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

https://www.newscientist.com/article/2252699-covid-19-is-becoming-less-deadly-in-europe-but-we-dont-know-why/

by bookofjoe • 6 years ago

19 9 6 years ago

bookofjoe• 6 years ago

Evaluating the effects of SARS-CoV-2 Spike mutation D614G on transmissibility and pathogenicity https://www.medrxiv.org/content/10.1101/2020.07.31.20166082v...
Estimating the infection fatality ratio in England https://www.cebm.net/covid-19/estimating-the-infection-fatal...

orobinson• 6 years ago

As the article mentions, it seems more likely that the decreasing death rate is due to higher rates of young people being infected vs older people. Also due to increased testing catching the less severe cases.

Back in April here in the U.K even healthcare workers weren’t getting tested. Now you can get a test posted to your house for free if you show even the mildest symptoms, so much more of these mild cases are getting counted.

Also, anecdotally, older people are still taking precautions to minimise contact with others whereas younger people are basically going about life as normal. Hence, the virus is spreading around younger people much more than older people. For example, the U.K had a huge number of deaths in care homes earlier in the pandemic but I believe most care homes are still locked down to some extent while at the same time the pubs are open and kids are heading back to school next week.

ivars2• 6 years ago

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• 6 years ago

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/

ivars2• 6 years ago

There are many. For example:

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

gregoriol• 6 years ago

It's hard to compare to march: there were no testing numbers at that time, it's impossible to know how many cases there were back then when hospitals started to get full of very sick people. We'll probably know in a few weeks.

badhabit• 6 years ago

probably because the most vulnerables are already phased out leaving the more resistant types

iforgotpassword• 6 years ago

From what I can tell looking at friends and family, a lot of people are currently returning from vacation, and it's been on the news a couple times that those people are bringing back covid, presumably visiting bars and clubs depending on where they traveled, easing the spread.

That would explain why it's becoming less deadly. The old and vulnerable don't travel, so we have a disproportionate amount of young people getting infected which recover well. Let's see how many of those who return can't resist visiting their grandparents in the first two weeks after returning. Maybe we get a delayed deadly wave when it hits the retirement homes again.

perl4ever• 6 years ago

It seems obvious to me that the more people isolate, the more there is evolutionary pressure on the virus to become more infectious and less virulent. Even if people didn't "social distance" there would be some pressure, but the better they do it, the more there is.

I think I remember people saying similar things months ago, and being called ignorant idiots by angry people on HN, but I was never sure exactly why.

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

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