COVID-19 simulation

- Or "how 30% of people can save the world?"

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It's November 2020. There is no cure for COVID-19. What can we do to prevent the disaster?

Let's take a look at several simulations of the spread of the virus.

I recommend to visit website from desktop for better experience. Phone may has performance issues.

Simulation rules


Desease lasts a long time: 2 to 5 weeks.

30% of people develop severe symptoms. They are especially vulnerable in a case of a lack of medical care due to overwhelmed medical facilities or weak healthcare systems.

3% of people are destined to die. [Source]. It is due to genetic and age reasons. We are assuming we can save the people through vaccination or isolation. Unfortunately as of November 2020 there are no vaccines approved for public use.

Possible states of a person

- a healthy person.

- a sick person. They infect other individuals in a small area around them.

- a seriously sick person with severe symptoms. They die if the medical system is overloaded. We assume the healthcare system can handle a maximum of 200 patients at a time. Also, severely ill patients move much slower than other people.

- a dead person.

- a recovered perso. We assume they have developed an immunity and can not get reinfected.


- a person with mask. Mask retains up to 50% of exhaled viruses. Also it retains up to 40% of inhaled viruses. If both persons wear masks a synergy effect appears.

- a person with screen. Screen additionally protects against infection.

- a person with screen and mask.

Let's get started

Virus in a small virtual city

There is a virtual city with population of 2 000 people. People contact each other as usual. No measures are taken. What could go wrong? Check it.

Start No sick people left. Pandemy is over. Reset
Hint: game field is scrollable

At the end of simulation you will see that everyone get desease. Results may vary, but I had a disaster my first simulation. I have got up to 1500 sick people at same time andui 600 dead people at the end. These are 75% and 30%, respectively. Each person with severe symptoms died.

Isolation of sick people

We have not taken any measures to protect people. Obviously, we can isolate patients in hospitals. Let's be honest, complete isolation is not possible. Patients will still be in contact with service personnel, such as doctors, janitors, couriers. So the virus can be passed on, but it happens less likely.

Let's see how this affects the spread of the virus. It is a perfect scenario! Be prepared it takes long time. I recommend to move ahead after 90th day, there is nothing interesting in the following days.

Start No sick people left. Pandemy is over. Reset
Hint: game field is scrollable

Wow! In my simulation there were so few infections that medical care was enough for everyone. Over time, the number of people with immunity increased. At some point, the patients were in contact only with people with immunity and could not spread the virus further.

My result is 70 people who died over 498 days of pandemy. Exactly 3% that are in the genetics of people. So, what is your result?

Isolation of sick people in real life

Sadly, not all people observe isolation. And alas, not all sick people know that they are ill. There is no scientific work reporting how many people are asymptomatic. In my city one clinic said 25% of its positive tests were from people with no signs of illness. Let's take this number as a basis. 25% of those infected will not show symptoms and will move freely around the city.

Start No sick people left. Pandemy is over. Reset
Hint: game field is scrollable

Well, the burden on the healthcare system is still less than in the very first scenario. But a cemeteries are overcrowded again.

Isolation of sick people in real life. But with masks and screens

May be masks and screens will help? Of course not all people wear them. Let's say 10% of people wear screens and 50% of people wear masks.

Start No sick people left. Pandemy is over. Reset
Hint: game field is scrollable

Hmm. Although the effect is small, it is there. Why masks have not worked? Actually they worked. But if you have chance of infection as 5%, 20 contacts turns it to 74%, that's it! How many contacts do you have in pub or in club? Do you consider you are breathing the same air with all the pub visitors?

Isolation + masks + screens + self-isolation

So, our goal is to reduce the number of contacts. It's time for self-isonation. Don't forget to build houses for everyone in our virtual city in advance.

In this case we have a chance to isolate people who do not know they are ill. One more modification in this simulation is prevention of infection through the walls.

I live in Russia. So I will draw on the experience of my country. The Moscow mayor's office has obliged business to send 30% of employee to work from home. Let's check what happens when this order is respected.

Start No sick people left. Pandemy is over. Reset
Hint: game field is scrollable

This set of measures has shown maximum efficiency. About 70% of people did not even get infected by the end of the simulation.

This is most effective step in fight with epidemy.


I hope you drew the right conclusions. Please, help me convey information to more people. Share this page to somewhere.


You can play with combination of parameters here

Start No sick people left. Pandemy is over. Reset
Hint: game field is scrollable