This study will deploy a multimodal pragmatic intervention to improve vaccine uptake in priority populations and address vaccine hesitancy to improve access by using a proactive organized population-based outreach leveraging health information technology with tailored navigation support to address mistrust and social barriers.

This study will deploy a multimodal pragmatic intervention to improve vaccine uptake in priority populations through a proactive organized population-based outreach approach. It will leverage health information technology with tailored navigation support to address mistrust and social barriers. Study key objectives are to:

1. conduct a survey of patients to assess and track barriers, intent, and sources of information on COVID vaccine over time.

2. Determine whether a primary care physician (PCP) endorsement with or without interactive digital communication plus navigation is more effective in promoting uptake of COVID-19 vaccine than general messages from the clinic. Patients will be randomized to one of three arms:

   1. Arm 1: Message about vaccine availability delivered by SMS advising patients to make an appointment.
   2. Arm 2: Same as Arm 1 but delivered as a personalized message text from the PCP.
   3. Arm 3: Same as Arm 2 plus a interactive 2-way SMS options.

Inclusion Criteria: 18 years and older, receiving care at Adelante Healthcare and not vaccinated or already scheduled for vaccination through the health center's appointment system Exclusion Criteria: Patient younger than 18 or who have been previously or are selected for vaccination during or prior to the week of study enrollment