Doubts Rise About Accuracy of Public COVID Counts as at-home testing surges

As At-Home Tests Surge, Doubts Rise About Accuracy of Public COVID Counts Millions of rapid at-home COVID tests are flying off pharmacy shelves across the country, giving Americans an instant, if sometimes imperfect, read on whether they are infected with the coronavirus. But the results are rarely reported to public health departments, exacerbating the long-standing challenges of maintaining an accurate count of cases at a time when the number of infections is surging because of the omicron variant. At the minimum, the widespread availability of at-home tests is wrea YahooNews

Millions of rapid at-home COVID tests are flying off pharmacy shelves across the country, giving Americans an instant, if sometimes imperfect, read on whether they are infected with the coronavirus.

But the results are rarely reported to public health departments, exacerbating the long-standing challenges of maintaining an accurate count of cases at a time when the number of infections is surging because of the omicron variant.

At the minimum, the widespread availability of at-home tests is wreaking havoc with the accuracy of official positivity rates and case counts. At the other extreme, it is one factor making some public health experts raise a question that once would have been unthinkable: Do counts of coronavirus cases serve a useful purpose, and if not, should they be continued?

Our entire approach to the pandemic has been case-based surveillance: We have to count every case, and that’s just not accurate anymore,” said Dr. Marcus Plescia, chief medical officer at the Association of State and Territorial Health Officials, a national nonprofit organization representing public health agencies in the United States. “It’s just becoming a time where we’ve got to think about doing things differently.”

There is no comprehensive data on how many rapid tests are used every day, but experts say it is most likely far higher than the number of polymerase chain reaction, or PCR, tests, which are completed in a lab. PCR tests require more time to deliver results, which are reported publicly as aggregate totals.

At least one at-home test company has implemented a system to report results directly to health authorities. And some local health departments have set up systems for people to report results from rapid at-home tests. But with such a voluntary system, it is possible that millions of tests per day are going unreported, estimates Mara Aspinall, an expert in biomedical diagnostics at Arizona State University who is also on the board of directors of OraSure, a maker of rapid COVID tests.

“We certainly don’t want to discourage testing; but at the same time, we can’t leave public health authorities blind,” Aspinall said. “They rely on this information to take proactive and reactive precautions. It’s a very fine balance.”

The quick rise of at-home testing could be a tipping point in a conversation that began for public health experts months ago. At issue is the feasibility of shifting to less frequent case reporting or a “sentinel surveillance” system like the one that public health officials use to track other diseases such as the flu, which relies on a network of health care centers that track instances of the virus. Overall case numbers are extrapolated based on those case numbers.

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