Abstract Coronavirus disease 2019 (COVID‐19) is an ongoing pandemic, which affected
around 45 million confirmed cases of COVID‐19, including more than 6 million deaths …

Abstract Coronavirus Disease 2019 (COVID-19) has been the most severe public health
challenge in this century. Two years after its emergence, the rapid development and …

Background The safety and immunogenicity of the bivalent omicron-containing mRNA-
1273.214 booster vaccine are not known. Methods In this ongoing, phase 2–3 study, we …

Background Early treatment to prevent severe coronavirus disease 2019 (Covid-19) is an
important component of the comprehensive response to the severe acute respiratory …

Vaccine effectiveness (VE) against COVID-19–associated emergency department/urgent
care (ED/UC) visits and hospitalizations was higher after the third dose than after the second …

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron (B. 1.1. 529)
variant is highly transmissible with potential immune escape. We conducted a test-negative …

Objectives To characterize the clinical severity of covid-19 associated with the alpha, delta,
and omicron SARS-CoV-2 variants among adults admitted to hospital and to compare the …

Abstract Background On January 2, 2022, Israel began administering a fourth dose of
BNT162b2 vaccine to persons 60 years of age or older. Data are needed regarding the …

Trends in Disease Severity and Health Care Utilization During the Early Omicron Variant Period
Compared with Previous SARS-CoV-2 High Transmission Periods — United States, December …

Background Infants younger than 6 months of age are at high risk for complications of
coronavirus disease 2019 (Covid-19) and are not eligible for vaccination. Transplacental …