I have recommended to my wife and two adult sons to opt for Moderna after receiving 1sr dose of Pfizer (unavailable this week). Mixing works and it is safe to do so. End result = protection #vaccineswork #protectyourfamilywithscience June 21, 2021June 21, 2021Dr. Barry Dworkin Medical Mythbusting Commentary for June 21, 2021 [display_podcast] Source:Ottawa’s COVID-19 vaccine clinics will only offer Moderna doses to adults this week due to delayed Pfizer shipment Related posts: Will Covid vaccine mixing be adopted as health policy? They use different delivery systems carrying the genetic instruction set to produce the same spike protein, ergo ongoing studies are evaluating clinical outcomes to determine if assumption is true. What should your #seconddose of #covidvaccine be if 1st was AZ? Factors include wait-time/availability, Delta variant prevalence, occupational risks, and study evidence. Answer seems to leaning to Pfizer or Moderna as 2nd dose of choice. NACI recommends second dose Pfizer/moderna vaccine for those who had AZ as their first dose. Latest CDC data indicates that COVID is rapidly becoming a disease of the unvaccinated. #VaccinesWork #GoScience modernaPfizervaccine mixing