Hospitals across the United States have warned they are at risk of being overwhelmed as health officials fear that a weekend of picnics, pool parties and beach outings for the Independence Day holiday could fuel the worsening coronavirus outbreak.

The warnings come as the death toll from the virus passed 130,000 in the United States, according to figures compiled by Johns Hopkins University.

Confirmed cases are on the rise in 41 out of 50 states, plus the District of Columbia, and the percentage of tests coming back positive for the virus is increasing in 39 states.

Florida, which recorded an all-time high of 11,400 new cases over the weekend and has seen its positive test rate lately reach more than 18 per cent, has been hit especially hard along with other Sunbelt states such as Arizona, California and Texas.

Hospitalisations across Florida have been ticking upward, with nearly 1700 patients admitted in the past seven days compared with 1200 the previous week.

Five hospitals in the St Petersburg area were out of intensive care unit beds, officials said. Miami’s Baptist Hospital had only four of its 88 ICU beds available.

“If we continue to increase at the pace we have been, we won’t have enough ventilators, enough rooms,” said David De La Zerda, ICU medical director and pulmonologist at Miami’s Jackson Memorial Hospital.

In Miami-Dade County, population 2.7 million, Mayor Carlos Gimenez ordered the closing of restaurants and certain other indoor places, including vacation rentals, seven weeks after they were allowed to reopen.

Beaches will reopen on Tuesday (local time) after being closed over the weekend.

“But if we see crowding and people not following the public health rules, I will be forced to close the beaches again,” the mayor warned.

Officials in Texas also reported hospitals are in danger of being overwhelmed. Hospitalisations statewide surged past 8000 for the first time over the weekend, a more than fourfold increase in the past month.

Houston officials said intensive care units there have exceeded capacity.

California Governor Gavin Newsom said the number of people hospitalised with COVID-19 had increased by 50 per cent in the past two weeks, up to 5800 people.

Health officials said a quarter of these were people aged between 18 and 40, as new cases increasingly hit a younger population that may have been lax about safety precautions in recent weeks.

Similar increases in the number of hospitalisations were reported in Arizona and South Carolina.

Fears July 4 celebrations could fuel rise

There are fears that events held over the holiday weekend could fuel the spread of coronavirus. Photo: AP

Health officials voiced fears that large gatherings over the Independence Day holiday weekend could add to the rise in cases.

“We were concerned before the weekend and remain concerned post-holiday, as anecdotal stories and observed behaviour indicate that many continue to disregard important protective guidance,” said Heather Woolwine, a spokeswoman for the Medical University of South Carolina.

Alabama has been averaging about 1000 new cases a day, two or three times what it was seeing in late April, when its stay-at-home order was lifted.

“We set a record for highs over the holiday weekend, and, of course, given the number of people who were out and about over the weekend celebrating, we are certainly concerned about what the next couple of weeks are going to look like as well,” said Scott Harris, Alabama’s health officer.

In New York, once the most lethal hot spot in the country, Governor Andrew Cuomo said he was concerned about reports of large gatherings over the holiday weekend in New York City, on Fire Island and other places.

“I understand people are fatigued,” he said. “We’ve been doing this for 128 days. I get it. But it doesn’t change the facts, and we have to stay smart.”

Meanwhile, three of the top US medical organisations issued an open letter urging Americans to wear masks, social distance and wash hands often to help stop “the worst public health crisis in generations”.

The American Medical Association, American Nurses Association and American Hospital Association issued the plea in the absence of a mask-wearing order from Washington and said steps taken early on that helped slow the spread of COVID-19 “were too quickly abandoned.”

In West Virginia, Republican Governor Jim Justice reversed course and ordered the wearing of face masks indoors.

“I’m telling you, West Virginia, if we don’t do that and do this now, we’re going to be in a world of hurt,” he said, adding: “It’s not much of an inconvenience.”

The White House again rejected calls for a nationwide order to wear face coverings, with White House chief of staff Mark Meadows saying on Fox News that it is a matter for governors and mayors to decide.

-ABC