Fast Five Quiz: mRNA Vaccinations

Enrico Brunetti, MD


April 14, 2023

Research on vaccines against viral pathogens has shown that individuals who are immunocompromised do not mount the same response to vaccinations as do immunocompetent individuals. For example, immunogenicity studies suggest that the majority of solid organ transplant recipients did not mount a significant antibody response following the first dose of the mRNA COVID-19 vaccine. In one study, only 25% of kidney transplant recipients had detectable antibodies after full mRNA vaccination. However, for well-controlled patients with HIV, vaccine response appears to be nearly equivalent to that of healthy controls, and more than 80% of those with autoimmune disease or solid tumors may be seropositive after vaccination.

Risk factors of mRNA vaccine failure include use of immunosuppressive medications, anti-CD20 monoclonal antibodies, and radiation therapy. A 2022 study determined that "recent antibiotic use may be associated with a lower seroconversion rate at day 21 (but not day 56 or 180)." However, more research is needed to determine whether the use of antibiotics affects efficacy at the time of mRNA vaccination.

Studies involving sex differences in the efficacy and safety of COVID-19 vaccination note that males and females can experience different immune responses and side effects, but sex does not typically negatively affect mRNA vaccination efficacy.

Prior infection has been shown to enhance protection from mRNA vaccination.

Learn more about mRNA vaccination efficacy.


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