At Least 97,000 Children in the U.S. Tested Positive in Last 2 Weeks of July

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At least 97,000 children in the U.S. tested positive for the coronavirus in the last two weeks of July.

At least 97,000 children in the United States tested positive for the coronavirus the last two weeks of July alone, according to a new report from the American Academy of Pediatrics and the Children’s Hospital Association. The report says that at least 338,000 children have tested positive since the pandemic began, meaning more than a quarter have tested positive in just those two weeks.

The report comes as parents and education leaders grapple with the challenges of resuming schooling as the virus continues to surge in parts of the country.

More than seven out of 10 infections were from states in the South and West, according to the report, which relied on data from 49 states along with Washington, D.C., Puerto Rico and Guam. The count could be higher because the report did not include complete data from Texas and information from parts of New York State outside of New York City.

Missouri, Oklahoma, Alaska, Nevada, Idaho and Montana were among the states with the highest percent increase of child infections during that period, according to the report.

New York City, New Jersey and other states in the Northeast, where the virus peaked in March and April, had the lowest percent increase of child infections, according to the report.

In total, 338,982 children have been infected, according to the report.

Not every locality where data was collected categorized children in the same age range. Most places cited in the report considered children to be people no older than 17 or 19. In Alabama, though, the age limit was 24; in Florida and Utah the age limit was 14.

The report noted that children rarely get severely sick from Covid-19, but another report, from the Centers for Disease Control and Prevention, highlighted how the threat from a new Covid-19-related condition, called Multisystem Inflammatory Syndrome in Children or MIS-C, has disproportionately affected people of color.

The C.D.C. said that from early March through late July, it received reports of 570 young people — ranging from infants to age 20 — who met the definition of MIS-C. Most of those patients were previously healthy, the report said.

About 40 percent were Hispanic or Latino; 33 percent were Black and 13 percent were white, the report said. Ten died and nearly two-thirds were admitted to intensive care units, it said. Symptoms include a fever, rash, pinkeye, stomach distress, confusion, bluish lips, muscle weakness, racing heart rate and cardiac shock.

The Georgia high school whose crowded hallways flooded social media has nine new coronavirus cases.

A reopened high school in Georgia that drew national attention over images of its crowded hallways has had at least nine coronavirus cases reported in the last week, and is switching to online-only instruction for at least the next two days while the school is disinfected and officials assess the situation.

“At this time, we know there were six students and three staff members who were in school for at least some time last week who have since reported to us that they have tested positive,” Gabe Carmona, the principal of North Paulding High School in Dallas, Ga., said in a letter to parents and guardians of the school’s students on Saturday.

The superintendent of the Paulding County School District, Brian Otott, sent them another letter Sunday advising them about the switch to online instruction for Monday and Tuesday, at the least.

Both letters encouraged parents to check their children’s temperature twice daily and to monitor them for symptoms. Neither letter made any mention of social distancing or wearing masks, which the school has said are encouraged but not mandatory.

Photos circulated widely online last week showed North Paulding students crowded in a school hallway with few in masks. Hannah Watters, a 15-year-old student who posted one of the images, was initially suspended for doing so but the suspension was rescinded.

After the photo spread over social media, Mr. Otott said masks were not required at the school, which has about 2,000 students, because “there is no practical way to enforce a mandate to wear them.”

But Dr. Gary Voccio, the health director for Paulding County and nine other counties in Northwest Georgia, said that masks were crucial to containing the spread of the virus.

“Of course you have to change classrooms, and it’s going to be very difficult to physically distance when that occurs,” Dr. Voccio said in a video posted on Facebook. “But the masks, again, are the important part of this problem. And we will have significant cases within the schools, I’m sure.”

At least 66 new coronavirus deaths and 4,032 new cases were reported in Georgia on Saturday, according to a New York Times database.

Use rapid tests, but use them carefully, Ohio’s governor says after a false-positive scare.

Governor DeWine got the positive result when he was screened before President Trump arrived in Ohio for campaign appearances.

That test was an antigen test manufactured by the diagnostic health care company Quidel, one of two such tests given emergency use authorization by the Food and Drug Administration. These tests, while fast and convenient, are known to be less accurate than PCR tests, which were used to retest Governor DeWine twice on Thursday and once more on Saturday. All three PCR tests came back negative, confirming that the governor is not infected.

His experience could raise concerns about how much states will rely on antigen tests to augment other forms of testing that are in short supply. Ohio is one of seven states that said this week that they were banding together to purchase a total of 3.5 million rapid coronavirus tests, including antigen tests, along with other vital supplies. Governor DeWine said on CNN Sunday that he had already been in touch with Gov. Larry Hogan of Maryland to talk about the tests and the seven-state agreement.

“If anyone needed a wake-up call with antigens, how careful you have to be, we certainly saw that with my test,” Governor DeWine said. “And we’re going to be very careful in how we use it.”

He added that he would direct any funding from a new federal relief package to expanded testing and helping schools adapt.

“We have doubled our testing in the last four weeks,” he said. “We need to double it again and then double it again. And so that is not going to be cheap to do.”

PCR tests are in short supply nationwide, and turnaround times for results have stretched past two weeks in some parts of the country, rendering the information useless.

Compared with PCR tests, Quidel’s antigen test is more likely to return a false negative result, missing up to 20 percent of cases that PCR detects, though the figure may drop below 5 percent for patients with high virus levels. But Governor DeWine’s antigen test produced the opposite error: a false positive.

He noted on Sunday that antigen tests function especially well as screening tests, delivering a quick preliminary indication that can be confirmed by the more accurate but slower PCR tests.

Virus cases have surged in the United States in recent weeks, particularly in the Sun Belt states and in communities where officials moved quickly to reopen. According to a New York Times database, the United States leads the world in confirmed cases with more than five million — a milestone reached on Saturday — followed by Brazil and India. Experts have warned that the actual number of people infected is far greater than the confirmed case count. Brazil also reached a milestone of 100,000 deaths on Saturday.

Trump’s moves on economic aid draw fire on the Sunday news shows.

Administration officials struggled in television appearances on Sunday to explain President Trump’s attempts to circumvent Congress in the absence of an agreement on a coronavirus aid package, sowing further confusion over whether tens of millions of Americans will receive the promised relief.

The president announced executive steps on Saturday that he said were intended to address lapsed unemployment benefits, reinstate an eviction ban, provide relief for student borrowers and suspend collection of payroll taxes. They came after crucial benefits provided under earlier aid bills had lapsed, and after two weeks of talks between congressional Democrats and administration officials failed to yield an agreement on a broader relief package.

But Mr. Trump’s steps appeared unlikely to have a meaningful impact on the sputtering economy, raising questions about whether Mr. Trump had taken them mainly to gain more leverage in his face-off with Congress.

Democrats criticized the actions on Sunday as executive overreach, and warned that the nation’s social safety net could be jeopardized.

“The president’s meager, weak and unconstitutional actions further demand that we have an agreement,” Speaker Nancy Pelosi of California said on “Fox News Sunday.”

She, along with Senator Chuck Schumer of New York, the minority leader, urged administration officials to resume talks and seek a compromise on a broad relief package.

“The president’s executive orders, described in one word, could be paltry; in three words, unworkable, weak and far too narrow,” Mr. Schumer said on the ABC program “This Week.”

Mr. Trump’s top economic advisers were on the defensive Sunday about whether the president had the authority to bypass Congress, which retains the constitutional power of the purse, and redirect billions of dollars in spending. But there was some acknowledgment that the measures were not as potent as congressional action would be.

“The downside of executive orders is, you can’t address some of the small business incidents that are there,” said Mark Meadows, the White House chief of staff, in a prerecorded interview that was broadcast Sunday on Gray Television. “You can’t necessarily get direct payments, because it has to do with appropriations. That’s something that the president doesn’t have the ability to do. So, you miss on those two key areas. You miss on money for schools. You miss on any funding for state and local revenue needs that may be out there.”

Kansas City, a potential hot spot, needs federal aid to cope, the mayor says.

Like many communities, Kansas City, Mo., has been having a tough time lately, and it will get tougher if Congress and the White House can’t reach a deal on more aid, the city’s mayor, Quinton Lucas, said on Sunday.

Dr. Deborah Birx, the White House coronavirus coordinator, recently named Kansas City as one of 10 potential coronavirus hot spots around the country because of troubling signs in its testing data. Daily case counts have been declining, but the city is experiencing huge backlogs in testing that are delaying results by as much as two weeks, making them nearly useless in heading off the spread of the disease.

What will it take to address the problem? “Money,” Mr. Lucas said Sunday on the CBS program “Face the Nation.” “We need more resources to get more testing, to get faster testing through.”

Kansas City’s Covid-19 response has already cost the city millions, and without federal aid, a growing budget deficit may soon force officials to start furloughing workers and eliminating jobs.

“This isn’t just theoretical for us,” he said. “These are issues that are significant and in the now, and so we are looking for a deal.”

Kansas City has delayed the start of its school year until after Labor Day to buy more time to make its schools safe to reopen. But the schools need more money to buy protective equipment and implement social distancing measures, Mr. Lucas said.

He said it was difficult to make the right decisions locally without clear guidance from the federal government: “I’m a lawyer by training. I talk to doctors and health care professionals here, but these are calls necessarily that sometimes mayors may not be equipped to make, or some governors.”

Pfizer strikes a deal with Gilead, the maker of remdesivir, to manufacture the urgently needed drug.

With the number of severely ill patients rising and with remdesivir, the only drug shown to speed recovery, in short supply, an urgent need to quickly increase remdesivir production has arisen. Some U.S. hospitals have been forced to ration the drug, using various systems to decide who should get it.

Now, in a rare agreement between drug companies, Pfizer has entered into an agreement with Gilead Sciences, the maker of remdesivir, to manufacture the drug at a facility in Kansas. It is meant to be part of an effort to quickly increase the drug’s supply.

Pfizer will be one of 40 companies in North America, Europe and Asia that will be making the drug. Gilead says it plans to produce more than two million courses of treatment by the end of 2020. It says it also will produce another several million doses of remdesivir in 2021 if they are needed.

Remdesivir is an anti-viral drug that failed as a treatment for hepatitis C but was tested in Covid-19 patients because it seemed effective against the virus in laboratory studies and because its safety had already been determined. It is supplied intravenously.

The evidence of its effectiveness against the new coronavirus comes from a federal study of 1,000 hospitalized patients who received remdesivir or a placebo. Preliminary results were announced on April 27, and on May 1, the Food and Drug Administration gave the drug emergency use authorization, allowing Gilead to sell remdesivir even though it has not yet been approved. The price for a five-day course is $3,120.

Gilead explains the supply problems by saying it is difficult and time consuming to make remdesivir. The company says manufacturing is “a long, linear chemical synthesis process that must be completed sequentially and includes several specialized chemistry steps and novel substances with limited global availability.”

Your immune system may already recognize the coronavirus.

Eight months ago, the new coronavirus was unknown. But to some human immune cells, it was already something of a familiar foe.

A flurry of recent studies has revealed that a large proportion of the population — in some places, 20 to 50 percent of people — may harbor immunity assassins called T cells that recognize the new coronavirus despite having never encountered it before.

These T cells, which lurked in the bloodstreams of people long before the pandemic began, are most likely stragglers from past scuffles with other related coronaviruses, including four that frequently cause common colds. It’s a case of family resemblance: In the eyes of the immune system, germs with common roots can look alike, such that when a cousin comes to call, the body may already have an inkling of its intentions.

The presence of these T cells has intrigued experts, who say it is too soon to tell whether the cells will play a helpful, harmful or entirely negligible role against the current coronavirus.

But should these cross-reactive T cells exert even a modest influence on the body’s immune response, they might make the disease milder — and perhaps partly explain why some people who catch the germ become very sick while others are dealt only a glancing blow.

This contact tracer is fighting two contagions: the virus and fear.

Radhika Kumar goes to work every morning hoping to save lives. As a contact tracer for Los Angeles County, her job, at least on paper, entails phoning people who have tested positive for the coronavirus, along with others they may have exposed, and providing them with guidance on how to isolate so as not to infect others.

If that sounds easy, it is not.

To persuade people to cooperate, she has to get them to trust her. She has to convince them that they might be infected, even if they have no symptoms. She has to let people curse at her and hang up, then she has to call them back the next day.

And if she wants them to heed her advice, she has to listen, really listen, to how scared they are that if they stay home from their jobs, they might not be able to feed their families.

“Sometimes it can really get to you,” she said. “The other day I had one young lady, and she was screaming on the phone, ‘You don’t understand — I have three kids. I have to go to work.’”

“I kept calling back and calling back,” Ms. Kumar said. “I’m very relentless like that. I thought about it all night — what am I going to do? I called her again first thing in the morning, and I was so relieved when she picked up.”

Even as officials at the Centers for Disease Control and Prevention continue to tout the effectiveness of contact tracing, and state and local health agencies across the United States deploy new armies of tracers, tracking down everyone with the coronavirus is proving to be a Sisyphean task.

GlobAl Roundup

France will require masks in crowded outdoor areas starting on Monday.

France is imposing a new requirement that people wear face masks outdoors in crowded areas of Paris and other major cities beginning on Monday as the number of coronavirus infections rises at the fastest rate since a national quarantine ended in mid-May.

The country had gotten the number of infections under control, but the pandemic is creeping back, with 2,288 new Covid-19 cases reported on Friday — the third consecutive day of sharp increase. In the Paris Ile-de-France region, the rate of infections reached 2.4 percent on Friday, compared with a 1.6 percent national average.

The rise of new clusters has led the government to warn of the possibility of a second wave of infections in the autumn. In an effort to stem the spread of the virus, masks will now be mandatory for people age 11 and above in high-traffic areas, from the tourist havens of Saint Tropez and Biarritz to the Seine river in Paris, Montmartre and other popular sites, as well as at outdoor food markets and in Paris’s crowded suburbs.

The police will be enforcing the measures — which will be in place for at least a month in Paris and are subject to review in other areas — with a fine of 135 euros ($159).

The authorities are especially concerned about the popularity of “free parties,” in which hundreds of young people gather in the Parisien woods and other areas, often without wearing masks.

Wearing a mask in crowded enclosed spaces, including museums, shopping malls and on public transportation, has been compulsory in France since mid-July.

Here is what else is happening around the world:

• At least nine people were killed after a fire broke out on Sunday at a hotel in southern India that was being used as a makeshift facility for Covid-19 patients, officials said. The police attributed the accident to a short circuit in an air-conditioner on the ground floor of the Swarna Palace.

• New Zealand on Sunday marked 100 days without any new reported cases of local transmission of the coronavirus, a milestone as the pandemic continues to devastate countries across the world. New Zealand, a nation of five million people, reported in March that it had stamped out the virus after strict lockdown measures were implemented. Dr. Ashley Bloomfield, the country’s top health official, said it was “a significant milestone” but added “we can’t afford to be complacent.”

BUSINESS ROUNDUP

A biotech company says it’s making inroads with a vaccine. Experts are skeptical.

In 2009, when H1N1, better known as swine flu, was stoking fears of a devastating pandemic, a small biotech company named Inovio Pharmaceuticals rushed to create a vaccine. After announcing promising early results, the company’s stock soared more than 1,000 percent.

In the years since, Inovio has announced encouraging news about its work on vaccines for malaria, the Zika virus and even a “cancer vaccine.” The declarations have caused the company’s stock price to leap, enriching investors and senior executives.

There is a catch, though: Inovio has never brought a vaccine to market.

Now, Inovio is working on a vaccine for the coronavirus, and a flurry of positive news releases about its funding and preliminary results have helped the company attract money from the U.S. government and investors.

But some scientists and financial analysts question the viability of Inovio’s technology. While there are some early signs of promise with its vaccine, Inovio has released only bare-bones data from the first phase of clinical trials. It is locked in a legal battle with a key manufacturing partner that claims Inovio stole its technology.

And while the company has said that it is part of Operation Warp Speed — the flagship federal effort to quickly produce treatments and vaccines for the coronavirus — Inovio is not on the list of companies selected to receive financial support to mass-produce vaccines.

“The absence of that funding, coupled with their ongoing litigation, coupled with the need to scale a device, coupled with the absence of complete Phase 1 data, makes people skeptical,” said Stephen Willey, an analyst at Stifel, an investment firm.

Inovio could provide an update on its progress with the vaccine when it releases its second-quarter financial results on Monday.

In other business news:

• Saudi Aramco, the world’s largest oil company, said on Sunday that its quarterly earnings had plunged more than 73 percent compared with a year ago, as lockdowns imposed to curb the pandemic drastically cut the demand for oil. Despite the steep fall in earnings, to $6.6 billion from $24.7 billion, the company said it would continue paying a quarterly dividend of $18.75 billion — nearly all of which will go to the Saudi government.

Meet the people at the big biker rally, undaunted by the virus.

Despite the coronavirus pandemic, tens of thousands of motorcycle enthusiasts converged over the weekend outside the small South Dakota community of Sturgis for the 80th annual Sturgis Motorcycle Rally. Officials said about 250,000 enthusiasts were expected this year — about half the number who attended last year, but a figure that would still make the rally one of the country’s largest public gatherings since the first coronavirus cases emerged in the spring.

Many in attendance said they were not concerned about the virus as they walked around without masks.

A New Hampshire poet laureate brightens up her city’s Covid-19 advisories.

On Sundays, thousands of residents of Portsmouth, N.H., find a poem nestled inside the city’s Covid-19 newsletter.

The poems, written by Tammi J. Truax, the city’s poet laureate, help offset the gloom of the pandemic while giving residents a chance to pause briefly and reflect on something other than the coronavirus.

Since the beginning of the pandemic, there have been more than 6,800 cases and at least 419 deaths in New Hampshire, according to a New York Times database, with a recent average of 28 cases per day.

The idea for featuring the poems came from Stephanie Seacord, the public information officer in Portsmouth, a city of about 21,000 residents about 60 miles north of Boston. Ms. Seacord was compiling information about the virus and health updates in a weekly city newsletter sent to about 5,000 email subscribers and circulated on social media.

“When the pandemic hit, it became quickly clear that people needed information more than once a week,” Ms. Seacord recalled in an interview last week, adding that “things were changing almost on a daily basis.”

In mid-March, the newsletter turned into a daily advisory of coronavirus cases and tips, like where to find personal protective equipment. Around that time, Ms. Seacord had the idea that including a poem in the Sunday newsletter would be “a good calm moment in the middle of the intensity,” she said.

Wondering about mass transit?

If you are feeling ready to go somewhere slightly out of the way, you may be worried about the buses, trains or planes you need to get there. Here’s some information to help ease your anxiety and remain safe on mass transit.

Reporting was contributed by Liz Alderman, Emily Cochrane, Johnny Diaz, David Gelles, Rebecca Halleck, Gina Kolata, Giulia McDonnell Nieto del Rio, Heather Murphy, Azi Paybarah, Alan Rappeport, Stanley Reed, Ben Shpigel, Derrick Taylor, Lucy Tompkins, Mark Walker, Katherine J. Wu and Ceylan Yeginsu.