The warm sands of Miami Beach in Florida are again packed with revelers -- a sight that Americans view either as a proof of progress at last against Covid-19, or of a recklessness that could set back the nation's recovery.

When the coronavirus began to sweep the globe one year ago, many were horrified to see hordes of hard-partying locals and visitors still gathering in Florida while life elsewhere came to a grinding halt.

Every March, during spring break, thousands of people descend on the barrier island of Miami Beach outside the city for a carnival of socializing, drinking, dancing, tanning and late nights.

And after months of depression and isolation, the 2021 season is going with a bang, fuelled by "Roaring Twenties" anticipation of post-pandemic life.

"We just got to start back living, man. For real," says James Mitchell, 45. He has just arrived from freezing Chicago and is sunning himself on a bench on the Ocean Drive promenade.

Mitchell says that a lot has been learned over the past year. His partner Vermell Jones, 44, dismisses criticism against Miami Beach visitors, saying they wear face masks indoors.

"But if you are out in the open walking around, then I feel like you shouldn't have to," she tells AFP.

After a day without much social distancing, the partying takes a wilder turn after dark with twerking on car roofs and some tussles with police.

With 21.7 percent of the US population having received at least one dose of the coronavirus vaccine, many are feeling celebratory, but South Beach resident Esther is "horrified" because she still fears catching Covid-19.

"It's a shame how crowded it is," said the 33-year-old, who declined to give her last name.

The island of Miami Beach only has 92,000 residents, but it attracts 200,000 visitors and workers every day, said Miami mayor Dan Gelber.

"We have seven and a half miles of beautiful beaches, we have hotels that have been very safe, we have tremendous amounts of outdoor dining, but we are not looking for an anything-goes crowd," he warned visitors Monday.

'Tremendous interest'

Americans love to lampoon Floridians, for their over-the-top antics, the animals seemingly running amok in the state, and -- more seriously -- for their allegedly laissez-faire handling of the pandemic.

But now the state says its "open-for-business" stance, its outdoor lifestyle and the arrival of vaccines have proven to be a successful combination to mitigate the effects of Covid-19.

Many who spent months living in pandemic-imposed isolation are moving to Florida precisely because the state's coronavirus restrictions are more lax, and the climate more pleasant.

"There is tremendous interest in moving to Miami for both residential and commercial real estate," said David Nguah of the Douglas Elliman real estate agency. "Almost every showing is (to people) either from New York, California."

"Even with current restrictions in place, they can sit in an outdoor cafe or restaurant, lay by the pool, and... know that they are within a 10 minute stroll or bike ride to an outdoor park," he told AFP.

Real estate sales in Miami were up 16.8 percent over 2020, according to the agency Redfin.

Rahul Sehgal moved last November from New York, as part of a tech boom in Miami.

"It was too cold to be dining outside, indoor dining closed, too cold to be socializing in the park, and people hesitant to socialize indoors," said the 49-year-old computer engineer.

But in Miami, "I would... have a little bit of a social life and be at least happier outside even if I didn't know a lot of people."

'Better than expected'

Florida has recorded no more coronavirus deaths than other states that have stayed in lockdown.

It is the 27th out of 50 states for number of Covid-19 deaths per 100,000 residents, with 150 fatalities -- far below New York, for example, which is second with 252, according to data from Johns Hopkins University.

"There's a real phenomenon there," Amesh Adajla, a professor at Hopkins's Bloomberg School of Public Health, told AFP. "It's clear that Florida did better than we all predicted it would do."

It may have to do with the weather, he says, or it could be that in states with stricter measures, people meet in secret -- which ends up being riskier because the gatherings are held in private residences.

Florida's Republican governor, Ron DeSantis, closed the hundreds of nursing homes for the elderly -- who make up 20 percent of the population -- but never mandated face masks at the state level.

Restaurants opened back in May, the last of the beaches reopened in June after some closed for just a few months, and schools began holding in-person classes last summer.

Malena Mateos, a 44-year-old Miami Beach resident, says at one point Florida gave the impression that the state had decided to simply "take the casualties that Covid was going to cause."

But it was also true that "we live in a privileged environment."