Coronavirus: South Korea closes most schools in Seoul area; first confirmed case of reinfection

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South Korea ordered most schools in capital Seoul and its surrounding regions to shut due to a resurgence in coronavirus cases.

Scientists are expressing some doubts about the Food and Drug Administration's emergency use authorization for convalescent plasma as a treatment for Covid-19 patients. In a Sunday news briefing, President Donald Trump touted the treatment as a "breakthrough." Former FDA chief Dr. Scott Gottlieb told CNBC that while there was enough data to justify the authorization, the treatment is not a "home run."

Here were some of the biggest developments on Monday:

The following data was compiled by Johns Hopkins University:

  • Global cases: More than 23.6 million
  • Global deaths: At least 813,265
  • Countries with the most cases: United States (more than 5.7 million); Brazil (more than 3.6 million); India (more than 3.1 million); Russia (at least 959,016) and South Africa (at least 611,450)

Usain Bolt tests positive for coronavirus

Usain Bolt of Jamaica celebrates after winning gold in the Men's 100 metres final during day two of the 15th IAAF World Athletics Championships Beijing 2015 at Beijing National Stadium on August 23, 2015 in Beijing, China.
VCG | Visual China Group | Getty Images

Jamaica's health ministry has confirmed Usain Bolt, the world's fastest man, has tested positive for the coronavirus. 

The world-record sprinter and eight-time Olympic gold medalist is self-isolating at his home in Jamaica. Bolt had posted a video message on social media before testing positive for the infection on Monday, saying he had quarantined himself "just to be safe."

Bolt said he took the coronavirus test on Saturday, one day after he celebrated his 34th birthday mask-free. — Sam Meredith

AstraZeneca begins antibody drug trial for prevention and treatment of Covid-19

AstraZeneca's building in Luton, Britain.
Tim Ireland | Xinhua News Agency | Getty Images

British pharmaceutical giant AstraZeneca has started testing an antibody-based drug for treatment and prevention of Covid-19, with the first participants of the trial already receiving doses. 

The London-listed firm, one of the world leaders in the global pursuit to develop a safe and effective vaccine, said the trial would include up to 48 healthy participants aged between 18 to 55-years-old. 

"This trial is an important milestone in the development of our monoclonal antibody combination to prevent or treat Covid-19," Mene Pangalos, executive vice president of biopharmaceuticals research and development at Astra, said in a statement.

"This combination of antibodies, coupled to our proprietary half-life extension technology, has the potential to improve both the effectiveness and durability of use in addition to reducing the likelihood of viral resistance," Pangalos said. — Sam Meredith

South Korea closes most schools in Seoul area due to resurgence

Pedestrians wearing face masks wait to cross a street in Seoul on August 24, 2020.
Ed Jones | AFP | Getty Images

South Korea ordered most schools in capital Seoul and its surrounding areas to close due to a resurgence in coronavirus cases.

The Korea Centers for Disease Control and Prevention reported 280 new coronavirus cases, bringing the country's total number of infections to 17,945. The death toll stood at 310.

South Korea won praise for its strategy in handling the outbreak earlier this year when it managed to bring the virus under control without a total shutdown. But cases have risen recently and authorities said last week that the outbreak is back "in full swing" after members of a church attended a political demonstration, Reuters reported.

South Korean health authorities have urged people to stay home and limit travel as most of the new cases come from densely populated Seoul, sparking concerns that the country is on the verge of a nationwide outbreak, Reuters reported.

All students other than high school seniors in the cities of Seoul and Incheon and the province of Geonggi will take online classes until Sept. 11, Reuters reported, citing the Ministry of Education. — Huileng Tan

South Korea may benefit most from China's recovery, ANZ says

South Korea may be the economy that can benefit the most from China's ongoing recovery, said Sanjay Mathur, chief economist for Southeast Asia and India at Australian bank ANZ. 

He explained that the South Korean economy is "doing quite alright" thanks to trade with China. South Korea ships around one quarter of its exports to China, where demand has improved, he told CNBC's "Squawk Box Asia."

"Clearly if one were to pick up an economy that is quite dependent on China and an economy that China can substantially support to sort of come out of this situation is really South Korea this point in time," said Mathur.

"There are other channels in other economies ... which are also dependent on China, for example the tourism sector in Thailand, but those are things that are not going to change," he added.

South Korea is battling a resurgence in coronavirus cases, which led capital city Seoul — where many new infections were found — to mandate mask wearing in both indoor and outdoor public spaces, reported Reuters.

Mathur said the country has implemented fiscal stimulus in a "timely manner." That means that barring a "massive" resurgence in infections, South Korea can wait and see how earlier measures play out, he explained. — Yen Nee Lee

Delta says furlough notices going to 1,941 pilots

Delta Air Lines is planning to furlough 1,941 pilots in October if it can't reach agreements to cut costs with the labor union, the airline says.

Earlier this summer, Delta warned 2,558 of its pilots about potential furloughs this fall. The number was lowered by more than 1,800 pilots who took early retirement packages, but an airline executive warned it is not enough to avoid furloughs. Delta last month said remaining pilots could avoid furloughs altogether with a 15% cut to minimum pay.

"With approximately 11,200 active pilots still on the roster following the September 1 [voluntary early retirement] departures, we are simply overstaffed, and we are faced with an incredibly difficult decision," John Laughter, Delta's senior vice president of flight operations, wrote in a memo to pilots.

Laughter said the company will need about 9,450 pilots for summer 2021, "which we expect will be the peak flying for the next 12-18 months." —Leslie Josephs

Former Google employees are launching a 'school' for pandemic-affected university students

James Cashen decided against returning to Cornell University in favor of a work-preparation education.
Source: James Cashen

Current and former Google employees are proposing a new kind of school for students missing out on a regular college experience this year due to Covid-19.

The Xoogler School — named after a Google alumni network — is an eight-week program consisting of former Google employees and executives like former Google Cloud president Amit Singh who will mentor college students. The virtual school, that will commence mid-September, will offer a speaker series and one-on-one mentorships for rising juniors and seniors who are considering taking a gap year due to school changes.

Xoogler School staffers say that, unlike other online vocational schools, this school will offer a variety of classes on potential tech careers — as well as non-tech — tapping its vast pool of 9,000 Google alumni. Founder Christopher Fong said he wants the school to fill the gap between university education and the real-world experiences at companies like Google. —Jennifer Elias

Scientists have doubts about Trump-touted plasma treatment

Scientists and public health officials said they are skeptical that convalescent plasma, hailed by President Donald Trump as a "breakthrough," is an effective treatment for patients hospitalized with Covid-19.

The Food and Drug Administration said Sunday it granted an emergency use authorization, allowing health-care providers in the U.S. to use the plasma to treat patients hospitalized with Covid-19. The agency said it was reasonable to believe the treatment may be effective in treating Covid-19 patients, and the known and potential benefits outweigh the known and potential risks.

However, scientists and health officials say more data from randomized controlled trials, which are considered the "gold standard" in science, is still needed to know whether it is safe and effective. Results of a study by the Mayo Clinic that the FDA cited in its authorization suggested the plasma may reduce mortality in some hospitalized patients. The study had no placebo group to compare the results, making it hard to determine whether the treatment actually worked.

"The EUA was granted without a published peer review study and rolled out with political fanfare," said Lawrence Gostin, a professor and faculty director of the O'Neill Institute for National and Global Health Law at Georgetown University. —Berkeley Lovelace Jr.

Google searches for anxiety soared amid the pandemic, study finds

People searched for severe anxiety-related information at record highs beginning in March when the coronavirus pandemic was first declared a national emergency, according to a new study conducted by the Qualcomm Institute at the University of California San Diego and published in JAMA Network Open that analyzed Google Trends dating back 16 years. 

Anxiety-related searches were roughly 11% higher than usual over the 58 days after President Donald Trump declared a national emergency on March 13, according to the researchers. The searches spiked around key news events, rising 17% above normal from March 16, when national social distancing guidelines were first imposed, to April 14, a few days after the U.S. passed Italy for the most deaths.

"In practical terms, over the first 58 days of the COVID-19 pandemic there were an estimated 3.4 million total searches related to severe acute anxiety in the United States. In fact, searches for anxiety and panic attacks were the highest they've ever been in over 16 years of historical search data," Benjamin Althouse, a principal scientist at the Institute for Disease Modeling, said in a statement. —Noah Higgins-Dunn

First reinfection is documented in Hong Kong, researchers say

Hong Kong researchers reported what appears to be the first confirmed case of coronavirus reinfection, health news publication STAT reported.

A 33-year-old man who was initially infected with Covid-19 in late March seemed to contract the virus again four and a half months later while traveling in Europe, according to the report. The case raises questions about how effective a vaccine might be in protecting against the virus over the long-term. Other scientists cautioned, however, that the extent to which the case pointed to broader concerns about reinfection was uncertain.

"There's been more than 24 million cases reported to date," Maria Van Kerkhove, a coronavirus expert at the World Health Organization, said at a briefing, when asked about the Hong Kong paper. "And we need to look at something like this at a population level." —Terri Cullen

NFL had 77 apparently false positive coronavirus tests from NJ lab

The National Football League had 77 positive Covid-19 tests re-examined by a New Jersey lab after false positives, and all of those tests came back negative, the Associated Press reported.

The NFL uses BioReference for all of its Covid-19 testing and five labs nationwide service the 32 teams to ensure teams get results quickly. Only the New Jersey facility had the false positives this weekend, according to the Associated Press report.

"On August 22, BioReference Laboratories reported an elevated number of positive Covid-19 PCR test results for NFL players and personnel at multiple clubs," Executive Chairman Dr. Jon Cohen said in a statement to CNBC. "Our investigation indicated that these were most likely false-positive results, caused by an isolated contamination during test preparation in the New Jersey laboratory. Reagents, analyzers and staff were all ruled out as possible causes and subsequent testing has indicated that the issue has been resolved." —Melodie Warner

Not a home run, but we're only 'looking for singles and doubles,' says Dr. Gottlieb

Former FDA chief Scott Gottlieb on coronavirus plasma treatment
Former FDA chief Scott Gottlieb on coronavirus plasma treatment

The coronavirus plasma treatment approved by the Food and Drug Administration for emergency use doesn't look like a home run, Dr. Scott Gottlieb told CNBC on Monday.

"I think that this could be beneficial. It might be weakly beneficial," the former FDA chief in the Trump administration said on "Squawk Box."

"It doesn't look like a home run, but right now we're looking for singles and doubles" in treating Covid-19 patients," he said.

The Mayo Clinic is conducting studies on convalescent plasma's effectiveness on the coronavirus. The century-old treatment was used on patients during the 1918 flu pandemic. —Kevin Stankiewicz 

Disclosure: Scott Gottlieb is a CNBC contributor and is a member of the boards of Pfizer, genetic-testing start-up Tempus and biotech company Illumina. 

Dow jumps more than 200 points as market builds on record-setting week

U.S. stocks opened higher as gains in tech shares and some developments on coronavirus treatments drove the bullish sentiment, reports CNBC's Fred Imbert and Yun Li. 

The Dow Jones Industrial Average jumped 219 points, or 0.8%. The S&P 500 rose 0.8% and Nasdaq was up 1.3%. —Melodie Warner 

The latest on new U.S. cases by state

Chinese e-commerce giants get a boost

E-commerce and food delivery giants in China are seeing a sustained boost, as more consumers move online and businesses seek to digitize, even as coronavirus restrictions are lifted in large parts of the country, CNBC's Arjun Kharpal reports.

"Post COVID-19, the pace of digitization continues to accelerate and the shift from offline to online, in part