At approximately 930 am, Offender was vaccinated in Housing Unit and returned to his bed. He was monitored by nursing staff for 15 minutes and had no adverse reaction or side effects. At approximately 1030am, Offender  was called to the officer's desk and was told to report to the visiting room for vaccination. Upon arrival, offender  was again vaccinated in the opposite arm. Offender was called in error rather than his room mate was who was an add on to the vaccination list. Offender was admitted to the Health Care Unit for observation for 24 hrs. Vital signs remained stable throughout this period with only a complaint of bilateral sore arms.  There were nono additional sequelae. Office of Health Services was notified of the incident on February 25, 2021 and began a review as part of our quality improvement process and in order to recommend practice modifications, provide education, implement policy change, monitor outcomes and prevent re-occurrence.  OHS reviewed information obtained from Moderna regarding the management of vaccine administration errors.  The error at facility is known as an "invalid dose".  In general there is limited information, yet low risk, for individuals who either receive a second dose within 21 days or a higher than authorized dose volume. The recommendations in this guidance related to the facility occurrence are summarized:  Second dose administered in < 21 days  Do not repeat dose. Higher than authorized dose volume administered  Do not repeat dose. *  Inform the recipient of the potential for local and systemic adverse.    Additional recommendations from the process:   1. Identity verification.  There were several opportunities for Health Care Staff, Security Staff, and  Guardsmen to confirm the identify of Offender. a. All offenders must wear their ID throughout all steps of the vaccination process.   b. Health Care Staff, Security Staff, andGuardsmen must verify offender identities as needed for their assignments throughout each step the vaccination process c. Health care staff must verify accurate completion of offender vaccination forms and ensure that forms match the offender being vaccinated.  d. Health care and Security staff must identify offenders by offender name and number rather than housing assignment. e. Use of handwritten lists should be minimized.  Other pre-printed available rosters or spreadsheets are preferable 2. Offender completed two sets of consent forms for vaccination.  It is unclear if he did not understand the process, or exactly why he would repeat the vaccination process.   a. Though language did not appear to be an issue, appropriate interpreters should be made available to obtain consents and provide education. b. When necessary consent forms should be provided in the native language spoken by the offender. c. It is unclear why there was no further attempt to confirm that Offender had previously received a vaccination that day, after stating that fact to those present before he received his second dose of vaccine. In the future, if an individual states that he or she has already been vaccinated the process must stop until his or her claims have been verified or shown to be false. 3. Any unplanned changes to the onsite vaccination plan (add-ons, extra dose redistribution, team deployment etc.) must be communicated to all members of the vaccination team.  4. Health care staff alone are responsible for the completion of all consent forms and vaccination documentation.   5. Identify best practices and standardize vaccination add-ons across facilities. Consider: location, addition to master vaccination roster, etc. a. Perhaps add-on vaccinations can be moved to another area for tracking. b. Add-ons should be added to the master vaccination roster.  Additional recommendations: 6. Re-Training on the vaccination protocol for health care, operations and national guard staff.    The above items were completed.