South Korea new cases most since March; Abbott wins U.S. authorization for $5 test

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South Korea reported 441 new coronavirus cases, the highest since March, as the country's health ministry flagged risks from new clusters at call centers and logistics warehouses.

Turmoil over the recent move by the Centers for Disease Control and Prevention to revise its testing guidance for people without symptoms escalated Wednesday as the governors of New York and California both said they would not be following the new guidance. The CDC now says people who came into contact with someone who tested positive for Covid-19 "do not necessarily need a test," a declaration that New York Gov. Andrew Cuomo criticized as "political propaganda." Assistant Secretary for Health Adm. Brett Giroir, who leads the Trump administration's testing effort, denied that there was any push from the Trump administration to make the change.

Here are some of today's biggest developments: 

The following data was compiled by Johns Hopkins University:

  • Global cases: More than 24 million
  • Global deaths: At least 824,664
  • Countries with the most cases: United States (more than 5.8 million); Brazil (more than 3.7 million); India (more than 3.2 million); Russia (at least 968,297) and South Africa (at least 615,701)

South Korea reports 441 new cases — the most since March

A temple worker attaches name cards with wishes of Buddhist followers to lotus lanterns during a celebration ceremony for Buddha's Birthday at Jogye temple in Seoul on May 30, 2020.
Jung Yeon-je | AFP | Getty Images

South Korea reported 441 new coronavirus cases — the highest since March as the country's health ministry flagged new clusters at call centers and logistics warehouses.

While authorities say the recent surge in cases is due to outbreaks in a church and at an anti-government rally this month, they also warned about the possibility of new clusters in densely packed workplaces.

At least 80% of the infections in the past week are from the densely populated Seoul metropolitan area, Reuters reported citing Health Minister Park Neung-hoo.

On Thursday, South Korea urged business to let employees work from home.

The new cases bring South Korea's total number of infections of 18,706 and the death toll to 313. —Huileng Tan

Abbott wins U.S. authorization for $5 rapid antigen test

Abbott Laboratories said it won U.S. marketing authorization for a portable coronavirus antigen test that can deliver results within 15 minutes, Reuters reported.

The test, which will sell for $5, is about the size of a credit card and does not require additional equipment, the news agency said. It also uses a less invasive nasal swab than traditional lab tests, Reuters reported citing Abbott executives.

Abbott expects to ship tens of millions of tests in September and up to 50 million tests a month beginning in October, the news agency said. —Huileng Tan

California governor says new reopening guidelines to come Friday

California Gov. Gavin Newsom said during a press briefing that the state will release new guidelines on Friday for reopening certain counties in the state. He said the new "framework" will take into consideration feedback from local health officials. The new guidance comes after the state reported a resurgence in cases over the summer after its initial reopening earlier this year. 

Newsom said that 34 of the state's 58 counties are now on its so-called monitoring list, which brings more restrictions on businesses and schools. California has reported a decline in hospitalizations and intensive-care admissions over the last 14 days, though the positivity rate, or the percent of total tests returning positive, has remained steady near 6.1%. 

Newsom also announced a new partnership with PerkinElmer aimed at expanding California's Covid-19 testing capacity and reducing the price of testing. The new partnership should also reduce wait time for test results from up to seven days, which is the current average, to about one or two days, he said. —Noah Higgins-Dunn

CDC proposes guidelines for distributing vaccine in the U.S.

The Centers for Disease Control and Prevention proposed guidelines for distributing a coronavirus vaccine in the United States if and when one is approved for public use.

As drugmakers race to find a safe and effective vaccine by the end of the year, scientists and infectious disease experts worry about who will get the vaccine first and how. The U.S. will initially have a limited supply of vaccine doses that won't be widely available until "several months" into 2021, according to Dr. Anthony Fauci, the nation's leading infectious disease expert.

The CDC guidelines, unveiled during a presentation at the CDC's Advisory Committee on Immunization Practices meeting, would prioritize health-care workers, essential personnel and vulnerable Americans, like the elderly and those with underlying health conditions. —Berkeley Lovelace Jr.

Fed's Powell expected to discuss pandemic era tool to long-running problem of low inflation

Federal Reserve Chairman Jerome Powell speaks Thursday at the Fed's annual Jackson Hole symposium, and he's widely expected to offer a new way to fight low inflation.

Powell is not looking to spike inflationm, but it has been running below the Fed's 2% target for most of the past decade. Low inflation suggests a slower pace of growth and also a lack of pricing power.

Powell is expected to offer a new policy, where the Fed would have an average inflation target, which could be a band above and below 2%. That means it would let inflation run higher than normal for a period, until it sees that it is sustainable. Traditionally, the Fed uses interest rate hikes to stop inflation from rising and it may hold off on rate moves temporarily. 

The anticipated policy move, expected at the Fed's September meeting, is seen as dovish as it could signal the Fed is sticking to its policy of zero rates for a lot longer. The Fed has used an extraordinary array of tools to fight the coronavirus and this would be the latest if it adopts it. —Patti Domm

BHP Group CEO says ‘pretty solid V-shaped recovery’ underway in China

As the global economy attempts to bounce back from Covid-19, BHP Group CEO Mike Henry said a "pretty solid V-shaped recovery" is underway in China.

"The [Chinese] government has stepped in with some stimulus that we expect is going to create further momentum through to next calendar year. So things are looking pretty positive and pretty resilient," he told CNBC's "Squawk on the Street."

While he expects a "pretty sharp uptick" in global growth next year, he said it will likely take the world two to three years to return to pre-coronavirus levels of economic activity.

As the world's largest mining company, BHP is heavily dependent on global growth. Shares of the company are flat year to date. —Pippa Stevens 

Trump could act to avoid thousands of airline layoffs, White House says

President Donald Trump could take executive action to avoid thousands of airline furloughs, said White House Chief of Staff Mark Meadows. The comments came a day after American Airlines said it plans to cut 19,000 employees in October, after the terms of federal aid expires.

Airline labor unions and executives have urged lawmakers to extend $25 billion in federal aid that protects industry jobs through Sept. 30. The plan has gained bipartisan support in Congress and from President Trump but lawmakers haven't yet come to an agreement on another national coronavirus relief package, which could include the airline aid.

"If Congress is not going to work, this president is going to get to work and solve some problems. So hopefully, we can help out the airlines and keep some of those employees from being furloughed," Meadows said in an interview with Politico. —Leslie Josephs

New York Gov. Cuomo rips into CDC as Trump’s political tool

New York Gov. Andrew Cuomo said the state won't be following the Centers for Disease Control and Prevention's new guidance on coronavirus testing and urged others to do the same.

His remarks come after the CDC quietly revised its recommendations on testing for the coronavirus to downplay the importance of testing people without symptoms. The CDC previously recommended testing for anyone with a "recent known or suspected exposure" to the virus even if they did not have symptoms. The previous guidance cited "the potential for asymptomatic and pre-symptomatic transmission" as a reason why people without symptoms who were exposed to the virus should be "quickly identified and tested."

"We're not going to follow the CDC guidance. I consider it political propaganda. I would caution private companies against following the CDC guidance. I think it is wholly indefensible on its face. I think it is inherently self-contradictory. It is the exact opposite of what the CDC has been saying," Cuomo said on a conference call with reporters. "So either the CDC is schizophrenic or they are admitting error in their first position or this is just political dictations." 

Dr. Howard Zucker, New York state's health commissioner, called the change "indefensible" and said it "makes absolutely no sense."

"I have spoken with the scientists at the CDC, and they say it's political," Zucker added. —Will Feuer

WHO says it's possible that people who’ve recovered from the virus can get it again

WHO official: It's rare but possible to see reinfection in people who recovered from the coronavirus
WHO official: It's rare but possible to see reinfection in people who recovered from the coronavirus

Dr. Maria Van Kerkhove, head of the WHO's emerging diseases and zoonosis unit, said during a live Q&A session that it's possible people who have recovered from Covid-19 could be reinfected again, though so far it's rare. On Monday, researchers released a study that found what appears to be the first documented cases of Covid-19 reinfection in a 33-year-old man.

"It doesn't mean that it's happening a lot, we know that it's possible," Kerkhove said. "It is something that we knew could be possible based on our experience with other human coronaviruses." 

Kerkhove reiterated that no matter whether someone has been infected or not, they should continue following suggested social distancing guidelines, wearing face coverings and follow other recommended health precautions.

"Yes, it's possible that we could start to see reinfection but you know we have the tools in place that can prevent people from getting infected," Kerkhove said.  —Noah Higgins-Dunn

Moderna says vaccine shows promising results in elderly patients

Biotechnology company Moderna protocol files for COVID-19 vaccinations are kept at the Research Centers of America in Hollywood, Florida, on August 13, 2020.
Chandan Khanna | AFP | Getty Images

Moderna's potential Covid-19 vaccine generated a promising immune response in an early-stage trial of elderly patients, according to new preliminary data. 

The company tested its vaccine on 10 adults between the ages of 56 and 70, and 10 elderly adults aged 71 and older. Each participant received two 100 microgram doses of the vaccine 28 days apart.

The volunteers produced neutralizing antibodies, which researchers believe are necessary to build immunity to the virus, and killer T-cells, Moderna said. Additionally, the antibodies that were produced were higher than those seen in people who have recovered from Covid-19. The vaccine also appeared to be well tolerated. Some patients reported fatigue, chills, headaches and pain at the injection site, though the majority of symptoms resolved within two days, the company said. –Berkeley Lovelace Jr.

Pandemic may be a 2020 event if U.S. remains vigilant, says Gottlieb

Gottlieb: There's a risk for an uptick in Covid cases in the fall, but hopes pandemic is 'a 2020 event'
Dr. Scott Gottlieb warns of fall Covid uptick, but hopes pandemic is 'a 2020 event'

Former Food and Drug Administration chief Dr. Scott Gottlieb told CNBC he believes the pandemic can really be "a 2020 event," stressing the need for people to take proper precautions to slow the spread of the virus. 

"As we get into 2021, we're going to have enough exposure in the general population, enough awareness, people will be taking precautions in perpetuity for a period of time, and hopefully a vaccine at some point in early 2021, that we get this behind us," Gottlieb said on "Squawk Box."

Expressing concerns about a potential rise in cases this fall and winter, Gottlieb said Americans must continue to some level of vigilance with masks and other public health strategies to help keep the virus at bay. He also expressed optimism that more rapid coronavirus tests will come onto the market to help aid in the U.S. pandemic response. 

"So things are going to change, I think, very quickly in terms of what we have available to us, the technology, to combat this," he said. —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. 

World Economic Forum postpones 2021 summit in Davos

The World Economic Forum said in a release it has decided to postpone its upcoming meeting in Davos, Switzerland, out of caution and to prevent the spread of Covid-19. The next iteration of the annual meeting, originally scheduled for January 2021, will be rescheduled to "early next summer," according to Adrian Monck, a spokesman at the Forum.

"The decision was not taken easily, since the need for global leaders to come together to design a common recovery path and shape the 'Great Reset' in the post-Covid-19 era is so urgent," Monck said in a statement. "However, the advice from experts is that we cannot do so safely in January." —Thomas Franck

U.S. toll hovers near 1,000 deaths a day

CDC quietly revises guidance on asymptomatic testing

The Centers for Disease Control and Prevention has quietly revised its guidance on testing for the coronavirus and it no longer recommends testing for everyone who's been exposed to the virus, saying people who don't have symptoms "do not necessarily need a test."

The agency previously recommended testing for anyone with a "recent known or suspected exposure" to the virus even if they did not have symptoms. The CDC's previous guidance cited "the potential for asymptomatic and pre-symptomatic transmission" as a reason why people without symptoms who were exposed to the virus be "quickly identified and tested." 

"If you have been in close contact (within 6 feet) of a person with a Covid-19 infection for at least 15 minutes but do not have symptoms... You do not necessarily need a test unless you are a vulnerable individual or your health care provider or State or local public health officials recommend you take one," the CDC's site now says. "A negative test does not mean you will not develop an infection from the close contact or contract an infection at a later time." —Will Feuer

Prepping for monster Hurricane Laura amid the pandemic

Hurricane Laura seen from the International Space Station.
Chris Cassidy | NASA

As powerful Category 3 Hurricane Laura approached the U.S. Gulf Coast, more than half a million people were ordered on Tuesday to evacuate along the Texas-Louisiana state line, the Associated Press reported. The storm, which is expected to bring catastrophic damage to the region Wednesday and Thursday, also raised concerns about the danger from the spread of coronavirus. 

Officials were urging evacuees to stay with relatives or in hotel rooms farther inshore to avoid spreading Covid-19. Evacuation buses were stocked with protective equipment and disinfectant, the wire service reported. Fewer passengers were boarding the buses, as well, in an effort to social distance.

Shelters were also separating cots farther apart to try to limit infections, AP reported. Evacuees were told to bring just one bag of personal belongings each, as well as masks. —Terri Cullen

Hurricane Laura barrels toward the U.S. Gulf Coast
Hurricane Laura barrels toward the U.S. Gulf Coast

New Jersey gyms to reopen at 25% capacity, governor says

New Jersey Gov. Phil Murphy tweeted that gyms in the state will be allowed to reopen at 25% capacity beginning Sept. 1. In the tweet, Murphy said that masks will be required. 

Murphy's order comes after New York Gov. Andrew Cuomo announced gyms could reopen beginning this week at 33% capacity. Some New Jersey gym owners have previously rallied against Murphy's restrictions on small businesses, drawing national attention. —Noah Higgins-Dunn

Here are the perilous ways the virus attacks the body

It's been almost eight months since scientists first identified the virus, and doctors are still discovering new symptoms that can ravage the body and leave damage months after recovering from Covid-19.

Doctors know Covid-19 can be unpredictable, stressing virtually every system in the body, including the heart, kidneys and the brain. Some patients may suffer long-lasting nerve damage that impacts their ability to walk or smell, while others have continuous coughing fits and struggle to breathe, scientists and health officials say. A coronavirus infection may trigger rashes or hives on the skin or even structural changes in the brain, they said. 

"We have to come to grips that Covid might kill me, but it could also debilitate you over a significant period of time. And therefore we have to take it seriously," Dr. Mike Ryan, executive director of the World Health Organization's health emergencies program, said during a Q&A on July 29. –Berkeley Lovelace Jr.

University of Iowa president blames businesses for outbreak

University of Iowa President Bruce Harreld in an open letter criticized local Iowa City businesses for the growing coronavirus outbreak and implored them to comply with the governor's proclamation on social distancing in order to bring spread under control.

"Over the past two weeks, I have been exceedingly disappointed in some of the downtown Iowa City businesses and your choices to disregard the proclamation from the governor," he wrote in the letter. "These actions have led to an increase in the transmission of COVID-19 in our community, and we, as a community, will now have to respond."

On Monday, the beginning of classes, the University of Iowa announced that 111 students and staff reported that they have tested positive for Covid-19 some time during the past week. Also on Monday, Dan Diekema, director of the Division of Infectious Diseases at the University of Iowa, tweeted that "We have a COVID-19 outbreak in Iowa City."

—Will Feuer

Coronavirus concerns fall in swing states, CNBC/Change Research poll finds

President Donald Trump arrives for a photo opportunity with sheriffs from across the country on the South Lawn of the White House in Washington.
Erin Scott | Reuters

Voters' concerns about the coronavirus have fallen and President Donald Trump's approval rating has ticked higher in six swing states over the last two weeks, according to a new CNBC/Change Research poll. 

In Arizona, Florida, Michigan, North Carolina, Pennsylvania and Wisconsin, 66% of likely voters said they have serious concerns about Covid-19, the survey released Wednesday found. That's down from 69% in a poll taken two weeks earlier. The share of respondents who said they have "very serious" concerns about the coronavirus dropped to 45% from 49%.

At the same time, 48% of voters in the states said they approve of the job Trump is doing, while 52% disapprove. Two weeks ago, 46% of respondents said they approved of the job Trump is doing, versus 54% who disapproved. 

On how the president has handled the coronavirus, approval rose to 47%, the highest since mid-May. Earlier this month, only 44% of respondents said they approved of how Trump is handling Covid-19. —Jacob Pramuk

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