The relationship between COVID-19 vaccination, partisan self-identification, and flu vaccine uptake: A structural equation modeling approach

The politicization of COVID-19 vaccination reduced COVID-19 vaccine uptake during the pandemic. In particular, people who identified with the Republican Party and those who reported lower trust in government reported lower COVID-19 vaccine uptake. Scholars expressed concern that the negative attitudes people developed toward COVID-19 vaccines will lead to a lowered uptake of other vaccines, particularly the flu vaccine. We developed an original survey to investigate the relationship between COVID-19 vaccine uptake, partisan self-identification, and flu uptake. Using registration-based random sampling, data were collected in March 2023 in South Dakota, a rural and socially and politically conservative state. We measured COVID-19 and flu vaccination status, trust in government, partisan self-identification, and various demographic variables. Associations between flu vaccination status and the variables discussed above were analyzed with mediation analysis through COVID-19 vaccine uptake using structural equation modeling. Since most variables were categorical, we used the weighted least squares option for estimation. Our sample consisted of 747 respondents. After accounting for control variables, our analysis revealed significant direct (standardized effect of 0.086, p=0.0071) and indirect (standardized effect of -0.201, p<0.0001) associations between partisan self-identification and flu vaccination. We also found significant indirect associations between trust in the federal government and flu vaccination (standardized effect of 0.196, p<0.0001). These observations were consistent with the associations in the literature and the hypothesized paths. The findings will likely be of interest to public health officials and clinicians as they seek to increase the public's confidence in the flu vaccine.