See also these articles (in Italian):
Which would make sense. Inter Milano's player Romelu Lukaku was saying about a month ago that the vast majority of his teammates (23 out of 25) had already gotten the virus in January, and that for the Inter - Cagliari match (which was played on January 26th) one of his teammates had to be substituted off after only 25 minutes because he couldn't run anymore.
For whatever reasons Inter's officials didn't like his comments and reprimanded him, but it seems like Lukaku was closer to the truth than many would have liked to admit a month ago.
Perhaps because he was making baseless claims about his teammates and tainting the reputation of the club. He should at least know that players being taken down by cold or flu is not unusual in football.
2014 Seven players are struck by 'flu symptoms': https://www.telegraph.co.uk/sport/football/teams/germany/109...
2017 Wenger fighting to contain outbreak: https://www.dailymail.co.uk/sport/football/article-4296828/N...
Feb 2019 'Man flu' sweeps through League Two club: https://www.bbc.com/sport/football/47239534
March 2019 'epidemic' with eight players: https://www.thesun.co.uk/sport/football/8709002/poland-flu-e...
One could think so, of course, but then how does one explain the fact that when testing really started in Italy (end of February - actually early March for footballers, after the Juve - Inter match played on March 9th) not one football player from Inter tested positive, even though they were in what was even by then the center of the pandemic in Italy, Milano?
By contrast two Juve players (Dybala and Matuidi) tested positive immediately after March 9th, plus some other players from Firenze and Genoa. One of the only reasonable explanations would be that most (if not all) Internazionale players had already gotten the virus by then and had managed to get rid of it.
And I've heard of that "tainted" argument and for the life of me I couldn't understand it, being sick (or having been sick) doesn't taint anyone. It somehow reminds me of the infamous #milanononsiferma hashtag used by Milano's mayor (among others) at the end of February, people who were thinking that ignoring actual real stuff for fear of not "tainting" the city (in the mayor's case) would somehow make things better.
While other experts had pointed out that Italy likely had more cases than already reported, the numbers they threw around were more in the hundreds range rather than substantial percentages of the entire population: https://www.nytimes.com/2020/03/21/world/europe/italy-corona... This does explain a lot though, both about what happened in Italy and why containment efforts in other Western countries failed whilst ones closer to China geographically seem to have done much better.
That is an unlikely hypothesis, given that we didn't see an exponential explosion in deaths, and people going to the hospital until February.
1. The virus was for some reason less lethal before February.
2. Only people who don't show symptoms were catching it.
3. The serological studies are mostly finding false positives.
My money's on #3.
This happened with someone that survived SARS-CoV having effective antibodies against CoV-2: https://www.nature.com/articles/s41586-020-2349-y
If that happened, the population would be very largely skewed towards the most vulnerable (you usually don't go to ER or a hospital if you're healthy) and that would explain the uptick in deaths.
There's no other idea I can offer to explain why a disease with an estimated IFR between 0.5 and 0.9% would cause an order of magnitude more deaths.
I have been idly tracking the data here in WA. 90% of the deaths have been in 60+ years of age. Just ~30% percent of the cases. In that age range, the CFR is staggeringly high. I don't know the data for the numbers from nursing homes.
From looking at the numbers, I can't help but think we really failed protecting the elder population.
The unmitigated doubling time of COVID-19 seems to be around 2.5 days. So if about 1% gets hospitalized and people noticed after 10 or so patients with the same symptoms (that's before any of them died, mind you) you'd need about 1000 people infected. To go from 1 infected person to 1000 takes log2(1000)=9.96 doublings. So if the doubling time is 2.5 that would be 25 days or over 3 weeks before anyone would notice.
Some of these numbers are a bit of a guess but I'm trying to show that "exponential explosion" can be very small and slow at the very beginning of an outbreak.
On average an infected person seems to spread it to 2-3 persons, but we don't know the variance. It could be something like 8/10 spread it to zero persons, 1 to 4 persons and 1 to 16 persons. With low number of infected that would make the increase very noisy. In fact, it has to be so, otherwise Covid19 would explode everywhere and not be more or less containable. It has to catch momentum or whatever.
As in unlucky happenstance means three infected people in a tour group show up and infect two to three dozen people each over a weekend. You go from 3 to 100 cases in two days. R instead of being 2.5 jumped to 30!
After a week just with normal spreading you have close to a 1000 people ill.
#1 and #2 sound not entirely implausible to me though... Severity of disease seems to vary a lot with infection dose. Is it really that far fetched that when infection doses are very low the disease is mild, but as the virus level in the population rises and infection doses go up the disease becomes a very serious public health issue?
Does anybody know any data that supports/refutes my thinking above?
Remember, for #2, it is not that most people stay asymptomatic. They are usually pre-symptomatic, and do have the symptoms later. Just for the majority of folks <60, they are a bad cold. If you are under 20, not even a bad one.
And from some comments down thread, #3 is as likely to be wrong with these having more false negatives. So, tough to say.
"The test had a 98.3% specificity and 100% sensitivity"
I.e. only 1.7% likelihood of false positives
EDIT: And no case was missed
Seems rather more complex than the common account.
According to Spanish government's estimates based on their own seroprevalence study:
For the age group under 50, the estimated IFR is about 0.003%
For the age group 50 - 69 yo, it's 0.04%
And for those over 70, it's 4.1%
The study is considered to be well designed by Carl Bergstrom, for example.
: https://www.mscbs.gob.es/profesionales/saludPublica/ccayes/a... Look for the table on page 15.
For the age group < 10 yo, the estimated IFR is 0.002%
For the age group 10 - 19 yo, the estimated IFR is 0.003%
For the age group 20 - 49 yo, the estimated IFR is 0.002%
For the age group 50 - 69 yo, the estimated IFR is 0.04%
For the age group > 70 yo, the estimated IFR is 4.1%
Were you trolling, ignorant of current news, or what exactly?
It takes months to reach those levels.
In addition there's the unusually large number of pneumonia deaths in oct/nov throughout the country
Also, I claim that there was not even time to test the reliability of the serological tests an actual patients. So, anecdotes may be all data we have.
China was just the first to discover it.
If this is true, then all the Western countries took a collective dump on China, and accused them of spreading the virus.
Some theories and timelines so far:
1) July 2019, a lot of strange pneumonia cases were reported in Virginia. The symptoms sounds suspiciously like Covid19. Two people die. 
2) Three months later, on October 18, 2019, French athletes that attended the Military World Games in Wuhan reported testing positive for the Covid19 antibodies. They are muzzled, and told to not talk with reporters. 
3) December 16, 2019, The first documented hospital admission in China.
4) China investigates, and determines this is a new virus. They report it to the W.H.O. on December 31, 2019.
5) China checks past records, and determines an earlier infection was on November 17, 2019.  About a month before their previous first known case.
6) A New Jersey mayor tests positive for the antibodies, and claims he got sick in November 2019, a month before China detected their first known case. 
7) December 27, 2019, A woman in Seattle , with no travel history to China, who tested positive for the antibodies, claims she got sick two days after Christmas. This is 4 days before China reports the virus to the W.H.O. And three weeks before Seattle’s first official case.
8) Jan 26, 2020, The Lancet theorizes that the virus did not originate from the seafood market.  Daniel Lucey asserts, “The virus came into that marketplace before it came out of that marketplace.” Thus, this was not from Chinese people eating bats.
We don’t know anything for sure, but the W.H.O. needs to investigate those Virginia nursing home residents that got sick in July 2019, and test them for the coronavirus antibodies.
If, and this is a very big if, the virus did not originate from China, then, the western nations are going to have a very big egg on their faces. Especially after all their racist attacks against the Chinese people, for eating bats, and what not. And especially for demanding reparations of trillions of dollars in damages from China. Are they going to pay up instead? The mystery continues.
Unless these bats are perfectly clean and disease free, after millions of years of evolution. And somehow, only the bats in China, can carry a novel coronavirus?
I’m just pointing out that bats exist worldwide. And they can infect other farm animals. This is not a unique situation to only China.
> Conclusions: SARS-CoV-2 infection was already circulating in Milan at the outbreak start.
It just means that the virus entered the region a few weeks or months earlier than thought so far (the study started on Feb-24), not that there have been COVID-19 waves in previous years.
This seems similar to the recent news that the first case in France was backtracked to December 2019, e.g. the virus was already spreading before the first cases were discovered:
I think it has more to do with the route of entry of the virus in the territory, which hit hospitals first (not closing down Alzano Lombardo was a grave mistake), then retirement homes (an error shared with Lazio and elsewhere).
This meant that the newly-infected population was largely skewed towards the most vulnerable, and coupled with imperfect knowledge about treatment, the net result was a lot of deaths.
That said, I do think the numbers of the Policlinico study might well be representative, at least regarding Milano. It is just anecdotal, but I know a lot of people there that got sick, but where unable to get tested, or waited weeks before receiving any treatment.
Unless, of course, the antibody test is too general, and is picking up false positives, or antibodies that have nothing to do with COVID.
Just one example here: