Covid 19-A System Design Perspective
By: Praveen Kumar
Tags: Systems Thinking, Vaccines, Covid 19, Socialdistancing

Recently, I was thinking about the latest covid wave 2 in India and decided to think it from a system design perspective. That might shed some more light on why it is so difficult to deal with.

I will first explain my graph: blue arrows are good for us, they tend to decrease covid cases and green ones cause covid

Covid 19 Model

One of the most important aspects is the feedback loops that come into play here. As we already know, Covid spread because of human behaviour wherein we do not follow the social distancing guidelines. Humans being a social creature, it is very difficult to do that i.e. it is against our nature. So, we will always see people not following the social distancing norms when Covid numbers drop. Starting from the unvaccinated people, we can see that, their behaviour is then divided into 2 parts- social distancing (does not causes covid) and Parties/Crowding (which causes covid). The second behaviour will result in Covid 19 which increases the number of infected people.

My assumption of infected people is those people who have been tested +ve and also those who are unknowingly carrying the virus. If we look closely, there are two +ve closed loops, namely:

1) Mutation Loop: More the number of infected people, the more the chances of virus mutation which results in Covid becoming even more transmissible and dangerous.

2) Non-Social-Distancing Loop: This occurs due to party, functions, crowding, and not following norms. This greatly increases the risk of infection.

As has been seen in practice, these 2 loops are very dominant as this is what our pre-Covid normal behaviour is. So, what is the control mechanism. As can be seen from our model, there are 4 ways:

1) Recovered People: Those people who recover tend to break the chain as now, they have the required antibodies developed in their bodies that will not infect them. This is one of the major balancing loop that helps in bringing down the pandemic. As observed in Wave 2 in India, after 2 months, the numbers themselves came down. So, what is the tradeoff- death and massive stress on healthcare which may result in more deaths due to other diseases.

2)Social Distancing: This is one of the most effective balancing loop. It gives -ve feedback which brings down the numbers. This is why the government and celebrities keep on bugging us to follow the guidelines. Wearing masks, maintaining 1 feet distances will go a long way in preventing infections.

3) Vaccination: This clearly helps to break the chain. However, this is no balancing mechanism. This is an external input from the government. It is very effective but requires large scale vaccinations of over 1.3 billion people and 2 doses for each. It is a mammoth task in itself.

4) Lockdown: This is again an external input. It decreases the possibility of human interaction to a great extent and one of the major strategies employed by the government all over the world. However, it has a big -ve impact on our economy. So, there is always going to be a mix of lockdown and unlock-down strategies in play.

Having said all of that, if you look closely, even vaccinated & recovered people are at risk if they do not follow the guidelines properly. Even though that probability is less, it is always there. Remember, vaccines are not 100% effective and recovered people have also gotten infected in many cases.

So, now you know why Covid is so uncontrollable for us!

Take care everyone and stay safe! :)