Behavioral and psychosocial factors associated with coadministration of COVID-19 and influenza vaccines among the elderly.

BACKGROUND

Health authorities recommend adults aged 65 years and older receive COVID-19 and influenza vaccines at the same visit to improve vaccine uptake in this high-risk group. However, it remains unclear how widely older adults have accepted this recommendation in practice.

METHODS

Using data from the Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission, we examined coadministration uptake and factors associated with its acceptance among 2,860 community-dwelling Korean adults aged 65 years or older who received the 2023-2024 influenza vaccine. Verified vaccination and infection records from the Korea Disease Control and Prevention Agency were linked with survey responses on psychological antecedents of COVID-19 vaccination. Vaccination behavior was categorized as coadministration, separate visit vaccination, or influenza-only vaccination.

RESULTS

Overall, 15.0% received both vaccines at the same visit, while 43.3% received them on separate days. Prior receipt of both vaccines was the strongest predictor of coadministration (OR, 2.59; 95% CI, 1.70-3.95). Higher confidence in COVID-19 vaccination (OR, 1.30; 1.12-1.50) and lower complacency (OR, 0.81; 0.73-0.91) were associated with coadministration uptake.

CONCLUSIONS

These findings highlight the need for targeted efforts to build trust and communicate the safety and convenience of coadministration to improve uptake among older adults.