As Covid-19 sweeps across the U.S., New York City has been hit particularly hard, with nearly 20,000 confirmed and probable Covid-19-associated deaths as of May 2; however, according to a report from the New York City Department of Health and Mental Hygiene (DOHMH) Covid-19 Response Team published in the CDC’s Morbidity and Mortality Weekly Report, the pandemic’s actual death toll might be much higher.
“Counting only confirmed or probable Covid-19–associated deaths… likely underestimates the number of deaths attributable to the pandemic,” wrote Donald R. Olson and colleagues from the DOHMH Covid-19 Response Team. “The counting of confirmed and probable Covid-19–associated deaths might not include deaths among persons with SARS-CoV-2 infection who did not access diagnostic testing, tested falsely negative, or became infected after testing negative, died outside of a health care setting, or for whom Covid-19 was not suspected by a health care provider as a cause of death. The counting of confirmed and probable Covid-19–associated deaths also does not include deaths that are not directly associated with SARS-CoV-2 infection.”
Olson and colleagues set out to provide an estimate of all-cause excess deaths — “the number of deaths above expected seasonal baseline levels, regardless of the reported cause of death” — that have occurred in New York City since the beginning of widespread community transmission of SARS-CoV-2 in an attempt to “provide a more accurate measure of the impact of the pandemic,” they wrote.
To estimate excess deaths in New York City over the course of the pandemic, Olson and colleagues used data from DOHMH’s electronic vital statistics reporting system using a seasonal periodic regression model, the same method the group typically uses to monitor seasonal flu impact. “Excess deaths were determined for the period March 11–May 2, 2020, using mortality data from the period January 1, 2015–May 2, 2020 and calculated as the difference between the seasonally expected baseline number and the reported number of all-cause deaths,” they explained.
During the period of March 11-May 2, 2020, DOHMH received reports of 32,107 deaths — of these, 24,172 (95% CI, 22,980-25,364) were “found to be in excess of the seasonal expected baseline,” they found. “Included in the 24,172 deaths were 13,831 (57%) laboratory-confirmed Covid-19–associated deaths and 5,048 (21%) probable Covid-19–associated deaths, leaving 5,293 (22%) excess deaths that were not identified as either laboratory-confirmed or probable Covid-19–associated deaths.”
Olson and colleagues noted that, while there is not a direct causal link between these 5,293 additional deaths and the virus itself, they still might have been directly or indirectly attributable to the Covid-19 pandemic.
“Covid-19–associated mortality is higher in persons with underlying chronic health conditions such as heart disease and diabetes, and deaths in persons with these chronic health conditions might not be recognized as being directly attributable to Covid-19,” they wrote. “In addition, social distancing practices, the demand on hospitals and health care providers, and public fear related to Covid-19 might lead to delays in seeking or obtaining lifesaving care. Thus, monitoring of all-cause deaths and estimating excess mortality during the pandemic provides a more sensitive measure of the total number of deaths than would be recorded by counting laboratory-confirmed or probable Covid-19–associated deaths.”
Olson and colleagues argued that surveillance of all-cause mortality offered a “faster and more inclusive measure of the pandemic’s impact on mortality than does relying only on national Covid-19 reporting mechanisms.”
John McKenna, Associate Editor, BreakingMED™
Cat ID: 125
Topic ID: 79,125,730,933,125,190,520,926,192,927,151,928