Took two oraquick tests at home 108 and 110 days post-exposure. Both negative. My anxiety is making me doubt their results due to published false negative rates. Also, as I showered right before taking the first test at 108 days, I’m now concerned I had gotten water in my mouth while showering. Thus…

1) How confident can I be in my results? What accounts for the false negatives?

2) What if I did get water in my mouth before the test (within 30 minutes of taking). How much does that really impact results? Both showed control line clearly.

Thank you for your time!

Indeed, the Oraquick is our least favorite test as it occasionally misses infections detect by other tests.  Acknowledging that however, in published studies, there are no significant differences between the OraQuick and other tests for HIV.  As such, results are considered conclusive at any time more than 8 weeks following exposure.  Thus both your 108 and 110 day tests are conclusive.  The likelihood that a test would give falsely negative results on two occasions is virtually zero, particularly if the control line, which is in part a quality control measure was reactive.  

Water in your mouth from the shower would not adversely effect the performance of the test

I hope my comments are helpful.  You can have confidence in your HIV test results.  EWH

1) What contributes to the published oraquick false negative rates? Is there still a risk of a false negative outside of the window period?

2) Oraquick instructions indicate no food nor drink 30 minutes prior to testing. My possibility of having shower water in my mouth (not sure it happened, can't recall, and if so, it was not swallowed) does not fall within that directive. Your response would indicate this possible happening does not have any impact on my test results? In your practice have you ever come across a patient with a false negative from drinking water within the 30 minutes time frame?

Thanks again for your expertise!

Eating and drinking large amounts of liquid and theoretically diminish the accuracy of the test however IF you swallowed some water, the amount would be slight.  As I said above, the positive control lines verify that the specimen was appropriate and the test mechanism worked.  Even if somehow swallowing shower water impacted your result (and I remain confident it did not), the other test was not performed in a questionable situation.

I urge you to believe your test results.  EWH