[Question #6924] HIV TEST: HEPATITIS B VACCINE AND GARDASIL 9 VACCINE

63 months ago

Dear Doctors

I am from the UK. My previous question [Question #6914]

I had asked a question previously and I am now going to take my HIV test (Duo Test) at 6 weeks+ to move on definitely. My exposure was high risk unprotected sex with a CSW who is also a drug user. I am on day 51 past exposure right now. My duo combo test was negative for HIV at day 30 post-exposure. Following the guidelines, I am having my last test. I was tested negative for Hep B too.

My issue is that I had a Gardasil 9 shot (first shot) and a HEP B vaccine (Engerix brand) 5 days ago on the 6th of May 2020.

Is it safe for me to take my final HIV test now or should I wait more so as to avoid any cross-reaction or FALSE POSITIVE?

Can I safely take my HIV test (Duo Combo 4th or 5th Generation Assay) now 5 days post vaccinations were done (HepB and HPV vaccine as above) or should I wait for some time so as to avoid any issues or false positive?

If I have to wait, then how long after the vaccinations should I wait before taking the HIV test safely?

I am on day 51 post the exposure. Kindly note that I had two Hep B vaccines in 2014 but never got the booster one. I have restarted vaccination now on 6th May 2020 (last Wednesday along with HPV vaccine.)

For now, I have ordered my home kit from SH:24 NHS website and will collect and send my blood sample by post to the Laboratory as soon as I can take the test per your advice.

Thank you in advance. Your previous answer really helped.

H. Hunter Handsfield, MD

63 months ago

Sorry you found it necessary to return. The answer to this is simple, straightforward, and short. There are no medications or medical condtions that have any effect on reliability of timing of the AgAb (duo, 4th generation) HIV blood tests. That includes all vaccines, including the HPV and hepatitis B vaccines. The test result you already have are conclusive and no more testing is needed.

I hope this helps. Best wishes and stay safe.

HHH, MD

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63 months ago

Thank you doctor. I shall rely on my 30-day post-exposure test and move on then. I get it. Thank you very much.

H. Hunter Handsfield, MD

63 months ago

Minor correction: I thought you had had an AgAb test at 6 weeks and answered accordingly. Your 30 day result is nearly conclusive, but not quite (as I think we discussed last time). You need not delay that test become of the immunizations.---

63 months ago

Thank you for clarifying that Doctor. I shall have the test ASAP so as to be 100% conclusive to move on. Thank you.

H. Hunter Handsfield, MD

63 months ago

Thanks for the thanks. That concludes this thread.

As you likely have seen, repeated questions on the same topic are discouraged. This being your second, it should be your last about this exposure and your HIV concerns. Please don't be tempted to ask for confirmation that your upcoming negative result can be relied on. It can.

Best wishes and stay safe.

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