An Experimental Study on how Messaging from CDC Affects Attitudes toward Mandatory MMR Vaccination for Schoolchildren

During the COVID-19 pandemic, public health institutions, particularly the Centers for Disease Control and Prevention (CDC), were frequently attacked by politicians. Popular trust in these institutions declined, particularly among self-identified Republicans. Therefore, the effectiveness of public health institutions as vaccination messengers might have been weakened in the post-COVID-19 period. We conducted a survey experiment examining the effectiveness of messaging from the CDC in shaping people's attitudes toward mandatory MMR (measles-mumps-rubella) vaccination for schoolchildren.

The experiment was embedded in a survey fielded in South Dakota, a "red state" with a population predisposed to distrust the CDC. Using registration-sampling, we received 747 responses. We used difference-in-means tests and multivariate regression to analyze the data.

We found that participants who received a message from the CDC were more likely to support MMR vaccine mandate for schoolchildren than participants who received the same prompt from a state agency. Further analyses showed that messaging from the CDC was particularly effective among Republicans.

Overall, our study showed that although the CDC was caught up in the political skirmishes during the COVID-19 pandemic, it remains an authoritative source of public health information.

Public health officials at the local and state levels should not shy away from referring to the CDC in their vaccination messaging.