Dear doctors,

I would like to ask a question regarding a situation that has been giving me a lot of anxiety. About 10 weeks ago, I met a girl from another college in CA. She is 23 years old. We decided to have intercourse and I made sure to use a condom for protection. Prior to engaging, I asked about her status and she said she is STD-free. Through the end of the encounter, the condom broke. the last time I saw it intact was 1-2 minutes before I ended penetration as soon as I saw the tear. I managed to ask her again about her status and she insisted that she was negative for everything. the risk would be from insertive vaginal only for about 1-2 minutes

Because I was very anxious, I went to the ER the next day and I was started on PEP (Truvada + Isentress) at 30 hours after exposure. I took the medicine for 28 days and did not skip any dosage. At the end of PEP, day 29 after exposure, I tested with fourth generation Ag/Ab and it came back negative. I also tested for PCR RNA and it also came back undetected (40 was the lower limit on it). 30 days following last dosage of PEP and about 59 days after exposure, I tested again using a fourth generation test Ag/Ab and it came back negative. My doctor (who is an experienced HIV professional) informed me that my results are conclusive at this point and that no further testing is needed. I asked whether I could resume relations with my HIV negative partner and he said I should be in the clear. Because I was a bit skeptical, especially due to the CDC guidelines, I called another clinic in San Francisco and spoke to their PEP clinician. the response was the same, that my tests are conclusive. I also got the same answers in medical forums I posted in.

P.S: I tested negative for Chlamidya, Gonorrhea, Syphillis, and all kinds of Hepatitis. 

4. Have you seen a test result change on a fourth generation between week 4 and week 6 post-exposure/post-pep?

thank you.

My first two reactions are to congratulate you for you use of a condom for a new, casual sexual exposure (even if the condom later failed); but also to advise that this was much too low risk an event to need PEP. The condom intent was a good one in regard to STIs, but the chance any particular 23 year old female university student in the US has HIV is very low, probably well under one chance in several thousand. I would have not prescribed PEP in this situation. (The chances for other STIs was higher, but it's good to hear you tested negative for more common STIs.)

But what's done is done and we need to deal with it. But here too, all is well. I agree almost entirely (but not quite) with the doctors you have spoken with about your post-PEP test results. Almost certainly you do not have HIV -- both because the exposure risk was almost zero, and the reliability of your test results. The only problem is that there has been little actual research on time to reliable test results following PEP. Probably the AgAb results 30 days after the exposure are conclusive, but most experts say the results may not be conclusive until 6 weeks after completing PEP; and a few say 3 months. In absence of conclusive data, it is difficult to be sure. But if you want a final test that would meet most experts' views, get tested again in a couple of weeks, i.e. 6 weeks after the last dose of PEP drugs.

Those comments pretty well cover your three questions, but to be explicit:

1) Your results probably are conclusive, but it can't hurt to have a final test in a couple more weeks.

2) There is no realistic chance you have HIV or will ever test positive.

3) Had somehow I been in your situation, I would never have stopped having unprotected sex with my wife. You certainly can resume normal relations at this time.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

Per your advice, I will opt for one more test to close this chapter. Really hoping it comes back negative because at this point, I am still very worried even about a very slight chance. What's causing me a lot of anxiety is the difference in information I have been receiving. I had even called the national PEP line and the clinician told me that my results are 99.3% conclusive but they need to test me more to make sure that I'm not the outlier.

Now, that I hear that my realistic chance of acquiring HIV from that exposure is essentially 0, I'm very much relieved. The last curiosity was, in your experience, have you seen any fourth gen tests change from negative to positive between week 4 and week 6, pending no further exposure?

thank you again, doctor!

Question 4 apparently arrived while I was preparing my initial reply. The answer is no. Even in far higher risk situations than yours, I have never seen anyone whose test became positive once a 4 week AgAb result was negative, with or without PEP.

Unfortunately, I have some lingering anxiety and a worry from a potential change in my future testing results, especially due to me being overloaded with information online that is not completely consistent. 

I did consult previous PEP threads in the forum and I saw that previously you and Dr. hook used to say that 4th gen tests AgAb were conclusive any time 4 weeks after the last dose of medication. I also saw that the recommendation changed again about two years ago to that time window being at 6 weeks after last dose.

1- Would you be able to comment on the reasons behind such change? Have there been any cases of PEP failures that motivated such change with people seroconverting 8 weeks after exposure?

2- With regards to my situation and given your statement that there is no chance my test results change, do you recommend further testing or should I consider my results conclusive? I'm currently very anxious that another test can put a lot of stress on me, despite it being negative is probably the best way for me to calm down.

I also realize I exhaust my follow-ups with this message so I will be sure to start a new post if needed. I really appreciate your help and support in this time of significant anxiety and stress for me.

I trust you see the inconsistency between your opening statement and the additional questions! Perhaps it will also help you to know that in the 15 years of this and our preceding forum, with thousands of questions from people concerned about catching HIV, not one ever turned out to be infected. You will not be the first! If and when it happens, it will be from a genuine high risk event, not a trivially risky event like yours, and certainly not from someone who took PEP.

2) With odds you have HIV perhaps around one in 25 billion, which means zero for all practical purposes, what do you think I might advise? Isn't it obvious? From a medical/risk standpoint, I already said you never needed testing to start with. Whether you feel you need yet another test beyond 6 weeks is entirely up to you, if you would find another negative result reassuring. But that's the only reason-- for reassurance.

Please do not start another question. If you get tested with a negative result, there will be no point:  we will just agree you don't have HIV. But I'll make this deal with you:  in the exceedingly unlikely (virtually impossible) chance another test is positive, please post a new comment to tell us, and we'll refund your posting fee.

I do hope the discussion has been helpful. Best wishes and stay safe.