Mandates Helped Control COVID in NYC Municipal Workers

A return-to-office policy did not increase cases of COVID-19 among New York City municipal employees while a vaccine mandate led to decreased cases and hospitalizations, reports a study in the March Journal of Occupational and Environmental Medicine.
Using NYC health data, the researchers analyzed the short-term impact of changes in pandemic policies on COVID-19 transmission and hospitalization rates among NYC municipal employees, compared to other working-age adults who lived in the City.
The research looked at the weeks before and after the lifting of a pandemic telework policy for NYC municipal employees on September 13, 2021. In the weeks before and after workers returned to the office, health data showed no significant change in COVID-19 incidence (diagnosis) rates among City employees, compared to non-municipal employees who lived in the City, according to the new research, led by Sharon K. Greene, PhD, MPH, of the NYC Health Department. In both groups, the COVID-19 case rate decreased by about 30% from before to after the policy change, as the Delta epidemic wave waned.
At the same time, NYC public schools reopened, ending a previous remote-learning policy. School reopening was followed by a 13% reduction in the COVID-19 case rate among DOE employees—significantly smaller than a 32% reduction among non-City employees. Thus, “Reopening public schools resulted in a relative increase in cases among DOE employees,” the researchers write.
Starting on October 29, 2021, all City employees were required to receive COVID-19 vaccination. Over the next 3 months through the first Omicron wave, municipal employees had an 8.5% smaller increase in COVID-19 case rate compared to non-City employees. The increase in COVID-19 hospitalization rate was also lower for municipal employees.
Return-to-office and COVID-19 vaccination mandates remain controversial, but few studies have assessed the real-world impact of these policies on transmission rates. The new findings in NYC employees—the largest municipal workforce in the United States—provide short-term evidence that a return-to-office policy and vaccine mandate were successful in minimizing COVID-19 case rates.
However, reopening public schools was linked to a short-term relative increase in cases among DOE employees. The study was conducted prior to expansions of COVID-19 vaccine eligibility to younger children and further upgrades in school ventilation systems. Dr. Greene comments, “These findings should be interpreted in broader context with other health, social, educational, and economic effects of the mandates and are an important contribution to the ongoing discussion around employee mandates, as workplaces adapt to COVID-19-related disruptions.”
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About the Journal of Occupational and Environmental Medicine
The Journal of Occupational and Environmental Medicine ( is the official journal of the American College of Occupational and Environmental Medicine. Edited to serve as a guide for physicians, nurses, and researchers, the clinically oriented research articles are an excellent source for new ideas, concepts, techniques, and procedures that can be readily applied in the industrial or commercial employment setting.


Greene SK; Tabaei BP; Culp GM; Levin-Rector A; Kishore N; Baumgartner J. Effects of return-to-office, public schools reopening, and vaccination mandates on COVID-19 cases among municipal employee residents of New York City. J Occup Environ Med. 2023;65(3):193-202.