Accuracy of U.S. coronavirus data thrown into question as decline in testing skews drop in new cases

Accuracy of U.S. coronavirus data thrown into question as decline in testing skews drop in new cases In Texas, new Covid-19 cases have fallen by 10% to an average of 7,381 a day from 8,203 two weeks ago, but testing is down by 53% over the same time. Will Feuer CNBC

For the first time in months, the daily growth of new coronavirus cases in the U.S. has steadily fallen over the past two weeks, giving some hope to U.S. officials who proclaimed there were “signs of progress” in Southern states that were hit particularly hard.

“No one’s declaring victory,” Adm. Brett Giroir, an assistant secretary at HHS, told reporters on a July 30 conference call. “We continue to see signs of progress across the Sun Belt and diffusely throughout the country.”

But testing shortages in key states and other gaps in Covid-19 data call into question the accuracy of those numbers and whether the outbreak in the U.S. is really improving or whether cases are simply going undiagnosed, epidemiologists say.

The country recorded an average of 52,875 new cases every day over the last seven days, down 19% from an average of 65,285 new cases per day on July 28, according to a CNBC analysis of data compiled by Johns Hopkins University. However, Covid-19 testing has declined as well, falling from a seven-day average of about 814,000 tests per day two weeks ago to about 716,000, a 12% decline, over the same two-week period, according to data compiled by the Covid Tracking Project, a volunteer project founded by journalists at The Atlantic magazine.

The decline in testing is particularly acute in some of the hardest-hit states with the worst outbreaks, which further skews the overall case numbers across the U.S. ...