The coverage on this live blog has concluded.

The United States is administering about 2.5 million Covid-19 vaccine shots every day. However, the number of new cases is increasing in 21 states as highly infectious variants spread and governors relax restrictions on businesses. Gov. Andrew Cuomo on Saturday confirmed that a more contagious Covid variant originally identified in Brazil has been detected in New York.

Here are some of the biggest developments Monday:

• Europe looks to new lockdowns amid vaccine troubles and a third wave
• WHO says most regions of the world are seeing an increase in cases
• AstraZeneca vaccine found to be 79% effective in U.S. trial
• Microsoft is letting employees come back to headquarters
• CDC warns drop in hospitalizations is stalling

The U.S. is recording at least 54,300 new Covid-19 cases and at least 1,000 virus-related deaths each day, based on a seven-day average calculated by CNBC using Johns Hopkins University data.

The following data was compiled by Johns Hopkins University:

• Global cases: More than 123.53 million  
• Global deaths: At least 2.72 million
• U.S. cases: More than 29.85 million
• U.S. deaths: At least 542,818

Travel industry to Biden: Make a plan on how to lift travel restrictions by May 1

More than two-dozen travel-industry groups are urging the Biden administration to lift international travel restrictions for vaccinated individuals and other measures to revive demand for trips.

Airlines for America — which represents most large U.S. carriers, as well as the largest flight attendant union, hotel and airport associations and the U.S. Chamber of Commerce — called on the White House to come up with a "roadmap" by May 1 toward rescinding travel bans that have devastated international air travel between the U.S. and Europe.

They also asked the Biden administration to set standards for digital health passports that could be used to show officials vaccine status or test results.

The Centers for Disease Control and Prevention reiterated earlier on Monday its recommendation against traveling now, but the travel groups are also asking the CDC to change its guidance.

—Leslie Josephs

Brazilian economists call for tougher measures as Covid cases in Brazil rise

Nearly 200 economists in Brazil urged the country's government to impose tougher restrictions and speed up Covid vaccinations as coronavirus cases continue to rise, the Associated Press reports.

"This recession, as well as its harmful social consequences, was caused by the pandemic and will not be overcome until the pandemic is controlled through competent action from the federal government," the economists said Monday in a letter. "It is urgent that the different levels of government prepare to implement an emergency lockdown."

Brazil's economy contracted by 4.1% in 2020, its biggest annual recession in decades, the AP said. Brazil is also the country with the second-most Covid-19 cases confirmed with more than 11.99 million, according to data from Johns Hopkins University. There have also been at least 294,042 Covid-related deaths in Brazil, the second-most of any country.

—Fred Imbert

White House reportedly considering splitting $3 trillion over two bills to remedy infrastructure, inequality

The White House is reportedly considering splitting an estimated $3 trillion in economic recovery funds into one inequality bill and one infrastructure bill.

The New York Times first reported that President Joe Biden's advisors will present him with two pieces of legislation: One would inject money into manufacturing, improving transportation systems and expanding broadband and reducing carbon emissions.

The other would focus on reducing economic inequities through investments in paid leave, universal pre-K and community college, the report said.

— Jacob Pramuk, Thomas Franck

Biden administration could lift press limits at border this week amid migrant surge

The Biden administration could increase press access along the U.S.-Mexico border as soon as this week, House Homeland Security Chairman Bennie Thompson, D-Miss., said Monday.

"I am certain, before the week's out, press will have access" at the border, Thompson said on MSNBC. "If not, it will be a problem."

White House press secretary Jen Psaki, pressed Monday on when reporters will be able to tour border facilities, hinted that changes were forthcoming: "We are working to finalize details, and I hope to have an update in the coming days."

The White House has come under intense criticism for limiting transparency amid a surge in migrant arrivals, including a record number of unaccompanied migrant children. As of Sunday, nearly 16,000 migrant children were in U.S. custody, NBC News reported. The surge in migrant arrivals comes as the U.S. races to inoculate its residents from the coronavirus. Covid cases are also on the rise in 27 states, according to data compiled by Johns Hopkins University.

Homeland Security Secretary Alejandro Mayorkas said that the coronavirus has complicated border operations.

—Kevin Breuninger

WHO says most regions of the world are seeing an increase in cases

Most regions of the world are seeing an increase in new Covid-19 cases as highly contagious variants spread, a top World Health Organization official said.

New cases worldwide increased by 8% over the last week, the fifth week in a row that the WHO has seen an increase in transmission, according to Dr. Maria Van Kerkhove, the agency's technical lead for Covid-19.

Cases in Europe increased by 12%, Kerkhove said. The WHO has also seen a 49% increase in cases in Southeast Asia, an 8% increase in the Eastern Mediterranean and a 29% increase in the Western Pacific region. she said. The Americas and Africa saw a "slight decline," Kerkhove said, but added that the case numbers overall are "worrying."

"There is still far more we can do at an individual level, at a community level, as leaders in government, she said, urging the public to continue to practice Covid safety measures.

–Berkeley Lovelace Jr.

CDC needs to update Covid guidelines quicker to reflect new science, Gottlieb says

Dr. Scott Gottlieb told CNBC the Centers for Disease Control and Prevention needs to revise its coronavirus guidelines more quickly when new data and evidence emerges.

Early on, public health officials based recommendations under the assumption the coronavirus spread like the seasonal flu, according to Gottlieb, calling it "reasonable" decision given the lack of information available.

However, he said on "Squawk Box," that "it has not behaved like flu," leading to both overestimations and underestimations of the virus.

"It isn't so much a question of: Were we wrong about that? We were wrong in certain respects. But: Did we learn quickly enough and did we adapt our recommendations and guidelines quickly enough? And the answer is no," the former U.S. Food and Drug Administration commissioner said.

— Kevin Stankiewicz

Dr. Scott Gottlieb is a CNBC contributor and a member of the boards of Pfizer, genetic testing start-up Tempus, health-care tech company Aetion and biotech company Illumina. He also serves as co-chair of Norwegian Cruise Line Holdings′ and Royal Caribbean's "Healthy Sail Panel.

Arizona and Wisconsin expand vaccine eligibility

Arizona is expanding its vaccine eligibility this week, announcing that anyone aged 16 and older can make an appointment to receive the Covid-19 vaccine beginning March 24.

Wisconsin made a similar announcement, saying residents aged 16 and older with certain medical conditions can make an appointment to receive a vaccine, effective immediately.

So far, Arizona has administered almost 3 million Covid-19 vaccine doses, and Wisconsin has administered just over 2 million, according to state numbers.

–Rich Mendez

Lack of vaccines for seafarers could leave global shipping vulnerable

The International Chamber of Shipping is warning that global supply chains are at risk if seafarers don't have access to vaccines, according to a legal document seen by CNBC expected to be published this week, CNBC's Lori Ann LaRocco reports.

In the document, the ICS says that countries are requiring all crew member be vaccinated before allowing entry into their ports.

Currently, there are 200,000 seafarers stuck either at home or at sea waiting for a crew change. Vaccination requirements could also cause voyages to be canceled, putting the global supply chain at risk.

"You can have 30 different nationalities on board a vessel at any one time," explained Guy Platten, secretary general of the International Chamber of Shipping. "Half of shipping's workforce resides in nations that will not have access to a vaccine for two or three years."

The ICS is in communication with countries around the world to figure out solutions such as vaccine hubs in key international ports.

–Rich Mendez

Second wave of $1,400 stimulus checks scheduled for this week

If you still haven't received your $1,400 stimulus check, there could be reason to cheer.

The government is deploying a second batch of those payments this week.

Direct deposits are slated to be available in accounts by Wednesday, March 24.

A "large number" of those checks will also be sent by mail via paper check or pre-paid debit card.

"Since this new set of payments will include more mailed payments, we urge people to carefully watch their mail for a check or debit card in the coming weeks," IRS Commissioner Chuck Rettig said in a statement.

—Lorie Konish

New York opens vaccine eligibility to people 50 and older beginning Tuesday

New York will allow residents aged 50 and older to get vaccinated against Covid-19 beginning Tuesday, Gov. Andrew Cuomo announced.

"The production is ramping up. We've spent so many months not having enough. Over the next few weeks, you're going to see the production of the vaccine ramp up," Cuomo said at a media appearance for the launch of New York's "Roll Up Your Sleeve" campaign, its latest push to equitably vaccinate residents.

According to a statement from the governor's office, just over 26% of New Yorkers have now received at least one vaccine dose.

—Noah Higgins-Dunn

Miami Beach businesses coping with curfews, crowds

Spring break is in full swing in Miami.

Some Miami Beach businesses told CNBC they are worried about the impact of curfews city officials implemented after days of maskless crowding and some unruly behavior in the popular tourist spot.

The curfews came as the number of travelers nationwide rose to the highest in more than a year — more than 1 million a day for the past 11 days, according to the Transportation Security Administration.

The Centers for Disease Control and Prevention on Monday reiterated its guidance to avoid travel, fretting that unvaccinated spring breakers and other travelers could spread catch and spread Covid-19.

—Leslie Josephs

CDC warns drop in hospitalizations is stalling

New cases of Covid-19 are once again on the rise across more than half of the United States and the recent drop in hospitalizations is slowing, Centers for Disease Control and Prevention Director Dr. Rochelle Walensky warned Monday.

As of Sunday, the seven-day average of new cases rose by 5% or more in 27 states, according to a CNBC analysis of data compiled by Johns Hopkins University.

The rise in cases comes after weeks of declining numbers and as the U.S. makes strides in vaccinating large parts of the population. But even as vaccinations increase, the threat of more contagious and potentially more deadly variants looms.

"Like Covid-19 cases, hospital admissions have been relatively stable over the last two weeks, hovering around 4,500 to 5,000 admissions per day," Walensky said Monday. She added that "we are at a critical point in this pandemic, a fork in the road."

—Will Feuer

Krispy Kreme giving out free doughnuts to anyone who's vaccinated

Krispy Kreme said it will offer a free "Original Glazed" doughnut to anyone who provides proof of having been vaccinated, the company said in a release.

You must show your Covid-19 vaccination record card to get one free donut. No purchase is necessary and the offer is redeemable once a day from Monday until December 31, 2021, at participating locations.

–Rich Mendez

Amazon workers go on strike in Italy over working conditions amid the pandemic

Amazon warehouse and delivery employees in Italy have gone on a 24-hour strike to draw attention to concerns around working conditions.

Workers and trade unions calling for changes to shifts, workloads and benefits. Trade unions FILT-CGIL, FIT-CISL and Uiltrasporti said they called the strike after negotiations broke down with Assoespressi, an employer association representing last-mile and e-commerce couriers, including some of Amazon's third-party delivery firms in Italy.

Workers also highlighted the need for pay increases as Amazon warehouses continued to operate throughout the coronavirus pandemic, which saw an unprecedented surge in e-commerce activity. Amazon was one of the biggest beneficiaries of this surge, supplying both essential and non-essential goods to stuck-at-home shoppers.

An Amazon spokesperson told CNBC the company and its delivery partners "already offer what these groups are asking for."

— Annie Palmer

Microsoft is letting employees come back to headquarters

Microsoft said that starting March 29 more employees can return to its Washington headquarters.

The company will allow employees who work at its Redmond, Wash., sites and nearby campuses to choose between returning to work full-time, continuing to work remotely or implementing a hybrid model.

"We've been closely monitoring local health data for months and have determined that the campus can safely accommodate more employees on-site while staying aligned to Washington state capacity limits," the company said.

Following several months of office closures due to the coronavirus pandemic, employers are beginning to permanently shift to more hybrid work models or planning to forgo traditional office spaces entirely.

Microsoft told employees last October it will allow more flexibility to work from home, even after it's safe to return to the office. The company said it planned to allow employees to work remotely less than 50% of the time. Employees can also request approval from their managers to work remotely full time or to potentially move to a new location.

—Jessica Bursztynsky

New Jersey likely to pause reopening plans as cases rise, governor says

New Jersey will likely pause its reopening plans as Covid-19 cases begin to rise again in the state, Gov. Phil Murphy said.

New Jersey has opened up its indoor capacity of restaurants and other businesses to 50%, but the state leads the U.S. in new Covid cases per capita over the past week, according to data from the Centers for Disease Control and Prevention.

"My guess is, we won't be opening up further capacity for some time now because of .. the caseload," he said, adding that he thinks things should improve as the weather gets warmer and more people in the state get vaccinated.

Other states are also seeing a rise in new cases as they reopen, and health officials are concerned that could cause a new surge as highly contagious variants spread across the nation.

—Berkeley Lovelace Jr.

UK and EU vaccine spat deepens as Brussels works on new export controls

The European Union is considering restricting exports of Covid-19 vaccines across to the U.K. and the 27-member region is increasingly frustrated at AstraZeneca.

The firm has not respected its delivery targets to the bloc on different occasions, having reduced the number of shots delivered to the EU twice in the first quarter and once for deliveries in the second quarter.

On the other hand, AstraZeneca has met its delivery targets for the U.K. — where the vaccination rate is higher than in the EU — even though some of these vaccines are coming from plants in the European Union. The U.K. placed its order for the AstraZeneca shots earlier than the EU.

"The EU needs to secure deliveries of vaccines to Europeans in line with companies' contractual obligations," a spokesperson for the European Commission told CNBC.

—Silvia Amaro

Computer programmers are helping some snag elusive vaccination appointments

With competition for vaccination appointments extremely high in many areas of the U.S. — despite new vaccines becoming more readily available — families and friends are turning to computer programmers they know to help snag elusive slots, NBC News reported.

Github, a website where programmers can share their codes, hosts myriad uploaded scripts that are designed to help people secure vaccine appointments, according to NBC News. For example, some of these programs scrape official state vaccination websites or pharmacy chain sites every few seconds searching for open slots. 

While a few programmers have used these programs to create large public portals, such as the NYC Vaccine List, many are keeping limiting their searches for just family and friends, NBC News said. The reason? Some told NBC News they know that a system that makes it easier to get a vaccination slot if you know a programmer is fundamentally unfair.

—Terri Cullen

AstraZeneca U.S. president discuses vaccine trial data, plans to seek U.S. approval

Ruud Dobber, president of AstraZeneca U.S., joined CNBC's Meg Tirrell on "Squawk Box" to discuss the company's plans for seeking U.S. approval of its coronavirus vaccine developed with the University of Oxford.

—Melodie Warner 

There's some concern about latest Covid wave and lockdowns in Europe, Irish Distillers CEO says

Conor McQuaid, chairman and CEO of Irish Distillers, discusses business performance and the impact of Covid-19, EU-U.S. trade tensions, and changing consumer habits on CNBC's "Squawk Box."

AstraZeneca vaccine found to be 79% effective with no increased blood clot risk

The findings of a late-stage U.S. trial have shown that the Covid vaccine developed by AstraZeneca and the University of Oxford is 79% effective in preventing symptomatic illness and 100% effective against severe disease and hospitalization.

The data, which is based on more than 32,000 volunteers across 88 trial centers in the U.S., Peru and Chile, reaffirms that the Oxford-AstraZeneca vaccine is both safe and highly effective.

It comes shortly after several countries worldwide had temporarily suspended the use of the Oxford-AstraZeneca vaccine following reports of blood clots in some vaccinated people.

AstraZeneca said an independent data safety monitoring board found there were no safety issues regarding blood clots.

— Sam Meredith

Europe looks to new lockdowns amid vaccine troubles and a third wave of cases

More than a year after the coronavirus outbreak was declared a pandemic, Europe is struggling with a third wave of infections and ramping up of lockdown measures.

At the same time, the bloc's vaccination rollout remains sluggish amid manufacturing issues and supply snags. European Union leaders are meeting this week to once again discuss a possible ban on vaccine exports.

It comes as a handful of countries, such as France, Poland and Ukraine, implement stricter measures that are set to last several weeks at least.

A month-long partial lockdown was reintroduced in Paris Saturday, as well as in 15 other regions in France, in an effort to get on top of rising case numbers, largely attributed to new, more infectious Covid variants.

— Holly Ellyatt

Read CNBC’s previous live coverage here:

Covid updates: Gasoline demand rebounds amid reopening; Mar-a-Lago partially closes after outbreak