Alarming surges in coronavirus cases across the US south and west have raised fears the outbreak is spiralling out of control.

Concerns are deepening that hard-won progress against the disease is slipping away because of resistance among many Americans to wearing masks and keeping their distance from others.

Coronavirus graphic
(PA Graphics)

It comes as Donald Trump said on Monday the US had done “too good a job” on Covid-19 testing, even as his staff insisted the president was joking when he said on the weekend he had instructed aides to “slow the testing down, please”.

Confirming predictions the easing of state lockdowns in the past six weeks would lead to a comeback by the virus, cases have surpassed 100,000 in Florida, hospital admissions are rising dramatically in Houston and Georgia, and a startling one in five of those tested in Arizona are proving to be infected.

Over the weekend, the virus seemed to be everywhere at once: Several campaign staff members who helped set up President Donald Trump’s rally in Tulsa, Oklahoma, tested positive, as did 23 Clemson University football players in South Carolina. Meatpacking plants were also hit with outbreaks.

Virus Outbreak Arizona
People line up to get tested for Covid-19 in Phoenix, Arizona, at a drive through testing site hosted by the Puente Movement, a migrant justice organisation. Arizona has a large population of Latinos, who have been statistically shown to be especially vulnerable to infection, partly because they tend to live in tight quarters with multiple family members and have jobs that expose them to others (Matt York/AP)

“It is snowballing. We will most certainly see more people die as a result of this spike,” said Dr Marc Boom, CEO and president of Houston Methodist Hospital, noting the number of Covid-19 hospital admissions had tripled since May 25, to more than 1,400 in the Houston metropolitan area.

He warned hospitals could be overwhelmed in three weeks, and he pleaded with people to cover their faces and practice social distancing.

Texas is among a number of states — including Arizona, Alabama, Florida and South Carolina — whose governors have resisted statewide mask requirements, leaving the matter to local authorities.

The number of new coronavirus cases across the country per day has reached more than 26,000, up from about 21,000 two weeks ago, according to an Associated Press analysis of data compiled by Johns Hopkins University. More than 120,000 deaths in the US have been blamed on the virus, the highest toll in the world.

Donald Trump
Donald Trump, carrying a Make America Great Again cap as he returns to the White House from his disastrous Tulsa rally on Saturday night, continues to insist his country’s Covid crisis looks worse than it is because of its numbers of tests (Patrick Semansky/AP)

In Georgia, the number of people admitted to hospital with Covid-19 rose to 1,000, erasing a month’s worth of progress.

Infections are at their highest level since the outbreak began, nearly two months after Georgia began lifting restrictions on businesses. Governor Brian Kemp has required face coverings by waiters, barbers and others working face-to-face with customers but has largely let businesses decide whether customers must wear masks.

In Orlando, Florida, 152 coronavirus cases were linked to one bar near the University of Central Florida campus, said Dr Raul Pino, a state health officer in the tourism city.

“A lot of transmission happened there,” Dr Pino said. “People are very close. People are not wearing masks. People are drinking, shouting, dancing, sweating, kissing and hugging, all the things that happen in bars. And all those things that happen are not good for Covid-19.”

In Florida, governor Ron DeSantis has not signalled any retreat from reopening the state after three months of shutdowns that have damaged the economy.

In Louisiana, however, governor John Bel Edwards extended restrictions on businesses because of a troubling upswing in cases. Louisiana has recorded more than 3,000 deaths.

“There are a lot of people out there saying they are done with this virus. Well, the virus isn’t done with us,” Mr Edwards said.

Countries such as Brazil, India and Pakistan are also seeing surging cases.

Dr Michael Ryan, the World Health Organisation’s emergencies chief, said the outbreak was “definitely accelerating” in the US and some other countries, dismissing the notion that the record-breaking daily levels of new cases simply reflected more testing.

“The epidemic is now peaking or moving towards a peak in a number of large countries,” he warned.

This clashes with what Mr Trump said again in a tweet on Monday that testing in the US “makes us look like we have more cases”.

In the US, Arizona, in particular, is seeing disturbing trends, including the percentage of tests that prove positive for the virus. Arizona’s is the highest in the nation, at more than 20%, well above the national average of 8.4% and the 10% level that public health officials regard as problematic.

Meanwhile, asked in a TV interview on Monday if he did indeed tell aides to “slow it down” on testing, Mr Trump did not directly answer but replied: “If it did slow down, frankly, I think we’re way ahead of ourselves.”

“We’ve done too good a job,” he added, saying again the reason the US had more coronavirus cases was that it did more testing.

White House press secretary Kayleigh McEnany said any suggestion testing had been curtailed was not rooted in fact, saying Mr Trump made the slow-it-down comment “in jest.”