Vaccinations for infants, toddlers and preschoolers opened in the United States in June after months of delays. Only about 6% of young adults between the ages of 6 months and 4 years had received at least one dose of the COVID-19 vaccine by mid-August, according to the American Academy of Pediatrics.
Health authorities have authorized large-volume vaccine doses from Pfizer and its partner BioNTech based on a study that showed it was safe and produced high levels of virus-fighting antibodies. But there has been only preliminary data on how this translates into effectiveness against Symptoms of Covid-19 disease.
There were 21 cases of COVID-19 among the 351 children who got a dummy shot – compared to just 13 of the 794 young people given three doses of the vaccine.
The pediatric cases were mainly caused by the BA.2 Omicron version that was in circulation at the time. Today, another relative of Omicron, BA.5, causes the most cases of COVID-19 in the United States and most of the world.
In older children and adults, the COVID-19 Vaccines They’ve been used long enough to show that they remain a powerful preventative against severe disease and death even as the coronavirus mutates — while early protection against infection wanes. However, scientists are still tracking this initial efficacy rate as further evidence of the vaccine’s performance — and to look for signs of how they initially resisted the new mutations.
Pfizer this week Request for regulators in the United States To allow modified vaccine doses to better match Omicron’s newest variants for people 12 and older as boosters this fall. The company said it is also developing updated footage for children under 12 years old.
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