Hello Doctors!!

I had unprotected sex on 28 Nov 2024. I tested for HIV using 4th-generation tests at 23 days ,46 days, 8 months, 8 months 20 days, and 1 year 10 days - post-exposure, all negative. I have had no health issues or symptoms in the past year.However, after reading about rare seronegative HIV cases, including recent reports, and a forum thread here where a NAT test was advised despite negative 4th-gen tests, I’m feeling anxious. I have never had an HIV NAT/PCR test.

My questions:

1. Is it possible for a healthy person to remain 4th-gen negative long after the window period but test positive only on a NAT?

2. Should I get a NAT test for HIV-1 and HIV-2 ?

Welcome to our Forum and thanks for your questions.  I hope that my assurance that you do not have HIV will allow you to begin the New Year without concerns.  HIV following a single encounter is quite rare.  Most people do not have HIV and unprotected vaginal intercourse with an infected, untreated partner transmits the infection on average less than once in every 2000 encounters (I.e. there is a more than 99.9% chance you would NOT be infected).  Further your multiple tests have been taken when results are reliable.  ---

Thanks a lot for answering my question, Doctor .A very happy new year to you as well!!
 I got worried after reading a thread here - titled - [Question# 13615] HIV Negative, AIDS symptoms- in which Dr. Handsfield had suggested someone to get a NAT test done even after his 4th gen tests were negative. It would be really helpful if you could comment on that. That made me to worry and think that what if I develop some infection someday, and then my diagnosis is done using NAT. Do you think this is a realistic scenario for me? Another query which I had is that even in seronegative cases, can the 4th gen test detect HIV-1 infection since it checks for p24 antigen as well - and they won't become undetectable if antibodies are never formed. It is also causing me to worry about HIV-2 since it is detectable only through antibodies in a 4th gen test and will be missed in a seronegative case.

In 13615 it appears that Dr. Handsfield suggested a PCR test for a client with serious symptoms solely to “ close the loop” for an anxious, ill client.  He repeated indicated he was confident that the PCR, like prior 4th generation tests would be negative.  I agree with this and really see no scientific need for further testing.  As we have said repeatedly however, if your level of concern is high and you need a PCR, then do it.  If you choose this route however, I urge you to commit to accepting the result which I am confident will show once again that you are not infected.---

Hi Doctor!! my doubt arose because of the following statement by Dr. Handsfield in that thread- "That said, it does seem surprising your doctor(s) have not requested an HIV RNA PCR test, which normally would be done in situations like yours." 
I am sorry if I am misinterpreting it, but it seems like he is asking to get a PCR RNA test done even after negative 4th gen test since the person is ill. Reading this, I thought that if I become ill and develop some opportunistic infection someday, then I might fall in the same category in which I might be advised to do a RNA PCR test for my diagnosis. I am extremely sorry if my questions are coming across as repetitive, but the thought that I might be a rare case who can be detected only by a NAT test is making me very anxious and an expert view on why that can't be possible will really help me. I would be really grateful if Dr. Handsfield's statement and my position could be explained. Sorry for the inconvenience caused and thanks a lot for helping.

You are being repetitive.  As I explained above, Dr. Handsfield was explaining that in situations in which the patient is clearly sick (apparently you are not) a clinician in MIGHT order an HIV PCR test in addition to a 4th generation test.  As I also said, he said (more than once!) that the he anticipated that the PCR test would be negative, as do I.  You are over interpreting Dr. Handsfield's statement---