US COVID-19 deaths top 250,000 as New York City schools halt in-person classes

The US death toll from COVID-19 surpassed a grim new milestone of 250,000 lives lost on Wednesday, as New York City's public school system called a halt to in-classroom instruction.

The decision to shutter schools and revert exclusively to at-home learning, starting on Thursday, came as state and local officials nationwide imposed restrictions on social and economic life to tamp down a surge in COVID-19 cases and hospitalisations heading into winter.

But eight months after New York City emerged as the nation's first major flashpoint of the epidemic - its hospitals besieged and streets virtually devoid of human activity - the epicentre of the public health crisis has shifted to the upper Midwest.

Governor Tim Walz of Minnesota, one of several states in the region dogged by the country's highest case rates per capita, ordered all restaurants, bars, fitness centres and entertainment venues closed, and all youth sports cancelled, for four weeks.

More than 90 per cent of hospitals' intensive-care unit beds are already occupied in the eastern half of the state, Walz told an evening news briefing, adding: "We are at a dangerous point in this pandemic."

The action by New York schools, announced by Mayor Bill de Blasio via Twitter, doubtless came as a relief to some teachers, many of whom have expressed fear of being placed at increased risk of exposure to the highly contagious respiratory virus.

But it will bring renewed hardship for working parents forced to make childcare arrangements once more.

New York City has seen a late-autumn resurgence of the virus after a summertime lull. Schools have been following a staggered, part-time system of classroom instruction since September, with 1.1 million students dividing their school week between in-person and online learning.

But de Blasio said all instruction would switch back to distance learning again because the positive rate on coronavirus tests in the city rose to a seven-day average of 3 per cent, the threshold for ceasing in-person classes.

"We must fight back the second wave of COVID-19," he said.

New York joins other large school districts in cities like Boston and Detroit that have recently cancelled in-person learning. Within the past week, the Clark County School District, which includes Las Vegas and is the fifth-largest in the United States, and Philadelphia's public school system both postponed plans to return to in-person instruction.

As of Wednesday, COVID-19 had claimed at least 250,016 lives in the United States, which has documented about 11.5 million infections since the pandemic emerged, according to a Reuters tally of public healthcare data. The United States leads the world in both categories.

More than 1,400 of those victims perished during the past 24 hours.

Nearly 79,000 COVID-19 patients were reported in US hospitals as of Wednesday, the highest number yet for a single day, up from about 75,000 on Tuesday, Reuters' tally showed.

Health experts say greater social mixing and indoor gatherings during the holiday season, combined with colder weather, could accelerate the surge, threatening to overwhelm already strained healthcare systems.

NBC News reported on Wednesday that more than 900 Mayo Clinic personnel in Minnesota and Wisconsin had been diagnosed with COVID-19 in the past two weeks - nearly a third of the cases among the medical centre's Midwestern staff since March.

The Midwest has become the new US epicentre of contagion, reporting almost a half-million cases during the week ending on Monday.

Government officials in at least 21 states, representing both sides of the US political divide, have issued sweeping new public health mandates this month. Those range from stricter limits on social gatherings and non-essential businesses to new requirements for wearing masks in public places.

Forty-one U.S. states have reported daily record increases in COVID-19 cases in November, 20 have registered all-time highs in coronavirus-related deaths from day to day and 26 have reported peaks in hospitalizations, according to the Reuters tally.

In Washington, pressure for a fresh COVID-19 economic relief bill mounted in Congress. Senate Democrats also unveiled legislation to ramp up the national supply of personal protective equipment for healthcare and other frontline workers.