despite issues, science suggests covid lockdowns work
6 minute read
like it or not, restricting human-to-human contact has been key to curbing the spread of covid-19.
peter j. thompson/national post
dr. ari joffe is accustomed to being at odds with his scientific colleagues.
the university of alberta critical care physician doubts brain death really is death and questions the practice of harvesting donor organs from people shortly after their hearts have stopped beating.
he did it again last month, publishing a paper that argues the lockdowns used to curb the spread of covid-19 stem from “group-think” and have done more harm than good.
“we must open up society to save many more lives than we can by attempting to avoid every case (or even most cases) of covid-19,” joffe urged in the journal frontiers of public health.
worn out by a year of life in suspension, many canadians would likely share his sentiments.
in the battle against the coronavirus, lockdowns have been bitter medicine, causing unemployment not seen since the great depression, wiping out myriad businesses, costing government billions and triggering countless mental and physical health side effects.
it’s not over, either, with curfews still in effect in quebec and ontario pondering a new, three-week freeze.
some medical outliers go further than joffe, questioning whether the measures even work.
but as it turns out, science has taken a hard look at that issue, and has some answers.
advertisement
though they’ve differed on the details, the scores of studies examining the policies’ impact have mostly come to similar conclusions: like it or not, restricting human-to-human contact has been key to curbing the virus’s spread. and helping prevent grim scenarios of death and grave illness.
“all you have to do is look at the places that have had big lockdowns,” says dr. mark jit, an epidemiology professor at the u.k.’s london school of hygiene and tropical medicine. “you can see that the peak in the number of cases is a few days after the lockdown, and then the cases just keep dropping.”
there was an element of flying blind in imposing strict containment measures at first, but studies by jit’s team and others have more recently examined real-world data on lockdowns and their effects.
no single weapon in the arsenal of “non-pharmaceutical interventions” (npis) is a silver bullet, says peter klimek, a physicist at the medical university of vienna in austria, who studies health systems. but combinations of policies — from border restrictions to banning gatherings of more than 10 people — do seem to curb cases, he said.
acting early is the key to avoiding long-term or repeated lockdowns, his research indicates.
advertisement
“if you wait for too long, you have to use higher and higher measures to gain control of the situation,” said klimek in an interview.
in england reviewed 348 other studies and found they “unanimously show” the importance npis to slow covid-19’s spread.
a study from south korea, which has both controlled its case numbers and deaths and allowed its economy to largely stay open, estimates that infections would have soared 27-fold early in the pandemic if not for strict counter-measures.
it may take years to tease out exactly what worked — wearing masks in public places, for instance, versus keeping people at home, says dr. prabhat jha, a university of toronto epidemiologist and head of the centre for global health research.
but doing nothing clearly was not a successful strategy, he said.
“one thing you can say is that the governments that took covid seriously did better by far than those that didn’t.”
there have been, though, some alternative takes on what’s happened.
a recent brazilian paper in the journal nature scientific reports did head-to-head comparisons between similar places worldwide that, in the authors’ view, were either “controlled” or “uncontrolled” in terms of keeping people inside.
advertisement
in all but two per cent of the comparisons, there was no evidence that lockdowns reduced the number of covid deaths per capita, the scientists concluded.
differences in treatment methods and the disease’s natural course might be a more important factor, they suggested.
but at least one of the comparisons seems to raise questions about the methodology. the study describes australia, which has had among the lowest covid death rates in the world, as uncontrolled and canada as controlled. yet australia — while avoiding long-term stay-at-home orders — has still imposed some draconian measures, including hard border closures, mandatory hotel quarantine for arriving travellers and targeted lockdowns.
a march 11 editor’s note says the paper has faced criticism and that the journal plans to respond.
skeptics of dramatic public health measures also frequently point to florida. while it has imposed relatively few restrictions, its covid toll is in the middle of the pack among u.s. states. yet florida’s per-capita death rate is still 2.5 times higher than canada’s after a series of lockdowns here, the equivalent of 33,000 more deaths in this country.
meanwhile, many of the most recent studies have tried to disentangle the various npis to gauge which is most effective at arresting the virus’s spread.
advertisement
jit and colleagues’ recent paper in the journal bmc medicine looked at 130 countries, comparing their covid strategies in the pandemic’s first months to the rise and fall of coronavirus cases.
they concluded that closing schools and restricting internal movement of people had a particularly strong effect on the virus’s spread, as did shuttering workplaces and providing income support to those affected by the measures.
“there’s no easy answers,” he said in an interview about the policies, some of them undeniably controversial. “no cheap, magic bullet.”
klimek and colleagues recently posted a study — yet to be peer-reviewed — that ranked numerous measures in over 200 countries according to their effectiveness in slowing the virus’s transmission.
eliminating small gatherings with measures like closing non-essential businesses and restricting the size of family get-togethers topped the list, followed by shutting educational institutions, imposing border restrictions and increasing use of masks and other personal protective equipment.
a december study of several countries in the journal science by researchers from oxford university came to similar conclusions. closing schools, limiting the size of gatherings and shutting “face-to-face” businesses had the greatest impact, the researchers said.
advertisement
a study by hong kong and chinese academic researchers looked at 190 countries early in the pandemic. it suggested that social distancing steps like school closures, restricting restaurant use, and shutting non-essential businesses were the most effective.
still, for many lay people and some doctors and scientists , the question has become: was it all worth it?
joffe says the lockdown measure may have helped flatten the epidemic curve and reduce the burden on health care, but he contends the collateral damage in terms of reducing “wellbeing years” over the long term is five to 10 times greater.
many of the studies that document the tactics’ effectiveness acknowledge they come at a steep social and economic cost.
but klimek argues that the answer to extensive, economy-battering lockdowns cannot be a completely laissez-fair approach, which he said would lead to “horrific” numbers of hospitalizations and deaths.
an alternative, he said, is to implement containment measures early in the epidemic, all but stopping spread, and then opening up society. in various ways, that’s what has happened in many of the most successful covid-fighting countries, such as australia, new zealand, taiwan, singapore, south korea and china.
advertisement
a recent german modeling paper suggests governments need to use lockdowns or other methods to initially push case numbers much lower, to no more than 10 per million people daily. that would allow testing, contact tracing, isolation and moderate social distancing to control the epidemic, and let life proceed more or less normally, the study says.
canada has instead seen a series of lockdowns imposed, often with cases shrinking somewhat, then steadily rebounding when restrictions were lifted.
fatigue with that situation seems to only be growing, even among some health professionals. there’s been too little attention paid to the health impact of “blunt, sweeping” containment tactics, charges toronto family physician sonia malhotra in a commentary on the healthydebate.ca website.
“this is not to deny the terrible health outcomes of covid-19 infections,” she says. “among my patients, however, the acute challenges created by lockdowns are much more apparent.”
share story
