Covid-19 Fatalities and Excess Fatalities

The most recent “excess fatality” count remains solidly in the positive region, despite the severe under-reporting bias in the most recent observations. To see this, consider the most recent estimates for each of the previous vintages of “excess fatalities” calculated as actual-expected.

Figure 1: Excess fatalities, 10/21 vintage (chartreuse), 10/7 vintage (purple red), 9/30  vintage (violet), 9/23 vintage (chartreuse), 9/16 vintage (red), 9/9 vintage (green), 9/2 vintage (orange), 8/25 vintage (blue). Note excess fatalities differ from CDC series which are bounded below at zero. Source: CDC , various vintages, and author’s calculations.

This pattern suggests to me we should take with circumspection (1) the most recent counts of excess fatalities as they are likely to be revised substantially upward; and (2) administrative counts, either from CDC or from alternative compilations, as they are possibly missing many actual Covid-19 related deaths. Extending point (1), it is likely that excess fatalities were indeed falling for some time in August, but are possibly rising again given the size of the revisions in recent weeks’ data (The Economist has a discussion of excess fatalities around the world; the Excess Death Tracker is here.)

Here are the various series of interest, latest available.

Figure 2:  Weekly fatalities due to Covid-19 as reported to CDC for weeks ending on indicated dates (black), excess fatalities calculated as actual minus expected (teal), fatalities as tabulated by Our World in Data (dark red). Note excess fatalities differ from CDC series which are bounded below at zero. Light green shading denotes CDC data that are likely to be revised. Source: CDC  10/21/2020 vintage, OurWorldinData version of 10/22 accessed 10/22/2020 and author’s calculations.

One conclusion that seems obvious: Cumulative excess fatalities through week ending 8/25 are substantially higher than administratively defined Covid-19 cumulative fatalities.

Woolf et al. (JAMA, October 12, 2020) reports that March through July (ex-CT, NC):

Of the 225 530 excess deaths, 150 541 (67%) were attributed to COVID-19. Joinpoint analyses revealed an increase in deaths attributed to causes other than COVID-19, with 2 reaching statistical significance. US mortality rates for heart disease increased between weeks ending March 21 and April 11 (APC, 5.1 [95% CI, 0.2-10.2]), driven by the spring surge in COVID-19 cases. Mortality rates for Alzheimer disease/ dementia increased twice, between weeks endingMarch 21 and April 11 (APC, 7.3 [95% CI, 2.9-11.8]) and between weeks ending June 6 and July 25 (APC, 1.5 [95% CI, 0.8-2.3]), the latter coinciding with the summer surge in sunbelt states.

Discussion | Although total US death counts are remarkably consistent from year to year, US deaths increased by 20% during March-July2020.COVID-19was a documented cause of only 67% of these excess deaths. Some states had greater difficulty than others in containing community spread, causing protracted elevations in excess deaths that extended into the summer. US deaths attributed to some noninfectious causes increased during COVID-19 surges. Excess deaths attributed to causes other than COVID-19 could reflect deaths from unrecognized or undocumented infection with severe acute respiratory syndrome  coronavirus2ordeaths among uninfected patients resulting from disruptions produced by the pandemic. Study limitations include the reliance on provisional data, inaccuracies in death certificates, and assumptions applied to the model.

225530 excess fatalities reported by Woolf et al. for this period exceeds the 221848 in the CDC estimates I’m reporting above.