We’ve seen what has happened in Spain and France which have the fourth and fifth highest death tolls in the world. How widespread is COVID-19 in those countries?
Only 5% of the population of Spain and France has been infected.
Another IFR datapoint: with serology testing estimating that 5% of Spains population was exposed, 27,104 deaths, and a population of 46.9 million gives an infection fatality rate of ~1.2%. https://t.co/RxtTJjjxfe— Zeke Hausfather (@hausfath) May 13, 2020
BREAKING NEWS: Preliminary results of Spain’s seroprevalence study #ENECOVID.— Miguel Hernán (@_MiguelHernan) May 13, 2020
Antibodies for #SARSCoV2:
5% of Spanish population
11% in region with highest incidence (Madrid)
So far from herd immunity in country with 2nd largest number of cases after U.S. https://t.co/P8dpzaibuX
Quick and dirty calculation of mortality risk:— Miguel Hernán (@_MiguelHernan) May 13, 2020
27,100 #COVID19 deaths
a preliminary estimate of 2.35M with IgG antibodies in early May (5% of a population of 47M)
A ballpark estimate that may change after statistical adjustments and validation studies.
Today both France and Spain (two badly hit countries) have come out with seroprevalence numbers. (France is a model, paper linked below. Spain was representative sample/survey of 60K; I don’t have the paper yet). Both are ~5 percent. If that holds up, that is very very bad news. https://t.co/Tr7sCEXtrT— zeynep tufekci (@zeynep) May 13, 2020
One hopeful scenario had been there is a lot of asymptomatic transmission we are not noticing. Maybe. But if some of the worst hit countries are still composed of almost completely immunologically naive populations, that’s a different challenge. Quite confusing, to be honest.— zeynep tufekci (@zeynep) May 13, 2020
Clarification re: my Sweden seroprevalence question. Lancet article said 25 percent for Stockholm. The question re:Spain and France only at 5 percent remains, though. If that’s the real seroprevalence, big death toll despite (relatively) limited spread. https://t.co/lFUuNhQ5dh— zeynep tufekci (@zeynep) May 13, 2020
Even the worst hit Spanish regions appear to be at ~10-14% seroprevalence. Hopefully we’ll have more distribution/network data—but one guess would be the spread in nursing homes/vulnerable populations couldn’t be checked even as everyone else locked down. https://t.co/WaWE3xa2lh— zeynep tufekci (@zeynep) May 13, 2020
Here’s a super helpful expert thread on squaring Sweden’s claims with the seroprevalence numbers emerging elsewhere. https://t.co/lu0s425NFj— zeynep tufekci (@zeynep) May 13, 2020
New Indiana data. Random sample. Prevalence: 2.8% These findings contradict the hope that many had mild/asymptomatic infections and are now immune. This suggests places that were spared (so far) did not have big outbreaks. https://t.co/O0R9mEc1Xl— zeynep tufekci (@zeynep) May 13, 2020
Yes waiting for the paper and the details. This appears to be the first wave. https://t.co/RlBh648SxO— zeynep tufekci (@zeynep) May 13, 2020
Only 2.8% of Indiana’s population has been infected.
Once in a while, I get to talk about my own back yard. Indiana just conducted the first statewide random sample study to determine the true prevalence of COVID-19. The results may surprise you.— Aaron E. Carroll (@aaronecarroll) May 13, 2020
Too Many States Are Flying Blind Into Reopening. Not Indiana. https://t.co/6mHHmOKS5d
Now to results!— Aaron E. Carroll (@aaronecarroll) May 13, 2020
How many are currently infected? 1.7%
How many more have antibodies? 1.1%
Total prevalence in Indiana? 2.8%
Anyone hoping that great numbers of Americans have been infected, but with no symptoms or very mild illness is going to be disappointed.
This means, however, that Indiana is currently missing 10 out of every 11 cases. We’re not testing enough.— Aaron E. Carroll (@aaronecarroll) May 13, 2020
More calculations possible with a denominator. The infection fatality rate is 0.58%
This is worse than the flu.
What percent were totally asymptomatic? About 45%
How long does it take to get to herd immunity?
The virus would have to spread through 60% to 70% of the population. The only place in the world where antibodies studies have found it close to that level of seroprevalence is the hardest hit towns around Bergamo in Northern Italy. New York City is only at 21%.
Note: 71% of Republicans currently think the worst is behind us!