(Editor’s note: This story contains language in the 6th paragraph that some readers may find offensive.)

NEW YORK (Reuters) - From sidewalk shouting matches to politically fueled online sniping, tempers showed signs of fraying in some U.S. cities as the nation stepped up its response to the coronavirus pandemic.

A new fault line appeared in the already-polarized country - between those committed to complying with public health officials urging people to stay home to prevent the spread of disease, and those trying to go about their normal lives outside.

“Flatten the curve, go home! Flatten the curve, go home!” a man in New York’s Brooklyn borough yelled out the window of a four-story apartment building, as people walked on the street below. Three neighbors soon joined in the chiding chorus, which echoed advice to slow the fast-spreading respiratory disease that has infected nearly 179,000 people globally and killed more than 7,000, including at least 74 in the United States.

Joanne Wasserman, a 65-year-old communications consultant, tried to break the monotony of days indoors on Sunday by going for a walk through her Brooklyn neighborhood. While she took care to avoid crowds, she was surprised to see a gaggle of people in their 20s and 30s standing outside a packed restaurant.

“I was shocked,” she said. Heart racing, she summoned the courage to confront them, asking, “Are you guys are aware of what’s going on?”

The response was sudden and severe, she recalled: “We are trying to have a nice Sunday, so why don’t you just fuck off!”

President Donald Trump on Monday urged Americans to halt most social activities for 15 days and not to gather in groups larger than 10 to slow the spread of the disease, also known as COVID-19. Public health officials called the moves necessary to protect older people and those with compromised immune systems, who are more likely to become severely ill.

Stories of charity and compassion have also emerged - teachers raising money for poor kids who will miss meals, or neighbors checking in on each other and sharing cleaning supplies and protective gear like face masks.

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But signs of strain are emerging as the country girds for a long fight.

‘I CAN’T BELIEVE IT’

The most concerned include parents of young children with severe health conditions.

Among them are the Raatz family of Oviedo, Florida.

Their 8-year-old daughter, Ella, has multiple risk factors because of a neurodevelopmental disorder, epilepsy and a primary immunodeficiency.

“People just don’t seem to care about people who might be vulnerable,” said Becky Raatz, Ella’s mother. “Some people are not taking it seriously – when I see the photos of the people cramming into the bars, I can’t believe it.”

She recalled feeling frustrated at a friend who traveled outside the United States and opted against self-isolating on return.

While schools across a large swath of the United States have closed their doors, children still face risks in their communities.

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Tina Raymond, 53, of Warrington, Pennsylvania, said she is deeply angered by what she sees as a nonchalant attitude. She knows the downside better than most: her 13-year-old son, Tim, died in 2010 during the swine flu outbreak.

“He was one of those people who came home from school on a Friday and by Sunday morning he was airlifted to CHOP,” the acronym for Children’s Hospital of Philadelphia, Raymond said.

She is angered by photos she sees on social media of teens in her community gathering at this time.

“They could be infectious already and they’re sharing it with all of their friends,” Raymond said. “I didn’t get this kind of advance warning when the swine flu came around.”

Raymond shared her story and concerns in a public Facebook post: “I am done being nice. STAY HOME AND KEEP YOUR KIDS HOME!”

PARTISAN DIVIDE

Predictably, response to the coronavirus has also broken down along partisan lines, with some Democrats criticizing the Trump administration’s halting early response to the outbreak, and some Republicans downplaying its risks.

Democratic Representative Alexandria Ocasio-Cortez of New York, a rising star on the party’s left flank, on Saturday urged young people to stay home.

“To everyone in NYC but ESPECIALLY healthy people & people under 40 (bc from what I’m observing that’s who needs to hear this again): PLEASE stop crowding bars, restaurants, and public spaces right now. Eat your meals at home,” she said on Twitter. “If you are healthy, you could be spreading COVID.”

The next morning, Republican Representative Devin Nunes of California urged Americans to go out.

“If you’re healthy, you and your family, it’s a great time to go out, go to your local restaurant... let’s not hurt the working people in this country who are relying on wages and tips,” Nunes told Fox News on Sunday. “Go to your local pub.”

That same day, the mayor of Los Angeles ordered all bars and pubs to close.