Millions of people may have had coronavirus in the past without knowing it, CDC says

USA With infection numbers rising in more than 30 states, the US set a daily record for new coronavirus cases. And federal health officials warned that the number of people who’ve been infected is vastly undercounted.

Almost 40,000 coronavirus cases were reported Thursday, surpassing a previous oneday high on April 24, according to Johns Hopkins University. Overnight, Arizona and New Mexico joined Texas and several other states in pausing their reopening plans. Texas reported an alltime high in new cases, and Houston faces a dire critical care shortage. The developments mark a “heartbreaking situation” that demands stricter actions immediately, said Dr. Peter Hotez of Baylor College of Medicine in Houston.

“We have to save lives at this point,” he told CNN on Friday morning. Austin Mayor Steve Adler said COVID19 beds will be at capacity in the middle of July at this rate. “Pausing will not make things better,” Adler told CNN on Friday. “We need to do something that’s different than that. The status quo will not protect us.” The sudden spike in confirmed cases in recent days is no surprise, another health expert said. “Every epidemiologist was telling, screaming as loud as we could, that three weeks after Memorial Day, we’d have a peak in the cases, and five weeks after Memorial Day we’d begin to see a peak in hospitalizations and deaths,” epidemiologist Larry Brilliant told CNN on Thursday night. “If you let everybody out without face masks and without social distancing in the middle of a pandemic, this is what was predicted.” And while more than 2.4 million cases have been diagnosed nationwide since the pandemic started, the number of people who have been infected is likely to be 10 times as high. Antibody tests show more than 20 million people have been infected with coronavirus, most of them without knowing it, said Dr. Robert Redfield, director of the Centers for Disease Control and Prevention.

Antibody tests examine a person’s blood for signs that the immune system responded to an infection. Federal officials have been conducting such tests nationwide to determine how many people had past undiagnosed infections.

“A good rough estimate now is 10 to 1,” Redfield said. Between 5% and 8% of Americans have been infected with the coronavirus, with the numbers varying by region. New York, once the epicenter of the pandemic, will have a higher percentage of people with past infections than some states in the West, Redfield said. That means 90% or more have not been infected and are susceptible to the virus, highlighting the need to act aggressively to combat rising infection rates, he said.

(CNN)