Today was a terrible day all around, Italy, Spain, Us, and finally the UK. Another 56 people lost their lives. The fact that another thousand people were also reported infected just underlines the looking disaster.
Modelling epidemics is an extremely complex and far from accurate science. However, that’s only needed if you want a very accurate result. If you only need broad figures under very exact conditions, that’s easy enough you can use a spreadsheet to calculate it. A new study from the Imperial College underwrites some initial findings from the chinese doctors attending to the initial epidemic.
The main findings are:
- Average time between symptoms onset and a positive detection – 2 days
- Average time between a positive result and a fatal result – 14 days
Then, we can also consider the current figures for the countries initially affected by COVID-19: China and South Korea, which represent opposite ends of the spectrum:
On South Korea one can observe what happens when the disease is caught on time, and entire populations are tested against it. In this case, the fatality rate is around 1%. Consider this the minimum obtainable fatality rate on a developed country with the current treatment protocols.
On China you can observe how that 1% can escalate when the health system is overwhelmed. At the peak of the crisis, fatality rate reached 6.7%, when considering resolved cases (not new infection cases).
Both values puts a lower and higher boundary on the number of victims, unless new therapies or a vaccine appears. Here we can take two references, the 10% mark, the point where the infection rate stops being exponencial (due to the fact people stop getting infected because they already are) and the 60% mark, which Boris Jonson targeted as being sufficient for herd protection. The problem here, is that no matter what you do, you can’t avoid the minimum fatality level, and most likely the higher one unless you control the epidemic. This results on at least 66000 deaths at the 10% mark to 398000 deaths to obtain that 60% herd immunity Boris Jonson aimed for, never mind a worst case, but likely scenario of, 2.67million deaths in the UK alone. No further comments are in order.
As now we have a well established trend, we can have a 24 fatality forecast, and the 16 days fatality forecast.
For tomorrow:
6332 cumulative infections and 293 cumulative fatalities.
In 16 days, on April 7th, the first day that any measure will have an effect on fatalities, the UK will already have at least 11577 fatalities. I really hope I’m wrong.
As usual the source spreadsheet is available here.