(Edit: Please ignore below.
Checked the latest literature and cross-reactive antibodies have not demonstrated correlation with either preventing infection or hospitalization.  
 https://blogs.sciencemag.org/pipeline/archives/2021/02/10/do...  https://www.medrxiv.org/content/10.1101/2020.11.06.20227215v... (pending publishing in Cell, but linked ArXiv for availability) )
Because pre-existing coronavirus antibodies have been proven cross-reactive to SARS-CoV-2.
And different populations have different endemic coronaviruses circulating in them.
This isn't some great mystery. This is a normal Tuesday for how human immune systems are supposed to work, as a species.
Obesity makes you 3 times more likely to be hospitalized for covid.
When looking at the world map of obesity right next to the world map of covid mortality, the correlation/causation is startling.
America and Europe have the most obese people and the worst covid health outcomes, Africa and Asia have the least obese people, and the best covid outcomes.
The sample size of this study was only 251 people, apparently all from France, according to a comment on the study, though I could not confirm or deny that fact from searching through the source text.
In order to rule out cross reactivity, we'd need a much larger study comparing samples across many regions.
In this age of widespread global travel, is that true anymore?
TL;DR: Maybe. There is some evidence showing a link and other showing no link. Some lab studies show T cells get a response., but other studies show no statistical link.
> New Zealand,
> South Korea
Effectively an island—peninsula with the only land access being through the most heavily militarized border in the world.
When I suggest we should suspend all air travel except for freight and bring back border checks in the EU during lockdown, all my friends react like it's pure heresy.
In hindsight historians will look back at this as our biggest failing. Allowing for travel in the name of economy whilst prolonging economic damage plus increasing disease/deaths.
Half measures are a short distance from no measures at all in terms of virus containment.
In summary, we fail to find strong evidence supporting a role for more restrictive NPIs in the control of COVID in early 2020. We do not question the role of all public health interventions, or of coordinated communications about the epidemic, but we fail to find an additional benefit of stay-at-home orders and business closures.
The data cannot fully exclude the possibility of some benefits. However, even if they exist, these benefits may not match the numerous harms of these aggressive measures. More targeted public health interventions that more effectively reduce transmissions may be important for future epidemic control without the harms of highly restrictive measures.
If you think about it, most countries in the world only have limited ports of entry (no matter the size of the border), and if a national government shuts off these ports of entry, the country essentially becomes an "island" whether they have a surrounding body of water or not. (assuming strong borders and no illegal traversals -- which may or may not be good assumptions depending on where you are, but it's a simplifying assumption for the sake of discussion).
Montreal is an island but its COVID rates are far worse than Toronto. There's nothing special about being an island. It's about the connectivity.
However, up until recently very lax on air travellers and even now actually checking some.
In an alternate measure, we finally see a NY-based trip enter the list at number 8, with the countries listed above remaining much busier: https://en.wikipedia.org/wiki/List_of_busiest_passenger_air_...
This is what I found for Australia:
> Since March last year, Australia has essentially allowed only returning residents to enter the country, provided they complete a 14-day quarantine - usually in city hotels.
It seems they stopped allowing tourists to fly and were very strict from very early in the pandemic
There's no need to look for explanations in exposure to bat coronaviruses when there's so much Vietnam did that the USA, UK and Europe didn't do. This isn't just about government actions, but the individual actions of the population too.
I suspect it is a) making sure vulnerable people are really isolated (care homes for example), b) a better health system.
I would like to see a plot of death rate vs hospital beds... found this  that argues that it has potentially a small effect, but doesn't explain everything.
If you do a worse job finding asymptomatic cases, your death rate gets higher even more people didn't die.
Western governments simply didnt have the ability or the desire to regulate ventilation and, at the beginning were prioritizing keeping the economy running (ironically enough).
All these countries worked very hard at the start of the epidemic to bring it under control and were successful.
The state of Victoria in Australia is the best example of this. After initial elimination, it started to get out of control and so they entered a very strict 112 day lockdown until community transmission went to zero.
Since then most Australian states have done similar (but shorter) lockdowns, again until community transmission is zero.
When community transmission is very low (<100 cases) things like contact tracing work, communities support short lockdowns etc.
Once it gets out of control many control processes become useless, and exponential growth takes over.
>Why is this not our primary focus of discussion?
Because mainstream science also has their own set of beliefs which are dogmatic in nature.
Moreover would a govt/big business come forth and say, so we introduced a new detergent formula in the market and this cause the whole outbreak? that has never voluntarily happened.
Just look at several nation with no lock downs - and there are no reports of people dying in mass numbers. In fact I doubt if there is even a new pathogen around.
In countries that have had serious COVID issues such as the UK and USA we see little to none of the above. As an example there was a discussion I watched where someone from California went for a road trip to neighbouring states despite the local authorities asking interstate visitors to stay away. When challenged about visiting states asking people to stay away, their reply was basically, "I don't believe I'm doing anything wrong, and you can't legally stop me." This attitude was prevalent from the top down.
One big issue in the USA is the number of people who simply can't afford to stay home from work, and whose multiple jobs require being present in a building with lots of visitors. In Australia we've had a number of "flare ups" where people involved in the quarantine program have ended up with COVID and spread it to the community because they are the lowest paid workers in the country and need three jobs to keep food on the table (or as a security guard they had multiple shifts moving between sites). As much of a joke as our hotel quarantine has been, it's at least something we can do to limit the community transmission of COVID-19.
There's nothing magical about Asia/Oceania countries managing COVID well. You just have to accept that COVID-19 is real, the medical authorities what they're talking about, and personal liberties sometimes need to be curtailed for the benefit of everyone.
At the personal level, wear a mask in public, keep your hands clean, avoid unnecessary travel, stay away from people. Sometimes you have to exercise your responsibilities instead of your rights.
At the corporate/national level, pay (poor) people to stay home, shut borders where required to prevent community transmission. Lock down neighbourhoods with high community transmission. Make sure testing is free and widely available.
If you believe "the economy" is more important than the people, you're not going to handle pandemics particularly well.
Contract tracing is very effective, but its hard to "scale." The virus exponentially grows, so once the infection rate is higher than your capacity to contract trace, you've permanently lost the battle.
Only really China, South Korea, and Australia have had substantial outbreaks that were later contained. But in each, the outbreak was geographically or socially relatively contained: Wuhan, Shincheonji Church, and Victoria.
SARS-CoV-2 is severe in old people and obese people, and very few outside that demographic. Wealthy nations have a much higher obesity rate than poorer nations. The US has ten times the number of obese individuals than India, three times as many as Nigeria. Wealthy nations have a larger proportion of the population in older age cohorts. The US has five times as many 65+ people as Nigeria.
I have no idea why the media persistently chooses to avoid these points. The research community has been turning out review papers by the score to point out, very bluntly, that COVID-19 mortality falls near entirely on the old and the obese.
When his researchers analyzed the data by age, location, and gender, they found that excess deaths tended to be observed in younger cohorts, and in rural rather than in urban settings; nor was there evidence of the usual coronavirus skew toward greater lethality in men
Its conclusion can probably summarized as "We don't really know yet, probably population, health standards and living conditions, government policy and communication, maybe T-Cells, definitely poor data".
The article is about the ways scientists are attacking an intriguing scientific question with enormous societal importance. It certainly does not have the answer to the question in the title, and if you kept reading while expecting one then maybe you missed the phrase "the greatest conundrum of the pandemic" in the introduction?
Altogether your comment, and the support it gets here, make me despair a bit for the popularization of science in general. Is such a well-written report on the scientific process itself dismissed so easily? Do we really only care about the answers?
I don't know what exactly you mean by "new", but remember it's not published in a scientific journal. It isn't supposed to contain anything fully original.
For us common folk- I think there were lots of new & interesting stuff there.
That is what is expected from the New Yorker
They found that the total number of “all cause” deaths reported between May and August almost doubled in India compared with the same period in each of the past five years.
“Is that because the number of covid deaths in the country has been vastly underestimated?” I asked.
“It’s impossible to have a decisive answer,” Shah told me. “But the pattern of the excess deaths doesn’t really shout out covid as the cause. It just doesn’t... The telltale signatures of covid just aren’t there,” he said. He won’t venture any hypotheses about the cause of the excess deaths. But among the possible candidates are indirect consequences of the pandemic: wage loss, displacement, malnourishment, forced migration, and disruptions in health care...
>With respect to the raw numbers, underreporting is an enormous problem; differences in age distribution, too, make a very deep cut, and perhaps the models must further calibrate their weightings here.
They go on with the complex speculation about other causes, but obviously bad data is a huge driver of this anamoly. Bad data we can be sure of, the rest is speculative narrative.
The article makes a strong case that bad data only closes the gap partially.
The fact that the one place in Africa that got hit hard also happens to be the most industrialized/westernized place can't be a coincidence.
That leaves a lot of options though. Diet? Obesity? Social habits? Ability to travel internationally? Pollution of some sort? Plastics? Could be anything
In Norwegian: https://www.aftenposten.no/meninger/kronikk/i/awEP27/derfor-...
Without actually knowing the situation on the ground, I'd say there's less antibiotics in food production in India/there's more bacteria going around that Indian immune systems are better prepared to fight the bacterias or antibiotics work better to kill them.
But well, it's another theory...
And depending on the testing (availability, sensitivity) the death counts could be underestimated as well.
It will be an interesting challenge to get compatible statistics from different countries.
But not everyone who has 'coronavirus' on the death certificate... Just to be clear here, if excess death rates are to be believed, it's likely that the UK is under reporting deaths.
PS: The "any cause" thing is also untrue, as far as I can see. Apparently, 88% of COVID patients who die do so within 28 days, so you can sort of guess at the undercounting going on here.
It is well understood that age, hypertension (stress?) and obesity are major driving factors of covid-19 hospitalizations .
I would love to see governments spending as much money/resources on stimulating a healthy lifestyle as the do on vaccines and lockdowns.
Somewhat tangent, a virus killing even 20% of the West (and spare the rest) would spell unimaginable doom on said rest by second-order economic effects.