Immunizations for babies, toddlers and preschoolers opened in the US in June after months of delays. According to the American Academy of Pediatrics, only about 6% of teenagers ages 6 months to 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 full-sized doses of vaccines produced by Pfizer and partner BioNTech based on a study that found them to be safe and produce high levels of antibodies against the virus. But there is only preliminary data on how that translates to effectiveness against COVID-19 has symptoms.
There were 21 cases of COVID-19 among the 351 children who received the dummy shots — compared with just 13 cases out of 794 children who received three doses of the vaccine.
The pediatric cases were mainly due to the BA.2 version of Omicron circulating at the time. Today, another relative of Omicron, BA.5, is causing most of the COVID-19 cases in the United States and much of the world.
In older children and adults, Vaccines against covid-19 have been used long enough to demonstrate that they still offer strong protection against serious illness and death even when the coronavirus mutates — while the early protection against infection fades. However, scientists still monitor that initial effectiveness rate as additional evidence of vaccines’ effectiveness — and to look for signs of how they fight off new mutations initially. .
Pfizer this week ask US regulators to allow doses of the modified vaccine to be more suitable with the latest Omicron variants for people 12 years of age and older as boosters this fall. The company says it is also developing updated shots for children under 12.
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