After several weeks at a plateau, Covid-19 cases in the United States are rising again, the clearest warning sign yet that the country could face another "avoidable" surge, the head of the Centers for Disease Control and Prevention said Friday.
The uptick comes at a critical time, when Americans are exhausted and desperate for a return to normalcy, but also perhaps better equipped than at any other point in the pandemic to turn the tide, thanks to increased vaccine supply.
CDC Director Dr. Rochelle Walensky said at a media briefing that the most recent seven-day average of Covid-19 cases was about 57,000 cases per day, an increase of 7 percent from the previous week.
"We know from prior surges that if we don't control things now, there is a real potential for the epidemic curve to soar again," she said, adding that she remains "deeply concerned" about the trends.
The immediate challenge for Walensky and other public health officials is to convince Americans weary of pandemic protocols to hold on just a little longer with masks and physical distancing as vaccinations are administered at an average clip of 2.5 million per day. Still, just 14 percent of the U.S. population is fully vaccinated, according to the CDC.
But are Americans, or their elected leaders, listening?
The urgent pleas from public health officials come as a growing number of states have begun to relax mitigation strategies.
"Elected leaders are undermining public health messaging left and right," said Brian Castrucci, president and chief operating officer of the de Beaumont Foundation, a public health nonprofit.
Arizona is the latest state to announce it's lifting mask mandates and is allowing bars and restaurants to reopen fully — joining Iowa, Mississippi, Montana, North Dakota and Texas.
As of Friday afternoon, many North Carolina businesses, including retail stores, were permitted to reopen fully. Connecticut and Maryland, too, have announced plans to roll back mitigation efforts.
In a statement to NBC News, Walensky acknowledged her team is "competing against messages from states that are pulling back public health measures, like mask-wearing requirements and relaxing limits on in-person dining in restaurants and bars."
"We're also communicating with a fatigued public," she said following Friday's briefing in which she urged people to stay the course.
"We can turn this around, but it will take all of us working together."
It seems, however, that many people are rejecting the idea. Spring break hot spots are crowded. Many bars and restaurants are filled to capacity.
"Clearly, it's not working," said Dr. Leana Wen, an emergency physician and a former health commissioner of Baltimore. "It doesn't work if we tell them, 'don't travel, don't party,' because they're doing it."
Wen said the best strategy is to communicate ways to minimize, not necessarily eliminate, risk.
Forcing spring breakers off beaches or out of other outdoor venues may have the unintended impact of driving such gatherings underground, to more dangerous situations.
"Now instead of gathering in outdoor bars, they're going to be in somebody's hotel room with 10 people to a room that's not well ventilated," Wen said.
This whole pandemic is a monument to our inability to effectively communicate.
The mixed messaging is not surprising to Castrucci. "This whole pandemic is a monument to our inability to effectively communicate," he said.
Beyond changing messaging strategies about safer gatherings, it's worth reminding people that the end may be in sight.
Dr. Julie Morita, executive vice president of the Robert Wood Johnson Foundation, describes the current U.S. pandemic situation as nearing the end of a marathon.
"It'd be so much easier just to stop and relax and let our guard down and forget about social distancing and avoiding large crowds," said Morita, who also served as a former health commissioner at the Chicago Department of Public Health. "But we can actually do this. The finish line is in sight."
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Indeed, that's the message Walensky said she tries to convey on weekly calls with governors, encouraging "them to hold on for just a little while longer."
"We certainly understand that people are tired," Jeff Zients, coordinator for the Biden administration's Covid-19 task force, said during Friday's briefing. "But we can't let our guard down."
Castrucci suggests a different public health communication tactic: Rather than focus on mitigation, keep the spotlight on vaccinations.
And, he said, let the messages come from people who are not politicians, such as faith leaders, physicians and everyday people.
"The more people who get the vaccine, the more they can tell folks, 'Gee, I feel great,' or, 'I didn't have any side effects' or 'I didn't turn into a zombie,'" Castrucci said.
"We need to have a constant drumbeat of this conversation."