Crunching Israel’s Corona numbers
Israel was praised for its early handling of COVID-19, then the numbers went up and the country served as a deterrent. A second lockdown is now followed by a third one.
However, Israel is one of the first countries to roll out the new vaccine en masse. As of the time of writing, some 300 thousand people, 3 percent of the population, have received the first dose. There is no question we are witnessing an impressive early number.
By today, Dec 27, 2020, around 400 thousand Israelis have tested positive for COVID-19 and around 3,200 have died of it. Although in the worldwide comparison Israel is doing “very well”, the numbers sound disturbing for a country with a total population of less than 9 million people.
Luckily, the government provides some data to look into and to analyse the situation (in Hebrew only).
Among many interesting and reasonably well designed graphics, however, I am missing one that would help me a lot. I want to know what is my risk. Of course every person is different, but so far the single biggest factor to explain the outcome seems to be age.
Where is the graph showing my “survival” chances? I am 34. Not the youngest anymore, but it could be worse. The closest I can find to answer my question is this chart:
30–39 blue (male) is my group. 7%…
It sounds crazy,… but one moment. By default the chart shows the positive tests (מאומתים), while the percentage is the fraction from all positives. This number is not at all helpful!
I look around and find a button on the top left of this very chart. I can switch now from “positives” to “deaths” (נפטרים):
30–39 is now at 0.4%. It sounds quite high, given that a regular flu is somewhere around 0.1%. But again, the chart shows the fraction from all deaths. It does not help me to understand my own risk.
That is unhappy but there is a will, so there will be a way:
I copied the numbers to a spreadsheet and did the calculation:
It turns out that while the average fatality rate is 0.81%, for my age bracket it’s just 0.04% or 1 out of 2,300! This is quite a reason for optimism, I mean from 27,637 males my age who got COVID, only 12 passed away. It might be even reasonable to assume that from these 12, a few had some significant preexisting condition that I do not have.
Great news for me so far. What is however very concerning is the shape of the fatality rate curve:
I wonder why the government would not add such a simple graphic to its dashboard. If you are above 60, and you see this chart, you will be very careful where you go and what you do…
Vaccine math
And while already here, I also calculated the very very simplified impact of the vaccine.
It turns out that if I just projected the numbers based on how many people already got COVID and how many people there are in the respective age group, if we get to an infection rate of 100% we will be expecting over 75 thousand more deaths from COVID!!
I agree that this number is probably way too high, but the calculation is straightforward and it helps to understand the point.
Assuming that the vaccine will be 95% effective in preventing people from passing away, it could save almost 72 thousand people:
That is great news. Technological progress saves lives.
However, I would like to point out that no discussion about COVID should go down without an economic argument. As you can see in the above table, vast majority of lives would be saved in the lower half of the table, meaning for people above 50 or even 60.
Once aggregated the numbers look even more impressive: in order to save over 98% of people who could be saved by the vaccine Israel needs to vaccinate less than 25% of its population, i.e. all the citizens above 50 years old:
Assuming that immunity is reached within 30 to 45 days of the vaccination, Israel could “solve” the pandemic by the end of February.
By the way, it would also mean that suddenly there is much more space in the hospitals. So that even the 5% for whom the vaccine did not work would have much better chances than implied in Tab 1!
Therefore, for the local government it might make sense not to incentivise vaccination of people below 50, unless there is a preexisting condition of course. The vaccines are expensive and so is their transportation and maintenance.
The economy would be saved by vaccinating the elderly while younger population presumably will have little side effects from getting COVID.
