The effectiveness of two doses of the Pfizer/BioNTech COVID-19 vaccine in opposition to hospitalization for infections with the extremely transmissible Omicron variant was 40% amongst adolescents 12 to 18 years and 68% amongst youngsters aged 5 to 11, finds a test-negative study printed yesterday within the New England Journal of Medication (NEJM).
Led by the Facilities for Illness Management and Prevention’s (CDC’s) COVID-19 Response Crew, the research concerned 1,185 COVID-19 sufferers admitted to 31 US pediatric hospitals and 1,627 controls aged 5 to 18 years admitted for different indications. The 918 adolescents have been enrolled from Jul 1 to Dec 18, 2021 (Delta variant period) and from Dec 19, 2021, to Feb 17, 2022 (Omicron period).
The 267 youngsters aged 5 to 11 have been enrolled solely through the Omicron interval as a result of the Pfizer vaccine wasn’t approved for that age-group till October 2021. Owing to inadequate numbers of severely in poor health sufferers on this age-group, VE in opposition to important sickness—outlined as those that required life help, similar to mechanical air flow—could not be evaluated.
92% efficient in teenagers for as much as 10 months
Among the many 1,185 whole hospitalized sufferers, 1,043 (88%) have been unvaccinated, 291 (25%) required life help, and 14 (1.2%) died.
Of 12- to 18-year-olds, 87% have been unvaccinated, 27% have been critically in poor health, of whom 2% wanted extracorporeal membrane oxygenation (ECMO) (93% of them have been unvaccinated), and 13 died. Amongst youngsters 5 to 11 years, 92% have been unvaccinated and 16% wanted life help (90% unvaccinated), together with 2 who required ECMO and 1 who died.
Vaccine effectiveness (VE) of two doses of the Pfizer vaccine given a minimum of 14 days earlier in opposition to COVID-19 hospitalization amongst 12- to 18-year-olds within the Delta-dominant interval was 93% (95% confidence interval [CI], 89% to 95%) 2 to 22 weeks after vaccination and 92% (95% CI, 80% to 97%) at 23 to 44 weeks.
Within the Omicron-dominant interval, VE was 40% (95% CI, 9% to 60%) in opposition to hospitalization, 79% (95% CI, 51% to 91%) in opposition to important COVID-19, and 20% (95% CI, −25% to 49%) in opposition to noncritical sickness amongst 12- to 18-year-olds after a median interval of 162 days since vaccination. Amongst sufferers aged 5 to 11, VE in opposition to Omicron hospitalization was 68% (95% CI, 42% to 82%) at a median of 34 days after vaccination.
“Continued monitoring of vaccine effectiveness in opposition to extreme Covid-19 will probably be essential to tell vaccination methods because the time since vaccination will increase or if new SARS-CoV-2 variants emerge,” the research authors concluded.
Solely 57% of teenagers, 27% of children vaccinated
In a Boston Kids’s Hospital news release, senior writer Adrienne Randolph, MD, stated that COVID-19 vaccines are designed to avert extreme issues similar to hospitalization. “This proof exhibits that vaccination reduces this threat considerably in 5- to 11-year-olds,” she wrote. “And whereas vaccination offered adolescents with decrease safety in opposition to hospitalization with omicron versus delta, it prevented important sickness from each variants.”
As of Mar 16, 2022, the researchers stated, solely 57% of 12- to 18-year-olds and 27% of these aged 5 to 11 had acquired two Pfizer doses.
“We hope our findings will assist dad and mom make the choice to vaccinate their youngsters and teenagers in opposition to COVID-19,” Randolph stated. “The advantages clearly outweigh the dangers, as extreme infections in childhood can have long-term penalties.”
In a NEJM audio interview, Eric Rubin, MD, PhD, editor-in chief, and Deputy Editor Lindsey Baden, MD, stated the findings are in keeping with what has been seen in vaccinated adults. “Vaccines are greatest at defending in opposition to variants which might be most just like the vaccine strains just like the Delta variant and never nearly as good in opposition to less-similar strains like Omicron, and so they work greatest in opposition to extreme sickness” Rubin stated.
Baden identified that that COVID-19 vaccine unwanted effects are very uncommon.
“In my very own reflection on this, the danger of a one-in-a-million or very uncommon aspect impact—be it the myocarditis or the anaphylaxis or a few of these issues that are nonetheless laborious to grasp given their rarity—versus the clear advantages of defending in opposition to the sickness, makes it an easy choice,” he stated.