10 May 2020 – Sunday – #56

Wow, I slept a lot last night. Like ten hours. It must be because I’m walking 10,000 steps again. I remember waking up to an intense rain storm, but that’s all. Then back to snoozeland. The weather in Barcelona reminds me of the weather in San Francisco because of the proximity to the sea. But the rain storms here are something else. Anyway, I usually start writing around 10a, but I didn’t get out of bed until 10:30a. So, hang on, here I go!

As I was emailing Janet this morning about masks, I remembered that when I started Covid Diary BCN, I posted about Covid-19 decontamination protocols. Back then, no one knew. It made sense to wipe down every new surface entering the house with bleach or blast it with UV because, well, it was the most comprehensive advice at the time. It made sense to shower and put on clean clothes after each outing. It made sense to microwave any to-go food. More is better. Better safe than sorry.

Narratives change with new information. Surfaces aren’t as dangerous as we thought. Long periods of time in enclosed spaces with others is more dangerous than we thought.

My Covid-10 decontamination these days is to quarantine every package or item coming into the house on the back patio or in a separate refrigerator for 1-2 days, and then wash my hands. It takes a minute or two. And if I want something right away, I don’t worry about it. Last week I didn’t microwave the pizza I brought home and I didn’t quarantine the box. My decontamination ritual evolved as the Covid-19 narratives change.

Today I want to look at some other narratives that are changing. One is the herd immunity narrative. The common narrative that I have repeated in Covid Diary BCN is that if 60% of the population has immunity, the population has reached the point where there won’t be additional crippling outbreaks of a disease like Covid-19.

The 60% number for herd immunity is like Pareto’s principle, or the 80-20 rule, that says, for instance, 20% of your customers buy 80% of your products. Pareto’s principle isn’t strictly 20% or 80%, but people know that you’re referring to a particular statistical distribution shape when you just say the words “80-20 rule.”

The same way it’s important to question whether it’s 20% of your customers buying 80% of your products or 5% buying 95%, it’s important dig a little deeper on the 60% herd immunity. Here there may be some good news about Covid-19 herd immunity.

Although estimates vary, it is currently believed that herd immunity to SARS-CoV-2 requires 60-70% of the population to be immune. Here we show that variation in susceptibility or exposure to infection can reduce these estimates.

M Gabriella M Gomes, et al., “Individual variation in susceptibility or exposure to SARS-CoV-2 lowers the herd immunity threshold,” 27 April 2020

Researchers suggest that since susceptibility to Covid-19 isn’t homogeneous across the population, that the 60% rule for herd immunity may apply to the susceptible subset of the population rather than the entire population. If the susceptible subset of the population is infected more early on, then it’s possible that the infection rate for overall herd immunity may be less than the commonly assumed 60%.

So, maybe our 60% herd immunity narrative will change soon. How about my narrative that Covid-19 is going to break supply chains?

I’ve asserted that the Covid-19 outbreaks at meatpacking plants are the canary in the coal mine for Covid-19 and the supply chain economy, that the way the food supply chain is breaking is a warning about how other supply chains will break. By the way, Covid-19 outbreaks at meatpacking plants are not unique to the US. Covid-19 outbreaks at meatpacking plants happen here in Spain, too. And elsewhere.

It turns out that meatpacking plants have attributes that are conducive to Covid-19 transmission.

Thanks to the magic of Youtube, we can take a look at what goes on inside a (very recently cleaned) meatpacking plant.

Inside a meatpacking plant. OMG, who selected the sound track?

So, let’s see. Enclosed space, lots of ways aerosols could be flying around with saws spewing particles and machines launching animal parts. A low wage, often immigrant labor force with incentives to show up even when they are sick and with minimal access to health care. An industry with a history of outbreaks of other airborne diseases. A White House directive to keep the plants open at any cost. What could go wrong when Covid-19 makes an appearance?

Parenthetically, Shane asked the other day whether I thought meat itself was a medium for Covid-19 transmission. I don’t think it is. The sum total of my evidence is that butchers at meat counters and hamburger flippers at MacDonald’s are not falling over dead at work.

Maybe my canary in the coal mine narrative about meatpacking plants and supply chains is wrong. Maybe other supply chains are less prone to Covid-19 outbreaks. Certainly robotics and Machine Learning are reducing human participation in certain parts of supply chains. For instance, seaports.

Robotics and Machine Learning at Ports of Auckland.

But people are still involved in most supply chain activity even when it’s highly automated. I think the approach with Covid-19 should be development of checklists to help supply chain operators identify and remediate Covid-19 risks. Then, perhaps the meatpacking supply chain can be instructive to other supply chains rather than the first in a series of broken supply chains.

That kind of regulation, however, takes international coordination, something in short supply these days. Which brings me to the final prevailing narrative I want to challenge today. That the government is here to help.

The starkest contrast in government response is Germany, whose chancellor has PhD in quantum chemistry, and the United States, whose president is a failed businessman turned reality TV star. Americans keep thinking the US government is going to help. But why are they clinging to this narrative?

Germany is solving its Covid-19 epidemic with measurements and analysis. The US is solving its Covid-19 with capitalism. Actually, capitalism with a dash of zero-sum reality TV adrenalin.

Trump is the capitalist warrior ready to go back to work at any cost. He is ignoring the country’s mounting Covid-19 death toll (79,696 at this writing) and brushing aside the Covid-19 infections in White House staff and Secret Service. Not enough Covid-19 tests to monitor infection rates? Don’t worry. Profits will solve Covid-19 and put meat on the table!

By the way, those anti-lockdown protests Trump eggs on? It looks like as many as 72 people were infected with Covid-19 at the controversial Wisconsin protest. But profits will solve that, too.

Not that it’s a cakewalk in Germany. Germany relaxed its lockdown about two weeks ago. It’s not a surprise the infections have gone up, but it appears that R = 1.1. That’s the bad news. The good news is that Germany, unlike the US, is testing enough to know its infection rate R > 1. As Chancellor Merkel explained, if R = 1.1 in Germany, the country runs out of hospital resources in October. Germany has some wiggle room to adjust its Covid-19 policies.

If there’s a country to beat for Covid-19 reponse, it’s South Korea. This Twitter thread from an American in Seoul is instructive for understanding the steps South Korea has taken to stop the spread of Covid-19.

Until there’s a treatment, cure, or vaccine, the next step for the world looks like test, track, and quarantine. That’s an easy narrative, but everyone has to be on the same page.

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