Five months after immunization, two doses of the Pfizer-BioNTech vaccine appeared to offer virtually no defense against moderate illness caused by the omicron variant — as measured by visits to emergency departments and urgent care clinics — among adolescents aged 12 to 17 years, according to data published on Tuesday by the Centers for Disease Control and Prevention.
But booster shots dramatically increased the protection, lending support to the agency’s recommendation of booster shots for everyone 12 and older.
The findings must be interpreted with caution. The agency’s study did not exclude unvaccinated adolescents who had some immunity from a prior infection, which may have made vaccination seem less effective than it was.