PS
The study
Effectiveness of the BNT162b2 vaccine among children 5-11 and 12-17 years in New York after the
Emergence of the Omicron Variant
https://www.medrxiv.org/content/10.1101/2022.02.25.22271454v1.full.pdf
Results:
From December 13, 2021 to January 30, 2022, among 852,384 fully-vaccinated children 12-17
years and 365,502 children 5-11 years, VE against cases declined from 66% (95% CI: 64%, 67%) to 51%(95% CI: 48%, 54%) for those 12-17 years
and from 68% (95% CI: 63%, 72%) to 12% (95% CI: 6%, 16%) for those 5-11 years. During the January 24-30 week, VE for children 11 years was 11% (95%CI -3%, 23%)
and for those age 12 was 67% (95% CI: 62%, 71%).
VE against hospitalization declined changed from 85% (95% CI: 63%, 95%) to 73% (95% CI: 53%, 87%) for children 12-17 years, and from 100% (95% CI: -189%, 100%) to 48% (95% CI: -12%, 75%) for those 5-11 years.
Among children newly fully-vaccinated
December 13, 2021 to January 2, 2022, VE against cases within two weeks of full vaccination for children 12-17 years was 76% (95% CI: 71%, 81%)
and by 28-34 days it was 56% (95% CI: 43%, 63%).
For children 5-11, VE against cases declined from 65% (95% CI: 62%, 68%) to 12% (95% CI: 8%, 16%) by 28-34 days.
Conclusions and Relevance:
In the Omicron era, the effectiveness against cases of BNT162b2 declined rapidly for children, particularly those 5-11 years. However, vaccination of children 5-11 years was protective against severe disease and is recommended. These results highlight the potential need to study alternative vaccine dosing for children and the continued importance layered protections, including mask wearing, to prevent infection and transmission.