More children suffered a severe reaction to vaccine than required oxygen therapy

https://www.nejm.org/doi/full/10.1056...

BNT162b2 messenger RNA (mRNA) vaccine (Pfizer–BioNTech)

20th July 2022

Data on the real-world effectiveness of vaccines against omicron in children

METHODS

January 21, 2022, through April 8, 2022

Singapore, 5 to 11 years

N= 255,936 children

Fully vaccinated, 67.7% (173, 268)

Partially vaccinated, 12% (30,712)

Unvaccinated, 20.3% (51,995)

16.4 to 17.9 million person-days at risk

53,429 infections

5,342 PCR-confirmed

288 hospitalizations

Among hospitalized children

Five received supplemental oxygen

four of whom, admitted ITU

Of these five children

One was unvaccinated

Two were partially vaccinated

Two were fully vaccinated

No deaths attributable to Covid-19

Among the children in the unvaccinated group

(per 1 million person-days)

All reported infections, 3,303
PCR-confirmed infections, 479
Hospitalizations, 30

Among the children in the fully vaccinated group

All reported infections, 2,770
PCR-confirmed infections, 112
Hospitalizations, 6.6

Vaccine efficacy against hospitalization

Partially vaccinated v unvaccinated children

All reported infections, 13.6%

PCR-confirmed infections, 24.3%

Hospitalizations, 42.3%

In fully vaccinated children

All reported infections, 36.8%

PCR-confirmed infections, 65.3%

Hospitalizations, 82.7%

Vaccine effectiveness against all confirmed infections

Fully vaccinated v unvaccinated group

At times after 2nd dose of vaccine

7 to 14 days, 48.9 %

15 to 29 days, 37.6%

30 to 59 days, 28.5%

60 days or more, 25.6%

CONCLUSIONS

During a period when the omicron variant was predominant,

BNT162b2 vaccination reduced the risks of SARS-CoV-2 infection and Covid-19–related hospitalization among children 5 to 11 years of age.

these findings suggest greater vaccine effectiveness against higher levels of disease severity,

The results of this study may provide insights to enable decision makers to weigh the benefits against the potential risks of vaccination of children.

In Singapore, 22 serious adverse events after vaccination

(0.005% of all doses administered)

0.05 in 1,000

0.5 in 10,000

5 in 100,000

among children 5 to 11