{"id":8613,"date":"2020-03-28T12:14:53","date_gmt":"2020-03-28T17:14:53","guid":{"rendered":"http:\/\/richard.rathe.org\/?p=8613"},"modified":"2020-03-29T10:43:54","modified_gmt":"2020-03-29T15:43:54","slug":"the-us-covid19-pandemic-and-s-curves","status":"publish","type":"post","link":"https:\/\/redmangrove.org\/rathe.org\/richard\/2020\/the-us-covid19-pandemic-and-s-curves","title":{"rendered":"The US COVID19 Pandemic and S-Curves"},"content":{"rendered":"\n

Around March 25 the US became the poster child for the COVID19 Pandemic<\/strong>. This graphic from the Financial Times Tracking Site<\/a> tells the sad tale. America is again number one! =(<\/p>\n\n\n\n

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source:ft.com
<\/figcaption><\/figure>\n\n\n\n

Note that when I first blogged about COVID19 back on March 1st<\/a> there were only 62 reported cases in the US!<\/p>\n\n\n\n

At the time I’m writing this, the State of Florida<\/strong> is just getting around to effective measures. The official count is currently only 2,900 cases but that is certainly off by a factor of ten or more!<\/strong> (In the US we’ve done an appalling job<\/em> <\/em><\/strong>of testing for and controlling exposure to infected people.)<\/em><\/p>\n\n\n\n

This graphic appeared on Twitter yesterday…<\/p>\n\n\n\n

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It got me thinking… wouldn’t it be more effective it it were inverted?<\/em> So I gave it a shot…<\/p>\n\n\n\n

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Doesn’t that look more intimidating?! Imagine the longest, steepest rollercoaster<\/strong> you’ve ever been on, or maybe falling off a cliff<\/strong>. (You’ll notice I also added an arrow<\/strong> to emphasize there is currently NO BOTTOM <\/strong>to this curve!)<\/p>\n\n\n\n

S-Curves<\/h4>\n\n\n\n

This put me in mind of basic epidemiology<\/strong> from medical school and even well-taught high school biology. Every Epi textbook has a graphic that looks something like this…<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

This is the classic “s-curve<\/strong>” of epidemic spread. Things start slowly, but quickly speed up due to exponential growth<\/strong>. Our trajectory in the first graphic is DOUBLING every 2-3 days!<\/strong><\/p>\n\n\n\n

At some point the curve flattens<\/strong> because public health efforts are working–or all potential hosts are either infected or dead!!<\/em> The curve for China<\/strong> in the second graph is roughly s-shaped and they’ve successfully made it to the leveling off phase (for now).<\/p>\n\n\n\n

Some States are doing a better job at flattening the curve<\/strong> through common sense public health efforts. Compare the dark bars in this graphic. [Larger Version]<\/a> Kentucky<\/strong> (blue) took more aggressive steps earlier. Contrast this with Tennessee<\/strong> (orange), which by March 20th had over four times<\/strong> more confirmed cases!<\/p>\n\n\n\n

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source:twitter.com<\/figcaption><\/figure>\n\n\n\n

That brings us to TESTING<\/strong> for the virus. The classic curve informs who we should test and when. Early testing helps identify individuals with the virus so they can be isolated<\/strong> from the population at large. (Remember, many of these people are not obviously sick.<\/em>) This is referred to as the Containment Phase<\/strong>. In the US we did not\/could not do adequate proactive testing due to a cascade of technical, regulatory, and political missteps<\/strong>. [Link to More Info]<\/a><\/p>\n\n\n\n

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Failure to test<\/strong> enough of the right people early lead us to where we are now, Epidemic Spread<\/strong>. No one knows how far we will progress before the curve starts leveling off. This is a scary place to be, a bit like looking over a cliff edge into the abyss.<\/em> The focus of testing is now on those who are ill, first responders, and healthcare workers at all levels.<\/p>\n\n\n\n

Once we reach the point where the total number of new cases begins to drop<\/strong>, testing again becomes important to ensure containment, identify people who can go back to work, etc… This will also be the time to start a different sort of testing (for antibodies) to gauge who is immune<\/strong>, and who remains susceptible to new infection.<\/p>\n\n\n\n

Epidemiologist’s Worst Nightmare<\/h4>\n\n\n\n

To help illustrate how the US Epidemic<\/strong> spread I’ll link to this fascinating video<\/a> from a data visualization company. They started with anonymous cell phone “ping” data from a small segment of beach in Fort Lauderdale during <\/em>Spring Break<\/em><\/strong>.<\/em> <\/p>\n\n\n\n

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source:youtube.com

<\/figcaption><\/figure>\n\n\n\n

As these few hundred individuals<\/strong> took themselves (and their phones) back home, look at the result (called a Heat Map<\/strong>)!<\/p>\n\n\n\n

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source:youtube.com<\/figcaption><\/figure>\n\n\n\n

This is an epidemiologist’s worst nightmare!<\/strong> A similar scenario could be expected from this year’s Mardi Gras<\/strong>. The Governors of Florida and Louisiana should both be held accountable for not closing these infection pipelines down!<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Around March 25 the US became the poster child for the COVID19 Pandemic. This graphic from the Financial Times Tracking Site tells the sad tale. America is again number one! =( Note that when I first blogged about COVID19 back on March 1st there were only 62 reported cases in the US! At the time … Continue reading “The US COVID19 Pandemic and S-Curves”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[129,22,28],"tags":[468,469,466,473,475,467,474],"class_list":["post-8613","post","type-post","status-publish","format-standard","hentry","category-commentary","category-medicine","category-science","tag-coronavirus","tag-covid19","tag-epidemic","tag-epidemiology","tag-florida","tag-pandemic","tag-united-states"],"_links":{"self":[{"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/posts\/8613","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/comments?post=8613"}],"version-history":[{"count":41,"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/posts\/8613\/revisions"}],"predecessor-version":[{"id":8668,"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/posts\/8613\/revisions\/8668"}],"wp:attachment":[{"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/media?parent=8613"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/categories?post=8613"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/redmangrove.org\/rathe.org\/richard\/wp-json\/wp\/v2\/tags?post=8613"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}