Measles cases in West Texas are still rising two months after the outbreak began.

The U.S. has improved its surveillance system for tracking new coronavirus variants such as omicron, boosting its capacity by tens of thousands of samples since early this year.

The United States opened its borders to people fully vaccinated against COVID-19, but some who got the shots are finding they're still not eligible to visit.

Coronavirus infections among the New York Yankees team and staff underscore that the infections are possible even after vaccination.

Pfizer has said it will have about 25 million doses of the two-shot vaccine for the U.S. by the end of December. Next week, the FDA will review a second vaccine, from Moderna and the National Institutes of Health, that appears about as protective as Pfizer-BioNTech’s shot. As a result, the expert panel wrestled with a list of questions that have yet to be answered. The company proposed gradually moving those patients to the vaccine group, with priority based on age, health conditions and other factors. Pfizer must still show whether the vaccine works in children younger than 16 and in pregnant women.