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2.4.20

LA virus testing, death data don't add up

With little attention or fanfare, this week Democrat Gov. John Bel Edwards extended a series of proclamations limiting gatherings and commercial activity to stave off the Wuhan coronavirus pandemic. He did this using data that appears increasingly questionable.

Observers such as MacAoidh already have pointed out not only errors in data collection that affect perceptions about the disease’s contagion in Louisiana, but also have noted timing involved in releasing specific numbers on specific days fits a pattern designed to produce messaging that promotes a political agenda. Certainly, continuation of the Edwards bans throughout the entire state idles further a Legislature chomping at the bit to enact policy contrary to Edwards’ liking while it embolden actions comporting to his general philosophy of expanding government through increased taxation and spending.

The extension again raises the question of whether a blanket approach serves the state’s best interest. The figures for today continue to show the virus, at least in a critical form, remains largely a New Orleans-area phenomenon. Orleans, Jefferson, and their surrounding St. Tammany, St. Bernard, Plaquemines, LaFourche, and St. Charles Parishes have but 28 percent of the state’s population but 69 percent of the cases and 73 percent of the deaths.

If you can trust these numbers. Whether through shoddiness or deliberate manipulation, it has become obvious some reported numbers strain credulity, if not make no sense at all. It begins with deaths.

The introduction of the virus came in Washington, first in Snohomish then King Counties. With its initial appearance and particularly in a convalescence hospital, King has a high death rate from infection, at 6.64 percent as of yesterday. With King having a third of the state’s population, this has driven the statewide rate to 4.13 percent. That’s higher than the rate in Orleans as of today at 3.97 percent, and statewide of 3.39 percent.

The area surrounding New York City (itself comprised of five counties often known by their borough names) – Nassau and Suffolk Counties on Long Island, Westchester and Rockland Counties to the north on each side of the Hudson River, and the New Jersey counties across the Staten Island Sound of Bergen, Passaic, Hudson, Essex, Union, Middlesex, Monmouth, and Ocean City, with the city since have become the cockpit of the virus. But within this area of about 18 million people, which contains just under half of all U.S. cases and four-ninths of its deaths, it has a death rate only half that of Orleans.

And deaths per capita tell an even more extreme story. Consider that King and its suburb Snohomish have registered 203 deaths among their more than 3 million residents, just five more than Orleans and Jefferson that have just over 800,000 people. King has 75 deaths per million from the disease, while the New York City area has registered 111 per million.

Yet, stunningly, Jefferson rings up a death per capita figure more than twice King’s, at 168 per million, and Orleans a number almost three times that of the New York City area at 320 per million. This likely is the highest such statistic among large metropolitan counties in the U.S. – but not the highest in Louisiana, where upriver St. John the Baptist Parish data compute to an amazing 322 per million.

Throw in the parishes surrounding Orleans and Jefferson and the parish upriver from St. John the Baptist (which itself is just upriver from St. Charles), Ascension, with those six together having a rate of 58 per million, and it becomes clear why Louisiana has a statewide rate of 67 per million. Not only is this double Washington’s, it’s higher than all of New Jersey and trails only New York’s 121, supercharged by New York City’s number of 161.

Only two things can explain why Louisiana has a death rate per capita from this malady far exceeding the national average of 13.8 per million: something about its people and/or health care system makes Louisianans much more likely to die from this disease, and/or the state reports deaths in a way that inflates the cause being the virus.

Then there’s the testing numbers, which, in two words, are entirely unreliable. According to state data, Louisiana in aggregate has had just over 51,000 tests performed, representing 1.1 percent of the population. This is midway between the Washington figure of 1.02 percent and New York’s 1.22 percent, although well above New Jersey’s 0.66 percent. Positive tests registered in Louisiana about 18 percent of the time, as opposed to 8 percent in Washington (which had an aggressive program from the start), New York’s 38 percent, and New Jersey’s 43 percent (both of which, like Louisiana, started relatively late).

But the proportions vary widely among parishes, and in many cases this seems likely a consequence of counting error. For one thing, as of today the individual parish totals didn’t add up to the state numbers. State statistics showed 3,901 conducted by the state and 47,185 by commercial entities. Yet the sum of parish totals had 280 fewer from the state and 447 fewer done by private labs.

Worse, some parish numbers seemed unlikely. St. John the Baptist, with its infection rate of 1:159 not much higher than Orleans’ 1:124 (which is the highest in the nation outside of the sub-100 numbers from Rockland and Westchester Counties in New York), had its 274 cases identified from just 25 tests – a mathematical impossibility unless commercial testers reported from their location and not the parish of residence of the person tested, if that person sought a test from outside his home parish. Four other parishes had more cases than tests, or close to that.

In other instances, the sheer volume and tests and proportions positive raise eyebrow. Jefferson has rung up 2,178 positives from just 3,077 tests. Again, maybe along with St. John residents they are running to Orleans to have their testing done (over 23 percent of tests done there have turned out positive), but that makes for some weird dynamics: why would testing facilities in Jefferson disproportionately attract people with it and/or have those residents without it have their testing done elsewhere?

And if that’s how it works, categorizing in this fashion doesn’t do a whole lot to produce data useful for decision-making about the pandemic. For example, in a radio interview Edwards implied a rapidly climbing number of cases popping up in Caddo and Bossier Parishes meant these citizens didn’t behave carefully enough, but that doesn’t square with the two having more testing done by far than any single parish except for Orleans and a relatively miniscule positive rate a quarter of Orleans.’

In today’s news release about the most recent numbers (which apparently skewed upwards because previously unreported cases from days ago finally made it into the official tally,” Edwards noted that “I have said time and again – COVID-19 is a statewide problem and testing is a vital step towards understanding the scale of this problem.” In reality, it mostly is a New Orleans area problem, and the way testing data is presented confuses rather than clarifies the scale of the problem.

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