The omicron variant has been identified in at least 21 states, but the World Health Organization is pointing to early…
The Centers for Disease Control and Prevention signed off on a recommendation for Pfizer boosters for 16- and 17-year-olds in…
New questions are being raised as to whether COVID-19 vaccines can keep up with newly emerging variants. ABC News Live…
ABC News Bob Woodruff looks at how effective existing vaccines are against variant strains of the coronavirus and how long…