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The bell curve of pandemics may be good news for coronavirus concerns

This was news to me when I read it this morning, so I figured some of our readers might not have heard of it yet either. The subject at hand is how long it will take the coronavirus outbreak to run its course and fade from the pages of history. We’ve been hearing all sorts of estimates ranging from end of the world scenarios to “no big thing,” without much common consensus to be found. But Michael Fumento at the NY Post calls our attention to something called Farr’s Law which suggests that it all may be over sooner than some are currently predicting.

China is the origin of the virus and still accounts for over 80 percent of cases and deaths. But its cases peaked and began ­declining more than a month ago, according to data presented by the Canadian epidemiologist who spearheaded the World Health Organization’s coronavirus mission to China. Fewer than 200 new cases are reported daily, down from a peak of 4,000.

Subsequent countries will follow this same pattern, in what’s called Farr’s Law. First formulated in 1840 and ignored in ­every epidemic hysteria since, the law states that epidemics tend to rise and fall in a roughly symmetrical pattern or bell-shaped curve. AIDS, SARS, Ebola — they all followed that pattern. So does seasonal flu each year.

The full name is Farr’s Law of Epidemics and, as Fumento points out, it’s been around since 1840, accurately predicting the rise and fall of various epidemics including AIDS, SARS and Ebola. This theory describes a pattern that makes quite a bit of sense when you stop to think about it. The spread of any successful contagion should work out to something resembling a normal bell curve over a given period of time.

When a new contagion first emerges, it’s going to be located in one specific location and only impact a few people. It will take time for it to really get any legs as those people mix with others and begin traveling. But after the numbers reach a point of critical mass, the transmission rates rise exponentially, approaching some peak point. After that, the contagion will either begin killing off its hosts in large numbers, slowing the spread, or people will survive and develop their own immunity, similarly cutting down on new cases. That produces a plunge in transmission rates until only small pockets of unaffected people are at risk. Thus the bell curve.

According to the CDC’s numbers, combined with what the Chinese are reporting (your periodic reminder to take anything put out by the Chinese Communist Party with a grain of salt), the spread of the coronavirus in that country started off with only a few patients but rose to a high of 4,000 new cases per day in less than two months. But since that time, it’s already dropped back down to roughly 200 new cases per day, once again following the bell curve pattern.

If the spread of the virus plays out that way in the United States (and we still seem to be on the upward slope), transmission rates could peak next month and then fall to small, more manageable levels by May or June.

The only point I would quibble with Fumento over is his references to the mortality rates. He repeats the frequently cited fact that the flu has killed far more people than the coronavirus during the same period. It’s at least a 100 to 1 ratio. That’s true, but as any number of doctors have noted, that’s because so many more people get the flu every year, with numbers in the tens of millions. The actual mortality rate for the flu is 0.1 percent, with most of those deaths taking the elderly and those with compromised immune and/or respiratory systems.

The mortality rate for the coronavirus isn’t pinned down yet, but it appears to be closer to two percent. Still small, but 20 times higher than the flue. But those numbers aren’t solid either because nearly everyone seems to agree that up to 80% of people are experiencing symptoms so mild that they don’t bother going to the doctor or getting tested. The total number of carriers is still totally unknown.

In any event, I’m choosing to take this Farr’s Law concept as good news and a hopeful sign. But I’ll probably still stay off of airplanes for a couple of months if at all possible.