narvikk/iStockBy MORGAN WINSOR and EMILY SHAPIRO, ABC News

(NEW YORK) — A pandemic of the novel coronavirus has now killed more than 850,000 people worldwide.

Over 25.4 million people across the globe have been diagnosed with COVID-19, the disease caused by the new respiratory virus, according to data compiled by the Center for Systems Science and Engineering at Johns Hopkins University. The criteria for diagnosis — through clinical means or a lab test — has varied from country-to-country. Still, the actual numbers are believed to be much higher due to testing shortages, many unreported cases and suspicions that some national governments are hiding or downplaying the scope of their outbreaks.

Since the first cases were detected in China in December, the virus has rapidly spread to every continent except Antarctica.

The United States is the worst-affected country, with more than six million diagnosed cases and at least 183,598 deaths. California has the most cases of any U.S. state, with more than 712,000 people diagnosed, according to Johns Hopkins data. California is followed by Texas and Florida, with over 632,000 cases and over 623,000 cases respectively.

Nearly 170 vaccine candidates for COVID-19 are being tracked by the World Health Organization, six of which are in crucial phase three trials.

Here’s how the news is developing Tuesday. All times Eastern:

Sep 01, 11:03 am
Schools in Greece to reopen Sept. 14

Schools in Greece will reopen on Sept. 14, the government announced Tuesday.

Masks will be mandated indoors. Students in third grade and younger will be taught how to wear their masks properly.

Greece has 10,317 COVID-19 cases and 266 deaths, according to Johns Hopkins University data.

“The pandemic’s evolution is dynamic,” Greek Education Minister Niki Kerameus told reporters in Athens on Tuesday, adding that measures will be adjusted as necessary on local, regional and national levels.

“We will not hesitate to adopt measures that are more austere depending on the progression of the pandemic,” Kerameus said.

ABC News’ Christine Theodorou contributed to this report.

Sep 01, 11:00 am
Alaska, Montana added to New York’s travel advisory list

Alaska and Montana have been added to New York’s travel advisory list, which requires people traveling to the Empire State from a high-coronavirus area to quarantine for two weeks, New York Gov. Andrew Cuomo announced Tuesday.

The states and territories currently on New York’s list are: Alaska, Alabama, Arkansas, California, Florida, Georgia, Guam, Hawaii, Iowa, Idaho, Illinois, Indiana, Kansas, Kentucky, Louisiana, Minnesota, Missouri, Mississippi, Montana, North Carolina, North Dakota, Nebraska, Nevada, Oklahoma, Puerto Rico, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, the U.S. Virgin Islands and Wisconsin.

The list applies to areas with a positive test rate higher than 10 per 100,000 residents over a one-week rolling average or areas with a 10% or higher positivity rate over a one-week rolling average.

New York was the U.S. epicenter of the pandemic in March and April, but of those tested across New York state on Monday, less than 1% were positive, Cuomo said.

New York currently has 109 coronavirus patients in ICUs — the lowest number since March 15.

Sep 01, 10:49 am
Start of in-person school delayed in NYC

The start of in-person learning in New York City public schools has been delayed to Sept. 21, Mayor Bill de Blasio announced Tuesday.

The district’s blended-learning plan was scheduled to begin on Sept. 10.

“Teachers who usually get two days of professional development at the beginning of the school year will now get nine,” schools Chancellor Richard Carranza said. “We’ve heard from everyone in our schools that have said we need some more time.”

In averting a strike authorization vote by the United Federation of Teachers later Tuesday, de Blasio agreed to delay the start of school to Sept. 16 for all-remote instruction. In-person learning, which is limited to a few days per week, will begin Sept. 21.

The mayor also announced expanded testing for teachers, a significant concession to the United Federation of Teachers.

ABC News’ Aaron Katersky contributed to this report.

Sep 01, 9:27 am
White House reinstating public tours

White House public tours will resume on Sept. 12, though the number of visitors will be limited to 18% of the usual capacity, according to a Tuesday statement from the first lady’s office.

Tours will also be cut down to two days per week instead of five days per week.

Everyone ages 2 and older must wear a face covering and practice social distancing.

Sep 01, 9:11 am
Bureau of Prisons resumes in-person visits

The Bureau of Prisons said Monday that it’s resuming in-person visits at all 122 of its facilities, according to an internal memo obtained by ABC News.

“Social visiting will resume no later than Saturday, October 3, 2020,” the memo said, adding that visiting will be non-contact only.

“Use of Plexiglas or a similar barrier between inmate and visitors will prevent any contact. In the alternative, if a barrier is not present, social distancing (i.e., 6 feet apart) between visitors and inmates must be enforced,” the memo said.

Inmates and visitors must wear face coverings at all times.

Every inmate will be permitted two visits per month. Inmates in isolation or quarantine will not be allowed visits.

Sep 01, 8:19 am
‘We’re all on the same team,’ Fauci says of Trump

Dr. Anthony Fauci, the nation’s top medical expert on the coronavirus pandemic and a key member of the White House coronavirus task force, is weighing in on comments President Donald Trump made during a recent interview with Fox News.

Speaking to Fox News’ Laura Ingraham on Monday, Trump said he “inherited” Fauci, who is the director of the National Institute of Allergy and Infectious Diseases, and that he disagrees with “a lot” of what he says.

“I think when you get statements like that, that doesn’t really reflect what goes on,” Fauci told ABC News’ Amy Robach in an interview Tuesday on Good Morning America. “I think that’s kind of a distraction to pit me against the president. We’re all on the same team.”

Fauci also attempted to clarify new information released by the U.S. Centers for Disease Control and Prevention, which showed 94% of those who died from COVID-19 as of last week had underlying health conditions and contributing causes.

“The point the CDC was trying to make was that a certain percentage of them had nothing else but just COVID. That does not mean that someone who has hypertension or diabetes who dies of COVID didn’t die of COVID-19. They did,” he said. “So the numbers that you’ve been hearing, the 180,000 plus deaths, are real deaths from COVID-19.”

Trump, however, retweeted a conspiracy theory that suggested only 9,000 people have died from COVID-19 in the United States.

“Let there not be any confusion about that. It’s not 9,000 deaths from COVID-19; it’s 180,000 plus deaths,” Fauci added.

When asked about the CDC’s new guidelines on COVID-19 testing, Fauci admitted, “That did create some confusion.”

“The way that sentence was said, it gave the impression that they’re not concerned about community spread and that people who are asymptomatic should not be tested,” he said. “There’s no doubt that there are asymptomatic infection and that asymptomatic people can transmit and that you can and should test asymptomatic people.”

“What the guideline was trying to do was to try to make the point that not everyone who wants to be tested should be tested; only if you need to be tested,” he continued. “Understandably, that was confusing. Hopefully, that’s been straightened out now.”

Sep 01, 7:16 am
Arizona State University reports over 800 cases

Arizona State University said it now has 803 known cases of COVID-19 among its students and staff.

Since Aug. 1, the public research university has collected test results from 40,402 students and employees so far. As of Sunday, 775 students and 28 staff and faculty members had tested positive for COVID-19. All positive cases are in isolation, according to the school.

“It is our expectation that COVID-19 is not going away anytime soon and that we must find a way to operate the university in a way that accounts for the ongoing presence of the virus,” Arizona State University said in an update posted on its website Monday night. “The incidence of testing has increased as we launched periodic testing of a statistically significant percentage of the on-campus population. ASU maintains a low positivity rate with students and an even lower positivity rate with faculty and staff.”

Most of the cases — 428 — were among people living off campus in the metropolitan Phoenix area. Another 323 are in isolation on the Tempe campus, where a total of 9,645 students live. The remaining are in isolation on either the downtown Phoenix or West campuses, where a collective total of 1,717 students live.

The university said there are currently no known cases at the Polytechnic campus, where 757 students live.

Sep 01, 5:44 am
Russia’s case count surpasses one million

Russia has recorded 4,729 new cases of COVID-19 and 123 related deaths over the past 24 hours, the country’s coronavirus response headquarters said Tuesday morning.

The nation’s cumulative total now stands at 1,000,048 confirmed cases with 17,299 deaths.

Russia is the fourth country in the world to reach the one million mark of COVID-19 diagnoses, after the United States, Brazil and India, according to data from Johns Hopkins University.

Sep 01, 4:10 am
US case count tops six million

There were 33,888 new cases of COVID-19 identified in the United States on Monday, bringing the country’s cumulative total soaring past six million, according to a real-time count kept by Johns Hopkins University.

Monday’s tally is far below the country’s record set on July 16, when 77,255 new cases were identified in a 24-hour reporting period.

An additional 595 coronavirus-related deaths were also recorded Monday. The latest daily death toll is well under the record 2,666 new fatalities that were reported on April 17.

A total of 6,031,013 people in the United States have been diagnosed with COVID-19 since the pandemic began, and at least 183,598 of them have died, according to Johns Hopkins. The cases include people from all 50 U.S. states, Washington, D.C. and other U.S. territories as well as repatriated citizens.

By May 20, all U.S. states had begun lifting stay-at-home orders and other restrictions put in place to curb the spread of the novel coronavirus. The day-to-day increase in the country’s cases then hovered around 20,000 for a couple of weeks before shooting back up and crossing 70,000 for the first time in mid-July.

However, the numbers of new COVID-19 cases and new deaths in the United States have both decreased by substantial amounts in week-over-week comparisons, according to an internal memo from the Federal Emergency Management Agency obtained by ABC News last week.

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