Unreliable COVID-19 tests might be a problem

Pandemic

Uh oh. South Korea is finding some patients thought to have been cured of COVID-19 have apparently been reinfected:^[1]

Fear of re-infection in recovered patients is also growing in China, where the virus first emerged last December, after reports that some tested positive again – and even died from the disease – after supposedly recovering and leaving hospital. There’s little understanding of why this happens, although some believe that the problem may lie in inconsistencies in test results.^[2]

The article does not make clear what sort of “inconsistencies” are being found in the test results,^[3] however, false negatives, such as those anecdotally reported previously,^[4] might account for the phenomenon.

“A patient is deemed fully recovered when two tests conducted with a 24-hour interval show negative results,”^[5] but if the negatives are false—and repeatedly so—then the patient will have been incorrectly “deemed fully recovered” when s/he is in fact still sick and s/he indeed might die.

This is another reason you need reliable tests.

Kyunghee Park, “Coronavirus May ‘Reactivate’ in Cured Patients, Korean CDC Says,” Bloomberg, April 9, 2020, https://www.bloomberg.com/news/articles/2020-04-09/coronavirus-may-reactivate-in-cured-patients-korean-cdc-says

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1. ^[1]Kyunghee Park, “Coronavirus May ‘Reactivate’ in Cured Patients, Korean CDC Says,” Bloomberg, April 9, 2020, https://www.bloomberg.com/news/articles/2020-04-09/coronavirus-may-reactivate-in-cured-patients-korean-cdc-says↩
2. ^[2]Kyunghee Park, “Coronavirus May ‘Reactivate’ in Cured Patients, Korean CDC Says,” Bloomberg, April 9, 2020, https://www.bloomberg.com/news/articles/2020-04-09/coronavirus-may-reactivate-in-cured-patients-korean-cdc-says↩
3. ^[3]Kyunghee Park, “Coronavirus May ‘Reactivate’ in Cured Patients, Korean CDC Says,” Bloomberg, April 9, 2020, https://www.bloomberg.com/news/articles/2020-04-09/coronavirus-may-reactivate-in-cured-patients-korean-cdc-says↩
4. ^[4]Christopher Weaver, “Questions About Accuracy of Coronavirus Tests Sow Worry,” Wall Street Journal, April 2, 2020, https://www.wsj.com/articles/questions-about-accuracy-of-coronavirus-tests-sow-worry-11585836001↩
5. ^[5]Kyunghee Park, “Coronavirus May ‘Reactivate’ in Cured Patients, Korean CDC Says,” Bloomberg, April 9, 2020, https://www.bloomberg.com/news/articles/2020-04-09/coronavirus-may-reactivate-in-cured-patients-korean-cdc-says↩