Millions of people may have had coronavirus in the past without knowing it – American CDC

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 one-day 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 all-time 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.

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 said.

“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 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.

Some cases went unnoticed partly because testing was at first limited to people who were very ill, Redfield said. As more people get tested, he added, it’s clear a large percentage had mild symptoms or none at all.

States postpone reopening plans

Coronavirus has killed more than 124,000 people in the United States, and confirmed cases are surging in a majority of the country.

So far, 32 states are reporting an increase in new coronavirus cases this week as compared to the prior week. Eleven of them report a 50% increase or greater. They include Montana, Idaho, Vermont, Nevada, Arizona, Texas, Florida, Georgia, Michigan, Missouri and Mississippi.

“It’s growing, and it’s growing fast across all age groups and demographics,” Arizona Gov. Doug Ducey said at a news conference Thursday. “Anyone can get this virus, and anyone can spread this virus.”

Arizona health officials reported new cases topping 3,000 as of last week, a pace that could soon overwhelm hospital intensive care facilities, the governor said. “We expect that our numbers will be worse next week and the week following,” Ducey said.

In Texas, Gov. Greg Abbott paused any further phases to reopen as the state recorded nearly 6,000 Covid-19 cases Thursday.

Abbott’s moves came as his state, California and Florida — the three-most populous — set records for new coronavirus cases.

Florida Gov. Ron DeSantis also indicated his state would not be moving to relax present restrictions. So did Gov. Michelle Lujan Grisham of New Mexico, who said the state is putting further economic reopening plans on hold.

California Gov. Gavin Newsom declared a budget emergency to free up $16 billion to fight the pandemic. The state’s hospitals have seen a 32% increase in patients with coronavirus over the past two weeks, he said.

The list of most vulnerable is updated

At the beginning of the pandemic, health experts didn’t focus on younger people because the priority was the older population and those with underlying health conditions.

With the rising numbers, some states are warning that the virus is affecting a wider range of people. More younger people testing positive is a “smoldering fire” that will hit vulnerable populations, said Erin Bromage, a biology professor at the University of Massachusetts Dartmouth.

Meanwhile, federal health officials updated the list of who’s most at risk of severe complications from Covid-19.

So are those with conditions such as sickle cell disease, poorly controlled HIV infection, bone marrow transplants or an organ transplant.

The CDC also removed the specific age threshold, saying it’s not just those over age 65 who are at increased risk for severe illness.