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ST. LOUIS - The St. Louis area on Monday became one of the first in the United States to reinstate mask requirements amid a surge in cases and low vaccination rates.
Despite pushback from some elected officials, face coverings became mandatory Monday in indoor public places and on public transportation in St. Louis city and St. Louis County for everyone ages 5 or older — even for those who are vaccinated. Wearing masks outdoors is strongly encouraged, especially in group settings.
"For those who are vaccinated this may feel like punishment, punishment for doing the right thing," St. Louis County Executive Sam Page, a Democrat, said at a news conference Monday. "I’ve heard that and I feel that frustration. While the vaccination can protect against serious illness, it can’t protect you from being infected with COVID-19 and passing it onto someone else, someone who may be more vulnerable."
RELATED: Los Angeles County re-implementing indoor mask mandate regardless of vaccination status
The decision comes as both of Missouri’s urban areas see a big uptick in coronavirus hospitalizations that began in rural areas of the state, especially in southwestern Missouri.
Missouri ranks fourth nationally in the most new cases per capita in the past 14 days, according to data collected by Johns Hopkins University Center for Systems Science and Engineering to measure outbreak caseloads and deaths across the United States.
As medical experts express concern over COVID-19-related hospitalizations from unvaccinated Americans amid a surge in cases, cities and counties across the U.S. are reinstating mask requirements in hopes of curbing another deadly wave of the ongoing pandemic.
On July 15, Los Angeles County re-implemented a requirement for residents to wear masks while indoors — regardless of vaccination status — as the county continues to see a concerning rise in COVID-19 cases and hospitalizations from the unvaccinated.
July 15 marked the seventh consecutive day of new COVID-19 cases in Los Angeles County exceeding the 1,000 mark. The 1,537 new cases reported by the county Thursday was the highest number of new cases the county has seen since early March.
An easing of safety precautions and the large number of people who remain unvaccinated in many regions are contributing to the spread of cases around the world.
The U.S. Centers for Disease Control and Prevention has not changed its advice that fully vaccinated people can safely go without masks in most situations. But Dr. Rochelle Walensky, the agency’s director, said local decisions on mask mandates could vary depending on vaccination levels and whether there's a surge.
Though COVID-19 vaccines greatly reduce the chance of severe illness and death and remain effective against variants, some experts said wearing a mask is a reasonable precaution since it's still possible to get infected.
Masking could also help prevent the spread of the virus to children too young for vaccination and people with weak immune systems.
"Personally, I continue to wear a mask when going into public spaces outside of my household, both for my own protection and for the sake of my community," said virus researcher Angela Rasmussen of the Vaccine and Infectious Disease Organization at the University of Saskatchewan.
Dr. William Schaffner, an infectious disease expert at Vanderbilt University, said a "belt-and-suspenders" approach also makes sense for people who are older or have health issues and are more vulnerable to getting severely ill if infected.
"I’m pretty healthy, but I do have gray hair. So when I go out to the supermarket, I’m masked," Schaffner said.
RELATED: CDC: 'No intention of changing' mask guidance 'at this time'
Despite the resurgence in COVID-19 cases, the CDC — which issued guidance in May that said vaccinated people could go without masks in most settings — said last week it is not likely to resurface its policy of recommending masks for everyone "at this time."
But days after the CDC stood firm on its relaxed mask guidelines, Dr. Anthony Fauci said the agency is considering a change as COVID-19 cases climb across the United States.
According to the Associated Press, Fauci told CNN that he’s taken part in conversations about altering the guidelines, something he described as being "under active consideration."
RELATED: CDC weighs revising mask policy, Fauci says
"What I would really like to see is more and more of the leaders in those areas that are not vaccinating to get out and speak out and encourage people to get vaccinated," Fauci said.
Fauci, said some local areas where infection rates are surging are already urging individuals to wear masks in public regardless of their vaccination status.
He said those local rules are not incompatible with the CDC’s recommendation that the vaccinated don’t need to wear masks in public.
This story was reported from Los Angeles.Jordan Smith, KTTV and The Associated Press contributed.