Intended for healthcare professionals


Covid-19: Experts debate merits of lockdowns versus “focused protection”

BMJ 2020; 371 doi: (Published 03 November 2020) Cite this as: BMJ 2020;371:m4263

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  1. Jeanne Lenzer
  1. New York, USA

Three experts with widely differing viewpoints regarding appropriate public health measures to control the spread of covid-19 weighed in on lockdowns during a debate1 sponsored by Johns Hopkins University.

The experts represented viewpoints ranging from advocacy for “focused protection” as described in the Great Barrington Declaration2 to recommendations for population-wide mandates as described in the John Snow Memorandum.3

David Dowdy, associate professor of epidemiology at Johns Hopkins School of Public Health, said he agreed with “much of the content” of the memorandum, which states that broad lockdowns were initially necessary to “reduce mortality and to prevent healthcare services from being overwhelmed” but that the focus should shift to detecting localised outbreaks through a “comprehensive find, test, trace, isolate, and support system” approach once low levels of covid-19 are attained.

Dowdy cited Australia’s approach of increased testing to determine where transmission is occurring and then focusing interventions on local geographic areas (for example, postal codes) where transmission is going up. But Dowdy said he declined to sign the memorandum, which was signed by thousands of doctors worldwide, because he was concerned that it could “implicitly shame” doctors with differing viewpoints and make some fearful of speaking out.

Jay Bhattacharya, professor of medicine at Stanford University and a health economist who co-authored the Great Barrington Declaration, said the vastly differing mortality risk rates based on age and co-morbidities and other factors could allow “focused protection” for those at risk while allowing children to go to school and younger adults to continue working.

Citing seroprevalence data4 published by the World Health Organization, Bhattacharya said that covid-19 has an infection survival rate of 95% for people 70 years and older. While he described 5% mortality among the elderly as a “severe problem,” he pointed out that the survival rate for people under 70 is orders of magnitude better at 99.95%.

Bhattacharya added that broad lockdowns can paradoxically increase harms to the elderly as economic displacement induced by lockdowns leads young adults to live with older parents. A benefit of focused protection, he told The BMJ, is that resources could be redirected from low yield interventions to where supports are most needed.

Stefan Baral, an infectious disease epidemiologist at Johns Hopkins School of Public Health, said he supported adaptive interventions to protect at-risk people rather than broad lockdowns of entire populations. He said his mother lives in Sweden and “there’s nowhere else I would have wanted my mom to be. I love my mom and I feel she’s safe there.”

But Baral said that simply opening up society in the US isn’t sufficient unless, and until, support is in place for at-risk people. “Testing is just data, it’s not an intervention,” he said. “If you’re poor and told to test and isolate if positive, without measures in place to pay that person’s wages and to pay for a hotel room if they can’t isolate at home, testing is meaningless, leaving many people to face impossible choices. ”

Baral called for “resources before restrictions,” saying the current approach in the US is “good for rich folk” who can isolate, work from home, and have food delivered. He said, “We’re asking people already on the economic margins to absorb social costs,” which is worsening already existing inequalities and suffering.

Herd immunity and the true measure of success

When the moderator suggested that the Great Barrington Declaration recommended herd immunity as a strategy, Bhattacharya explained that he and his colleagues don’t see herd immunity as a strategy but as a simple “biological fact,” adding, “It will eventually happen. That’s how epidemics end. So, the only question is how you get there with the least amount of human misery, death, and harm.” The best way, he said, is to “acknowledge who actually is in danger and devote enormous creativity, resources, and energy to protect them.”

There appeared to be some consensus among the panellists that the measure of successful public health interventions can’t solely rest with death counts from covid-19. The downstream harms of lockdowns must be considered in the benefit-to-harm calculus of various forms of lockdown.

Bhattacharya cited an estimate from the United Nations World Food Program indicating that pandemic lockdowns causing breaks in the food chain are expected to push 135 million people into severe hunger and starvation by the end of this year. Other harms include the difficult to measure effects of missed schooling for many children.

Another area of consensus was that broad lockdowns are to be avoided. Differences remained among the experts about how best to go about more focused lockdowns as countries face second and third waves of covid-19, but they expressed their hope that this initial dialogue will be the beginning of many more respectful and evidence based discussions.