Liu, X., Munro, A. P. S., Feng, S., Janani, L., Aley, P. K., Babbage, G., …the COV-BOOST study group. (2022). Persistence of immunogenicity after seven COVID-19 vaccines given as third dose boosters following two doses of ChAdOx1 nCov-19 or BNT162b2 in the UK: Three month analyses of the COV-BOOST trial. Journal of Infection, 84(6), 795-813. https://doi.org/10.1016/j.jinf.2022.04.018