5-month-old daughter of New York firefighter dies of COVID-19 The novel coronavirus has killed more than 49,700 people in the U.S.

A global pandemic of the novel coronavirus has now killed more than 190,000 people worldwide.

Over 2.7 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 the scope of their nations' outbreaks.

Since the first cases were detected in China in December, the United States has become the worst-affected nation, with more than 873,000 diagnosed cases and at least 49,748 deaths.

Today's biggest developments:

Global cases surpass 2.7 million

New York antibody tests results released

Idaho details plan to reopen state

Germany is on 'thinnest ice,' Angela Merkel warns

Here's how the news is developing today. All times Eastern. Please refresh this page for updates

6:46 p.m.: Over 10,000 nursing home residents have died

At least 10,631 nursing home residents have died of COVID-19 in the U.S., an ABC News survey of available state data has found.

New York has had the highest number of long-term care residents die from COVID-19, with 3,540.

The count is based on data provided by governors' offices and state departments for 28 states and the District of Columbia. Not all states responded to requests for this information.

A federal tally of this data is currently unavailable.

5:09 p.m.: Death toll at Holyoke Soldiers' Home up to 68

The number of veterans who have died at the Soldiers' Home in Holyoke, Massachusetts, has risen to 68 after two more deaths were reported Thursday, according to the state's Office of Health and Human Services.

Of those deaths, 57 tested positive for coronavirus, nine tested negative, one had a pending result and one was unknown, according to the agency.

The state-run health facility is the subject of two investigations -- one federal and one ordered by Gov. Charlie Baker -- on their handling of the virus' spread inside the facility.

To date, 90 veteran residents have tested positive and 60 veteran residents have tested negative. Eighty-one staff members have also tested positive.

The Office of Health and Human Services said the use of personal protective equipment is being monitored and enforced at the home, and an additional 250 face shields were donated Wednesday.

4:56 p.m.: Stay-at-home orders extended in 2 states

North Carolina Gov. Roy Cooper and Illinois Gov. J.B. Pritzker have both extended their state's stay-at-home orders. The order in North Carolina is now in effect until May 8. In Illinois, the order will remain in place until May 30.

Cooper said that while the curve is flattening, North Carolina is not yet ready to lift the restrictions, which mandated that all nonessential businesses remain closed.

There are now 7,608 confirmed cases in the state, an increase of 388 in the last 24 hours. Cooper said it was the second-highest day of reported cases.

Pritzker said that social distancing is work in Illinois, but he is asking residents to "hold on for just a little while longer." He also announced a new measure under the order, which requires anyone over the age of 2 years old to cover their faces in public spaces where social distancing is difficult.

However, some restrictions would be relaxed on May 1, when the new order begins.

Some of those changes include hospitals and surgicenters resuming some elective surgeries, retail stores that are not currently deemed essential businesses taking phone or online orders for pick-up or delivery only and reopening some state parks.

In Illinois, there are now 36,934 confirmed cases, with an increase of 1,826 new cases in the last 24 hours, according to the governor.

4:21 p.m.: 5-month-old daughter of NY firefighter dies

The infant daughter of New York firefighter Jerel La Santa has died of coronavirus, her mother and the FDNY Hispanic Society confirmed.

The girl, named Jay-Natalie La Santa, was 5 months old.

"My baby girl was so beautiful," Lindsey La Santa, her mom, told ABC News.

The department said in a statement, "Our thoughts and prayers are with the La Santa family during this tragic time."

Jerel La Santa was appointed to the title of firefighter less than a year ago, in November 2019, according to the FDNY.

New York state had only two deaths -- out of 15,740 total -- of people under 9 years old through Wednesday, according to the Department of Health.

3:59 p.m.: California reports deadliest day

California experienced its deadliest day Thursday, as the daily death rate continues to increase.

In the last 24 hours, 115 people were reported to have died in the state, marking the largest daily total, according to Gov. Gavin Newsom.

However, Thursday was also the first day that hospitalizations, ICU admissions and hospitalized persons under investigation for COVID-19 all declined, Newsom said.

The governor also urged people to continue practicing social distancing, even as a hot weekend approaches. Newsom anticipated a "significant increase" in the volume of people trying to visit the beaches and if people do not listen, he said residents should expect to hear that the hospitals numbers will go up in a week or so.

3:45 p.m.: Death toll of NYC homeless population rises

At least 51 homeless New Yorkers have died amid the pandemic as of Thursday, according to the Dept. of Social Services.

It was an increase of 11 since Monday.

There are now 653 total positive cases in the homeless population, including 570 cases among sheltered people, 25 among unsheltered and 58 agency referrals, according to the department.

The number of positive cases includes the deaths.

There was an increase of those discharged from isolation. As of Thursday, 469 homeless New Yorkers had been discharged, the department reported. Those discharged included people whose conditions have either abated or resolved, as well as people who exhibited mild illness and completed isolation following the city's guidance.

2:13 p.m.: South Korea health agency says virus may not live in people who were re-diagnosed

The Korean Centers for Disease Control and Prevention announced that in 25 randomly selected patients, all had developed antibodies that had defensive power.

Those 25 patients in South Korea were hospitalized with symptoms at the time of the antibody testing and have now fully recovered, according to the agency.

Initially, there was concern about the effectiveness of the antibody in killing the virus because 12 of the 25 had both the virus and the antibodies. However, after attempts were made to grow the virus, it did not replicate, suggesting that the virus detected in the body may have not been live or was just viral remnants and therefore did not have the ability to infect others, according to KCDC.

In a separate study of 207 people who had been re-diagnosed with the virus, the agency confirmed that the virus had not grown in their bodies either. KCDC said it had attempted to grow the virus twice.

2:08 p.m.: Saliva-based testing to start in New Jersey development centers

Saliva-based testing will begin for residents and staff at New Jersey's five developmental centers next week, Gov. Phil Murphy announced Thursday.

The testing was developed by Rutgers University and will bring a total of more than 5,500 tests to the centers, Murphy wrote on Twitter.

"These are among our most vulnerable residents and our most essential workers," the governor said. "We owe our residents and staff our best, and testing will help us best serve them."

The state's Department of Health Services describes residents in the development centers as people with "intensive needs related to their developmental disabilities, and many also have co-occurring mental health, behavioral health and/or medical needs."

Murphy also announced in his daily briefing that there were 4,247 new cases reported, putting the total number of confirmed cases in the state at 99,989. Deaths amounted to 5,368, after an additional 307, according to the governor.

He noted that while the curve is flat, people should not expect to be packed together anytime soon.

1:30 p.m.: Idaho governor announces plan to reopen state

Idaho Gov. Brad Little announced his plan to reopen the state with a four-stage solution.

The outline of the plan was detailed online.

In the first stage, which begins on May 1, some nonessential businesses, including retail stores and day cares, may reopen. However, bars, restaurants, gyms, hair salons and large venues, like move theaters and sporting venues, will remain closed. Gatherings are still discouraged and should be avoided. Visitors will also have to enter a 14-day quarantine when entering the state.

The second stage allows for gatherings of less than 10 to occur and restaurants can reopen for in-person dining when a distance plan has been approved by the health department. Gyms and hair salons can also reopen, but large venues and bars will have to stay closed. The 14-day quarantine for visitors still applies. The second stage has a target date of May 16, but it will be reevaluated.

The third stage, set to begin on May 30, loosens the gathering restrictions and allows for up to 50 people to gather at once. Bars and large venues remain closed, but both will be required to work on reopening plans for limited occupancy. Nonessential travel can also resume to places where an ongoing transmission is not happening.

The fourth and final stage, with a targeted beginning date of June 13, allows for vulnerable Idahoans to resume public interactions while practicing physical distancing. Gatherings of more than 50 are also allowed to take place, but only with "appropriate physical distancing and precautionary measures." Similarly, bars and large venues can reopen but must operate with limited occupancy and proper distancing. This stage also permits onsite working to take place with physical distancing.

12:10 p.m.: Cuomo releases results from NY antibody tests

About 13.9% of the 3,000 New Yorkers who were part of randomized antibody tests in the state were infected and developed an antibody, according to Gov. Andrew Cuomo.

Cuomo announced the data at his daily press briefing, but noted it is preliminary. The data was collected over two days in 19 counties and 40 localities across New York from people who were out in public.

Of the 13.9%, the data showed that more men tested positive, despite making up a smaller portion of the study.

The data also gave some insight into the regions where infection is spreading: New York City has the highest rate of positive antibody results, with residents accounting for 43% of the study and making up 21.2% of the positive tests. Long Island accounted for 14.4% of the study and made up 16.7% of the positive tests, while Westchester and Rockland Counties accounted for 9.8% of the study and made up 11.7% of the positive tests. The rest of the state accounted for 32.8% of the study and made up 3.6% of the positive tests.

In terms of a racial breakdown, white people were the largest group tested in the study, at 57.1%, but had the lowest positive results at 9.1%. The groups that had the three highest positive tests were multi/none/other (22.8%), Hispanic and Latino (22.5%), and black people (22.1%). Asian people had a positive test percentage of 11.7%.

Cuomo, extrapolating the data, said it’s likely 2.7 million people in the state have been infected, with a death rate of 0.5%.

He also said the current death toll of 15,302 is not accurate because it does not include people who died at home and those who were never tested for COVID-19.

Cuomo added that more testing needed to be done among the African American and Hispanic community.

More testing and surveys will continue in the state, Cuomo said, with plans to expand the size.

11:29 a.m.: China pledges $30 million donation to WHO funding

China has pledged to donate $30 million in funding to the World Health Organization (WHO) to support the agency's effort to fight the pandemic, the state-run Xinhua reported.

Foreign Ministry spokesperson Geng Shuang backed the WHO's handling of the pandemic, saying at a briefing that it played an important role in assisting countries in responding to the outbreak and boosting international cooperation.

The pledged donation comes amid criticism from President Donald Trump and his administration of the WHO.

Secretary of State Mike Pompeo said that the WHO did not enforce its rules regarding data that China shared. However, the United Nations agency does not have enforcement ability.

Trump also said he would halt all funding to the WHO. Senior U.S. officials said Wednesday that while existing work would continue, "new funding" would be paused while a review is conducted.

Xinhua reported that in March, China donated $20 million to the WHO.

11:02 a.m.: Sen. Elizabeth Warren's eldest brother dies after testing positive

The eldest of Massachusetts Sen. Elizabeth Warren's three older brothers, Don Reed, died Tuesday night, three weeks after testing positive for COVID-19. He was 86.

Warren confirmed the news in a statement and tweet.

"I’m grateful to the nurses and frontline staff who took care of him, but it’s hard to know that there was no family to hold his hand or to say 'I love you' one more time—and no funeral for those of us who loved him to hold each other close. I'll miss you dearly my brother," she tweeted, in part.

Warren, a former Democratic presidential contender, spoke proudly of her brothers on the campaign trail.

Reed was a U.S. Air Force veteran and one of her two Republican brothers. Though he and his siblings only appeared once on the trail with her when she was in Oklahoma, they never spoke to the press. They did appear in a campaign video for their little sister.

Warren had not previously mentioned her brother's diagnosis, but she has been outspoken about the pandemic's grip on the world.

10:32 a.m.: Around 1 million New Yorkers could have been exposed to COVID: Health commissioner

Despite what appears to be slow progress in New York City, the mayor and health commissioner gave a sobering look at how many New Yorkers most likely have been and will continue to be affected by the pandemic.

Health Commissioner Oxiris Barbot said that she would not be surprised if "close to a million New Yorkers" had been exposed to COVID-19. In the city of about 8.3 million, there have been at least 138,000 confirmed cases, Barbot said Thursday during Mayor Bill de Blasio's daily press briefing.

De Blasio also offered a stark statistic: he expects that an additional one million residents could become food insecure under the pandemic, putting the total number of food insecure New Yorkers at around two million.

He said that by the end of April, the city is expected to have served out about 10 million meals. For May, de Blasio said that number could rise to 15 million.

De Blasio offered hope to New Yorkers, saying he believes the city will persevere, but also warned that "we're still very much in this fight."

The number of people admitted to New York City hospitals with suspected COVID-19 cases was down again, from 252 to 227, according to the mayor. The number of people in ICUs was also down, but de Blasio noted that 796 people admitted to ICUs was still "way too many people."

He said the city is on track to conduct 20,000 to 30,000 tests per day in May. De Blasio continued to say that testing is the key to reopening the city and keeping New Yorkers safe.

7:02 a.m.: All frontline workers in Los Angeles can now get tested for COVID-19

The city of Los Angeles is expanding its criteria for who is eligible to get free testing for the novel coronavirus.

Starting Thursday, all of the city's frontline workers can get tested for COVID-19 whether they have symptoms or not.

Los Angeles Mayor Eric Garcetti, who made the announcement at a press briefing Wednesday night, said the frontline workers include health care professionals, first responders, grocery store workers and critical government personnel.

"We wish we could open that up to everybody, but I think we all know that we have firefighters and police officers, doctors, nurses, janitors at hospitals, folks that are in grocery stores and pharmacies that are putting themselves out on the line," Garcetti said. "And we want to make sure they are healthy, that they have the peace of mind knowing they’re healthy, and because they interact with so many people, that we can make sure they are not spreading it."

The city's public testing sites have the capacity to test 12,200 people per day, according to Garcetti.

Tune into ABC at 1 p.m. ET and ABC News Live at 4 p.m. ET every weekday for special coverage of the novel coronavirus with the full ABC News team, including the latest news, context and analysis.

6:25 a.m.: France wants all retailers to reopen next month

The French government wants all shops -- except bars, cafes and restaurants -- to be able to reopen once a nationwide lockdown ends next month.

"We want all retailers to be able to open on May 11 in the same way out of fairness," French Finance Minister Bruno Le Maire told France Info radio on Thursday. "I would only set aside restaurants, bars and cafes that will need special treatment because they are a place of mixing."

Le Maire noted that protocols would have to be implemented to protect both workers and customers. It's still unclear whether the reopening would be feasible nationwide or only by region, he said.

French President Emmanuel Macron announced last week that the country's lockdown, which was put in place on March 17 to curb the spread of the novel coronavirus, will be extended until May 11 and gradually lifted thereon.

France has recorded more than 157,000 diagnosed cases of COVID-19 and over 21,000 deaths, according to a count kept by Johns Hopkins University.

What to know about coronavirus:

How it started and how to protect yourself: Coronavirus explained

What to do if you have symptoms: Coronavirus symptoms

Tracking the spread in the U.S. and worldwide: Coronavirus map

5:12 a.m.: Germany is on 'thinnest ice,' Angela Merkel warns

German Chancellor Angela Merkel warned that her country is "still at the beginning" of the coronavirus pandemic and citizens must maintain discipline.

"We are still far from out of the woods," Merkel said while addressing the German parliament Thursday.

More than 150,000 people in Germany have been diagnosed with COVID-19, and 5,315 of them have died from the disease so far, according to a count kept by Johns Hopkins University. It's a relatively low death toll compared to other European countries like France and Italy that have similar caseloads but fatalities have soared past 20,000.

Germany's federal and state governments recently agreed to relax some of the social distancing measures put in place to combat the outbreak, including permitting smaller shops to reopen this week.

"It is precisely because the figures give rise to hope that I feel obliged to say that this interim result is fragile," Merkel said. "We are on thin ice, the thinnest ice even."

3:30 a.m.: American Red Cross will soon use antibody tests to ID plasma donors

Starting next week, the American Red Cross will offer antibody tests for people who suspect they were previously infected with the novel coronavirus and are interested in donating their blood plasma -- a potential game-changer in the treatment for seriously ill COVID-19 patients.

"That completely changes the landscape," Dr. Pampee Young, chief medical officer for the American Red Cross, told ABC News in an interview Wednesday.

Antibody tests can indicate whether a person has been exposed to the novel coronavirus and has recovered, developing the antibodies to fight it. And while there is no guarantee that antibodies to this new virus actually provide immunity, doctors are hopeful that patients severely sickened with COVID-19 can benefit from infusions of blood plasma collected from those who have recovered from the disease. The therapy, known as convalescent plasma, is a century-old technique used for treating epidemics.

At the moment, an individual who wishes to donate blood plasma for the experimental convalescent plasma therapy must have documentation of a positive COVID-19 test. The lack of diagnostic tests available has led hospitals and donation centers to say they are in desperate need of donors.

"Qualifying and getting the right donors into our centers to donate is one of the biggest hurdles in this in this endeavor," Young said.

More than 30,000 people have requested to donate on the American Red Cross website, but only 2 to 3% actually qualify and meet the current criteria set by the U.S. Food and Drug Administration. That donor pool could increase dramatically with the implementation of antibody testing at American Red Cross donation centers.

"All of those (potential) donors who don't have confirmed testing can now be tested," Young said. "We can really cut through that time, which is so important."

Young explained that researchers and medical professionals have been in uncharted territory, "building the plane as you’re flying it." But she said they’ve been working around the clock to streamline the process.

"We really didn't know what we were dealing with at the beginning as we were standing this up," she told ABC News. "Now we’ve really resourced this project.”

ABC News' Ibtissem Guenfoud, Jenna Harrison, Kaylee Hartung, Marilyn Heck, Sasha Pezenik, Cheyenne Haslett, Conor Finnegan, Aaron Katersky, Matthew Fuhrman, Dr. Abdelmalek, Joohee Cho and Fergal Gallagher contributed to this report.