#worldometers
COVID-19: What is Turkey's true case count?
As noted 8 days ago, Turkey had revised its COVID-19 reporting criteria on November 25 to include asymptomatic cases, increasing its daily reported cases by a factor of 3.6 literally overnight. With cases now averaging 32,000/day and rising, and 925,000 officially reported cases (ranked 16th overall, behind Peru) the country is three days from crossing the million-case threshold, officially.
But we know that this is a spectacular undercount. The question arises, what is the likely actual number of cases?
I'll argue that this is 2.1 million (6th ranked) with a true ncidence of at least 3.5 million, possibly as high as 5 million, based on prior undercounts and observed mortality.
Data are all based on Worldometers unless otherwise noted.
Underreported diagnoses
We can look at the change in reported new daily cases from 24 and 25 November 2020. On the 24th, Turkey reported 7,831 new cases, on the 25th, 28,351. Turkey ranked 24th among countries on 24 November.
Case progression before and after both point was nearly identical --- for the three days preceding the 24th, increasing by an average of 583 new cases/day, by 584 for the three days following the 25th. Expected progression from the 24th to the 25th would have been about 584 cases. Actual was 20,520. The actual value was 3.55 times greater than expected.
This suggests Turkey had previously only been counting 28% of diagnosible cases, or omitting 72% of cases that would be classsified under post-November 25 criteria.
We can adjust the Nov 24 cumulative case total by multiplying the reported 460,916 cases by 3.55, giving about 1.63 million cases. Adding the additional 432,714 actually reported cases since, the current total as of 9 December using current diagnostic criteria would be 2.07 million. With this revised value, Turkey ranks 6th in reported cases overall, following France.
Estimations based on mortality
Another approach is to estimate total cases using a presumed incidence fatality rate (IFR) and average duration from diagnosis to death. This makes several additional assumptions, overstates the number of cases compared to typical diagnostic and testing practices, typically by a factor of 6--8 or more, and may be inaccurate. It remains a useful sanity check.
A key assumption is that Turkey has been consistently reporting all actual COVID-19 deaths. I've some questions about this as there is also a sharp uptick in these numbers, though beginning slightly earlier 17 November. I'm assuming this reflects ground truth and not a reporting change.
With a 9 December report of 15,531 deaths, an assumed IFR of 0.5%, and a two-week average duration from diagnosis to death, my calculation is that the true incidence count as of November 25 was 1.7 million cases. Adding the known 432,714 diagnosed cases since, the true total incidence on December 9 is likely at least 3.5 million cases.
Given that testing still underreports actual incidence by a factor of 6--8, as noted, the total could be approaching 5 million actual infections.
As few countries even approach comprehensive testing, assigning a rank is inappropriate. France, previously mentioned, is highly suspect given a case fatality rate (CFR) of 25%, some fifty times greater than expected, stronly suggesting underreporting of actual cases. I'll not that by total reported deaths, Turkey still ranks only 20th overall, trailing Indonesia, Belgium, and Chile.
Summary
Turkey currently reports 925,342 COVID-19 cases (16th overall by country) where the actual reported value based on curent reporting criteria should be 2.1 million cases (6th overall), and the underlying incidence of all infections is likely 3.5--5 million.
Turkey isn't the only ... data turkey
Whilst there's clearly something rotten in Ankara, Turkey is not the only country whose reported cases fall well short of expected incidence. I may revisit this later.
COVID-19: Why US situation is far worse than Europe's, and why this may not be immediately evident
TL;DR: In assessing relative risk status, the future must be considered, not simply the present.
An HN thread[0] discusses whether the US or Europe are experiencing a worse Covid situation. The question contains nuances and pitfalls, though the general answer seems to be:
- The EU's situation is generally several weeks advanced relative to the US. As with the Jan--Mar 2020 interval, situations in different regions can be generally considered as time-shifts of one another rather than distinct dynamics.
- Instant measures of current case or death rates fail to account for built-in and likely future impacts and risks. Ignoring these is a category error, though a common one.
- The European daily trends are slowing or reversing. US trends are accelerating. The US future looks far bleaker than the European future. This contrasts with the blinding bias of considering only immediate present measures such as daily mortality.
Covid and population here come from Worldometers.
The thread begins with Aperocky's comment asserting, correctly, that "The worst hit place right now is the ~United States of America."
Responding, esja asserts "this is not true", though doesn't clarify their redefinition of "worst hit", for another two rounds of discussion, finally settling on "deaths today".
That basis is fatally (so to speak) flawed as it entirely dismisses the facts that:
Cases today translate directly to deaths in the 2--4 week future, at a best-case rate of 0.5% CFR and far more plausibly 1.5--3% CFR, based on present reported cases.[1]
US new cases per capita are at least on par if not worse than Europes's.
Europe's daily case rates are trending at worst flat, and are generally decreasing.
US case rates are rising, at an acellerating rate.
The US today reports 158,363 new cases (7-day average), and a 3% CFR. In ~2--3 weeks, likely daily deaths will be 2,375--4,750, or 7.5--15 per million.[2]
Germany, to use esja's favoured example, reports 18,363 new cases (7-day average), and a 2% CFR. In ~2--3 weeks, likely daily deaths will be 367--550, 4.4--6.6 per million.[3]
All Europe reports ~220,000 new daily cases (16 Nov 2020, not smoothed). in ~2--3 weeks, likely daily deaths will be 3,300--6,600, 4.4--8.8 per million.[4]
In all cases, baked-in future daily US mortality rates will be roughly twice those of Europe, adjusted for population and are trending still further worse. The US 'benefits' only by having begun its annual seasonal coronavirus peak some 4--8 weeks later than Europe, with an European inflection beginning in September--October and a US inflection beginning October--November.
To provide an analogy, esja is laughing at Europe being in a ditch whilst the US is racing toward a cliff's edge. Assessments of present health or wealth must include obvious future consequences or risks. Critics of EU response entirely ignore these, and reframe the initial criterion to do so.
Such analysis suffers from presentism and risk blindness and is utterly flawed.
Adapted from HN comments to the thread linked above.
Notes:
Beginning here: https://news.ycombinator.com/item?id=25113115
I'm ignoring the fact that reported fatalities undercount true COVID-19 fatalities as demonstrated by overall excess deaths by about 30% per an August 2020 New York Times report and other independent studies and data. This is a largely global bias, doesn't affect inter-regional comparisons, simplifies analysis, and strengthens my argument as the case I present, bleak as it is, is less severe than the actual reality
Using 1.5--3% CFR.
Also using 1.5%--35 CFR, despite Germany's lower experienced CFR.
Worldometers does not provide continental/regional plots or smoothed trends, though law-of-large-numbers helps somewhat. Again at 1.5--3% CFR, based on reported values, whic undercounts recoveries, experienced CFR is ~4%. Using a non-smoothed current high-point number further overstates total European future mortality relative to the US.
#covid19 #UnitedStates #europe #CriticalThinking #FlawedArguments #HackerNews #risk #worldometers
COVID-19: Texas has overtaken California for most cases to date
- TX: 889,513 (30,677/1M)
- CA: 888,305 (22,482/1M)
https://www.worldometers.info/coronavirus/country/us/
Again, days earlier than projected.
(I'm trying to lean conservative in forecasting.)
Texas, Illinois, and Wisconsin exceeded California's new-case count, Texas by more than double (6,414 vs. 3,047).
#covid19 #texas #california #worldometers #coronavirus #epidemiology
COVID-19: 40 million cases worldwide. We'll cross 50 million within a month
Via Worldometers.
Given the 7-day average of 358k cases/day, 50 million is 27 days away.
Given cases are increasing with no end in sight, likely nearer 25 days, possibly fewer.
Spain has joined the millionaires club, as I'd predicted six days ago, calling for the event within two weeks. Argentina and Columbia will do so within days.
The US will cross 9 million cases in about 10--12 days. Texas will surpass California soon. Daily case totals are higest in Illinois, though cases/1mm pop are ... probably highest in North Dakota (I'd need to calculate this).
India's daily count is above the US, though the two countries are trading places as US infection rates rise and India's fall.
COVID-19: Whilst you^†^ were distracted this past weekend ...
... Global officially reported^‡^ deaths have surpassed 1 million.
https://www.worldometers.info/coronavirus/
Notes:
† And by "you" I of course mean "I".
‡ Actual mortality is much higher, likely by 30--50%, or more."