Three studies released Friday offered more evidence that COVID-19 vaccines are standing up to the omicron variant, at least among people who received booster shots.
It found vaccine effectiveness was best after three doses of the Pfizer or Moderna vaccines in preventing COVID-19-associated emergency department and urgent care visits. Protection dropped from 94% during the delta wave to 82% during the omicron wave. Protection from just two doses was lower, especially if six months had passed since the second dose.
The second study focused on COVID-19 case and death rates in 25 states from the beginning of April through Christmas. People who were boosted had the highest protection against coronavirus infection, both during the time delta was dominant and also when omicron was taking over.The Journal of the American Medical Association published the third study, also led by CDC researchers. It looked at people who tested positive for COVID-19 from Dec. 10 to Jan.
Three shots of the Pfizer and Moderna vaccines were about 67% effective against omicron-related symptomatic disease compared with unvaccinated people. Two doses, however, offered no significant protection against omicron, the researchers found. “It really shows the importance of getting a booster dose,” said the CDC’s Emma Accorsi, one of the study’s authors.The Associated Press Health & Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.