“Suppression and Mitigation Strategies for Control of Covid19 in New Zealand”
It’s a paper linked to by a news source I’ve never read before, “The Spinoff,” but it caught my attention because I know one of the authors, Mike Plank, from the whitewater kayak club. He’s a math professor at the University of Canterbury, and a member of the organization called “Centre for Complex Systems and Networks, which has been doing some epidemic modeling for the NZ government.
The math paper was my Delight of the Day…which might tell you something about how the rest of the day went. But I was really quite impressed with the clarity of the “executive statements” (the main points) of the paper. Mathematicians don’t sugar coat things.
Basically, without a vaccine, the way the epidemic ends is that enough of us get the infection (and the subsequent immunity to re-infection) that the transmission rate slows to less than new person getting sick from every infected person (because infected people are surrounded by mostly immune people), and the disease dies out. An optimist might note that if the infection rate stays below 1 for any reason for long enough, the disease eventually dies out….doesn’t technically have to be herd immunity. Wash those hands!
“Suppression” (meaning social distancing, quarantines, closed businesses….what we’re doing now) can only delay an epidemic, not prevent it. When control measures are relaxed, the subsequent spike in infections is just as high and steep….just as overwhelming to the health care system.
“Mitigation” means slowing down the epidemic so that at any given time there are enough hospital beds for all the people who need them. It entails letting the control measures up just slightly so the infection progresses, then clamping down again, repeating that cycle again and again. That graph, with numbers run for NZ (500 ICU beds in NZ, and a host of other assumptions around transmission rate and hospitalization rate), extended out to 2022. Two and a half years.
There’s a gem of a quote near the end of the paper. Paraphrased: “The only other countries that have so far succeeded in getting transmission low enough for mitigation to work are China and South Korea, using extremely intensive measures, including electronic surveillance of their citizens. No western democracy has yet succeeded in reducing their transmission low enough to slow down their epidemic.”
So, I’m not sure what the end game is with all our social distancing. Two years is an awfully long time.