(HealthDay)—As U.S. coronavirus infections surged in many states, four of America's top health officials plan to testify in Congress on Tuesday about how to safely reopen the country.

Originally billed as an "update on progress toward safely getting back to work and back to school," members of the Senate's health and education committee will instead have to tackle the reality that reopening hasn't proven safe or easy, The New York Times reported.

Dr. Anthony Fauci will be joined at the hearing by Dr. Robert Redfield, director of the U.S. Centers for Disease Control and Prevention; Food and Drug Administration Commissioner Dr. Stephen Hahn; and Adm. Brett Giroir, the assistant secretary for health.

With new cases spiking in many parts of the country, at least a dozen states and cities have slowed reopening plans, the Washington Post reported.

Not only case counts are climbing: COVID-19 hospitalizations are spiking in seven states, the Post reported. In Texas, Arizona, Nevada, South Carolina, Montana, Georgia and California, seven-day averages are up at least 25 percent from last week, the newspaper said.

In California, case counts have exploded, now surpassing 220,000 infections, the Times reported. Gov. Gavin Newsom has been forced to roll back the state's reopening in some counties. On Monday, he said the number of people hospitalized in California had increased 43 percent over the past two weeks. More than 7,000 new cases were announced across California on Monday, the highest single-day total of the pandemic, the newspaper reported.

California was the first state to go into lockdown, but state officials who were so proactive in curbing the spread of COVID-19 now have to ask themselves what went wrong.

"To some extent, I think our luck may have run out," Dr. Bob Wachter, chair of the department of medicine at the University of California, San Francisco, told the Times. "This is faster and worse than I expected."

Public health experts have also cautioned that Florida could become the next epicenter for infections while Texas has seen record-breaking case counts and hospitalizations, CNN reported. Officials across the country are also warning of an increase in cases among younger people.

Over the weekend, Florida shattered its previous records and reported 9,585 new cases on Saturday and 8,530 on Sunday, the Times reported. Orange County, home to Orlando, has seen an explosion of coronavirus: nearly 60 percent of all cases there have come in the past two weeks.

The city of Jacksonville, which plans to host the Republican National Convention in August, announced Monday that face masks would be mandatory in any indoor spaces where social distancing isn't possible. Florida Gov. Ron DeSantis has blamed the state's increase on a "test dump," largely from younger residents getting themselves tested for COVID-19.

Rising cases in South alarm federal health officials

Coronavirus response task coordinator Dr. Deborah Birx said last week that rising positive test rates in states across the South, including Texas, Arizona, Florida and Mississippi, were causing significant concern among health officials, and that they had created an "alert system" to track them.

She used Texas as an example where higher positive test rates suggest a kind of spread that could not be explained completely by higher rates of testing. Texas is part of a group of states with positive test rates above 10 percent, a threshold the White House has used to identify areas of particular concern, she explained.

Texas Gov. Greg Abbott, speaking in Dallas on Sunday, said that the virus had taken a "very swift and a very dangerous turn" in his state, the Times reported. The increase in the rate of positive coronavirus tests, to over 13 percent in the past month from less than 4 percent, is an "alarm bell," he warned.

Coronavirus-related hospitalizations are also surging in that state, reaching a record high for the 16th day in a row on Saturday, the Washington Post reported.

A handful of states have actually brought the virus under control after being slammed in the early stages of the pandemic. Determined to keep case counts low, New York, Connecticut and New Jersey have said they will now mandate quarantines for travelers coming from states that are experiencing large spikes in new cases, the Times said.

On Sunday, New York Gov. Andrew Cuomo announced that only five coronavirus-related deaths had been reported over the previous 24 hours, the lowest single-day death toll in the state since March 15. The number of COVID-19 patients being hospitalized also dropped below 900 for the first time since March, the Post reported. In a statement, Cuomo noted the numbers would "shoot right back up" if people failed to follow social distancing protocols.

By Tuesday, the U.S. coronavirus case count passed 2.6 million as the death toll passed 126,000, according to a Times tally.

According to the same tally, the top five states in coronavirus cases as of Tuesday were: New York with over 397,600; California with nearly 224,000; New Jersey with more than 173,000; Texas with over 158,700 and Florida with over 146,000.

Vaccines and treatments

There has been some good news in recent weeks, however. Researchers at Oxford University in England announced that dexamethasone, a widely used, low-cost steroid, appears to cut the death rate for ventilated COVID-19 patients by one-third. It also lowered the death rate for patients who require oxygen (but are not yet on a ventilator) by one-fifth, the Times reported.

"Bottom line is, good news," Fauci, who directs the U.S. National Institute of Allergy and Infectious Diseases, told the Associated Press. "This is a significant improvement in the available therapeutic options that we have."

But at least three manufacturers of the drug have reported shortages, according to the American Society of Health-System Pharmacists, STAT News reported. Two of the manufacturers cited increased demand as a reason for their shortages.

Meanwhile, the search for an effective vaccine continues. The U.S. Department of Health and Human Services (HHS) has said that it would provide up to $1.2 billion to the drug company AstraZeneca to develop a potential coronavirus vaccine from Oxford University, in England.

The fourth, and largest, vaccine research agreement funds a clinical trial of the potential vaccine in the United States this summer with about 30,000 volunteers, the Times reported.

The goal? To make at least 300 million doses that could be available as early as October, the HHS said in a statement.

The United States has already agreed to provide up to $483 million to the biotech company Moderna and $500 million to Johnson & Johnson for their vaccine efforts. It is also providing $30 million to a virus vaccine effort led by the French company Sanofi, the Times reported. Moderna said a large clinical trial of its vaccine candidate could begin in July.

Nations grapple with pandemic

Elsewhere in the world, the situation remains challenging.

Even as the pandemic is easing in Europe and some parts of Asia, it is worsening in India. Officials in New Delhi plan to test all of the city's 29 million residents in the next week or so, as the number of coronavirus cases neared 567,000 on Monday and pushed many hospitals to their breaking point, the Times reported.

Brazil has also become a hotspot in the coronavirus pandemic, with nearly 1.4 million confirmed infections by Tuesday, according to the Hopkins tally. U.S. President Donald Trump has issued a ban on all foreign travelers from Brazil because of the burgeoning number of COVID-19 cases in that country, CNN reported.

Cases are also spiking wildly in Russia: As of Tuesday, that country reported the world's third-highest number of COVID-19 cases, at more than 640,200, the Hopkins tally showed.

Worldwide, the number of reported infections passed 10.3 million on Tuesday, with over 505,000 deaths, according to the Hopkins tally.

More information: The U.S. Centers for Disease Control and Prevention has more on the new coronavirus.