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Countries across Europe have closed schools, cancelled events, curtailed transport, and quarantined entire cities and regions in response to the coronavirus pandemic. But one European nation has stood apart: Great Britain.

The U.K. has so far not imposed any wide-scale infection-mitigation policies, despite the number of confirmed infections spiking by at least 30% every day. The total number of confirmed COVID-19 cases in the country now stands at 590, with 10 deaths. That’s about half the number of infections confirmed in the U.S. so far, but in a country with a population one-fifth the size.

Until Thursday, the U.K. had officially been on the government’s “Phase One,” response level, which it defines as “containment.” On Thursday evening, Prime Minister Boris Johnson moved the country to “Phase Two,” in which measures are taken to try to delay the peak of the outbreak. His actions have divided health experts, with several prominent experts criticizing the government for doing too little, too late.

The government strategy, Johnson says, is to shift the period in which the greatest number of U.K. COVID-19 infections occur later into the spring, when officials believe the government’s National Health Service will be less overwhelmed with other seasonal ailments and more able to cope with a flood of coronavirus victims. It is also hoped warmer weather may slow the contagion.

‘The right thing, at the right time’

As part of this new phase, Johnson urged people who have a cough or fever, even if mild, to stay home for seven days and advised people over 70 years old to refrain from taking cruises.

But the government has refrained from mandating school closures, recommending the cancellation of large events, the quarantining of entire households, or travel restrictions, which many other European countries have imposed. In fact, Johnson’s chief medical adviser suggested some of those measures might even be counterproductive at this stage of the outbreak.

On Thursday, the prime minister of Ireland—which currently has 61 cases—said he would close schools, and Scotland’s first minister, Nicola Sturgeon, said she had recommended the Scottish government ban all gatherings with more than 500 people. Scotland currently has 60 cases, which are counted as part of the overall U.K. tally. (Johnson says Scotland’s police and ambulance services are more stretched than elsewhere in the U.K., which justified Scotland’s decision.)

“At all stages, we have been guided by science,” said Johnson. “We will do the right thing, at the right time.”

Chris Whitty, the country’s chief medical officer, said the risk was that the government would impose restrictions and cancellations too early—before the infection rate is near its peak. With that peak period still an estimated 10 to 14 weeks away, according to Whitty, people may not be able to bear draconian restrictions for long enough to be effective. Whitty said the early imposition of social distancing would risk self-isolation burnout right when such measures would really be necessary to counter the predicted peak of the infection.

“If people go [into isolation] too early, they get very fatigued, [and] this is going to be a long haul,” Whitty said. “We’re asking people to do something that will interfere with their lives, and social lives, in quite a serious way.”

Those restrictions on the British public would eventually arrive, he and the Prime Minister said.

Proportionate—or dangerous?

During their press conference with Johnson, Whitty and the U.K.’s chief scientific advisor, Patrick Vallance, who is also a medical doctor, said they were looking at behavioral science about what social distancing measure people will actually follow, and for how long, as well as medical information about COVID-19 and how infectious it is.

Whitty, for instance, said that evidence showed that most people will infect only between two and three other people, most often people they live with, and that the disease was more likely to spread in indoor environments. He said as a result, cancelling sporting events, for instance, might be counterproductive, since it would just mean people would stay home and spread the infection there.

The announcement immediately drew a mixed response from experts, with some calling the approach proportionate and others saying that it was likely to be a strategy of too little, too late.

“This is a balanced and measured response. They have clearly come to a different strategy to some other European countries about what to do,” said Jimmy Whitworth, professor of international public health at the London School of Hygiene & Tropical Medicine. “The strategy clearly is going to be flexible and to adapt over time as the circumstances change.”

But Devi Sridhar, a professor of global health at the University of Edinburgh, warned on Twitter of “complacency” within the NHS about the threat of the virus. Criticizing Whitty’s and Vallance’s reliance on modeling—essentially complex simulations—of how COVID-19 might spread in the U.K., she said “models are useful but they’re also often wrong. Just look at E Asian countries to see how models can be proved wrong.”

It is unclear if the fact that the U.K. had still been in the “contain” phase, or its government’s less aggressive response, played any role in U.S. President Donald Trump’s decision to exempt the U.K. from the 30-day travel ban he announced Wednesday on visitors coming from 26 other European nations. Some have suggested that Trump left the U.K. off the list mostly because he has business interests in the country. The White House did not immediately respond to requests for further information on its rationale for exempting Britain for the travel restrictions.

Johnson’s press conference was the Prime Minister’s latest effort to defend a policy that has come under increasing attack, as public calls for a more active response, including cancellations and school closures, has grown.

‘Five day game of cricket’

That approach has provoked heated responses and ridicule on Twitter, with some comparing it to a famous sketch in the comedy television program “Yes, Minister,” about inept government officials. But the government’s position has also drawn increasingly harsh criticism from scientists and health experts.

John Ashton, a former regional director for public health for the northwest of England, told the Guardian that Johnson’s administration was not being transparent and that its coronavirus strategy was weeks behind. He accused the government of behaving “like 19th-century colonialists playing a five-day game of cricket,” a sport known for its languid pace and afternoon tea breaks.

Richard Horton, the medical doctor who serves as editor of the prestigious medical journal The Lancet, was equally scathing, writing on Twitter following the Prime Minister’s latest press conference, “The UK is on the edge of an avoidable calamity. In addition to deaths preventable by more aggressive government action, it will be health workers who absorb the brunt of government complacency.” Horton noted that in the Lombardy region of Italy some 20% of healthcare workers have been infected and that “some have died.”

In a tweet on Wednesday, Horton had lambasted the government for their claim to be “following the science.” “That is not true,” Horton wrote. “The evidence is clear. We need urgent implementation of social distancing and closure policies. The government is playing roulette with the public. This is a major error.”

As of press time, the U.K. Department of Health and Social Care, which Hancock heads, had not responded to requests for further information on what scientific evidence the government has relied on in choosing to defer more rigorous social distancing policies.

Martin Hibberd, professor of emerging infectious disease at the London School of Hygiene and Tropical Medicine, says the U.K. response has “clearly not been sufficient” as the number of cases continues to climb.

But he also said that if the government’s intention was simply to push the peak period of infection further into the summer, as opposed to severely reducing the number of people who are ultimately infected, then it might work. “If the aim is simply to delay the peak of the outbreak till the summer, then perhaps the UK response is enough,” he says.

Hibberd, however, also says that the strict quarantines imposed by countries such as China and Italy are “not an easy path,” and that the U.K. might be better off mimicking the approach of Singapore: rapid tracking and testing of potential cases, paired with social distancing methods that stop short of full-on regional “lock downs” and school closures.

Charlotte Edwards, a professor at University College London’s Institute of Clinical Trials and Methodology, says that the evidence on school closures for fighting outbreaks is also somewhat mixed.

While there is evidence with flu outbreaks, she says, that reducing children’s contact with one another reduces transmissions, a lot depends on how much children continue to associate with other kids. During a prolonged school closure, children might still wind up playing with other children.

In addition, school closures place an additional childcare burden on parents, some of whom may be unable to miss work, and also mean that some poorer children miss out on school meals, she says.