New Studies: COVID vaccines effective, with limited waning

Studies: COVID vaccines effective, with limited waning In 1 of the 3 studies, vaccination was 98% protective against ICU stay and life support in teens. CIDRAP

A trio of new studies yesterday in the New England Journal of Medicine report encouraging results on the effectiveness and durability of protection of COVID-19 vaccines against hospitalization and death, including teens.

98% protection against ICU stay, life support

One study, led by the Centers for Disease Control and Prevention's (CDC's) COVID-19 Response Team, involved 445 hospitalized COVID-19 patients 12 to 18 years old and 777 uninfected matched controls at 31 hospitals in 23 states from Jul 1 to Oct 25, 2021, after the emergence of the Delta (B1617.2) variant. Seventeen case patients (4%) and 282 controls (36%) had received two doses of the Pfizer/BioNTech COVID-19 vaccine. ...

Of the current study, the authors said, "In this real-world evaluation of the effectiveness of the BNT162b2 mRNA vaccine in adolescents between 12 and 18 years of age in the United States, when the delta variant was predominant, we found that the vaccine was highly effective against Covid-19 hospitalization and critical illness, including among patients with underlying risk factors for severe illness. Vaccination averted nearly all life-threatening Covid-19 illness in this age group."

In a related editorial, Kathryn Edwards, MD, of Vanderbilt University Medical Center, noted that as of Dec 1, only 15% of US children aged 5 to 11 years had received at least one COVID-19 vaccine dose, a figure that contrasts sharply to the 95% vaccine uptake of routine pediatric vaccines. By Dec 23, more than 7.5 million US children had been infected, and 721 had died, she added. ...

VE against hospitalization fell to 80%, 92% at 5 months

A study led by United Kingdom Health Security Agency researchers assessed the effectiveness of the Pfizer and AstraZeneca vaccines among COVID-19 patients in England from Dec 8, 2020, to Oct 1, 2021, a period marked by the emergence of Delta. ...

"Our data provide evidence of waning of protection against symptomatic infection after the receipt of two doses of the [AstraZeneca] or [Pfizer] vaccine from 10 weeks after receipt of the second dose," the study authors wrote. "Protection against hospitalization and death, however, was sustained at high levels for at least 20 weeks after receipt of the second dose."

Pfizer, Moderna fared better than J&J

An observational study led by University of North Carolina at Chapel Hill (NCCH) researchers involved mining data on COVID-related outcomes and vaccination with the Pfizer, Moderna, and Johnson & Johnson (J&J) vaccines from Dec 11, 2020, to Sep 8, 2021, for about 10.6 million state residents. ...