LAUSR

BACKGROUND Throughout the COVID-19 pandemic, U.S. Centers for Disease Control and Prevention policies on face mask usage fluctuated. Understanding how public health communications evolve around key policy decisions may inform future decisions around preventative measures by aiding the design of communication strategies (e.g., wording, timing, channel) that ensure rapid dissemination and maximize both widespread adoption and sustained adherence. OBJECTIVE Assess how mask sentiment evolved surrounding two changes to mask guidelines: (1) recommendation for mask usage on April 3, 2020 and (2) relaxation of mask usage on May 13, 2021. METHODS Interrupted time series methods were applied to U.S. Twitter data surrounding each guideline change. Outcomes were changes in the (1) proportion of positive, negative, and neutral tweets and (2) number of words within a tweet tagged with a given emotion (e.g., trust). Results were compared to COVID-19 Twitter data without mask keywords for the same period. RESULTS There were fewer neutral mask-related tweets in 2020 (β = -3.94 percentage points, 95% CI: -4.68, -3.21, P < .001) and 2021 (β = -8.74, 95% CI: -9.31, -8.17, P < .001). Following the April 3rd recommendation (β = 0.51, 95% CI: 0.43, 0.59, P < .001) and May 13th relaxation (β = 3.43, 95% CI: 1.61, 5.26, P < .001), the percent of negative mask-related tweets increased. The amount of trust-related terms decreased following the policy change on April 3 (β = -0.004, 95% CI: -0.004, -0.003, P < .001) and May 13 (β = -0.001, 95% CI: -0.002, 0, P = .008). CONCLUSIONS The U.S.-Twitter population responded negatively and with less trust following guideline shifts related to masking, regardless of whether the guidelines recommended or relaxed mask usage. Federal agencies should ensure that changes in public health recommendations are communicated concisely and rapidly.