“This report provided the most compelling information to date that Covid vaccines were performing as expected in the real world,” Dr. Rochelle Walensky, the CDC director, said on Friday.
The findings are based on an ongoing study of health care workers in 25 states. This interim analysis included data on 1,843 health care. Over 80% of participants were female. Some 623 workers tested positive between January and mid-March. Those who were fully vaccinated were 94% less likely to develop symptomatic infections than their unvaccinated peers, the study found. The figures are consistent with the efficacy estimates from the clinical trials.
The scientists also found that a single dose of the two-shot regimen was 82% effective at preventing symptomatic infection. That figure is higher than has been reported in other studies and may be a result of the relative youth of the participants, who had a median age of 37 to 38. nyt