Billions of doses of coronavirus disease 2019 (COVID-19) vaccines have been administered
globally, dramatically reducing severe acute respiratory syndrome coronavirus 2 (SARS …

The coronavirus disease 2019 (COVID-19) pandemic has threatened global health and
prompted the need for mass vaccination. We aimed to assess the efficacy and effectiveness …

SARS-CoV-2 variants of concern (VOC) are more transmissible and may have the potential
for increased disease severity and decreased vaccine effectiveness. We estimated the …

Background The increasing incidence of pediatric hospitalizations associated with
coronavirus disease 2019 (Covid-19) caused by the B. 1.617. 2 (delta) variant of severe …

Background The effectiveness of heterologous prime-boost Coronavirus disease 2019
(Covid-19) vaccination is currently unknown. Methods From individuals vaccinated with two …

Background: As SARS-CoV-2 vaccination coverage increases in the United States (US),
there is a need to understand the real-world effectiveness against severe Covid-19 and …

Phase 3 randomized-controlled trials have provided promising results of COVID-19 vaccine
efficacy, ranging from 50 to 95% against symptomatic disease as the primary endpoints …

Background As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination
coverage increases in the United States, there is a need to understand the real-world …

Data on real-life vaccine effectiveness (VE), against the delta variant (B. 1.617. 2) of the
severe acute respiratory syndrome coronavirus 2 among various coronavirus disease 2019 …

Background Efficacy of vaccines studied in clinical trial settings are likely to be different from
their effectiveness in a real-world scenario. Indian Armed Forces launched its vaccine drive …