am not sure if i penetrate her because my boner was gone (no offence sir). The condom slipped off just before I stop with her. I start taking Pep in 35 hours exposure and may I ask you a few questions please.
    I started pep treatment from one of drtannpartner clinic..i want to know if all the pep drugs are the same in all clinic?
    I read the pep failure case 2 years ago and want to know if there was a failure with new pep drugs.
    Can you explain me about my risk and success rate of pep. i am really scared.
    I post of the forum too but i dont know it work or not so i post here too sorry doctor

    • and may i know anyone still success pep after 35 hours or more ?

    • The PEP drugs that we use is the gold standard recommended by the US CDC. I do not know what drugs other clinics use. The case of PEP failure that I wrote about was with using the older drugs and starting the treatment more than 72 hours post exposure. The success rate of PEP is quoted according to data as 80% to 90%. However, from my experience, it is better than that. Anyway, it sounds to me like your risk was not significant anyway. So in all likelihood, you will be fine. Let’s just say the odds are in your favor.

      • Thanks you for the reply doctor..so you have not seen any failure with the new drug?

        • and all the drtannpartners use the same new pep drugs? i started from somerset drtanandpartnets clinic..that will be all my question doctor thanks you

        • Personally I have not seen even 1 case of failure with this new regime (knock on wood)

          • Thanks you for your time doctor

          • Hello Dr.Tan,may I ask what is the new gold standard recommended PEP regimen for sexual exposure by US CDC?The one that you use at your clinics coz from the CDC site I can’t seem to find it,the only one reviewed is for Occupational exposure.Is Atripla now an old regimen for PEP?Meaning it is less likely to be effective as on the PEP failure you had previously written on?Your reply will be highly appreciated.

          • There is no real “gold standard” for PEP. We recommend medicines based on individual patient’s needs.

      • was that case fail because of the old drug and take the pep after 72 hours?

        • please doctor that case is scaring me i am sorry if i am not suppose to ask like this but my anxiety is killing me

          • Dr Justin Sim

            Washing can increase the risk of HIV transmission because it can break the skin and allow easier infection. But HIV does not ‘hide’ on your skin. It cannot survivie on your skin. It has to break through the skin and infect your blood.

  19. Trevor Bell

    Doc I had a scare I had protected sex with a sex worker but the condom broke and wen I realized I pulled out since then I’ve been a nervous reck I got tested 4 times with antibody rapid blood test once at 3,4,8,9 week after exposure all came back negative I’m about to take mt conclusive test thus up coming week will it turn positive I’ve also been having symtoms like oral thrush light colored stool with headache.

    • Trevor Bell

      I’ve asked her was she negative she told me yes but she agreed to get tested but we had a bad fall out and it never got done

      • Dude, calm down man. You are scaring yourself. Your tests at 8 and 9 weeks are already extremely indicative.

        • Trevor Bell

          But doc way do I have those symtoms I never had it before

        • I bring a old Maori new Zealand woman 45-50 years old…made cunnilingus fellatio…then she sit on my penis non erected but no condom….lean forward backward..may be glans go inside but not erected flaccid..she pretend….vaguna was wet with latex lubricant…what’s the chance of getting HIV from her…I started pep at 48 hours..no ejaculation..no inside penetration.but touch vagina clit…..help sir

          • Since you already started PEP the discussion of HIV risk now is really a moot point. Personally, from your description of events, I do not think your risk is significant at all.

  20. Johnson Anderson.

    Please doctor help me I am extremely scared and I regret, I have been crying every night. I had protected vaginal and unprotected oral sex with a girl of unknown status (but I suspect she has hiv because I saw rashes on her face and back but she told me they were allergies). I am a male, I used a condom but I gave her Cunnilingus, I had abrasions on my gum (coz I have d habbit of biting my side gums), I also have wounds in my mouth. I licked her gud and swallowed her vagina juices but she didn’t ejaculate. During sex she went dry and I licked her again till she was wet. I have an sti which I haven’t treated coz I have swollen glands in my groin. Doctor what are my chances of contracting HIV? After a week I noticed symptoms 1st of all I didn’t and couldn’t sleep at night, then I’ve had a fever for 2 weeks, my body is burning, my feet especially is on fire, it looks like I have scales on my palm, under my feet is white, my muscles hurt badly (I couldn’t move my hand for 3 days). A week later I developed swollen lymph nodes, my armpit swelled up, along with my neck and groin. I had a sore throat which has gone, I developed ulcers in my mouth. My throat burns and my tongue is on fire. Plus I had red spots on my tongue. I’m I in a window period with all these symptoms? Please I am really afraid, I used protection but didn’t while I gave her oral. I got tested a week later but it was negative. I also had diarreah for a few days, bowel movement and flatulence. What do I do? I can’t wait for the 3 months. Please.

    • The risk of getting HIV from protected insertive penile-vaginal sex and unprotected oral sex is extremely low. A fraction of a fraction of a percent. You are really freaking out for what is essentially almost negligible risk. Most likely your symptoms have nothing to do with HIV. I suggest you see your doctor about your symptoms and try not to worry so much. Get your repeat test for HIV which I am sure will be negative.

  21. I had sex with a lady,of unknown status,I had condom on but got broken twice,finally had the 3rd condom on,but a week later my dick stop working,after I had shock 3 times while sleeping @ night and stiffness of neck and hands ,two month I couldn’t sleep @ night and afternoon,I got extreme fatigue,now stomach noise,mood swing,I add sore in d gum of my teeth,and mild rashes on my body,doc what is my chances of contracting hiv?

  22. jonas dimly

    Hello .. Docter
    I am 22year male
    I had sex with sex worker .. Protected …but i also kissed her lot The very next day.. My foreskine of penies tip became red .. And little fat from tip … And its too painfull if i pull my skine backside .. And its burn too …
    And now its almost 1 week still .. I have no improvnent .. Its still same … And i git pimples type sonething near my private part and its too itching …
    Please help .. Did i am effected with std ??

  23. jonas dimly

    Hello .. Docter
    I am 22year male
    I had sex with sex worker .. Protected …but i also kidded her lot The very next day.. My foreskine of penies tip became red .. And little fat from tip … And its too painfull if i pull my skine backside .. And its burn too …
    And now its almost 1 week still .. I have no improvnent .. Its still same … And i git pimples type sonething near my private part and its too itching …
    Please help .. Did i am effected with std ??

  24. watsonSR

    Dr.tan thanks for such nice help to people.
    I am taking PEP (Atripla) (efavirenz/emtricitabine/tenofovir DF), i had unprotected vaginal sex with a prost. and I started taking this PEP after 24 hours post exposure.
    I hear people say about drug resistant virus. My question is –
    1. If i got a virus in my body which is resistant to Atripla then my PEP will fail 100% ?
    2. If the virus is only resistant to efavirenz and not to emtricitabine and tenofovir, then will these 2 drugs emtricitabine and tenofovir will be able to stop the HIV virus?
    thank you doctor

    • drtan

      1. Theoretically true. I have not heard of such a thing. 2. Yes. Either way, PEP is not 100% effective.

  25. DarrenGough

    Dr.tan you had this blog –
    which says that PEP failed. What do you think why this PEP failed? because he started PEP after 34 hours? or because he did not complete his entire PEP course? or he indulged in more sexual behaviours after taking PEP?
    I had similar kind of experience and im taking PEP , this incident made me so fearful that im scared that PEP will not work for me because i also started taking PEP after 36 hours of exposure. Thank you doctor

    • DarrenGough

      will a person starting PEP after 12 hours will have better chance of preventing HIV then a person starting PEP at 34 hours?

      • drtan

        Theoretically, the earlier you start PEP the better. In studies on monkeys, it was shown that PEP is 100% effective if started within 4 hours from exposure. I however cannot quote any specific studies that quantify the drop in efficacy between 12 and 34 hours.

    • drtan

      I do not know. I think it failed because he started PEP late. But honestly that is just a wild guess. No one would ever know.

  26. Doctor you are doing a fantastic job. Congratulations and thanks for all the support.
    I had unprotected vaginal intercourse with a girl. Im on PEP right now and im on 5th day of PEP of Truvada + efivarenz. I started this PEP 24 hours after exposure.
    My questions are –
    1. Are these PEP (truvada + efivarenz) good for preventing hiv?
    2. What is the percent chance that PEP will be effective for me? given above guideline says it is 99% effective.
    3. After taking PEP, What are my chances of getting HIV from this act of penetrative vaginal intercourse?

    • drtan

      1. Yes. 2. Some guidelines say 99%. My own experience is 99%. However, older guidelines state 80% to 90%. 3. I do not understand this question. Getting HIV is a unique probability. Whether or not PEP will work is also a unique probability. You cannot put the 2 together and come up with an overall probability. It does not work like that.

  27. Richardson

    Doctor thank you for such nice work. my problem is as –
    I had a condom breakage while having sex with a pros. I was inside her maybe 1 minute then i pulled back. I started PEP within 18 hours of exposure . I dont have any other std like herpes or ulcer on my penis. My question is –
    1. What are my chances of having hiv?
    2. What are the chances of PEP to be effective after 18 hours coz i read in study of animals that the more you delay in starting PEP , the less effective it may become.
    Thank you doctor.

    • drtan

      1. 0.1% approximate. 2. You are right. In animal studies, PEP is 100% effective if started within 4 hours. Honestly 18 hours is already very early. Most patients start later than that and they are still OK. Take it easy. I think all things considered, your HIV risk is very extremely super low.

  28. Thanx doc for your wonderful website, i want to know i started taking PEP 14 hours after my condom breakage incident. What are my chances of contracting HIV? What are the chances PEP will be effective after 14 hours of exposure? i do not have herpes or ulcers or any other STD. Thanks alot

    • The figure we give patients for PEP effectiveness is still 80% to 90%. This latest guideline seem to suggest that it is even more effective which is good. My experience has been similar with PEP working for my patients 99% of the time if started within 72 hours.

  29. I am on 24th day PEP after condom breakage, i did insertive vaginal intercourse on a pros for about 30 secs,
    1. what are my chances of getting HIV ?
    2. what test and when should i get tested? should i get tested now like hiv p24 combo test, will it be accurate for me right now?

  30. Thanks doctor, i just want to know that is PEP really 99% effective even when the source’s viral load is high?
    i started taking PEP 12 hours post exposure, my condom broke, will PEP be 99% effective for me as well? Becos i dont know the viral load of that woman

    • doctor, im circumcised, will that decrease the chance of me getting hiv? and by how much?

    • The source’s viral load has nothing to do with the effectiveness of PEP.


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