- any known mmr vaccine contraindication - fever - weakened resistance toward infections due to a disease in/of the immune system - individuals receiving medical treatment that affects the immune response or other immunosuppressive therapy in the last year (see excluded medications). - individuals with a congenital cellular immunodeficiency - individuals with a malignancy involving bone marrow or lymphoid systems - individuals with any serious underlying illness (such as malignancy). people with cardiovascular disease, hypertension, diabetes, and/or chronic respiratory disease are eligible if not immunocompromised (at the discretion of the id co-investigator) - individuals with known or suspected hiv infection, even if asymptomatic or has normal immune function. (due to the risk of disseminated mmr infection) - individuals with an active skin disease such as eczema, dermatitis or psoriasis at or near the site of vaccination. a different site can be chosen if necessary - pregnant or women who think they may test positive for pregnancy in this next month following mmr vaccine administration. - individuals who have received a mmr or another live vaccine (i.e., zostavax, nasal flu vaccine) within the last year - individuals with known anaphylactic reaction to any of the ingredients present in the mmr vaccine - individuals previously testing positive for sars-cov-2 or documented seropositive for sars-cov-2 antibodies prior to enrollment in this study

- any known mmr vaccine contraindication - fever - weakened resistance toward infections due to a disease in/of the immune system - individuals receiving medical treatment that affects the immune response or other immunosuppressive therapy in the last year (see excluded medications). - individuals with a congenital cellular immunodeficiency - individuals with a malignancy involving bone marrow or lymphoid systems - individuals with any serious underlying illness (such as malignancy). people with cardiovascular disease, hypertension, diabetes, and/or chronic respiratory disease are eligible if not immunocompromised (at the discretion of the id co-investigator) - individuals with known or suspected hiv infection, even if asymptomatic or has normal immune function. (due to the risk of disseminated mmr infection) - individuals with an active skin disease such as eczema, dermatitis or psoriasis at or near the site of vaccination. a different site can be chosen if necessary - pregnant or women who think they may test positive for pregnancy in this next month following mmr vaccine administration. - individuals who have received a mmr or another live vaccine (i.e., zostavax, nasal flu vaccine) within the last year - individuals with known anaphylactic reaction to any of the ingredients present in the mmr vaccine - individuals previously testing positive for sars-cov-2 or documented seropositive for sars-cov-2 antibodies prior to enrollment in this study