biostudies-literatureUnknown379Ferdinands JMNational Center for Immunization and Respiratory Diseases<h4>Objective</h4>To estimate the effectiveness of mRNA vaccines against moderate and severe covid-19 in adults by time since second, third, or fourth doses, and by age and immunocompromised status.<h4>Design</h4>Test negative case-control study.<h4>Setting</h4>Hospitals, emergency departments, and urgent care clinics in 10 US states, 17 January 2021 to 12 July 2022.<h4>Participants</h4>893 461 adults (≥18 years) admitted to one of 261 hospitals or to one of 272 emergency department or 119 urgent care centers for covid-like illness tested for SARS-CoV-2.<h4>Main outcome measures</h4>The main outcome was waning of vaccine effectiveness with BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine during the omicron and delta periods, and the period before delta was dominant using logistic BMJ (Clinical research ed.)e072141https://www.ebi.ac.uk/biostudies/studies/S-EPMC9527398biostudies-literatureWaning of vaccine effectiveness against moderate and severe covid-19 among adults in the US from the VISION network: test negative, case-control study.PMC9527398Rao SDixon BEGriggs EPLink-Gelles RWilliams JEmbi PJNaleway ALDascomb KMurthy KIrving SAStenehjem EOng TCGoddard KGaglani MPatel PRaiyani CThompson MGNatarajan KBozio CHFerdinands JMGrannis SJLiao ICArndorfer JDickerson MMcEvoy CGrisel NBarron MABlanton LLewis NFadel WFValvi NRYang DHKlein NPMitchell PKFireman BHan JReese SEDeSilva MBZerbo OBirch RfalseWaning of vaccine effectiveness against moderate and severe covid-19 among adults in the US from the VISION network: test negative, case-control study.<h4>Objective</h4>To estimate the effectiveness of mRNA vaccines against moderate and severe covid-19 in adults by time since second, third, or fourth doses, and by age and immunocompromised status.<h4>Design</h4>Test negative case-control study.<h4>Setting</h4>Hospitals, emergency departments, and urgent care clinics in 10 US states, 17 January 2021 to 12 July 2022.<h4>Participants</h4>893 461 adults (≥18 years) admitted to one of 261 hospitals or to one of 272 emergency department or 119 urgent care centers for covid-like illness tested for SARS-CoV-2.<h4>Main outcome measures</h4>The main outcome was waning of vaccine effectiveness with BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine during the omicron and delta periods, and the period before delta was dominant using logistic 2022-01-01T00:00:00Z2022 Oct2025-05-29T22:29:43.313Z2025-05-29T22:29:43.313ZS-EPMC95273983619194810.1136/bmj-2022-072141