Lauran Neergaard

Immunocompromised Americans at high risk from COVID-19 are now allowed to get a third vaccination in hopes of better protection.

Health authorities are trying to determine whether heart inflammation that can occur along with many types of infections could also be a rare side effect in teens and young adults after the second dose of COVID-19 vaccine.

Moderna aims to be next in line to offer vaccine to younger teens, saying it will submit its data to the FDA and other global regulators early next month.

Shots could begin as soon as a federal vaccine advisory committee issues recommendations for using the two-dose vaccine in 12- to 15-year-olds, expected Wednesday.

A U.S. health panel says it’s time to resume use of Johnson & Johnson’s COVID-19 vaccine, despite a very rare risk of blood clots.

At an emergency meeting, CDC advisers wrestled with the fact that the U.S. has enough alternative shots to vaccinate its population — but other countries awaiting the one-and-done vaccine may not.

The Centers for Disease Control and Prevention and the Food and Drug Administration said they were investigating unusual clots in six women that occurred six to 13 days after vaccination.

Vaccinating children of all ages will be critical to stopping the pandemic — and helping schools start to look a little more normal after months of disruption.

AstraZeneca said it had analyzed more data from that study and concluded the vaccine is 76% effective in preventing symptomatic COVID-19, instead of the 79% it had reported earlier in the week.

AstraZeneca said its experts did not identify any safety concerns related to the vaccine, including finding no increased risk of rare blood clots identified in Europe.

One challenge in rolling out the new vaccine will be explaining how protective the single shot is after the astounding success of the first double-shot vaccines.

The Food and Drug Administration’s scientists confirmed that the vaccine is about 85% effective at preventing severe COVID-19, and it is safe.

Johnson & Johnson asked U.S. regulators to clear the world’s first single-dose COVID-19 vaccine, an easier-to-use option that could boost scarce supplies.

While multiple vaccines have shown they prevent people from getting very sick, less is known about their ability to prevent people from spreading the virus to others.

The single-shot vaccine was 66% effective overall at preventing moderate to severe illness, and much more protective — 85% — against the most serious symptoms.