Category Archives: Community

Different ways to model a pandemic

Numberphile: The Coronavirus Curve. (YouTube, 22:17min) “Ben Sparks explains (and codes) the so-called SIR Model being used to predict the spread of coronavirus (COVID-19).”

I played along at home and created my own version with Geogebra, but you can also find Ben Sparks’s version here: SIR Model.

Be sure to also check out the links in the description of the video.

3Blue1Brown: Simulating an epidemic. (YouTube, 23:11min)

“While here we looked at what you might call an “agent-based” SIR model, if you want to see what it looks like as a set of differential equations, Ben Sparks just did a lovely video on the topic over at Numberphile [see above].

There are a few reasons I like the agent-based model here, for demo purposes at least. It’s a bit easier to understand for those who are not comfortable yet with ODEs, for one. It also conveys how things are not deterministic; no real-world curve will look as smooth as the differential equations. It also makes it way easier to ask questions and bake other assumptions into the model. Introducing things like travel or community centers into the differential equations would get very hairy very quickly. For those who want to go much more deeply into this, the Institute for Disease Modeling has a lot of models free for people to look at and play with.”

“Look to your backyard and recreate there”

The Washington Post: Thousands are crowding into free national parks. And workers are terrified of coronavirus.. “A park ranger at Grand Canyon National Park had 600 close contacts with visitors in a single day, greatly increasing his exposure to infection, according to a staff member at the attraction.”

“Two days before he cursed a supervisor and quit the National Park Service job he loved, Dustin Stone arrived to work in a foul mood. A decision by Interior Secretary David Bernhardt to keep national park sites open despite the coronavirus outbreak left him angry and in disbelief.
The virus hasn’t reached Skagway, a tiny town on the Alaskan panhandle where Stone lives and worked at the Klondike Gold Rush National Historical Park. But if it does, he said, it could be a disaster. “I’ve lived here year-round through eight flu seasons, and I’ve seen how quickly an infection can spread,” he said. “When one of us gets sick, most of us get sick.” There’s no full-time doctor and no hospital in Skagway. A single community health clinic has a registered nurse and assistants.
[…]
“This is a political game being played with people’s lives by leadership at the highest levels of the Department of Interior, and, I believe, the White House,” Stone said. “President Trump is the one who announced the fee waiver. I don’t think he knows what a national park is. I would be so surprised if Donald Trump ever set foot in a national park.””

Coronavirus: The Hammer and the Dance

Tomas Pueyo: Coronavirus: The Hammer and the Dance. “What the Next 18 Months Can Look Like, if Leaders Buy Us Time”. (March 19, 2020)

Here’s the Epidemic Calculator that is being used in the article.

Older article by the same author: Coronavirus: Why You Must Act Now. “Politicians, Community Leaders and Business Leaders: What Should You Do and When?” (March 10, 2020)

Deutsche Übersetzung: Coronavirus: Warum du jetzt handeln musst!.

Here in Germany all schools and daycare facilities have been closed for one week already and will remain so for at least the next four weeks.

Our state and our county have issued a general decree, imposing the following rules starting last night at midnight: All public places are closed, including roads. People are not allowed to leave their houses except to go to work, or to the doctor, or to shop for essential groceries. Gatherings of more than five people are prohibited. However, you are still allowed to go for walks by yourself or with people living in your own household if you keep at least two metres (six feet) of distance to other people. The decree is in effect for at least two weeks. (Our county shares a border with the Grand-Est region of France to the South, which has been declared an international risk area.)

How to slow the spread of coronavirus

The Washington Post: Why outbreaks like coronavirus spread exponentially, and how to “flatten the curve”. (Free access.)

“[It] is instructive to simulate the spread of a fake disease through a population. We will call our fake disease simulitis. […]

Simulitis is not covid-19, and these simulations vastly oversimplify the complexity of real life. Yet just as simulitis spread through the networks of bouncing balls on your screen, covid-19 is spreading through our human networks – through our countries, our towns our workplaces, our families. And, like a ball bouncing across the screen, a single person’s behavior can cause ripple effects that touch faraway people.

In one crucial respect, though, these simulations are nothing like reality: Unlike simulitis, covid-19 can kill. Though the fatality rate is not precisely known, it is clear that the elderly members of our community are most at risk of dying from covid-19.”