Kadali, Renuka Ananth KalyanJanagama, RavaliYedlapati, Siva H.Kanike, NeelakantaGajula, ViswanathMadathala, Rajasekhar R.Poddar, SwatiSukka, NeelakantaJogu, Hanumantha R.Racherla, ShailajaShah, Isha2022-02-242022-02-242022-01Kadali, R. A. K., Janagama, R., Yedlapati, S. H., Kanike, N., Gajula, V., Madathala, R. R., Poddar, S., Sukka, N., Jogu, H. R., Racherla, S., & Shah, I. (2022). Side effects of messenger RNA vaccines and prior history of COVID-19, a cross-sectional study. American Journal of Infection Control, 50(1), 8–14. https://doi.org/10.1016/j.ajic.2021.10.01701966553https://hdl.handle.net/1805/27937Background There are concerns regarding immunogenicity with coronavirus disease 2019 (COVID-19) mRNA vaccines among persons with prior history of COVID-19 (PHC). This study was to analyze the short-term side effects of mRNA vaccines among health care workers (HCWs) with and without PHC. Methods A cross-sectional study was performed using an independent online survey questionnaire that gathered responses from HCWs. Results Among 1,475 HCWs, 1268 (85.97%) completed the survey, 102/1268 (44/447 in Moderna group and 58/821 in Pfizer-BioNTech group) reported PHC during pre-vaccination period. Symptoms of flushing/P = .05, brain fogging/P= .005, vertigo/P= .041, numbness/P= .023, diarrhea/P= .047, hives/P= .028, itching/P= .028, swelling of lips/mouth/P= .001, shortness of breath/P= .022, and anxiety/P= .048 have greater occurrence among Pfizer-BioNtech group with PHC when compared to Pfizer-BioNtech group with no PHC. Symptoms of chills/P= .027, flushing/P= .045, tremor/P= .05, muscle spasm/P= .039, vomiting/P= .031, diarrhea/P= .015, and cough/P= .011 have higher occurrence among Moderna group with PHC when compared to Moderna group with no PHC. Conclusions Few short-term side effects among mRNA vaccine recipients with PHC may have necessitated transient time-off from work. The PHC can be considered as a predictor for severity of side effects. While the vaccination program continues in the United States, a future COVID legislation that mandates vaccination among employees along with paid time off provision may help with higher compliance and acceptance.en-USAttribution-NonCommercial-NoDerivatives 4.0 InternationalPrior infectionSARS-CoV-2ModernaPfizer-BioNtechPredictorslegislationArticle