Three new studies by the US Centers for Disease Control and Prevention (CDC) reveal that Pfizer-BioNTech and Moderna booster shots were 90% effective at keeping people out of hospital after they had contracted the Omicron variant of the COVID-19 virus.
Booster jabs were also 82% effective at preventing emergency department and urgent care visits, research data indicated.
The research comprised the first large US studies to look at vaccine protection against Omicron, health officials said.
“Americans should get boosters if at least five months have passed since they completed their Pfizer or Moderna series, but millions who are eligible have not gotten them,” the CDC’s Emma Accorsi, one of the study’s authors said.
The papers echo previous research – including studies in Germany, South Africa and the United Kingdom – indicating available vaccines are less effective against Omicron than earlier versions of the coronavirus, but also that booster doses rev up virus-fighting antibodies to increase the chance of avoiding symptomatic infection.