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The University of South Carolina reports that more than 1,000 students currently have the virus.
The University of South Carolina has reported more than 1,000 students who have tested positive for the virus and are currently active cases. The figures, made available on the university’s Covid-19 dashboard, include a nearly 28 percent positive test rate for students between Aug. 28 and 31.
The campus community, according to the dashboard, “is strongly encouraged to increase behaviors related to physical distancing, face coverings, hand washing and reducing unnecessary social interaction. The university will increase testing, contact tracing, environmental monitoring and facility cleaning.”
The university, which has about 35,000 students, took action earlier this week against more than a dozen of them as well as several Greek life organizations that administrators said recently hosted parties or large gatherings.
The university announced that 15 students had been placed under interim suspension and that six Greek houses had been charged with student conduct violations stemming from the parties, which officials said violated emergency orders in Columbia, S.C.
The action came as nearly half of the fraternity and sorority chapter houses in the university’s Greek Village — nine of 20 — were placed under a 14-day quarantine after some students in them tested positive, administrators said.
Hundreds of students were also photographed carousing without masks at a crowded pool party on Saturday near the university, in an event that the Columbia Fire Department broke up, the newspaper The State reported.
“It was almost like Mardi Gras,” Aubrey D. Jenkins, the city’s fire chief, told the newspaper.
The C.D.C. tells health officials to be ready to distribute a vaccine by November, raising concerns over politicized timing.
The Centers for Disease Control and Prevention has notified public health officials in all 50 states and five large cities to prepare to distribute a coronavirus vaccine to health care workers and other high-risk groups as soon as late October or early November.
The new C.D.C. guidance is the latest sign of an accelerating race for a vaccine against a disease that has killed more than 184,000 Americans. The documents were sent out last week, the same day that President Trump said in his speech to the Republican National Convention that a vaccine might arrive before the end of the year.
Over the past week, both Dr. Anthony S. Fauci, the country’s top infectious disease expert, and Dr. Stephen Hahn, who heads the Food and Drug Administration, have said in interviews with news organizations that a vaccine could be available for certain groups before clinical trials have been completed, if the data were overwhelmingly positive.
Public health experts agree that agencies at all levels of government should urgently prepare for what will eventually be a vast, complex effort to vaccinate hundreds of millions of Americans. But the possibility of a rollout in late October or early November has also heightened concerns that the Trump administration is seeking to rush the distribution of a vaccine — or simply to suggest that one is possible — before Election Day on Nov. 3.
“This timeline of the initial deployment at the end of October is deeply worrisome for the politicization of public health and the potential safety ramifications,” said Saskia Popescu, an infection prevention epidemiologist in Arizona. “It’s hard not to see this as a push for a pre-election vaccine.”
Three documents were sent to public health officials in all states and territories as well as New York, Chicago, Philadelphia, Houston and San Antonio on Aug. 27. They outlined detailed scenarios for distributing two unnamed vaccine candidates — each requiring two doses a few weeks apart — at hospitals, mobile clinics and other facilities offering easy access to the first targeted recipients.
The guidance noted that health care professionals, including long-term-care employees, would be among the first to receive the product, along with other essential workers and national security employees.
People age 65 or older, as well as those from “racial and ethnic minority populations,” Native Americans and incarcerated individuals — all communities known to be at greater risk of contracting the virus and experiencing severe disease — were also prioritized in the documents.
The National Academies of Sciences, Engineering and Medicine unveiled a 114-page plan on Wednesday, sponsored by the C.D.C. and the National Institutes of Health, that proposed a complicated four-phase system for priority.
The C.D.C. said in its guidance that “limited Covid-19 vaccine doses may be available by early November 2020.” It also said its plans were still hypothetical, noting, “The Covid-19 vaccine landscape is evolving and uncertain, and these scenarios may evolve as more information is available.” A C.D.C. spokeswoman confirmed that the documents were sent but declined to comment further.
A coalition of students and faculty members at the University of Iowa in Iowa City called in sick from classes on Wednesday to protest the university’s decision to continue with in-person instruction despite a sharp rise in Covid-19 cases in the past week.
The “sickout” did not appear to cause any significant disruptions, but it reflected the broad unease on campus: More than 800 people, including some faculty members, signed an online document calling on the university to move completely to online teaching.
The opposition to in-person classes comes as Iowa reported the most new cases per capita of any state in the nation over the past seven days and as Iowa State University, the in-state rival of the University of Iowa, reversed its decision to allow fans to attend its football opener on Sept. 12.
In a statement, the organizers of the sickout said that while the university was giving students the option of taking classes remotely, faculty and staff members had been pressured to return to work under threat of losing unemployment benefits.
“Many adjunct faculty are required to teach in person in classrooms that often break C.D.C. guidelines,” the statement said. “Students on scholarships that require continuous enrollment are forced to make an impossible choice: their education or their health.”
In a message sent to the faculty on Tuesday, Kevin Kregel, the university’s interim executive vice president and provost, condemned the protest, saying its members “have an obligation to deliver instruction as assigned, and to provide appropriate notice of absences due to illness.”
The university said it has taken several safety precautions for in-person instruction, including making face coverings mandatory, decreasing student density and evaluating ventilation systems. Employees at increased risk for Covid-19 are able to request alternative work arrangements.
At Iowa State University in Ames, the administration had been facing scrutiny for forging ahead with plans to host 25,000 fans at its 61,500-seat stadium for the football opener.
On Wednesday, administrators pivoted, leaving open the possibility that the seats would eventually be filled again.
“Although it is disappointing there won’t be fans at the opener, our institution’s leadership team is still committed to having spectators at future games, if it can done safely,” Jamie Pollard, the university’s athletic director, said in a statement.
Elsewhere at colleges and universities:
The University of Illinois ordered students to limit in-person activities for the next two weeks, including small gatherings, after more than 700 students tested positive for the virus since Aug. 24. The university said that students should leave their rooms only to go to class, buy groceries or food, go to work, exercise alone or attend religious services. It attributed the rise in cases to parties and students ignoring quarantine orders, saying that it would crack down on violators.
San Diego State University announced that it was suspending all in-person classes for the next four weeks and all athletic activities for two weeks after a rise in cases. Many courses had already been moved online, with lab classes being an exception.
Jamie Newman, who had been projected as the starting quarterback for the University of Georgia, one of the highest-ranked teams in the nation, tweeted that he was opting out of the college football season because of the uncertainty created by the pandemic and would prepare for next year’s National Football League draft.
Thailand reaches 100 days without any local cases.
Thailand has gone 100 days without a reported case of local transmission of the coronavirus, one of the few major nations to reach that threshold since the pandemic began.
But its success in halting the spread of the virus has come at a significant financial cost to the country, which has banned the arrival of foreign tourists, who are normally a major contributor to the economy.
The prime minister, Prayuth Chan-ocha, on Wednesday called reaching the 100-day mark a “good accomplishment” and called for continued cooperation to keep the country safe.
“If we don’t help each other, none of us can move forward and the country can’t move forward, and the people will suffer more than they already have,” he said.
Thailand’s last reported case of community transmission was confirmed on May 24. Hundreds of cases have been found since then among residents returning from abroad, but all were detected in quarantine. All returning residents are required to undergo quarantine for 14 days.
As of Thursday, Thailand had reported 3,425 cases and 58 deaths, according to a New York Times database.
Taiwan, one of the most successful places in containing the virus, has gone more than 140 days without a case of local transmission, with the last case recorded on April 8.
But other places have had difficulty going much beyond the 100-day mark.
New Zealand celebrated reaching 100 days last month only to discover a new local outbreak two days later that prompted officials to lock down the city of Auckland.
Just as Vietnam was about to reach 100 days in July, the disease broke out in the coastal city of Danang and quickly spread throughout the country. That second wave has claimed 34 lives, Vietnam’s first deaths from the pandemic.
In Thailand, where tourism makes up about 20 percent of the economy, the ban on foreign tourists has taken a heavy toll, especially in areas like the resort island of Phuket.
The Phuket hotel industry is seeking government approval to begin bringing in foreign tourists who would undergo quarantine for 14 days at designated hotels to start their holiday.
In other developments around the world:
India reported 83,883 new coronavirus cases on Thursday, breaking its own global record. It has the world’s third-highest number of cases and deaths after the United States and Brazil.
The Czech Republic reported 650 new coronavirus cases on Thursday, its highest single-day increase since the virus first appeared in the country in March.
Greece reported the first case of the coronavirus in the Moria camp for migrants on the Aegean island of Lesbos. The migration ministry said the facility would be locked down for two weeks as health inspectors tested other residents.
Virus fallout from the Sturgis motorcycle rally: A death in Minnesota, cases in South Dakota and more.
A Minnesota man is the first person known to have died of Covid-19 after attending the Sturgis Motorcycle Rally in South Dakota last month, a 10-day event where hundreds of thousands of people gathered, many showing little attention to social distancing or mask wearing. Health officials worried it could become a superspreader event.
State health officials in Minnesota confirmed the death, saying the man was in his 60s and had underlying health conditions; he had been hospitalized for several weeks, they said.
South Dakota has seen sharp increases in virus cases since the rally in Sturgis, a small town north of Rapid City in the western part of the state. And cases linked to the rally have been reported in a number of other states; Minnesota alone has confirmed more than 50 cases traced back to the rally, officials said.
Before Aug. 1, Meade County, which includes Sturgis, had reported just 71 cases over the pandemic’s first six months. By Sept. 1, the figure had shot up to 305, according to the State Health Department. That includes 26 cases detected when the city of Sturgis held a testing event for residents after the rally; 650 people took part.
South Dakota as a whole has reported more than 2,000 new cases in the past week, setting single-day records several times, according to a New York Times database.
Despite the surge of cases in South Dakota, Gov. Kristi Noem has said she has no plans to tighten restrictions in the state or issue a mask order.
“I won’t be changing my recommendations that I can see in the near future,” Ms. Noem, a Republican, said at the Sioux Falls Rotary Club on Monday. “I think this is where we expected to be. None of this is a surprise, and we will continue to evaluate and see what the future looks like.”
Another mass event, the South Dakota State Fair, is scheduled to open in Huron on Thursday and last through Labor Day.
“Exposure to Covid-19 is an inherent risk in any public location where people are present,” the fair warns on its website, adding, “By visiting the South Dakota State Fairgrounds, you voluntarily assume all risks related to exposure to Covid-19.”
New studies show inexpensive steroid drugs can help critically sick people survive Covid-19.
International clinical trials published on Wednesday confirmed hope that cheap, widely available steroid drugs can help seriously ill patients survive Covid-19.
After the release of the new data, the World Health Organization strongly recommended steroids for treatment of patients with severe or critical Covid-19 worldwide. But the agency recommended against giving the drugs to patients with mild disease.
The new studies include an analysis that pooled data from seven randomized clinical trials evaluating three steroids in over 1,700 patients. The study concluded that each of the three drugs reduced the risk of death.
That paper and three related studies were published in the journal JAMA, along with an editorial describing the research as an “important step forward in the treatment of patients with Covid-19.”
Corticosteroids should now be the first-line treatment for critically ill patients, the authors said. The only other drug shown to be effective in seriously ill patients — and only modestly at that — has been remdesivir.
Steroids like dexamethasone, hydrocortisone and methylprednisolone are often used by doctors to tamp down the body’s immune system, alleviating inflammation, swelling and pain. Many Covid-19 patients die not of the virus but of the body’s overreaction to the infection.
The analysis of pooled data found that steroids were linked with a one-third reduction in deaths among Covid-19 patients. Dexamethasone produced the strongest results: a 36 percent drop in deaths in 1,282 patients treated in three separate trials.
In June, researchers at Oxford University discovered that dexamethasone seemed to improve survival rates in severely ill patients. Researchers had hoped that other inexpensive steroids might help these patients.
Taken together, the new studies will bolster confidence in the use of steroids and address any lingering hesitancy on the part of some physicians, said Dr. Todd Rice, an associate professor of medicine and a critical care physician at Vanderbilt University School of Medicine.
“This shows us steroids are clearly beneficial in this population and should clearly be given, unless you absolutely can’t for some reason, which needs to be a pretty rare occasion,” he said.
Silvio Berlusconi, Italy’s former prime minister, tests positive.
Silvio Berlusconi, Italy’s former prime minister, tested positive for the coronavirus after a “precautionary check,” his staff announced on Wednesday.
Mr. Berlusconi, 83, is working from his mansion near Milan, where he will spend the isolation period, according to a prepared statement. He will continue his political activities, including daily interviews on television and social media to support his party’s candidates in the coming regional elections.
His physician, Dr. Alberto Zangrillo, told the Italian news agency ANSA that Mr. Berlusconi was asymptomatic.
Mr. Berlusconi, who is a media mogul, recently returned from a vacation at his villa in Sardinia, where he met political allies and friends, including Flavio Briatore, a businessman whose upscale nightclub gave rise to one of the island’s largest clusters of coronavirus infections. Mr. Briatore also tested positive last week.
Some regions of the country set up tents for rapid testing at ports, airports and train stations after many recent cases emerged among tourists returning from Sardinia. The island’s beaches and clubs were very busy this year, as Italians chose to spend their holidays nearer to home.
As the news spread that Mr. Berlusconi had the virus, politicians across the spectrum flooded social media with comments and good wishes.
“I want to send my best wishes to Silvio Berlusconi for a rapid recovery by all the Democrats’ community,” Nicola Zingaretti, the leader of the Democratic Party and one of the first political leaders to have the virus last March, wrote on Twitter. “He will strongly fight this battle, too.”
Matteo Salvini, leader of the right-wing League party, sent a “hug” to his “friend” via social media, while Giorgia Meloni of the extremist party Fratelli d’Italia, Brothers of Italy, called Mr. Berlusconi a “lion” on Twitter and wrote that he will “brilliantly overcome this, too.”
In March, when the pandemic hit Italy, Mr. Berlusconi was criticized for fleeing the country he once governed. He posted pictures of himself working from his daughter’s villa near Nice, France.
A judge orders the University of California to stop considering SAT or ACT scores because of the pandemic.
A state judge has barred the huge and influential University of California system from using SAT and ACT test scores in making decisions about which students to admit and whether to award scholarships, saying that students with disabilities would be unfairly hurt by having to take the tests under pandemic conditions.
“The barriers faced by students with disabilities have been greatly exacerbated by the Covid-19 pandemic, which has disrupted test-taking locations, closed schools and limited access to school counselors,” Judge Brad Seligman of Superior Court in Alameda County said in issuing a preliminary injunction on Tuesday.
The system’s governing board, the Board of Regents, voted in late May to phase out the use of standardized test scores in admissions for California students over the next four academic years. In the meantime, the system planned to look for a replacement test that would not be freighted with the accusations of bias against Black, Hispanic and poor students that have dogged the SAT and the ACT in recent years.
The judge’s decision came two months before the application deadline for admission in the fall of 2021. The system had already decided to make submission of test scores optional because of the pandemic, and some U.C. campuses, like Berkeley, had decided not to consider them in admissions.
Now, as a result of the injunction, the test scores cannot be used anywhere in the U.C. system for admission or scholarship decisions as long as the underlying lawsuit — a challenge to the tests’ legitimacy — is pending.
The University of California said in a statement that “an injunction may interfere with the university’s efforts to implement appropriate and comprehensive admissions policies and its ability to attract and enroll students of diverse backgrounds and experiences.” The statement said the university was considering whether to appeal.
The College Board, which oversees the SAT, said on Wednesday that there was “clear evidence” that standardized college entrance exams “increase enrollment for underrepresented students,” and that a larger than usual share of California students who took the test in August did so with an accommodation of some kind.
Beijing reopens to international flights.
International flights to Beijing resumed on Thursday for the first time in five months, after China halted the arrivals to block imported coronavirus cases.
Since late March, all international flights to the Chinese capital had been diverted to 12 other Chinese cities to prevent new outbreaks. Passengers underwent health screening and, in many cases, quarantined in those cities before continuing on to their destination.
Under the new policy announced by the Civil Aviation Administration on Wednesday, flights will be allowed from Austria, Cambodia, Canada, Denmark, Greece, Pakistan, Thailand and Sweden. An Air China flight from Phnom Penh, Cambodia, was the first one to arrive on Thursday morning.
International arrivals will be limited to about 500 a day during the trial period. Overseas passengers will still be required to be tested for the virus upon arrival and complete 14 days of quarantine in designated facilities. If three or more confirmed cases are found on any international flight to Beijing, the aviation agency said, future flights on that route could again be diverted to another city.
This week, the Chinese state news media reported that international flights in Wuhan, the central city where the coronavirus first appeared late last year, would also resume in mid-September.
The Coronavirus Outbreak ›
Frequently Asked Questions
Updated September 1, 2020
Why is it safer to spend time together outside?
- Outdoor gatherings lower risk because wind disperses viral droplets, and sunlight can kill some of the virus. Open spaces prevent the virus from building up in concentrated amounts and being inhaled, which can happen when infected people exhale in a confined space for long stretches of time, said Dr. Julian W. Tang, a virologist at the University of Leicester.
What are the symptoms of coronavirus?
- In the beginning, the coronavirus seemed like it was primarily a respiratory illness — many patients had fever and chills, were weak and tired, and coughed a lot, though some people don’t show many symptoms at all. Those who seemed sickest had pneumonia or acute respiratory distress syndrome and received supplemental oxygen. By now, doctors have identified many more symptoms and syndromes. In April, the C.D.C. added to the list of early signs sore throat, fever, chills and muscle aches. Gastrointestinal upset, such as diarrhea and nausea, has also been observed. Another telltale sign of infection may be a sudden, profound diminution of one’s sense of smell and taste. Teenagers and young adults in some cases have developed painful red and purple lesions on their fingers and toes — nicknamed “Covid toe” — but few other serious symptoms.
Why does standing six feet away from others help?
- The coronavirus spreads primarily through droplets from your mouth and nose, especially when you cough or sneeze. The C.D.C., one of the organizations using that measure, bases its recommendation of six feet on the idea that most large droplets that people expel when they cough or sneeze will fall to the ground within six feet. But six feet has never been a magic number that guarantees complete protection. Sneezes, for instance, can launch droplets a lot farther than six feet, according to a recent study. It’s a rule of thumb: You should be safest standing six feet apart outside, especially when it’s windy. But keep a mask on at all times, even when you think you’re far enough apart.
I have antibodies. Am I now immune?
- As of right now, that seems likely, for at least several months. There have been frightening accounts of people suffering what seems to be a second bout of Covid-19. But experts say these patients may have a drawn-out course of infection, with the virus taking a slow toll weeks to months after initial exposure. People infected with the coronavirus typically produce immune molecules called antibodies, which are protective proteins made in response to an infection. These antibodies may last in the body only two to three months, which may seem worrisome, but that’s perfectly normal after an acute infection subsides, said Dr. Michael Mina, an immunologist at Harvard University. It may be possible to get the coronavirus again, but it’s highly unlikely that it would be possible in a short window of time from initial infection or make people sicker the second time.
What are my rights if I am worried about going back to work?
After severe lockdowns in places like Wuhan and other restrictions nationwide at the start of the year, life in China has largely returned to normal as infections have subsided. On Thursday, the country reported zero domestically transmitted cases for the 18th day in a row. The Chinese mainland has had almost 93,000 cases and 4,634 deaths, according to a Times database.
Trump’s new coronavirus adviser has questioned masks and alarmed government scientists.
Dr. Scott W. Atlas has argued that the science of mask wearing is uncertain, that children cannot pass on the coronavirus and that the role of the government is not to stamp out the virus but to protect its most vulnerable citizens as Covid-19 takes its course.
Ideas like these, ideologically freighted and scientifically disputed, have propelled Dr. Atlas, a radiologist and senior fellow at Stanford University’s conservative Hoover Institution, into President Trump’s White House. Dr. Atlas is neither an epidemiologist nor an infectious disease expert, but his frequent appearances on Fox News and his ideological surety caught the president’s eye.
Mr. Trump has embraced Dr. Atlas even as he upsets the balance of power within the White House coronavirus task force with ideas that top government doctors and scientists find misguided — even dangerous — according to people familiar with the task force’s deliberations.
That may be the point.
“I think Trump clearly does not like the advice he was receiving from the people who are the experts — Fauci, Birx, etc. — so he has slowly shifted from their advice to somebody who tells him what he wants to hear,” said Dr. Carlos del Rio, an infectious disease expert at Emory University in Atlanta. He was referring to Dr. Anthony S. Fauci, the country’s leading infectious disease scientist, and Dr. Deborah L. Birx, the White House coronavirus response coordinator.
The Trump administration will ‘redirect’ money owed to the W.H.O.
As the United States withdraws from membership in the World Health Organization, the Trump administration will redirect $62 million still owed for this year’s dues to other health-related causes also under United Nations auspices, State Department officials announced on Wednesday.
Most of the redirected money will go to children’s immunization and influenza surveillance, officials said. But the United States Agency for International Development will continue with plans to give $68 million to the W.H.O. to support its work in Libya and Syria, and on polio eradication in Pakistan and Afghanistan.
The W.H.O. declined to comment, other than to refer reporters to statements made when the administration announced its intent to withdraw. At the time, Tedros Adhanom Ghebreyesus, the director general of the W.H.O., said the agency “regretted” Mr. Trump’s decision. “The United States of America has been a longstanding and generous friend to the W.H.O., and we hope it will continue to be so,” Dr. Tedros said.
On July 7, the Trump administration formally notified António Guterres, secretary general of the United Nations, that the United States would withdraw from the W.H.O. on July 6, 2021.
U.N. members are obliged to give a year’s notice of withdrawal and to pay all dues owed. The United States, which has historically been the agency’s largest supporter, was assessed 22 percent of the agency’s budget, or about $120 million; it had already paid $58 million, officials said, when the notice of withdrawal was delivered.
In 2019, the United States contributed about $553 million. That amount, far larger than the obligatory dues assessment, included voluntary donations to causes that the American government supports.
Secretary of State Mike Pompeo accused the W.H.O. on Wednesday of being ineffective and politically influenced as he defended the Trump administration’s rejection of a coordinated global initiative to distribute a coronavirus vaccine.
At least 172 countries are negotiating to join the so-called Covax program, the only worldwide effort among governments and manufacturers to approve and distribute a vaccine. So far, nine potential vaccines have been evaluated, and nine more are still being tested, according to the W.H.O.
At least 92 candidate vaccines are under active preclinical investigation in laboratories across the world, with 69 of them slated to begin clinical trials before the end of 2021, according to a database maintained by The Times.
In a statement, the W.H.O. called the United States a “vital partner” in global health efforts since the U.N. created the organization in 1948. “The response to this pandemic must be collective — no one is safe until everyone is safe,” the W.H.O. said.
Neymar and two other soccer players test positive after last week’s Champions League final.
Neymar, soccer’s costliest player, is among three players from the Paris St.-Germain team that played in last week’s Champions League final to test positive, becoming the latest high-profile soccer stars to do so ahead of the new season.
Neymar faces missing the start of his club’s latest campaign because of strict protocols that require players who have tested positive to isolate from the rest of the roster.
His team, which paid a record $263 million for the forward in 2017, confirmed that three of its players had tested positive, without providing names of the individual athletes. However, people familiar with the matter, speaking on condition of anonymity because the players were not identified publicly, said Neymar was among the three.
A spokeswoman for Neymar declined to comment. Media reports identified the other players as Ángel di María and Leo Parades, two teammates who accompanied Neymar on a vacation to the Spanish island Ibiza.
The cases put in doubt the availability of the three P.S.G. players for its first league game in defense of its French league title on Sept. 10. The virus has already disrupted the start of the French season, with the opening game between Marseille and Saint Etienne postponed after Marseille reported four positive tests.
P.S.G. said it would carry out more tests on players and staff over the next few days.
A German company began marketing an at-home antibody test.
A German company has begun marketing a coronavirus antibody test that allows patients to prick their fingers at home and mail in a test strip for evaluation, forgoing the need to visit a doctor.
The test, called AProof and made by Adversis Pharma, is among the first at-home antibody tests, according to Alexander Edwards, who tracks antibody testing at the University of Reading in Britain. He called the new test a “significant development.”
The test kit contains two finger-pricking lancets, a paper card and a return envelope addressed to a lab in Leipzig, Germany. The customer pricks a finger, places blood droplets on the paper, encloses it in a plastic bag and returns the sample to the lab.
Results are available online to people in Germany 24 to 48 hours after the lab receives the card, according to the company, and later to customers outside the country. The kit, developed with the University of Leipzig, costs $59 (or 49 euros).
Adversis Pharma said that the test is highly sensitive for coronavirus antibodies but acknowledged that false-positive results do occur.
Antibodies may develop days or weeks after infection with the coronavirus, and antibody testing is not recommended for diagnosis of the infection. Dr. Jörg Gabert, a director of the company, said he expected the test to be used by people who believe they might have been infected in the past but were not diagnosed.
It’s not clear what consumers should do about a positive antibody test. While researchers generally assume that antibodies confer some protection against the coronavirus, no one is certain how strong the immunity may be or how long it may last.
Antibodies to the virus decline within weeks or months of recovery from the infection, and scientists are struggling to understand what role another branch of the body’s disease-fighting machinery, so-called cellular immunity, plays in protecting people who have recovered.
Already scientists are finding cases of reinfection — patients who apparently recovered from the coronavirus but were infected again just weeks later. Until more is known, the World Health Organization has warned against using antibody tests to certify that people are immune.
Biden, in speech, faults Trump over reopening schools.
Joseph R. Biden Jr., the Democratic presidential nominee, said Wednesday that President Trump was hurting American parents, teachers and schoolchildren with his push for schools to reopen amid the pandemic.
“President Trump still doesn’t have any real plan for how to open our schools safely,” Mr. Biden said in a short speech in Wilmington, Del., after receiving a briefing from a group of experts. “No real plan for how to help parents feel secure for their children. He’s offering nothing but failure and delusions. From the start to finish, the American families and our children are paying the price for his failures.”
The Biden campaign said that Mr. Biden and his running mate, Senator Kamala Harris of California, were urging Mr. Trump to work with congressional leaders to provide emergency funding for schools of at least $200 billion. Mr. Biden and Ms. Harris also would direct the Federal Emergency Management Agency to make available federal aid to K-12 schools to support their reopening and operations amid the crisis, the campaign said.
Mr. Trump has demanded that schools reopen this fall and threatened to cut federal funding for school districts that defied his wishes. But his effort to pressure schools did not have the effect he desired, and many districts decided to begin the school year with remote instruction.
Before Mr. Biden’s speech, he and his wife, Jill Biden, a community college professor, were briefed by a group of experts, including Sylvia Mathews Burwell, who served as secretary of health and human services for President Barack Obama and is now the president of American University, and Linda Darling-Hammond, the president of the California State Board of Education.
Symone Sanders, a senior adviser for the Biden campaign, said Mr. Trump was “barreling forward trying to reopen schools because he thinks it will help his own re-election.”
“We believe this is a key contrast for voters,” Ms. Sanders said. “President Trump, who continues to ignore the science and has no plan to get the virus under control, and Joe Biden, who is working with the experts and putting together an effective plan to beat the virus and reopen schools safely.”
Elsewhere in the United States:
In New York City, where indoor dining remains prohibited, Mayor Bill de Blasio said on Wednesday that he felt like the industry was owed more clarity this month on a possible timeline and set of standards for reopening. “We need to decide that in the next few weeks,” he said, “whether it’s good news or bad news.”
A day after New York City’s school system delayed the start of classes, Gov. Philip D. Murphy of New Jersey said that state’s schools were still on track to reopen next week. Mr. Murphy said that 434 of New Jersey’s school districts were expected to open with a hybrid model that combined in-person and remote learning, while 68 will start with all in-person instruction, 242 with only remote learning, and 22 with “some combination.”
As Iowa has faced the most new cases per capita of any state over the last seven days, Joni Ernst, the state’s junior senator and a Republican in a tight race for re-election, echoed a debunked conspiracy theory that coronavirus death tolls were being greatly inflated and suggested that health care providers had a financial motive to falsify cases.
A Trump administration order could allow millions of renters who have suffered financially because of the pandemic to avoid eviction through the end of the year. While the new policy, which goes into effect on Sept. 4, could bring relief to some American renters, there is a lot of fine print about who is eligible for the benefit (you must meet a five-pronged test), whether you will be expected to pay everything owed to the landlord in January (maybe) and what kind of penalties the landlord could face if the policy is ignored (depending on the situation, up to $250,000 or a year in jail or both).
Dwayne Johnson, the actor and former wrestler known as the Rock, announced on Instagram on Wednesday that he and his family had recently tested positive for Covid-19. Mr. Johnson said they had become infected around two and a half weeks ago, from “very close family friends.” Mr. Johnson called it “one of the most challenging and difficult things we have ever had to endure as a family,” but added that he and his family were now “on the other end of it” and were healthy and no longer contagious.
Art Basel Miami Beach has been canceled for 2020, organizers said Wednesday, citing the uncertainty of the pandemic. The next edition of the art fair, which had been scheduled for Dec. 3 to 6, will now take place from Dec. 2 to 5 next year. Art Basel’s two other annual shows, which were planned for Hong Kong in March and Basel, Switzerland, in September, were canceled earlier this year.
A superspreader event on a bus focuses scientists on the likelihood of airborne transmission.
In late January, as the new coronavirus was beginning to spread from China’s Hubei Province, a group of lay Buddhists traveled by bus to a temple ceremony in the city of Ningbo — hundreds of miles from Wuhan, center of the epidemic.
A passenger on one of the buses had recently dined with friends from Hubei. She apparently did not know she carried the coronavirus. Within days, 24 fellow passengers on her bus were also found to be infected.
It did not matter how far a passenger sat from the infected individual on the bus, according to a study published in JAMA Internal Medicine on Tuesday. Even passengers in the very last row, seven behind the infected woman, caught the virus.
The incident adds to a large body of evidence indicating that the coronavirus can be transmitted by tiny particles that linger in the air, and not just through large respiratory droplets that fall quickly to the ground.
The new study “adds strong epidemiological evidence that the virus is transmitted through the air, because if it were not, we would only see cases close to the index patient — but we see it spread throughout the bus,” said Linsey Marr, a professor of civil and environmental engineering at Virginia Tech and a leading expert on airborne viruses.
The potential for airborne transmission in close confined spaces raises concern about the winter months, when people will be spending more time indoors, Dr. Marr said. Her advice: “Avoid crowded indoor spaces where people are not wearing masks and the ventilation is poor.”
Reporting was contributed by Trip Gabriel, Michael Gold, Anemona Hartocollis, Jennifer Jett, Sheila Kaplan, Thomas Kaplan, Juliana Kim, Niki Kitsantonis, Isabella Kwai, Ron Lieber, Benjamin Novak, Richard C. Paddock, Tariq Panja, Gaia Pianigiani, Roni Caryn Rabin, Matt Richtel, Campbell Robertson, Christopher F. Schuetze, Michael D. Shear, Dera Menra Sijabat, Daniel E. Slotnik, Sheryl Gay Stolberg, Eileen Sullivan, Jim Tankersley, Katie Thomas, Neil Vigdor, Mark Walker, Allyson Waller, Katherine J. Wu, Noah Weiland and Elaine Yu.