[Question #3250] STI''s window period

37 months ago
Hi there. I have asked questions before and have one somewhat new question. 

I had asked about NAAT window periods in the past for chlamydia and gonorrhea. We now have a discreet online test we can do in BC Canada and they use either urine PCR or urine antigen rather than NAAT.  What is the window period for those 2 tests for gonorrhea and chlamydia. I would like to go at 14 days post exposure.  Is that enough with those types of testing?  

Thanks so much!
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
37 months ago
Welcome back to the forum.

I recommend against the antigen test, which is more likely than NAAT both to miss an existing infection or to be falsely positive. NAATs clearly are superior. (PCR is one kind of NAAT.) We discussed the NAAT window periods for gonorrhea and chlamydia in your previous thread 7 months ago, 2-5 days (probably 2-3 days for gonorrhea and 4-5 days for chlamydia). Testing 2 weeks after exposure is fine for either infection.

Regards--   HHH, MD

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37 months ago
Thank' so much Dr. H!
36 months ago
I just want to confirm that these window periods are fine for urine NAAT.  Urine is do much simpler than swabs. Thanks again!
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
36 months ago
These windows are for NAAT, both urine and vaginal swabs. Urine testing misses a small number of infections that are detected in vaginal swab, which is the preferred specimen in women.

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36 months ago
Thanks very much!