U.K.’s Boris Johnson, who initially advocated herd immunity, becomes symbol of the strategy’s danger

April 6, 2020, 11:00 PM UTC

Boris Johnson, the British Prime Minister, who was transferred to intensive care Monday night, has become a potent symbol of the dangers the coronavirus pandemic poses.

The fact Johnson has become so ill highlights that this disease can be deadly to even the young and healthy. It also highlights what’s so problematic about the policy his government initially pursued to combat the virus: herd immunity.

Johnson’s government was much slower to impose social distancing measures than many other European countries.

On March 12, the same day that France closed schools and asked companies to institute work from home policies, Johnson addressed the British public and declared that the U.K.’s attempts to contain the coronavirus outbreak, with quarantines, testing, and contact tracing, had also failed.

“I must level with you, level with the British public, many more families are going to lose loved ones before their time,” Johnson said.

The U.K. would now move to a new phase in its strategy against the pandemic, trying to delay the peak of the outbreak, flattening the curve to prevent the National Health Service from being overwhelmed.

But Johnson did not follow France’s lead, instead simply suggesting the vulnerable older people refrain from going on cruises, that schools consider canceling international class trips, and that people with coronavirus symptoms should self-isolate for seven days.

His government was pursuing a strategy that rested, at least in part, on the idea of shielding the most vulnerable members of the British public from infection while allowing a large percentage of others to catch the virus. The hope was that most of these people would experience relatively mild symptoms, recover, and wind up immune, stopping the virus’s further transmission.

But this kind of herd immunity, experts said, could require upwards of 60% of the population becoming infected. Herd immunity as a deliberate policy, epidemiologists said, is usually achieved through a vaccination program. It was untested as a tool for responding to a pandemic.

Epidemiologists and medical experts immediately assailed the plan as a dangerous gamble. And, when epidemiologists at Imperial College London, who had been advising the government on the likely spread of the virus, updated their models to take into account information on the number of hospital patients requiring intensive care in Italy, it became apparent that the minimal, voluntary restrictions Johnson had suggested were unlikely to save the NHS from being overwhelmed.

On March 16, just four days after unveiling its herd immunity strategy, Johnson reversed course, ordering all citizens to “stop non-essential contact with others and to stop all unnecessary travel.” All those who could, needed to work from home. Those over 70 years old or suffering from health conditions were told to isolate themselves at home for up to 12 weeks. If anyone in a household showed symptoms, the entire household was now advised to self isolate for 14 days.

Despite the stunning reversal and further restrictions, including the closure of schools, announced on March 18, questions remained about whether herd immunity did not, in fact, remain a part of the government’s strategy.

Epidemiologists, such as Devi Sridhar, Chair of Global Public Health at the University of Edinburgh, have said that even if the government has now abandoned the controversial idea completely, it lost valuable time preparing for the disease.

For instance, the U.K. has been forced to admit it did not order enough COVID-19 test kits to test large segments of the population. Perhaps because, if it assumed most people would become infected anyway but only experience mild symptoms, such testing would be unnecessary.

But that failure to prepare has left the U.K. lagging far behind other nations in testing. As of today, the country had tested 208,000 people, a fifth of the number of people Germany had tested.

This lack of testing has been a particularly acute problem for NHS staff, who are forced to take time off work if they or someone in their household exhibits mild symptoms, but who may, in fact, not be infected. Some hospitals have reported that as much as a third of their staff is currently off sick or self isolating.

The government has also been criticized for failing to provide enough personal protective equipment for frontline medical staff and a shortage of other critical equipment, including ventilators.

Most critically, Johnson’s herd immunity strategy rested on the premise that most of those who would become gravely ill with COVID-19 would be the elderly and those with pre-existing conditions. That remains true, statistically.

But the 55-year-old’s own life-threatening fight with the virus shows that even those in their prime and without serious health issues are vulnerable. Johnson’s illness has shaken many in Britain from any lingering complacency.

Johnson tested positive for coronavirus on March 27 and had reportedly been experiencing mild symptoms including a high temperature and cough, before being brought to the hospital on April 5 on what was described as ‘precautionary’ measures.

On the evening of April 6, Johnson was transferred to the ICU.

Until late Monday, the government said Johnson was still in charge of the government. His administration said at the time that if he became unable to work, foreign secretary Dominic Raab would step in.

The last official communication from Johnson came in a tweet at 1:20 p.m. London time. The Prime Minister said he was “in good spirits” in the hospital and that he was “keeping in touch with my team.” He also thanked “all the brilliant NHS staff taking care of me and others in this difficult time. You are the best of Britain.”

But some are questioning whether those NHS staff, in whose hands Johnson’s life may now rest, have had their jobs made more difficult by the policies his government chose to pursue in addressing this pandemic.

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