Assessing influenza vaccination success to inform COVID-19 vaccination campaign

Given recent downward trends in daily rates of COVID-19 vaccinations, it is important to reassess strategies to reach those most vulnerable. The success and efficacy of vaccination campaigns for other respiratory illnesses, such as influenza, may help inform messaging around COVID-19 vaccinations. This cross-sectional study examines the individual-level factors associated with, and the spatial distribution of, predictors of COVID-19 severity, and uptake of influenza and hepatitis B (as a negative control) vaccines across NYC. Data were obtained from the 2018 Community Health Survey (CHS), including self-reported influenza and hepatitis B vaccine uptake, diabetes, asthma, hypertension, body mass index (BMI), age, race/ethnicity, educational attainment, borough, and United Hospital Fund (UHF) neighborhood of residence. A CDC-defined COVID-19 severity risk score was created with variables available in the CHS, including diabetes, asthma, hypertension, BMI ≥ 30 kg/m² , and age ≥65 years old. After adjustment, there was a significant positive association between COVID-19 severity risk score and influenza vaccine uptake (1: OR_adj  = 1.49, 95% CI 1.28-1.73; 2: OR_adj  = 1.99; 95% CI: 1.65-2.41; 3+: OR_adj  = 2.89; 95% CI: 2.32-3.60, compared to 0). Hepatitis B vaccine uptake was significantly inversely associated with COVID-19 severity risk score (1: OR_adj  = 0.67; 95% CI: 0.57-0.79; 2: OR_adj  = 0.54; 95% CI: 0.44-0.66; 3+: OR_adj  = 0.45; 95% CI: 0.36-0.56, compared to 0). The influenza vaccination campaign template is effective at reaching those most at risk for serious COVID-19 and, if implemented, may help reach the most vulnerable that have not yet been vaccinated against COVID-19.