Designing and evaluating a technology-based intervention to address deep ambivalence about COVID vaccination among people who inject drugs

To encourage people who inject drugs to vaccinate against COVID-19, our research team collaborated with a harm reduction organization in East Harlem to create a multilevel, technology-based intervention that combined a brief (<6 minute) educational video with pre-post-test items measuring the likelihood of vaccination, attitudes, and vaccine-related heath literacy. A total of 545 participants completed the intervention; 45 vaccinated at the end of their first study visit. The remaining 500 were randomly assigned to two groups that were sent different text message configurations to examine which more effectively encouraged follow-up vaccination. The intervention group received Multimedia Messaging Service text messages featuring combinations of words and images, similar to frames of a graphic novel; the control group received Short Message Service texts consisting solely of words. Among those who did not vaccinate at first visit, 26 (7 intervention group and 19 control) vaccinated at follow-up. Greater vaccine-related knowledge (e.g. the vaccine does not contain a live virus) and positive vaccine attitudes were significantly associated with post intervention vaccination. Misinformation and misconceptions (i.e. vaccines are population control; vaccination is only for people who are already sick) emerged as powerful barriers to vaccination. Further research is warranted to address other forms of vaccine hesitancy among additional high-risk populations.