Wednesday, March 25, 2020

The latest study is surprisingly encouraging

Remember this study, from Britain’s Imperial College? That’s the one that convinced Boris Johnson to abandon his plan to ask older people to stay home while letting younger, healthier people essentially go about their business and infect each other. Johnson’s hope was that, because younger adults are better able to weather infection without hospitalization, Britain’s health-care system wouldn’t be overtaxed as they got sick. Then, once more than half of the healthy population had been infected and “herd immunity” had begun to develop, it would gradually become safer to let the older people out of self-quarantine. The problem with that strategy according to the Imperial College is that there would be many thousands of deaths even among the younger, healthier group. Johnson quickly scrapped the plan and turned to aggressive social distancing measures.
Now here comes a study at the University of Oxford that poses a mind-boggling question: What if half of the British population is already infected with coronavirus? What if the percentage of infected people who need hospitalization for COVID-19 is actually teeny tiny because, unbeknownst to us, the overall infected population is actually enormously large? If half of Great Britain is already infected, the country is already well on its way to acquiring herd immunity, which means they may be seeing the worst of the epidemic right now. There’s no true “mass casualty” scenario as the virus spreads. It’s already spread. And it turns out it’s harmless in virtually everyone who gets it.
If the results are confirmed, they imply that fewer than one in a thousand of those infected with Covid-19 become ill enough to need hospital treatment, said Sunetra Gupta, professor of theoretical epidemiology, who led the study. The vast majority develop very mild symptoms or none at all…
The research presents a very different view of the epidemic to the modelling at Imperial College London, which has strongly influenced government policy. “I am surprised that there has been such unqualified acceptance of the Imperial model,” said Prof Gupta…
The Oxford study is based on a what is known as a “susceptibility-infected-recovered model” of Covid-19, built up from case and death reports from the UK and Italy. The researchers made what they regard as the most plausible assumptions about the behaviour of the virus…
If the findings are confirmed by testing, then the current restrictions could be removed much sooner than ministers have indicated.
Gupta didn’t criticize Johnson or his government for locking Britain down. It’s possible that her model is wrong, after all, and if it is, the consequences of letting the disease spread unchecked would be dire. Plus, social distancing measures are helping to limit the spread of the illness at a moment when it may be peaking, which is important to lighten the load on hospitals. Even if the virus only hits one in a thousand infected people hard, an enormous number will need hospitalization at a moment when half the population or so is infected. Locking the country down right now might be the prudent thing to do even if the Oxford model is correct.
But it would also mean the lockdowns could end relatively soon and normalcy could return. There wouldn’t be many months to come of “managing” the epidemic.

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