On: Covid-19 is becoming less deadly in Europe but we don't know why

[ivars]

I've heard that vitamin D play a big part in successful recovery. Northern Hemisphere gets their vitamin D mostly in summer so this is the time when European immunity is the strongest?

[soganess → ivars]

As far as I can gather this claim stems from a single non-peer reviewed preliminary report from back in may:

https://www.webmd.com/lung/news/20200518/more-vitamin-d-lowe...

https://www.yalemedicine.org/stories/vitamin-d-covid-19/

[ivars → soganess]

There are many. For example:

https://link.springer.com/article/10.1007/s40618-020-01370-x