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8.4.20

Edwards chose higher-cost way to flatten curve

The good news is Louisiana maybe has entered the downhill portion past the worst of the health crisis. The bad news is that policy decisions will make that stretch longer and more painful than it could have been.

Yesterday, at what has become typical afternoon news conferences concerning the Wuhan coronavirus pandemic, Democrat Gov. John Bel Edwards sounded more upbeat about the state’s prospects. He proclaimed that, in part due to what he alleged was the nation’s highest rate of testing and to social distancing measures (many of which come imposed courtesy of a series of proclamations he has made utilizing emergency powers), the rate of infection seemed to be tailing off, or “flattening the curve.” He recommended staying the course, continuing such measures and his proclamations to encourage these through their targeted expiration date of Apr. 30.

He was wrong about the testing data. Actually, as of that time (and as of today as well), Louisiana ranked second per capita in the country, at 1.61 percent of the population tested, to New York’s 1.75 percent. The Empire State continues to lead Louisiana in deaths per million, 322 to 140, and in infection ratio of 1:130 to 1:273 (Louisiana also has started to trail New Jersey in both categories as well).

Edwards has proven correct on the decreasing rate of increase of cases – but in a rather discouraging way. Of the states with the highest recent growth rates, all have seen a decrease as of yesterday in the 5-day moving average, Louisiana included. Unfortunately, while every other state showed a significant single-digit dip, Louisiana’s barely moved lower, just 0.3 percent.

This continues the pattern where Louisiana’s rates of infection and death have slowed more shallowly and later than other states’. Keep in mind the comparison to Washington, which began working on testing capacity even before the first U.S. case was discovered (there, as it turned out) and was ready to go when the federal government in late February gave the green light to have labs other than itself start that so it could identify quickly and isolate suspected cases. It didn’t experience its 100th case until Day 8 (starting the clock on its cases on Feb. 28, counting the previous eight that had occurred sporadically since mid-January on that day), the same day Louisiana hit that mark.

But afterwards was a different statistical story. Edwards didn’t bring the state lab nor hospitals, including the partner charity hospitals, together prior to the first case to increase capacity. So, whereas Washington caught and isolated cases relatively quickly and early, with little testing capacity Louisiana couldn’t. Through that Day 8, Washington (which has about 160 percent of Louisiana’s population) had conducted over 1,600 tests while by that day Louisiana had done fewer than a fifth of that number. So, while by Day 14 the rolling seven-day average for Washington of new cases was 21 percent, for Louisiana it was 34 percent, and the gap has persisted although still diminishing.

The benefits of flattening the curve depend very much on its amplitude (the distance between zero and the mode –or high point – in a largely symmetrical unimodal curve – one with a single peak) and curvature. Over the same time span, the higher the amplitude, the more flattening must occur (because, in mathematical terms, the area beneath the curve is larger, representing in this instance more cases or deaths). But if assuming the same area, flattening then doesn’t change the number or deaths or cases, just their timing. In other words, strategies to flatten the curve also prolong its duration, posing the policy decision of whether to let it burn quickly (creating a higher amplitude).

Burning quickly, so to speak, would have meant nuanced, targeted measures that upon detecting an outbreak then clamping down highly restrictively immediately to protect vulnerable populations, while letting as-yet unaffected areas to conduct business as usual until an outbreak was detected there. Moreover, the clampdowns would have created conditions to isolate only the vulnerable and let others – typically younger without existing serious health issues – go about their days with fewer restrictions. This would let the virus burn through the healthy population quickly, building “herd immunity” that ultimately would allow the vulnerable to eschew isolation more rapidly.

Edwards didn’t do that. Instead, he belatedly launched that series of proclamations gradually tightening restrictions indiscriminately across cohorts and geographies. That will make the disease burn less brightly but for longer. If you flatten a curve at the top, its amplitude may be lower but its area doesn’t change so it creates longer tails.

So, while we are seeing the curve in Louisiana flatten, because of policy decisions by Edwards it will take longer and leave the vulnerable in danger for a greater period. It will delay reopening the state for normal business, which is disastrous for the state ranked, in two separate studies, 44th and 50th best able to handle the economic fallout of the pandemic.

At that briefing, Edwards was wrong about one thing, barely correct about another, but regardless it all added up to a dose of dim optimism as Louisiana struggles to fight off this virus.

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