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Three COVID-19 tests, three results; chasing answers during a pandemic

KSAT reporter Garrett Brnger asks the experts about his own conflicting test results

SAN ANTONIO – Ironically enough, I got my first COVID-19 test, hoping to get some peace of mind.

The free testing for asymptomatic people seemed like a good way to make sure I was protecting the people I work with and interview. But three days after I dropped my swab at the Cuellar Community Center, I had three different test results from three different tests and more questions than answers.

Having reported on the pandemic for months now, the fact that COVID-19 testing isn’t black and white doesn’t come as a surprise. Several different diagnostic tests are available locally -- whether “gold standard” PCR tests or the rapid antigen tests -- and like any test, none of them are perfect.

False positives and false negatives are possible -- to varying degrees and depending on the test -- and estimating the best time to get tested can make the process harder.

For me, there was no specific reason to believe I might be sick. I just wanted to be proactive. So on Wednesday, Nov. 11, I took advantage of the free PCR tests the city and Community Labs offered for people with no symptoms.

Intended to detect COVID-19 patients before they could spread the virus too widely, the Community Labs program offers a 24-hour turnaround. With just a few questions to answer and a couple of seconds of swabbing my nostrils, I thought I would have answers soon.

Instead, I got a message the next evening saying my test was “inconclusive.” I later learned my sample was one of 108 from both the Cuellar and Ramirez Community Center locations that had an issue with the liquid in which the swabs are transported.

Because of the problem, Community Labs wasn’t able to test the samples.

Community Labs is still investigating what happened.

At the time, I knew the “inconclusive” result was something to do with the test and not my sample, but I was concerned about not having a straight answer.

So, though it’s a test meant for symptomatic people, I decided to get a rapid test through a Texas MedClinic location. Having no symptoms, I got my nostrils swabbed and quickly went on my way, not even needing to wait for the results or a visit with a physician.

I was almost home by the time I got the call, though. My test was positive.

I immediately started my 10-day isolation in my room, putting on a mask anytime I went anywhere else in the house to protect my roommate. The station, though requiring me to isolate and stay away from work, also asked me to get a PCR test to confirm the rapid test results.

And so, still with no apparent symptoms, I got another PCR test on Friday -- this time in the form of a self-administered oral swab offered by the city -- also at the Cuellar Community Center. The results of this third test came back the next afternoon with a third outcome -- negative.

Super.

I had no clear answers from the tests and still no apparent symptoms. Like many people, I agonized over the smallest twinges in my body, debating if they were one of the many possible COVID-19 symptoms.

“Was that headache related to COVID-19,” I wondered, “or just from the leftover Halloween candy I had been stress eating by the pound?”

With no telltale fever or coughing, aside from a few following the oral swab test that had required me to cough, I couldn’t know for sure if I was sick or not.

I still don’t.

SO WHAT GIVES?

The first test result is easy enough to discard. “Inconclusive,” in my case, was just shorthand for “didn’t run the test.”

The second test -- the positive one -- is more difficult to puzzle out.

The antigen tests Texas MedClinic uses, not to be confused with the “antibody” test that can find traces of past infection in your blood, are supposed to have very reliable “positive” results. They may miss some infections, but Texas MedClinic’s Chief Medical Officer Dr. David Gude says he would be “very confident” in the results when they come up positive.

There have been reports about false positives from these tests, though, and Gude said that while the possibility of my test being a false positive would surprise him, it’s not “shocking.”

“I think this just serves as a great reminder to me -- and now to you as somebody who’s been covering this story extensively -- that false positives are a real thing. They happen to real people, and then we end up making real decisions based on information that is not correct,” Gude said.

There’s still the possibility the test result is correct, and the third test, the negative PCR, is the incorrect result.

Dr. Junda Woo, San Antonio Metropolitan Health District’s medical director, pointed out that timing is an issue.

“The ideal time, according to most of the research, is somewhere between five to eight days after your exposure,” Woo said. “But even on that eighth day, there’s only an 80% chance that it will come out positive, even if you actually do have the infection brewing.”

However, without a known contact or symptoms, Woo said a negative PCR result obtained within two days of a positive antigen test would mean the antigen test was likely incorrect.

I’ve since gone for a fourth test -- once again with Community Labs -- to settle the question for myself. But whatever happens, I’ll be riding out the full isolation period, just in case.

After all, I still have Halloween candy left.

For information on testing, including free locations, click HERE.


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