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For background- former lab tech at big tertiary place, current infection preventionist in rural shop and home recovering from surgery + sick so really exhausted.
Could use input on this situation:
The state health department did facility wide covid-19 PCR testing on our nursing home residents and staff. One resident tested positive, no one else. The resident is asymptomatic. Since none of the staff tested positive, one of our physicians is adamant it was mostly likely a false positive and wanted to do a repeat test.
My take was that while false pos are always possible, the specificity of the covid PCR tests is pretty good and false pos are much less common and false negatives are a much more common/greater concern, so if we did test the resident again and it came back negative it would be more likely the second test was a false negative than that the first was a false positive.
He stated that he’d seen a high false positive rate in PCR noted from groups like IDSA, AAFP, JAMA, and others I can’t remember. He noted upwards of a 20% false positive rate.
That’s not consistent with what I’ve seen in everything I’ve read about the performance of the PCR tests and seems more in line with the false neg rate or concerns about the false pos issue in antibody tests. But I’ve been out for surgery, so perhaps I’ve missed more recent data that’s come out?
Can you guys help me out whether you’ve seen that kind of false pos rate noted for any of the common US PCR tests? I’m in pretty miserable condition right now and not up for sifting through all the lit again, but worried they’re going to retest and try pull her out of iso early.
Thanks
Could use input on this situation:
The state health department did facility wide covid-19 PCR testing on our nursing home residents and staff. One resident tested positive, no one else. The resident is asymptomatic. Since none of the staff tested positive, one of our physicians is adamant it was mostly likely a false positive and wanted to do a repeat test.
My take was that while false pos are always possible, the specificity of the covid PCR tests is pretty good and false pos are much less common and false negatives are a much more common/greater concern, so if we did test the resident again and it came back negative it would be more likely the second test was a false negative than that the first was a false positive.
He stated that he’d seen a high false positive rate in PCR noted from groups like IDSA, AAFP, JAMA, and others I can’t remember. He noted upwards of a 20% false positive rate.
That’s not consistent with what I’ve seen in everything I’ve read about the performance of the PCR tests and seems more in line with the false neg rate or concerns about the false pos issue in antibody tests. But I’ve been out for surgery, so perhaps I’ve missed more recent data that’s come out?
Can you guys help me out whether you’ve seen that kind of false pos rate noted for any of the common US PCR tests? I’m in pretty miserable condition right now and not up for sifting through all the lit again, but worried they’re going to retest and try pull her out of iso early.
Thanks