- 1. had previous sars-cov-2 infection (detected by either pcr, anti-s igg before the 1st vaccine dose, anti-n igg at any stage). 2. had an allergic response to any of the previous bnt162b2 doses. 3. has history of myopericarditis. 4. report that they do not feel well or have a fever on the day of vaccination. 5. pregnant on day of recruitment.

- 1. had previous sars-cov-2 infection (detected by either pcr, anti-s igg before the 1st vaccine dose, anti-n igg at any stage). 2. had an allergic response to any of the previous bnt162b2 doses. 3. has history of myopericarditis. 4. report that they do not feel well or have a fever on the day of vaccination. 5. pregnant on day of recruitment.