The virus’ resurgence is being driven by yet another version of Omicron. Genomic surveillance for the two weeks ending July 27 finds variant NB 1.8.1 responsible for 43 percent of sequenced US cases, ...

Booster shots appear to be at least 90% effective against hospitalization for both Delta and Omicron, new CDC data show.

US hospitals strained with influx of patients amid latest COVID surge, staffing shortages Omicron and delta are putting additional pressure on an overtaxed health system.

The Biden administration's new efforts come as the omicron variant became the most dominant COVID-19 strain in the country Monday.

We also estimated the risk and burden of PASC in combinations of cohorts, including the pre-delta era cohort and the unvaccinated delta era cohort, both delta era cohorts, both omicron era cohorts ...

Findings indicate a sharp drop in immunity after Omicron infection, stressing the necessity for updated vaccines to enhance protection against reinfection.