Thread by @RARohde

Years from now, I am sure many histories will be written about COVID-19 and the diversity of government responses to it.

What worked, what didn't, what the costs and consequences were, etc.

In the moment, it is hard to judge, though multiple approaches are evident.

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What's already clear is that some governments, e.g. China, South Korea, Singapore, are aiming for total suppression.

In other words, they want to find every case, isolate every sick person, tightly control the borders, and completely eliminate COVID-19's local spread.

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Early results for China and South Korea suggest that suppression may be possible, though it requires a massive investment in testing and contact tracing.

https://twitter.com/RARohde/status/1241117770479218688

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Suppression also means strict border security and creating robust surveillance networks capable of catching any new outbreaks early.

For example, by requiring temperature checks at transit hubs, schools, malls, and other public spaces.

Image: CNN

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If achieved, suppression would prevent most members of a society from ever getting sick.

In which case, you avoid many deaths and much of the impact on hospitals. Depending on how long it takes to suppress the virus, the social and economic disruption might also be reduced.

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However, until there is a vaccine or other effective treatment, suppression focused countries would have to maintain surveillance and controls indefinitely, likely for years.

Every new outbreak would have to be located quickly and eliminated vigorously.

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As an instinctively fearful human, suppression seems highly appealing.

However, I am ill-equipped to know if it is the optimal public policy. For many countries, especially poor ones, suppression may simply not be achievable.

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Right now, most countries appear to be aiming to merely slow the spread of COVID-19, i.e. #FlattenTheCurve, without any aspiration of eliminating domestic transmission.

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The hope is that mitigation options slow COVID-19 enough to make the impact manageable, without overwhelming healthcare resources.

However, this still allows most of a country's population to eventually be infected, and a significant number would die.

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In addition, mitigation-only strategies can only reduce the burden so much. It may still be necessary to greatly increase hospital capacity (pink horizontal line) or still risk being overwhelmed.

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Image: imperial.ac.uk/media/imperial…

To the extent that mitigation may require long-lasting social and movement restrictions, the economic disruption could actually be amplified.

And we are already talking about trillion dollar support packages.

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However, if the virus is going to infect most of the population, then at least one can hope that it conveys a long-lasting immunity, which would prevent future outbreaks of the same virus.

It is currently unknown how long COVID-19 immunity will typically last.

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Honestly, at this point, mitigation without suppression feels like a half-measure with few apparent benefits.

It is plausible to imagine mitigation focused countries suffering both larger health and economic costs than countries that successfully suppress the virus.

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History and public opinion will judge countries harshly if a poorly managed COVID-19 response results in a disproportionate health and economic impacts compared to other similar countries.

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Ultimately though, public health experts in each country will have to decide the best course of action, managing economic and health impacts within the limits of what is still practically achievable for them.

However, I hope they think hard about South Korea's example.

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