However, STI tests aren’t perfect.

Itispossible to get a negative test result and still have an STI.

But very often, that’s the case.

Couple consulting doctor in his office

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Some knew about their diagnosis, while some did not.

There are several potential reasons why STI tests aren’t infallible.

This, unfortunately, may not be true.

Some providers don’t regularlyscreen patients for STIs.

It’s also easy to confuse tests like aPap smearorpelvic examfor an STI test.

If you have a known exposure, mention it.

All of this can highlight the need for specific tests.

Antibodies are specific proteins your immune system produces in response to infection.

Almost no test is going to be perfectly able to determine whether or not someone is infected.

Still, both false positives and false negatives can be a problem.

2014;4(2):114122. doi:10.1212/01.CPJ.0000435752.17621.48

Centers for Disease Control and Prevention.HIV testing.