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. 2021 Sep:1:100019.
doi: 10.1016/j.lana.2021.100019. Epub 2021 Jul 13.

Estimating under-recognized COVID-19 deaths, United States, march 2020-may 2021 using an excess mortality modelling approach

A Danielle Iuliano  1   2   3 , Howard H Chang  4 , Neha N Patel  1   2   5 , Ryan Threlkel  1   2   6 , Krista Kniss  1   2 , Jeremy Reich  1   7 , Molly Steele  1   8 , Aron J Hall  1   8 , Alicia M Fry  1   2   3 , Carrie Reed  1   2
Affiliations

Estimating under-recognized COVID-19 deaths, United States, march 2020-may 2021 using an excess mortality modelling approach

A Danielle Iuliano et al. Lancet Reg Health Am. 2021 Sep.

Abstract

Background: In the United States, Coronavirus Disease 2019 (COVID-19) deaths are captured through the National Notifiable Disease Surveillance System and death certificates reported to the National Vital Statistics System (NVSS). However, not all COVID-19 deaths are recognized and reported because of limitations in testing, exacerbation of chronic health conditions that are listed as the cause of death, or delays in reporting. Estimating deaths may provide a more comprehensive understanding of total COVID-19-attributable deaths.

Methods: We estimated COVID-19 unrecognized attributable deaths, from March 2020-April 2021, using all-cause deaths reported to NVSS by week and six age groups (0-17, 18-49, 50-64, 65-74, 75-84, and ≥85 years) for 50 states, New York City, and the District of Columbia using a linear time series regression model. Reported COVID-19 deaths were subtracted from all-cause deaths before applying the model. Weekly expected deaths, assuming no SARS-CoV-2 circulation and predicted all-cause deaths using SARS-CoV-2 weekly percent positive as a covariate were modelled by age group and including state as a random intercept. COVID-19-attributable unrecognized deaths were calculated for each state and age group by subtracting the expected all-cause deaths from the predicted deaths.

Findings: We estimated that 766,611 deaths attributable to COVID-19 occurred in the United States from March 8, 2020-May 29, 2021. Of these, 184,477 (24%) deaths were not documented on death certificates. Eighty-two percent of unrecognized deaths were among persons aged ≥65 years; the proportion of unrecognized deaths were 0•24-0•31 times lower among those 0-17 years relative to all other age groups. More COVID-19-attributable deaths were not captured during the early months of the pandemic (March-May 2020) and during increases in SARS-CoV-2 activity (July 2020, November 2020-February 2021).

Interpretation: Estimating COVID-19-attributable unrecognized deaths provides a better understanding of the COVID-19 mortality burden and may better quantify the severity of the COVID-19 pandemic.

Funding: None.

Keywords: COVID-19; Excess mortality; Mortality; SARS-CoV-2; Unrecognized deaths.

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Conflict of interest statement

There were no conflicts of interest reported by authors.

Figures

Figure 1:
Figure 1
All-cause deaths after removing COVID-19 coded deaths, estimated expected deaths assuming SARS-CoV-2 circulation, predicted deaths accounting for circulation of SARS-CoV-2, and SARS-CoV-2 percent positive in United States by epidemiologic week for March 8, 2020—May 29, 2021 for all ages a COVID-19–attributable unrecognized deaths were calculated as the difference between predicted deaths accounting for SARS-CoV-2 circulation and expected deaths assuming no circulation of the virus. b Deaths reported in most recent weeks may still underestimate the total number of all-cause deaths after being corrected due to increases in deaths and delays in reporting during the pandemic.
Figure 2:
Figure 2
Death certificate reported and unrecognized COVID-19 deaths for all age groups by week from March 8, 2020—May 29, 2021 a Deaths reported in most recent weeks may still underestimate the total number of all-cause deaths after being corrected due to increases in deaths and delays in reporting during the pandemic.
Figure 3:
Figure 3
Unrecognized COVID-19–attributable death rates per 100,000 for all age groups by state from March 8, 2020—May 29, 2021
See this image and copyright information in PMC

References

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