Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new beta coronavirus
that emerged at the end of 2019 in the Hubei province of China. SARS-CoV-2 causes …

The emergence of several new variants of severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) in recent months has raised concerns around the potential impact on …

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

Developing safe and effective vaccines against severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2) at a breakneck speed has been an exceptional human …

Billions of doses of COVID-19 vaccines have been administered globally, dramatically
reducing SARS-CoV-2 incidence and severity in some settings. Many studies suggest …

Recently, Covid-19 vaccine effectiveness has decreased especially against mild disease
due to emergence of the Delta variant and waning protection. In this register-based study …

Background Despite high vaccine coverage, an increase in breakthrough coronavirus
disease 2019 (COVID-19) infections, prompted administration of a third BNT162b2 dose to …

The efficacy of COVID-19 vaccines appears to depend in complex ways on the vaccine
dosage and the interval between the prime and boost doses. Unexpectedly, lower dose …

The COVID-19 pandemic has severely impacted health systems and economies worldwide.
Significant global efforts are therefore ongoing to improve vaccine efficacies, optimize …

COVID-19 vaccines are the most critical measure for controlling the COVID-19 pandemic;
however, we have little information on their complications. We experienced a case of a …