President Donald Trump is famously unpersuaded by scientists — just ask scientists who have tried talking to him about climate change — but his abrupt recommendation of strict social distancing to fight the spread of Covid-19 is reportedly motivated by a dire report from the Imperial College of London estimating as many of 2.2 million people in the US could die without strict measures.
“It’s bad,” Trump said Monday as the White House recommended people avoid gathering in groups of more than 10, a much stricter recommendation that the CDC’s advise to avoid groups of 50 or more.
The estimate of 2.2 million deaths assumed no measures were taken to limit gatherings. In actuality, some state and local governments have closed schools, shutdown bars and restaurants, and exhorted the populace to work from home to minimize contagious contact. While these are the sorts of measures the report argues are needed to stem the pandemic, the authors warn they must continue until a vaccine is available, which is not expected sooner than 18 months.
“No public health intervention with such disruptive effects on society has been previously attempted for such a long duration of time,” they added. “How populations and societies will respond remains unclear.”
The report divides non-pharmaceutical interventions (NPIs) into two categories, suppression and mitigation. Suppression aims to eliminate human-to-human spread of the disease through mandatory measures such as closing schools and “locking down” entire regions, as was done in China and is being done in Italy. Mitigation seeks to slow the transmission of disease to “flatten the curve” to limit overwhelming hospitals, and especially intensive care units.
The choices are stark. “Suppression, while successful to date in China and South Korea, carries with it enormous social and economic costs which may themselves have significant impact on health and well-being in the short and longer-term,” the report stated. “Mitigation will never be able to completely protect those at risk from severe disease or death and the resulting mortality may therefore still be high.”
The report estimates mitigation measures such as isolating patients, quarantining those in contact with them and isolating the most vulnerable people for three months would reduce the death toll by half, which is still more than a million people in the US.
“The effectiveness of any one intervention in isolation is likely to be limited, requiring multiple interventions to be combined to have a substantial impact on transmission,” the authors wrote.
Epidemiology professor Neil Ferguson, the lead author of the study, told the New York Times that measures to effectively suppress the Covid-19 virus, which he compared to the infamous 1918 influenza epidemic, will need to continue for far longer than has been discussed publicly, at least so far.
“We don’t have a clear exit strategy,” Dr. Ferguson said of the recommended measures. “We’re going to have to suppress this virus — frankly, indefinitely — until we have a vaccine. It’s a difficult position for the world to be in.”