From the Document: "COVID-19 [coronavirus disease 2019] vaccines have been widely viewed as a means of reducing the spread of COVID-19 and facilitating a return to work and school. In general, for COVID-19 vaccines to effectively reduce disease transmission, a large percentage of the population must be vaccinated. This includes anyone who resides in the United States regardless of their authorization to do so. This Insight covers the distribution of COVID-19 vaccine to unauthorized immigrants (sometimes referred to as 'undocumented') in the United States--a population that may face barriers to vaccine access."
CRS Insight, IN11617
Congressional Research Service: https://crsreports.congress.gov/