We are getting daily updates on the number of confirmed cases of COVID-19 however for a case to be confirmed, people need to be tested and it is clear that there are many people with the virus are not being tested. This may be due to the fact that many people with the virus are asymptomatic or have a mild illness at worst and so do not seek testing. In some cases it may be that you need to meet certain criteria such as overseas travel or contact with a confirmed case to be eligible for testing. Whatever the reason, the reported number of Coronavirus cases must certainly be far fewer than what is actually out in the community.
Estimating actual case numbers
The reported statistic that is probably the most reliable is the number of deaths due to COVID-19. Currently when a person dies in a hospital of a pneumonia it is highly probably that they will be tested for COVID-19 and if found to be positive they will be reported as such. It is unlikely that in the developed world, someone would die of Coronavirus and it not be recorded.
Based on this assumption we can use the death rate as an indicator for the number of cases that must be out in the community however to do this we need a few more things. First and foremost is the mortality rate, but we also need to understand timeline of the progression of the…
