30th September 2021
Covid deaths per million for 189 countries plotted against vaccine rollout
Here’s a superb set of slides (right click and “save the link as”- if Chrome creates a nuisance, try Firefox). Jason Gavrilis that challenge us for an explanation.
The problem with this is, of course, that there is no simple relationship between these variables. Other factors (apart from vaccines) that explain deaths include: the population structure, the health of the population, Vitamin D sufficiency and the strictness of lockdowns.
Creating a panel data set with all relevant variables and trying a regression could potentially provide a clue. (Btw, time series analysis creates enormous level of statistical complexity – but panel data analysis is a task very few people are competent to undertake. I’m completely clueless how to do it – my PhD didn’t require panel data regressions).
My hypothesis for Israel (just like for Australia) is that due to extremely harsh and costly lockdowns, these countries had a lot more vulnerable people in the population (i.e. those who did not get natural immunity, like in India – where there was a vast – over 60% – of natural immunity by mid-2021). That would explain their higher (comparative) surge despite vaccination (since vaccines are not entirely effective). Of course, Israel’s lockdowns don’t look anywhere near as draconian as Australia’s, from the chart.
Another key factor is antibody levels over time. India’s example is likely explained by high prior immunity + high levels of antibodies by mid-2021.
Seasonality perhaps to be included (to reflect Vitamin D) – so we need to understand how UV patterns vary across the year in different countries (e.g. https://www.researchgate.net/publication/341200127_UV_light_influences_covid-19_activity_through_big_data_trade_offs_between_northern_subtropical_tropical_and_southern_subtropical_countries/link/5eb374c445851523bd49867d/download).
There are many other factors. Determining any causality between vaccines and covid deaths through such macro-level analysis is going to be very hard – but who knows. Let people attempt all the innovative analyses they can, and maybe we’ll get new insights.
Mathieu, E., Ritchie, H., Ortiz-Ospina, E., Roser, M., Hasell, J., Appel, C., Giattino, C., & Rodés-Guirao, L. (2021). A global database of COVID-19 vaccinations. Nature Human Behaviour, 5(7), 947–953. https://doi.org/10.1038/s41562-021-01122-8
Hasell, J., Mathieu, E., Beltekian, D., Macdonald, B., Giattino, C., Ortiz-Ospina, E., Roser, M., & Ritchie, H. (2020). A cross-country database of COVID-19 testing. Scientific Data, 7(1), 1–7. https://doi.org/10.1038/s41597-020-00688-8