By JON HAWORTH, IVAN PEREIRA and MEREDITH DELISO, ABC News

(NEW YORK) — The novel coronavirus pandemic has now killed more than 600,000 people worldwide.

Over 14.5 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 actual numbers are believed to be much higher due to testing shortages, many unreported cases and suspicions that some governments are hiding or downplaying the scope of their nations’ outbreaks.

The United States has become the worst-affected country, with more than 3.8 million diagnosed cases and at least 140,957 deaths.

Here is how the news developed on Monday. All times Eastern:

10:18 p.m.: NIH head says up to three vaccines could be ready by year’s end

In an interview with ABC News’ Bob Woodruff, the director of the National Institutes of Health said he was optimistic that as many as three coronavirus vaccines could prove to be effective and safe by year’s end.

When asked what was the most optimistic scenario right now based on the current progress, Dr. Francis Collins said that, with some caution, “by the end of 2020, we will have one, two or maybe three vaccines that have been proven safe and effective in these large-scale studies — for which we have collectively 100 million doses already manufactured and ready to be distributed to the highest-risk people.”

In this scenario, manufacturing would be scaled up “rapidly” in early 2021, so that by spring 2021, “we would have most Americans able to receive the immunization,” he said. “That’s my optimistic view.”

8:21 p.m.: LA County offering $20 gift cards to incentivize contact tracing

In an effort to improve contact tracing, Los Angeles County is offering a $20 gift card to those who “fully cooperate” with their interview, Public Health Director Dr. Barbara Ferrer said Monday.

Many people do not want to share personal details with contact tracers for fear of losing their job, housing or relationships, Ferrer said. So the county is now offering the incentive to those who fully participate in the interview process, which can take over an hour.

The county has also launched a new call center to connect with people who test positive for COVID-19 and is introducing a new text-based system to check in with them, Ferrer said.

On Monday, LA County’s health department reported 3,160 new cases of COVID-19, for a total of 159,045.

4:08 p.m.: California ICU space running low as cases rise

California Gov. Gavin Newsom is continuing to urge residents to social distance and wear face coverings as the number of cases in the state continues to climb and tax hospitals.

The state recorded 6,846 new positive cases in the last 24 hours, bringing the total to 391,358, according to the governor. The state’s 14-day average has grown from 7,800 new daily cases on July 12 to 8,370 new daily cases on July 19, according to the state health department.

There were nine new deaths recorded in the last 24 hours, bringing the statewide total to 7,694. Newsom warned that while the number of new fatalities may be low, the seven-day average for new deaths was 91 on July 19, compared to 77 a week ago.

“We’ve seen numbers go up, they go down — the best way is to watch the numbers over a seven-day period,” he said.

Newsom also warned that hospitals across the state are seeing a 16% jump over the last two weeks in COVID-19 cases. Hospital ICU bed admissions were up 12% statewide during that same period, and for some facilities its worse, according to the governor.

San Benito County hospitals, he noted, have no ICU beds left.

The state announced that San Francisco County will be put on the California monitoring list, which requires additional closures from the baseline statewide measures such as indoor dining, indoor places of worship and indoor entertainment. More than 36 million people, roughly 91% of California’s population, lives in counties listed in the monitoring list.

“It’s our decisions, not our conditions, our decisions, that will determine our fate and future as it relates to the spread of this virus,” Newsom said.

3:12 p.m.: Ohio records over 1,200 new cases in 24 hours

Ohio saw 1,236 new COVID-19 cases in the last 24 hours, according to the state’s Health Department.

The state now has 76,168 coronavirus cases in total and a 21-day average of 1,196 new cases a day, according to Health Department data. Ohio recorded 15 deaths in the last 24 hours, bringing the total casualty numbers to 3,189, the health department said. The 21-day average for daily reported deaths is 18, according to the Health Department.

There is a mask mandate for 19 counties; however, Gov. Mike DeWine told “Meet the Press” on Sunday he is mulling expanding the order to more counties.

1:42 p.m.: Heat wave forces Washington, D.C. to freeze public testing sites

The heatwave hitting the East Coast has forced Washington, D.C. to suspend its coronavirus testing Monday.

The city’s Homeland Security and Emergency Management Agency sent an alert to residents that it would close all of its public testing sites because of the extreme weather. The National Weather Service said the temperature would top out at 99 degrees with a heat index above 100 in the city.

“Residents are encouraged to call their health care providers if they are in need of a test,” the alert said.

1:26 p.m.: Smithsonian to open 2 of its facilities

The Smithsonian announced it will begin the phased reopening of its Washington, D.C. cultural institutions on Friday.

The National Zoo in northwest Washington, D.C. and the National Air and Space Museum’s Steven F. Udvar-Hazy Center in Chantilly, Virginia, will be open to visitors through a timed entry pass system. Visitors above 6 years old will be required to wear face coverings and adhere to social distancing guidelines in both locations, according to the Smithsonian.

The Smithsonian will release 5,000 timed passes per day for the Zoo and about 1,500 passes per day for the Udvar-Hazy Center.

12:45 p.m.: California puts pause on high school sports

The California Interscholastic Federation, which oversees the state’s high school sports, announced it will put a pause on the beginning of the athletic season.

“It is anticipated that most Section start dates will commence in December 2020 or January 2021,” the federation said in a statement.

California has seen a jump in cases over the last few weeks and currently has 384,692 total cases, according to the state’s Health Department.

12:00 p.m.: WHO says vaccine update is promising

The emergencies chief for the World Health Organization told reporters in Geneva that the latest findings from vaccine studies are good news, but warned that there is still work to be done.

Dr. Mike Ryan said the phase one results from a vaccine study at Oxford University were promising as it showed little to no adverse effects of the vaccine. He said that more research is needed with a larger sample scale.

“We now need to move into larger scale real world trials, but it is good to see more data and more products moving into this very important phase of vaccine discovery,” he said.

11:36 a.m.: Mississippi governor extends mask mandate for more counties

Mississippi Gov. Tate Reeves told “Good Morning America” he will extend his current order for mandated masks to more counties, but will not yet issue a statewide order.

Reeves said there are over 41,000 confirmed cases in the state and health officials are recording 1,000 new cases a day. He urged residents to take the pandemic seriously and abide by the social distancing and mask guidelines.

“We think that we’ve got to make sure that everyone understands that we need your participation to help us slow the spread of this virus,” he told “GMA.”

The governor’s original mask mandate for 13 Mississippi counties was set to expire Monday, however he said he was extending the order for those areas and was adding 10 more counties to the order.

Reeves said that he was not yet considering a statewide order even though the governors in neighboring states Texas and Alabama have done so.

“I believe this is the best strategy for Mississippi,” he said.

11:13 a.m.: Florida hospitals running out of ICU beds as cases soar over 360,000

Florida health officials say their hospitals are reaching capacity in their ICUs as the number of COVID-19 cases continues to climb, with the statewide total now over 360,000.

Roughly 18% of the state’s adult ICU beds are available and 53 medical facilities in the state have maxed out their ICU bed load, according to Florida’s Agency for Healthcare Administration.

There were 292 people were hospitalized in the last 24 hours, the Florida Health Department reported Monday morning, bringing the state’s total COVID-19 hospitalizations to 21,263. There are currently 9,397 active coronavirus hospitalizations, according to the health department.

The state recorded 10,347 new coronavirus cases in the last 24 hours, bringing Florida’s total to 360,394, the Health Department said. The seven-day average of new cases has been over 10,000 for the last week, according to Health Department data.

There were 92 additional deaths recorded during that timeframe, bringing the state’s total casualty count to 5,183, according to the Health Department.

10:25 a.m.: New York officials warn of potential reclosing after crowds spotted outside restaurants

Gov. Andrew Cuomo and Mayor Bill de Blasio gave harsh warnings to New Yorkers following several reports and viral videos over the weekend that showed crowds outside New York City bars and restaurants.

A frustrated governor called the incidents “stupid” and raised concerns that those actions could increase the spread of the virus and undo the work that was done to keep case numbers down.

“We cannot allow these congregations to continue,” Cuomo said at a news conference on Monday. “We’re going to have to roll back the reopening plan and close back bars and restaurants.”

De Blasio said during his daily briefing that he shut down a restaurant in Astoria, Queens, where some customers were seen loitering in the streets. He said police officials will be out near hots pots to enforce the city’s COVID-19 rules and they are ready to shut down more establishments that don’t comply.

“It’s not widespread, but where it’s happening it will be stopped,” he said.

New York City entered phase four of the state’s reopening plan Monday, with several industries being allowed to resume operations including indoor and outdoor film productions.

The number of COVID-19 hospitalizations across the state was 716, the lowest number since March 18, and there were eight related fatalities in New York, according to the governor. Cuomo said the state will have a challenge due to the increasing number of cases throughout the country and urged New Yorkers to remain cautious.

“We have to protect the progress we made. … “An outbreak anywhere is an outbreak everywhere.”

10:13 a.m.: Oxford study on coronavirus vaccine generates promising early results

A team of scientists at the University of Oxford released promising results showing their COVID-19 vaccine appears safe in a Phase 1/2 study.

The results, which were published Monday in the scientific journal The Lancet, found the vaccine appeared to activate several parts of the immune system. Experts say only the results of an ongoing larger Phase 3 study will show if the vaccine works to protect people from the virus.

8:25 a.m.: Surgeon General pleads with Americans to wear face masks

During an interview on “Fox and Friends,” Surgeon General Jerome Adams pleaded with Americans to wear face masks and cited their benefits, despite previous vocal doubts from President Donald Trump.

Adams told the hosts Trump and the administration are on the same page and the most effective way to reopen the country safely was for every person to wear a mask voluntarily.

“I’m pleading with your viewers, I’m begging you, please understand that we are not trying to take away your freedoms when we say wear a face covering,” he said. “We are saying if we do these things, we can actually open and stay open.”

On Sunday, during his interview with Fox News’ Chris Wallace, Trump said he’s a believer masks but also “masks cause problems too,” and said there would be no national mandate for masks. He also took issue with CDC Director Robert Redfield’s statement that if everyone wore face masks over the next four to six weeks, “we could drive this epidemic to the ground.”

“I don’t agree with the statement that if everybody wear a mask everything disappears,” Trump said during the interview.

Trump also criticized Adams during the interview for earlier statements against mask use. The surgeon general admitted he and his team were wrong during the beginning of the pandemic.

“Once we realized that the science was different for this virus, we changed our recommendations,” Adams said.

Adams argued against a federal mask mandate, citing concerns over enforcement.

“I would rather help people understand why they should cooperate with wearing a mask and how they benefit from it versus simply saying we are going to force you to do it particularly sending in federal troops and using federal mechanism,” he said.

3:55 a.m.: France makes wearing mask indoors mandatory

France is taking a new step in the fight against the spread of the coronavirus, making the wearing of the mask mandatory in closed public spaces starting Monday.

Minister of Health Olivier Véran said on Saturday that the obligation to wear a mask would apply in shops, “establishments open to the public”, “covered markets” or even banks.

Wearing a mask on the street, in parks, at sea, on hiking trails or at the beach is not included in the new legislation.

The fine for non-compliance will be 135 euros ($154 U.S.).

Meanwhile, France’s health minister said that there is an estimated “400 to 500 active clusters in France” of COVID-19.

Véran told local news outlet franceinfo on Monday morning that there were “worrisome signs of an epidemic resumption in certain territories.”

“These places of contamination are mainly located in closed places and in specific environments such as slaughterhouses” said Véran. “We are very far from the epidemic wave … there is a dynamic of circulation of the virus that worries us.”

2:10 a.m.: 85 members of shipping vessel in Alaska test positive for COVID-19

At least 85 crew members on an American Seafoods ship have tested positive for COVID-19, according to the company.

A factory trawler called The American Triumph departed Oregon on June 27 with 119 crew members on board to make their way to Alaska to fish for pollock, but two weeks after the ship departed seven members of the crew reported that they were suffering from symptoms potentially associated with COVID-19.

The seven crew members were tested in Unalaska and six out of the seven of them tested positive for the virus.

All crew members were then tested and a total of 79 more workers were found to have tested positive, bringing the total to 85 crew members out of the 119 onboard the American Triumph, according to a statement by the city.

American Seafoods spokeswoman Suzanne Lugoni said that none of the crew showed COVID-19 symptoms before boarding and that the company screened employees before the fishing expedition began.

“We are moving expeditiously to relocate our crew and get them the care they need,” said American Seafoods CEO Mikel Durham. “I want to thank the Illiuliuk Family and Health Services, the City of Unalaska Unified Command, and the public health and critical infrastructure professionals in Alaska who provided us with support and clear guidance.”

Meanwhile, Alaska had 119 new cases of COVID-19 reported on Sunday — a new record for the state.

All of the crew members will now be moved to Anchorage where they will isolate.

“Our priority is supporting our crew members and protecting the community. I am deeply grateful for the entire Alaska community for working with us to get our crew the care they need,” said Durham.

ABC News’ Ibtissem Guenfoud, Christine Theodorou, Alex Stone, Jordyn Phelps and Marilyn Heck contributed to this report.

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