The trusted messenger patient intervention will involve training a small number of staff "trusted messengers" to engage patients informally and assist with building vaccine confidence in brief one- on-one sessions, supported by trusted messengers weekly consultations with a content expert who can answer specific vaccine related questions that patients have over a 3-week period. Trusted messengers will be full time unit employees, selected with the assistance of the nursing supervisor for having excellent rapport with patients (assessed with the Nurse Coordinator Questionnaire) and for having been vaccinated. Mental health workers or nurses may serve in this role. Both inpatient units involved in this study will be grouped into the same vaccination cohort within the hospital, to provide patients in the intervention and the wait list similar opportunities to be vaccinated.

After a 3-week study period, up to 24 patients on the second unit will receive the trusted messenger intervention and followed for a period of 3 weeks. The trusted messenger intervention will consist of staff who are trained to engage patients informally and assist building social norms for vaccine uptake supported by weekly and as-needed check-ins with a content expert who can answer specific vaccine related questions over a 3 week period.

A nested waitlist design in which patients and staff are nested within two inpatient psychiatric units. New Hampshire Hospital staff will be trained to deliver the trusted messenger intervention up to 24 patients on the first unit while the second unit receives care as usual, during which time in-house vaccinations among patients on both units will be tracked in a registry. After a 3-week study period, up to 24 patients on the second unit will receive the trusted messenger intervention and followed for a period of 3 weeks. The trusted messenger intervention will consist of staff who are trained to engage patients informally and assist building social norms for vaccine uptake supported by weekly and as-needed check-ins with a content expert who can answer specific vaccine related questions over a 3 week period.

The participant is willing to receive the COVID-19 vaccine