Pfizer and BioNTech have announced the results of the Covid vaccine in children under the age of 12. In the United States, one out of five new cases involves a minor and the Delta variant has raised the number of pediatric hospitalizations (including intensive care) to a level never seen before
The Pfizer and BioNTech’s Covid vaccine
And Safe and highly effective even in children aged 5 to 11 years.
This was announced by the two manufacturers without however providing details on the results of clinical phase 2/3, which for the moment have not even been published in preprint. The effectiveness in under 12, according to the producers, it is comparable with that obtained in the older age groups.
The news was long awaited: out of five new cases in the United States, one concerns a minor and the Delta variant has brought the number of pediatric hospitalizations (including in intensive care) to a level never seen during the pandemic, especially following the reopening of schools. “Since July, pediatric cases of Covid have increased by about 240% in the US,” said Albert Bourla, president and CEO of Pfizer.
The two companies plan to present application for authorization from the Food and Drug Administration (Fda) and the European Medicines Agency (Ema) by the end of September.
Full approval of the Pfizer vaccine by the FDA in August was about gli over 16. Children aged 12 to 15 can still receive it thanks to the emergency authorization. The vaccine of Modern it can be used today from 12 years upwards. Soon, most likely, it will be possible to protect even the little ones.
Not only. Pfizer and BioNTech have initiated studies on children aged between 6 months and 2 years and between 2 and 5 years. The results are expected, the two companies explained, “before the end of the year”. And there are those who carry on: Israel has given special permission to vaccinate 5-11 year olds who are “at significant risk of serious illness or death” for Covid, using Pfizer at the lowest dosage.
Multisystem inflammatory syndrome
As we know, children have a low risk of becoming seriously ill with Covid, but a small percentage develop the potentially dangerous multisystem inflammatory syndrome (MIS-C).
Others suffer from long Covid and have persistent symptoms for months.
Furthermore, even if they often become infected asymptomatically, they can infect teachers, parents, grandparents and especially immunosuppressed people who (despite the vaccine) risk death from Sars-CoV-2.
Immune response measured
Pfizer’s experimentation included 2,268 children aged 5 to 11: two thirds received the double dose of the vaccine three weeks apart; the others were injected with two doses of placebo.
The study was not large enough to draw conclusions about the vaccine’s ability to prevent disease or hospitalization (given the low frequency of such events in children), so the researchers measured the immune response, assuming that the protective levels of antibodies observed in adults are equally effective in children.
Few side effects with one third of the dose
I results, presented by the two companies, are extremely promising.
Children who received the vaccine produced a strong immune response, comparable to the antibody levels seen in a control group of people aged 16 to 25.
The only difference is in the dose: in children between 5 and 11 years of age, 10 micrograms were sufficient, one third of the amount currently offered to over 12s and adults. At higher doses, the researchers observed a greater frequency of side effects (albeit mild): fever, headache and fatigue. “Immune defenses weaken with age and side effects also become milder. This is why most vaccines are given in infancy and explains why a much lower dose is enough in children, ” said Yvonne Maldonado, who led the trial at Stanford University and chairs the Infectious Diseases Committee. ‘American Academy of Pediatrics -. A compromise dose has been selected which minimizes the reactions, but allows to obtain a good antibody response ». In children under 5, from the first studies, it seems that 3 micrograms, one-tenth of the standard dose, are enough.
The (low) risk of myocarditis and pericarditis
The FDA is also evaluating the (very rare) risk of post vaccine side effects in children and young people, in particular the attention has focused on cases of myocarditis and pericarditis.
But a large Israeli study, based on the medical records of two million over 16s, showed that the odds of developing this heart inflammation are much higher in children who contract Covid than in those who are vaccinated.
For safety, in July the FDA asked Pfizer / BioNtech and Moderna to extend the tests to another 3 thousand children and the results are awaited. “Some people are convinced that children should not be vaccinated – concluded Maldonado -. Although most of the children do not get serious illness, pediatric hospitals and intensive care units are overflowing in the United States. Why not prevent an infection that can lead the child to be hospitalized in a serious condition? ».
September 20, 2021 (change September 20, 2021 | 20:48)