COVID-19 vaccine effectiveness for all age groups has been much worse against the Omicron virus variants than earlier strains, particularly the currently dominant subvariants, according to U.S. Centers for Disease Control and Prevention (CDC) data presented on Sept. 1.
The data, much of which has never been published before, shows that the protection against both symptomatic infection and severe disease is not as strong against the Omicron, which emerged in December 2021, and its subvariants.
Data from the CDC’s Increasing Community Access to Testing, a no-cost testing program, showed that vaccine effectiveness for a booster compared to a primary series against symptomatic infection waned rapidly across all age groups, going under 50 percent within two months and turning negative around six months….