Bozio, Catherine H.Grannis, Shaun J.Naleway, Allison L.Ong, Toan C.Butterfield, Kristen A.DeSilva, Malini B.Natarajan, KarthikYang, Duck-HyeRao, SuchitraKlein, Nicola P.Irving, Stephanie A.Dixon, Brian E.Dascomb, KristinLiao, I.-ChiaReynolds, SueMcEvoy, CharleneHan, JungmiReese, Sarah E.Lewis, NedFadel, William F.Grisel, NancyMurthy, KempapuraFerdinands, JillKharbanda, Anupam B.Mitchell, Patrick K.Goddard, KristinEmbi, Peter J.Arndorfer, JulieRaiyani, ChandniPatel, PalakRowley, Elizabeth A.Fireman, BruceValvi, Nimish R.Griggs, Eric P.Levy, Matthew E.Zerbo, OussenyPorter, Rachael M.Birch, Rebecca J.Blanton, LeneeBall, Sarah W.Steffens, AndreaOlson, NatalieWilliams, JeremiahDickerson, MonicaMcMorrow, MeredithSchrag, Stephanie J.Verani, Jennifer R.Fry, Alicia M.Azziz-Baumgartner, EduardoBarron, MichelleGaglani, ManjushaThompson, Mark G.Stenehjem, Edward2022-02-242022-02-242021-11Bozio, C. H., Grannis, S. J., Naleway, A. L., Ong, T. C., Butterfield, K. A., DeSilva, M. B., Natarajan, K., Yang, D.-H., Rao, S., Klein, N. P., Irving, S. A., Dixon, B. E., Dascomb, K., Liao, I.-C., Reynolds, S., McEvoy, C., Han, J., Reese, S. E., Lewis, N., … Stenehjem, E. (2021). Laboratory-Confirmed COVID-19 Among Adults Hospitalized with COVID-19–Like Illness with Infection-Induced or mRNA Vaccine-Induced SARS-CoV-2 Immunity—Nine States, January–September 2021. MMWR. Morbidity and Mortality Weekly Report, 70(44), 1539–1544. https://doi.org/10.15585/mmwr.mm7044e10149-2195, 1545-861Xhttps://hdl.handle.net/1805/27933What is already known about this topic? Previous infection with SARS-CoV-2 or COVID-19 vaccination can provide immunity and protection against subsequent SARS-CoV-2 infection and illness. What is added by this report? Among COVID-19–like illness hospitalizations among adults aged ≥18 years whose previous infection or vaccination occurred 90–179 days earlier, the adjusted odds of laboratory-confirmed COVID-19 among unvaccinated adults with previous SARS-CoV-2 infection were 5.49-fold higher than the odds among fully vaccinated recipients of an mRNA COVID-19 vaccine who had no previous documented infection (95% confidence interval = 2.75–10.99). What are the implications for public health practice? All eligible persons should be vaccinated against COVID-19 as soon as possible, including unvaccinated persons previously infected with SARS-CoV-2.en-USCC0 1.0 Universal (CC0 1.0)SARS‐CoV2Covid-19COVID-19 Vaccinelaboratory-confirmed COVID-19unvaccinated adultsvaccinated recipientsArticle