Testing Did Not Reveal the Full-Scale Spread of COVID Across L.A.

Researchers found that the number of adults infected with COVID in the county was three times higher than what tests reflected between May and June of last year

The number of people who have been infected with COVID in Los Angeles County is far greater than testing previously showed, according to a new state study.

Health officials say this is due largely to people who have never developed symptoms and did not get tested, or those who couldn’t access tests, City News Service reports.

Using results of antibody tests performed on a control group, researchers found that the number of adults infected with COVID in the county was three times higher than what tests reflected between May and June of last year. Among children, the numbers were more stark, as researchers found that five times more children were actually infected than testing confirmed, City News Service reports.

“The researchers estimated that at the time of the study, which was back in late spring of 2021, 30 percent of L.A. County adults had been infected and 37 percent of children had been infected,” L.A. county Public Health Director Barbara Ferrer said of the results from the CalScope study.

During that time period, the county was only reporting infections in 10 percent of adults and slightly under 10 percent of children, Ferrer said. The differences in actual infections versus reported cases were due to the shortcomings of the testing system, she said, adding that many asymptomatic people never got tested and access to testing was limited at times, which prevented people from being able to confirm their infection.

The availability of at-home testing has also impacted the official case county since people who test at home don’t necessarily report their results to the county, Ferrer said.

The study data “can serve as an indication of the large number of infections that go unreported in L.A. County,” she said. “This is important to understand because it gives us a sense of the true scope and impact of the pandemic.”

The study arrives as the county sees a steady increase in infection rates driven by the BA.2 subvariant of the virus. It is now believed to account for 67 percent of all infections locally—a jump from 47 percent one week ago and from 32 percent the week prior, City News Service reports.

The county is now averaging more than 1,000 new COVID cases per day over the past week, compared to 878 from the week prior, Ferrer said.

But while infection rates have been increasing, the county is not seeing an uptick in hospitalizations or deaths at this time—a fact that Ferrer said could be the result of increased vaccination rates or other levels of immunity preventing people from becoming severely ill from the virus, City News Service reports.

However, Ferrer warned that a COVID infection still has the potential for severe consequences, including death.

“We’re seeing sort of the steady, small increases, somewhere between two percent to three percent rise every day in cases,” she said. “At some point this will become more concerning if it doesn’t level off, and our hope is that it does level off. Our hope is that in fact people recognize we’ve got a more infectious subvariant circulating. Be more careful. Put that mask on in these higher-risk settings. Go ahead and get tested when you’re gathering. Be sensible to try to avoid either a re-infection or a new infection.”

L.A. County reported 1,214 new infections on Thursday, bringing the overall total to 2,849,185 since the start of the pandemic, according to the county’s tracking website. An additional 12 deaths were also reported, raising the overall death toll to 31,839.

The county on Friday ended its mandate to quarantine asymptomatic people exposed to the virus. Previously, those who were exposed to an infected person had to stay home for at least five days to determine whether they would test positive or become sick, provided they remain symptom-free, the Los Angeles Times reports.

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