As states reopen and more tests are conducted, coronavirus cases continue to ravage the U.S. The Post spoke with experts to determine what wave we’re in. (Video: The Washington Post, Photo: Sarah Hashemi/The Washington Post)

With novel coronavirus infections setting a single-day national record Wednesday, health experts are taking little solace from one of the few bright spots in the current resurgence: Deaths are not rising in lockstep with caseloads.

But that may be just a matter of time.

“Deaths always lag considerably behind cases,” Anthony S. Fauci, the nation’s top infectious-disease specialist, told Congress at a hearing Tuesday. In the weeks to come, he and others said, the death toll is likely to rise commensurately.

Which means Arizona, Texas and Florida, states that reopened early and now are experiencing runaway infection rates, are likely to be burying more dead in July.

Florida has become a coronavirus hot spot. Covid-19 cases have been on the rise since the state reopened in early May, surpassing 100,000 on June 22. (Video: Robert Ray/The Washington Post)

“As long as there is a fair amount of testing going on, if there is an uptick in covid-19 infections, then we are likely to see that in the confirmed case data before we see it in the death data,” said Nicholas G. Reich, associate professor of biostatistics at the University of Massachusetts at Amherst, in an email.

He predicted “rises in covid-19 deaths over the next month in many of the states that are seeing upticks in cases, like Texas, California, Florida and others, even though the deaths have been either steady or declining in recent weeks.”

The virus has come surging back in recent days, with 38,173 U.S. infections Wednesday, more than any previous day in the pandemic, including the catastrophic days of April. This time, the increases are mainly in the South and West, while New York and New Jersey, which were nearly overwhelmed in the spring and have been slow to reopen, are seeing declining cases.

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California, which shut down early and has taken a slow approach toward reopening, nevertheless reported more than 7,000 new cases Wednesday, easily surpassing its record of 5,019 set Tuesday. Oklahoma — where President Trump on Saturday held an indoor campaign rally — and Florida also hit new single-day highs Wednesday.

Those three states, along with Nevada and North Carolina, reached new peaks in their seven-day rolling averages, considered a more reliable indicator of the virus’s impact. Arizona set a record with 2,270 hospitalizations.

Coronavirus hospitalizations have tripled in Houston since Memorial Day, Houston Methodist Hospital chief executive Marc Boom said Wednesday. Texas reported 5,551 new cases, the most in a single day, along with 4,389 hospitalizations, up almost 300 from Tuesday’s record high.

The state’s seven-day rolling average of new cases has increased 70 percent since last Tuesday, setting a record for the 14th consecutive day.

Overall, 2.36 million people have been infected in the United States and at least 119,000 have died — by far the largest numbers for any country in the world.

Governors of New York, New Jersey and Connecticut said they will advise travelers arriving from states with wide community spread of the virus to quarantine for 14 days, the three announced Wednesday at a joint news conference.

The new rules will apply to people from states with an infection rate of 10 per 100,000 people on a seven-day rolling average, or a 10 percent or greater positive test rate over a seven-day period, according to New York Gov. Andrew M. Cuomo (D). Eight states currently are in that group: Alabama, Arkansas, Arizona, Florida, North Carolina, South Carolina, , Utah and Texas. On Wednesday, the state of Washington was erroneously included but has since been removed from the restriction.

Despite the numbers, Vice President Pence urged Republican senators during a closed-door lunch to focus on “encouraging signs.” Lawmakers have begun to express alarm about rising infection rates in states such as Florida, Arizona and Texas, which are likely to be critical in the outcome of the presidential race and control of the Senate.

Senators said Pence pointed to positive indicators, including the lagging mortality rate. That is partly because there is more testing, and younger and healthier people now account for larger shares of those getting tested, Pence contended.

Stocks, meanwhile, fell on news of the increase in cases, as the International Monetary Fund said Wednesday that the global economy will shrink by 4.9 percent this year and a sluggish recovery would follow.

Officials tracking the startling comeback of covid-19, the disease caused by the virus, are somewhat buoyed by lessons learned and progress in the health-care system since the virus stormed ashore outside Seattle in late February and later inundated New York City.

Some said the greater availability of tests is responsible for turning up more cases. The results of those tests are revealing a larger number of younger people with the virus than there were in the early days of the outbreak.

When the pandemic first gripped the United States, it was nearly impossible for anyone without severe symptoms to secure a test. Younger people, who generally suffer milder cases and are more likely to be asymptomatic, may have been underrepresented as a result, said Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health’s Center for Health Security.

Now they are accounting for some of the rise in the overall caseload and a greater proportion of hospitalizations in places like Arizona. There may be fewer deaths among the younger group, but those individuals are likely to infect more older people, she said.

With states reopening, “you have the young folks out and about. They’re spreading it,” she said. “It may take time to find its way to older, vulnerable people, who are more likely to die.”

Tom Frieden, former director of the Centers for Disease Control and Prevention, said older people now have a better understanding of how vulnerable they are. The medical system also has taken steps to better protect people older than 65, including those living in nursing homes and other care facilities. The virus is no longer racing through those places and killing people by the ­dozens, as it did early in the pandemic.

CDC statistics show how thoroughly covid-19 attacks the elderly. From Feb. 1 to June 13, covid-19 was involved in just 2,630 deaths among people 44 or younger. But the disease was fatal to 83,426 people 65 or older.

Medical care for the most critically ill patients also has improved during the four months that U.S. caregivers have been battling the disease. Doctors have become more adept at using ventilators and othertools and techniques to help patients breathe. They have turned to drugs like remdesivir and dexamethasone. , which has shown a small benefit for seriously ill patients, and the steroid dexamethasone, which has reduced the risk of death for people with severe lung damage. Sick people have learned to track the level of oxygen in their blood with home use of pulse oximeters.

Even if the death toll does not rebound to previous levels, the current surge will have serious consequences, said Saskia Popescu, an infectious-disease epidemiologist who teaches at the University of Arizona. For some people who do not become critically ill, the virus can cause severe, and sometimes long-lasting, problems, she said.

“Illness is a really significant outcome too,” Popescu said. “Deaths are obviously worst case; we don’t want people to die. But I don’t want people to get sick, especially so sick they have to go the hospital. That’s hard on them, that’s hard on the health-care system. Focusing only on deaths does a disservice to patients and the community.”

Jacqueline Dupree and Erica Werner contributed to this report.

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