The New Science of Lockdown

Nature news has this piece on the science of lockdowns during the COVID pandemic.  My own personal view is that we will not be in a position to even begin an assessment of the net effect of the harms of lockdown until 3-5 years from now, so it is a bit premature to suggest we are in an epistemic position to make firm proclamations.  What is clear by now we is that lockdowns (at least when they were implemented) failed to eradicate the virus, and it has subsequently spread to every country in the world.  

Locking down billions of humans to try to eliminate a respiratory virus has never been tried before.  So the science of lockdowns is really "experimental science" on a grand scale.  I still find it surprising that even Nature frames the piece as if there was real success stories (I suppose if delaying the spread of the virus constitutes a "success", but only if an island or authoritarian regime).  A sample from the article:

Restrictions on social contact stemmed disease spread, but weighing up the ultimate costs and benefits of lockdown measures is a challenge.

Scientists have been studying the effects of lockdowns during the pandemic in the hope that their findings could inform the response to future crises. They have reached some conclusions: countries that acted quickly to bring in stringent measures did best at preserving both lives and their economies, for instance. But researchers have also encountered difficulties. Analysing competing harms and benefits often comes down not to scientific calculations, but to value judgements, such as how to weigh costs that fall on some sections of society more than others. That is what makes lockdowns so hard to study — and can lead to bitter disagreement.

....Other studies have tried to put more precise figures on the effects of lockdown policies, but their findings differ. An analysis8 of 41 countries in Europe and elsewhere found that stay-at-home orders had a relatively small impact on transmission, reducing R — the average number of people that one person with COVID-19 will go on to infect — by just 13% beyond what could be achieved by closing schools and universities (38%) or limiting gatherings to 10 people or fewer (42%). Yet Bhatt’s analysis4 of 11 countries suggested that stay-at-home orders cut R by 81%, with school closures, public-event bans and other measures being less important. Klimek warns against generalizing about the effectiveness of lockdown policies on the basis of figures such as these. “The effectiveness of each intervention is highly context dependent,” he says. What several analyses suggest is that no single intervention can reduce R to below 1 (signifying that infections are declining): multiple measures achieve this by working in concert.

....And lockdown policies did bring costs. Although they delayed outbreaks, saving lives by allowing countries to hang on for vaccines and drugs, they also brought significant social isolation and associated mental-health problems, rising rates of domestic violence and violence against women, cancelled medical appointments and disruption to education for children and university students. And they were often (although not always) accompanied by economic downturns.

Science has had many triumphs and successes over the past two centuries.  I am confident that the prolonged lockdown measures implemented during this pandemic will not be included among the list of defensible public health measures for today's aging populations.  Sadly progress in science is sometimes a "one step forward, two steps back" type of thing.

Cheers, 

Colin