[This is Fred. G’s out and I don’t know where. He posted a blog on the 16th, you know the one; then jumped up, walked out, slammed the door and disappeared. Nobody has seen him since then. Now, I know he had a hard time with the last blog. Not with the writing of it, which was the easy part, but with the simple act of publishing. For two days somebody or something blocked him from WordPress, burying his browser window in dozens of adverts and warnings, each of which required different and progressively more subtle techniques to disable.

The chief culprit may have been something called Supra Savings, which industriously churned up dozens of notices and offers anytime he tried to login to anything. At one point G lost the ability to connect to WordPress, or, for that matter, to any other blog-related web host. [He thought about moving our site to Tumblr if that would help.] Nevertheless, after hours of fussing and muttering he developed some workarounds, published the last blog and, as noted, disappeared.

On the way out he was heard to mutter, The flea, though he kill none, he does all the harm he can.”[1] I believe he was talking about computer hackers and internet attacks, not our blog, but for now you can take it either way. I’ll get a clarification the next time he shows up.]

Anyway, while G has abandoned Ebola for the moment, there remain useful questions to be asked and answered. For example, how fast is the epidemic spreading? The CDC announced that as of October 24, there are 10,141 reported cases of Ebola in West Africa and 5692 deaths.[2] These are government numbers, more or less, originated by the ministries of health of the affected countries, run through the World Health Organization, and repeated by CDC.

The numbers are suspect, of course; many feel that, due to the turmoil in the affected countries caused in no small part by the Ebola outbreak, local governments in West Africa lack the resources to do an accurate tally of the sick and dying.[3] The actual figures, some say, may be up to 2.5 times greater than the ones reported by local governments.[4] How do we get to the truth of these allegations? Who knows? Perhaps the best way would be for someone to fund an independent effort to go in country and actually do a case/body count.

The Ebola outbreak seems to have shifted to major metropolitan areas in West Africa, so would that make it any easier to survey the damage? Disease detectives could focus on known urban areas rather than search the countryside for unknown (and possibly deserted) rural villages. Actually I don’t know the answer to my question, but I’m sure our Government, or the U.N., could find experts and consultants to design a survey and do the job.

Anyway, the picture is bad enough if we just assume the “official” figures are correct. If you recall, a few weeks ago G created a couple of “cheat sheets” to depict where we are vis-a-vis the spread of Ebola. The first one relied on science and experiments reported in late August[5], or more specifically, on observations that Ebola cases at that time seemed to be doubling every 34.8 days. G took August 17 as a starting point, largely because there was a more or less firm case estimate for that date, and charted what would happen if the reported trend continued indefinitely.

There was nothing magic about what G did. He didn’t even make a forecast. He simply said that, if Ebola cases continued to double every 35 or so days, we can expect to see x cases on one date, and twice that number on the next. Now, he said, let’s wait to see what actually happens. Well, fresh results are in for October. G’s model suggested that we would see a total of 8,960 cases by October 26. In point of fact, WHO/CDC are reporting 10,141 cases as of October 24. That’s pretty close, wouldn’t you say?

Will the trend continue? Only time will tell. G’s original projection called for 17,920 Ebola cases by November 30. That’s of course twice the number he estimated for October 26. Now that there are actual figures for October, he might want to adjust the projection for November 30 to, say, 20,282 cases.

“That’s all very fine,” you might say, “but what about the worst case scenario CDC publicized a few weeks ago? You know, the one that said there might be 1.4 million Ebola cases by the end of January next year? [6] How does that stack up against the current numbers?”

Well, I don’t mean to oversimplify, but the basic differences between G’s model and the CDC “worst case” scenario are (i) CDC assumes that cases will double every 20 days rather than every 35; and (ii) CDC believes that official figures grossly under-count actual cases. CDC adjusts for the under-counting by multiplying the official numbers by 2.5.

G did a spreadsheet a while back to see what CDC’s actual projections for given dates might be. It shows 42,000 Ebola cases by October 20, and 84,000 by November 9. Those numbers far exceed anything being reported today.[7]

Of course, there’s also a basic similarity between G’s back-of-the envelope calculations and CDC’s “worst case” scenario. They both chart geometric [aka an exponential] growth in Ebola cases.[8] Unless the trend is interrupted, more and more people will be sucked into the Ebola tornado, and that disease will become a world-wide problem.

As someone once said, we all breathe the same air[9], so we need to look out for one another.

 

 

[1] This is generally attributed to John Donne, and English poet who lived from 1572 – 1631.  You can find it in IZ Quotes, at http://izquotes.com/quote/372047

[2] You can find current numbers on the CDC website, at http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/index.html CDC also saves its previous updates. You can find them at http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/previous-updates.html

[3] See CDC Newsroom, CDC warns Ebola epidemic in West Africa is outpacing current response (September 2, 2014), available at http://www.cdc.gov/media/releases/2014/p0902-ebola-epidemic.html : “The official case count and death toll in the current outbreak exceeds cases and deaths from all previous Ebola outbreaks combined. Yet these official numbers greatly underestimate the actual numbers of cases and deaths and do not adequately describe the outbreak’s toll in human lives, health care and societal disruption, and economic loss.”

[4] See CDC, Meltzer, et al., Estimating the Future Number of Cases in the Ebola Epidemic — Liberia and Sierra Leone, 2014–2015 (September 26, 2014), at the Abstract, available at http://www.cdc.gov/mmwr/preview/mmwrhtml/su6303a1.htm : “To aid in planning for additional disease-control efforts, CDC constructed a modeling tool called Ebola Response to provide estimates of the potential number of future cases. If trends continue without scale-up of effective interventions, by September 30, 2014, Sierra Leone and Liberia will have a total of approximately 8,000 Ebola cases. A potential underreporting correction factor of 2.5 also was calculated. Using this correction factor, the model estimates that approximately 21,000 total cases will have occurred in Liberia and Sierra Leone by September 30, 2014.”

[5] See Sciencexpress Reports, Gire et al., Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak (28 August 2014) (hereafter cited as Genomic Surveillance at __), available at http://www.sciencemag.org/content/early/2014/08/27/science.1259657.full.pdf

[6] See The Washington Post, Sun et al., CDC: Ebola could infect 1.4 million in Liberia and Sierra Leone by end of January (September 23, 2014), available at:   http://www.washingtonpost.com/national/health-science/cdc-ebola-could-infect-14-million-in-west-africa-by-end-of-january-if-trends-continue/2014/09/23/fc260920-4317-11e4-9a15-137aa0153527_story.html

[7] Of course, CDC inflates official numbers by a factor of 2.5 to compensate for local government “undercounting.” If you take out the inflation, that leaves you with a CDC estimate of 16,800 reported cases for October 20 and 33,600 cases for November 9. Even these adjusted figures are far above anything now being counted in West Africa.

[8] Just using G’s figures, by September 25, 2016 Ebola cases would substantially exceed the population of Planet Earth. The same thing would happen under CDC’s “worst case” scenario, only sooner. For those of you who are interested, our spreadsheets are available upon request.

[9] The original quote’s from John Kennedy [the President], by the way. “Our most basic common link is that we all inhabit this planet. We all breathe the same air. We all cherish our children’s future. And we are all mortal.” You can find it at brainyquote, at http://www.brainyquote.com/quotes/quotes/j/johnfkenn132358.html#p8TEOX4zsqz74PS7.99

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