JMIR Publications

ABSTRACT

Background:

Vaccines are essential public health interventions, yet they remain controversial, with individuals expressing differing views about their risks, benefits, and acceptance. Social media platforms provide large amounts of publicly available data that can be used to examine public perceptions and concerns regarding vaccination. Comparing discussions of mandatory and voluntary vaccines may provide insight into the factors shaping online vaccine-related discourse.

Objective:

This study aimed to examine and compare online discussions of a mandatory vaccine, the measles, mumps, and rubella (MMR) vaccine, and a voluntary vaccine, the influenza (flu) vaccine, using text analysis of Reddit discussions.

Methods:

Publicly available Reddit data were collected in May 2020. Initial Reddit threads containing “MMR vaccine” or “measles, mumps, and rubella vaccine” in the title were collected for the MMR vaccine, while threads containing “flu vaccine” or “influenza vaccine” in the title were collected for the flu vaccine. All replies to the identified initial posts were subsequently collected. The final dataset comprised 11,176 MMR vaccine-related posts and 10,152 flu vaccine-related posts. Descriptive and text analysis techniques were used to characterize and compare discussions concerning the two vaccine types, including patterns of interaction, post scores, and major topics of discussion.

Results:

The MMR vaccine dataset contained 11,176 posts, compared with 10,152 posts in the flu vaccine dataset. MMR vaccine-related discussions generated more comments than discussions concerning the flu vaccine. MMR-related posts also had a higher average Reddit post score than flu vaccine-related posts. Text analysis indicated that discussions about mandatory MMR vaccination were more interactive and focused primarily on risks associated with vaccination. In contrast, discussions concerning voluntary flu vaccination focused more strongly on vaccine effectiveness and individual decisions about whether to receive the vaccine. Statistical significance measures, including P values and confidence intervals, were not available from the provided study information.

Conclusions:

Online discussions differ according to whether a vaccine is mandatory or voluntary. Discussions of the MMR vaccine were characterized by greater interaction and greater emphasis on vaccination-related risks, whereas discussions of the flu vaccine focused more on effectiveness and individual vaccination decisions. These findings demonstrate the potential of Reddit data and text analysis to identify vaccine-specific public concerns and may help health agencies, healthcare providers, caregivers, and researchers develop more targeted approaches to vaccine communication and education.