Relationship between Influenza Vaccination Uptake and COVID-19 Death Rate in New York City Population

Abstract: Background: Influenza vaccination has been postulated to mitigate COVID-19 severity and may be an effective prevention measure to mitigate the pandemic. The aim of this ecological study was to assess the area-level relationship between cumulative death rate for COVID-19 and historic influenza vaccination uptake in the New York City population. Methods: Predictors of COVID-19 death included self-reported flu vaccination in 2018, as well as four CDC-defined risk factors of severe COVID-19 infection available at the ecological level, which were diabetes, asthma, BMI 30-100 (mg/k²) and hypertension. We used publicly available data from the NYC Department of Health Coronavirus repository and survey data from the Community Health Survey . COVID-19 death rate according to modified zip code tabulation areas (MODZCTA) was the outcome for multilinear analysis. Results: At univariate analysis, the rate of COVID-19 deaths deceased by 5.869 units for every one-unit increase in flu vaccination uptake for each zip-code area (p < .0001). In the multilinear model, predictors accounted for 23% of the variability in the COVID-19 death rate (p < .0001). After adjustment for all available risk factors, influenza vaccination and diabetes prevalence were significant predictors of COVID-19 deaths (B_adj = -4.217, p = 0.0024; B_adj = 8.867, p = 0.0051 for vaccination and diabetes, respectively). Conclusions: Differences in COVID-19 mortality have been documented across New York City. Modified zip codes with a higher prevalence of influenza vaccination had lower rates of COVID-19 mortality, inciting the need to further explore the relationship between influenza vaccination uptake and COVID-19 mortality at the individual level.