Covid-19 why does it seem like nothing is happening? #mycoviddiary

In and around town there are people who are looking at all of the rest of us who are hand sanitizing and social distancing like we are crazy. I feel for them. They are simply trusting their own experience. They don't see people dropping like flies. Nobody they know even has a cough. Restaurants are closing and it looks like everyone is needlessly panicking. What gives? Why are they wrong?

The reason it seems like nothing is happening while governors and doctors are predicting huge numbers of people who will be sick and dying is something called exponential growth. That means that the number of cases of this disease are increasing faster each day.  In a time of exponential growth things seem really mellow at first, as the number of cases goes from 2 to 4 in one doubling time, just 2 more cases, what's the big deal? Then the next doubling time the 4 cases become 8, but that's not so bad, just 4 more cases. Days go by... when you get to the tenth doubling period with 1024 cases and that number doubles it isn't funny anymore because the next day there are 2048 people with the disease, 20% of whom need to be in the hospital and your hospital only has 25 beds. With the 1918-1919 influenza epidemic which is pretty similar in many ways to this, 30% of people got sick before it was over, in our town that would be somewhat over 6000 people. I'm not going to belabor the numbers. Just saying... that is way more patients than we can handle. Also, they tend to stay sick for a long time, so the first 25 might fill up the hospital and then there's no room at the inn! Death rates may be as high as 5%, but I imagine it would be worse if there was no way to care for them at the hospital. Those of you who live in a small town might say "what about going to the larger hospital in the next big city?" Nope. They will be full too. 

The increase in cases will slow and then stop eventually because people get immune and stop passing it on to others, but that takes awhile. I have drawn a little graph to explain it in a general way.

So that's why the people who are not taking this seriously are wrong. We are on this curve and we can flatten it if we do the stuff we're supposed to but we can't get off of it. Flattening of the curve means that the numbers of patients increase more slowly. It will then take longer to reach the peak number of patients, but we will be less overwhelmed and will be able to care for them better. That scenario is most likely in places that are less densely populated. In our small rural town it may be possible as well as in certain agricultural areas or states. Let me be quite clear: if we socially distance ourselves and practice excellent hygiene and infection control, fewer people will get sick and things will not look so bad.

Some people who follow the news ask why China has had so few cases. The population of China is nearly 2 billion people. The explanation I have heard is that the virus was almost entirely contained in Hubei Province and, within that, the city Wuhan. There was no travel allowed out of Hubei Province and within the city of Wuhan and the province there was extensive testing and strictly enforced social distancing. According to news, there have been no new cases in China for two days now after an epidemic that started around the beginning of the year. The province of Hubei has 58 million people and the city of Wuhan 11 million, and with a total of around 80,000 cases in all of China, far fewer than 30% of people were infected. Their strategy clearly worked pretty well. Unfortunately very few people in China are immune and it is a crowded country with significant poverty. When the coronavirus is either re-imported or some infected toddler without any symptoms transmits it to his many little friends and their parents and grandparents the whole epidemic could be rekindled. Nobody really knows what will happen in the next year. When a vaccine becomes available all of this will improve tremendously.

More on exponential growth and epidemics:

There are some really good explanations on YouTube:
For the nerdy: this

For regular people: this

For people who love Harry Potter and are ready for an exponential growth metaphor: this