Willingness to receive an annual COVID-19 booster vaccine in the German-speaking D-A-CH region in Europe: A cross-sectional study

Background Emergence of new coronavirus variants and waning immunity may necessitate regular COVID-19 vaccine boosters, but empirical data on population willingness for regular vaccination are limited. Methods In August 2021, we surveyed 3,067 quota-sampled German-speaking adults residing in the D-A-CH region (Germany, Austria, Switzerland). Using multivariable adjusted ordered logistic regression models we calculated odds ratios (OR) and 95% confidence intervals (95% CIs) to assess factors associated with willingness to vaccinate annually against COVID-19. Findings Among 2,480 participants vaccinated or planning to get vaccinated, 82.4% indicated willingness to receive annual COVID-19 boosters. This willingness was higher in Austria (OR=1.47, 95% CI, 1.19-1.82; p <0.001) and Germany (OR=1.98, 95% CI, 1.60-2.45; p <0.001) versus Switzerland and increased with age. Having voted in the last national election (ORopposition party voters = 1.51, 95% CI=1.18-1.92; p = 0.01 and ORgoverning party voters = 1.57, 95% CI=1.28-1.93; p < 0.001, versus non-voters) and not regularly participating in religious meetings (OR=1.37, 95% CI=1. 08-1.73; p = 0.009, versus participation at least monthly) were significantly associated with willingness to vaccinate, as was partial (OR=1.97, 95% CI=1.43-2.72; p < 0.001) or total (OR=5.20, 95% CI=3.76-7.19; p < 0.001) approval of COVID-19 mitigation measures (versus non-approval). By country, Austrians showed the strongest association of voting behavior and mitigation measure approval with willingness to vaccinate. Interpretation Targeted promotion programs informed by political and religious engagement and mitigation measure approval are needed to increase willingness to receive regular COVID-19 boosters. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd.