Is Weather a Good Marker for COVID-19?
The marco level discussion of how the prevalence rate, incidence and hazard rate, reproductive rate, mortality rate vary in each country comes first, followed by a granular exploration on how weather condition matters in this secenario.
Five Countries of Interests:
Canada, Finland, Belguim, UK and Australia are five representative countries
What do we know about the mortality rate of COVID-19?
Two ways of calculating the disease mortality are introduced, which are case-fatality ratio (CF) and outcome-fatality ratio (OF).
Case-Fatality ratio measures the number of deaths to cases in the population upon a certain date, relative to the number of cases. Outcome-fatality ratio measures the number of deaths relative to all cases. Typically, OF decreases and CF increases with time, until they meet somewhere in the middle. In our case, these two values converged eventually to a steady state at the end of 150 days in Canada, Australia and Finland, while OF > CF in the United Kingdom and Belgium because COVID-19 was still an ongoing disease happening during the same period. In particular, the situation in the United Kingdom was way more worse than expected with a consistent high value for the outcome-fatality ratio. The coronavirus had an fatality rate of ~10% in Canada and Finland; ~3% in Australia in the first wave of the disease.
R-nought: The basic reproductive rate is not a biological constant
R-nought is a measurement of how the epidemic will evolve without any intervention, a value greater than one indicates that the disease will become an epidemic; a value equal to one means the disease will become endemic; a value smaller than one represents that the disease will eventually die out. The scientific community carried out a prediction of R-nought between 1.4 to 5.7 for COVID-19.
The reproductive rate for Belgium was incrediably high with a value of 4.644567, compared to other cases where the values were mostly just above one. Weather?
