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Italians, their country locked down with the world’s second-highest number of Covid-19 infections after China, are sounding a dire warning for other countries about what could be in store for them if they don’t take the pandemic seriously.

Italy’s coronavirus infections have surpassed 24,000. Over the weekend, the country reported 368 deaths in 24 hours ― a toll that exceeded China’s highest single-day number at the height of its outbreak, according to The New York Times.

Humbled by the experience of showing the world what not to do, quarantined Italians, including health care workers, are sharing what they’ve learned, admonishing people to take the virus seriously and to heed advice not to gather.

“In Italy we waited too long, these countries should really start implementing aggressive containment measures now,” Italian researcher Silvia Merler wrote on Twitter last week. She posted a “lag tracker” graphic showing Covid-19 cases in the US and other countries are now following the trajectory of the outbreak in Italy 13 to 16 days earlier.

Other Italians also are using Twitter to tell people that their situation is “not good” and that they should learn from Italy’s “mistakes.”

Dr Marco Vergano, an anaesthetist at San Giovanni Bosco hospital in Turin, told HuffPost via email that it’s “evident” to him that “acting like a community, rather than personally feeling violated in individual freedom will be more difficult for Americans than for Europeans.”

Americans, Vergano said, “should stop believing that Covid-19 is a ‘bad flu’” and “stop circulating low-quality information and ‘fake news.’”

The US “should abandon woefully incompetent political leaders, that in an unprecedented emergency like this can lead the country to a catastrophe,” Vergano advised. “They should not panic, but in case restrictive measures are difficult to enforce without panic, well… then a bit of ‘fruitful panic’ may be useful!” He said Americans should take “advantage of the few weeks between Italy and US.”

Cristina Higgins, who lives in Bergamo, wrote on Facebook last week that Americans and some Europeans “are weeks away from where we are today in Italy.”

“You have a chance to make a difference and stop the spread in your country,” Higgins wrote. “Push for the entire office to work at home today, cancel birthday parties, and other gatherings, stay home as much as you can. If you have a fever, any fever, stay home. Push for school closures, now. Anything you can do to stop the spread because it is spreading in your communities – there is a two week incubation period – and if you do these things now you can buy your medical system time.” 

Dr Daniele Macchini, who’s also from Bergamo, wrote in a heartbreaking Facebook post that Italy has so many patients it’s impossible to give all of them adequate care.

“The display boards with the names of the sick, of different colours depending on the operating unit they belong to, are now all red and instead of the surgical operation there is the diagnosis, which is always the same cursed: bilateral interstitial pneumonia,” Macchini wrote in her essay, according to a translation.

“The epidemiological disaster is taking place. And there are no more surgeons, urologists, orthopedists, we are only doctors who suddenly become part of a single team to face this tsunami that has overwhelmed us,” Macchini wrote. “The cases multiply, we arrive at the rate of 15-20 hospitalizations a day all for the same reason. The results of the swabs now come one after the other: positive, positive, positive. Suddenly the emergency room is collapsing.” 

Macchini warned people to stay away from “the theater, museums or gym” and to have “mercy on that myriad of older people you could exterminate.”

“Please, listen to us, try to leave the house only to indispensable things,” he added.

Roberta Re, a nurse at Piacenza hospital in Emilia-Romagna, told The Guardian that working to help people recover from the coronavirus is akin to “a world war.”

“But it’s a war that isn’t fightable with traditional arms ― as we don’t yet know who the enemy is and so it’s difficult to fight,” Re said. “The only weapon we do have to avoid things getting even worse is to stay at home and to respect the rules, to do what they did in China, as this is paying off.” 

Giacomo Grasselli, a senior Italian health official working in Lombardy, likened the coronavirus escalation to “a bomb that exploded.”

“Everything happens very quickly, if one had told me that in two weeks we would have created 500 new ICU beds … I would have said ‘OK you’re crazy,’” Grasselli told the United Kingdom’s Channel 4. 

“Everyone must understand” what he said is “very, very important for every country,” namely “to behave in some way in order to avoid the spread of the disease.” 

Many Americans appear to be ignoring the message. Despite warnings to avoid public spaces and crowds, many people over the weekend continued gathering at restaurants, bars and other places as they normally would in a world without a pandemic.

On Baltimore’s historic Fort Avenue, “every bar and restaurant is packed,” a Baltimore Sun reporter tweeted on Friday. In New York City on Saturday night, people waited in a long line to crowd into a bar.

In Washington, DC, dozens of people waited to get inside the bar Sauf Haus.

And in Florida, Disney World looked typically congested.

The US Centers for Disease Control and Prevention on Sunday released new advice that goes along with some of what the Italians are saying, suggesting that gatherings of more than 50 people should be cancelled or postponed for at least eight weeks. Some states and local governments imposed their own rules, closing schools, restaurants and bars.

Whether the measures will help curb the coronavirus is yet to be seen. But perhaps it’s time to hunker down and listen to the Italians.