As the novel coronavirus surges across the U.S., with 71,000 new coronavirus cases across the country on Thursday, the most in a single day, the debate about whether state governments should be requiring masks has becoming increasingly contentious. In the past weeks, a growing number of states have begun issuing new mask requirements.

In an analysis of all 50 states, ABC News found that 28 states, Washington D.C., and Puerto Rico, have issued statewide mask mandates.

The 28 states that have issued mask mandates are Alabama, Arkansas, California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Montana, Nevada, New Jersey, New Mexico, New York, North Carolina, Oregon, Pennsylvania, Rhode Island, Texas, Virginia, Washington and West Virginia.

ABC News’ analysis only includes statewide mandates, and does not include orders at the city or county level.

In an editorial published by the Journal American Medical Association, the Centers for Disease Control and Prevention reviewed the latest scientific evidence pertaining to wearing face masks, including two case studies that proffered evidence that they help prevent infected individuals from spreading the virus to others.

“We are not defenseless against COVID-19,” CDC Director Dr. Robert R. Redfield said in a press release, calling on Americans to wear masks in an effort to prevent the spread of COVID-19. “Cloth face coverings are one of the most powerful weapons we have to slow and stop the spread of the virus — particularly when used universally within a community setting. All Americans have a responsibility to protect themselves, their families, and their communities.”

“If anyone in this nation would just take on a face covering, practice excellent hand hygiene and be smart about their distancing in crowds, we can bring this outbreak to its knees in two, four, six, eight weeks,” Redfield said on a call with reporters Wednesday.

The two case studies demonstrated the advantages of using masks. One of the cases, investigated by JAMA, showed that compliance with masking policies reduced COVID-12 transmission within a Boston hospital system. Such a finding was corroborated by the case, last month, of two Missouri hairstylists who saw 139 clients while symptomatic with COVID-19. The clients and the stylists all wore face coverings. The investigation revealed that none of the clients, or any of their secondary contacts, developed the virus.

However, the issue has become increasingly politicized, particularly with President Donald Trump insisting that it should be voluntary and not mandated. So far, the president has publicly worn a mask only once, when visiting the Walter Reed National Military Medical Center last Saturday.

In Georgia, despite reporting a record number of current hospitalizations this week, and over 2,000 new coronavirus cases every day for four consecutive days, Gov. Brian Kemp refused to mandate the wearing of masks, urging instead for residents to voluntarily wear a mask for four weeks.

“While we all agree that wearing a mask is effective, I’m confident that Georgians don’t need a mandate to do the right thing. I know that Georgians can rise to this challenge and they will,” Kemp said in a news conference.

Kemp issued an executive order overruling local regulations that require masks in public and filed a suit on Thursday seeking to block the Atlanta City Council and Mayor Keisha Lance Bottoms from requiring face masks, depicting such orders as “unenforceable.”

“This lawsuit is on behalf of the Atlanta business owners and their hardworking employees who are struggling to survive during these difficult times,” Kemp tweeted. “I refuse to sit back and watch as disastrous policies threaten the lives and livelihoods of our citizens.”

Similarly, in Oklahoma, a state also with surging infections and rates of COVID-19-related hospitalizations, Gov. Kevin Stitt, despite testing positive for the virus himself, remained steadfast in his opposition to implementing a mask mandate.

However, an increasing number of Republican-led states, such as Texas and Arkansas, are now mandating masks, after the governors publicly opposed taking such measures in the past.

Nearly two-thirds of Americans, and an increasing number of Republicans, now say they’re wearing face masks when they leave the house, according to an Axios-Ipsos poll.

A growing number of major retailers, such as Walmart, CVS, Target, Kohl’s and Starbucks, among others, are also now requiring face coverings when entering their stores.