April 2022: Pre-print article published on preprints with The Lancet investigates the waning effectiveness of booster vaccines from Pfizer BioNTech (BNT162b2) and Oxfrord-AstraZeneca (ChadOx1), against symptomatic infection and severe COVID-19 in Brazil and Scotland. Waning of mRNA Boosters after Homologous Primary Series with BNT162b2 or ChadOx1 Against Symptomatic Infection and Severe COVID-19 in Brazil and Scotland: A Test-Negative Design Case-Control Study Cerqueira-Silva, T.; Shah, S.A.; Robertson, C.; Sanchez, M. N.; et. al. Pre-prints with the Lancet Published online on: 14 April 2022 Available at: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4082927 Note This is article has since been peer reviewed. Read the summary of the peer reviewed article This article was published on 2024-09-24