Until now, the Pfizer vaccine was authorized from the age of 5 and that of Moderna from the age of 18.

Both are now cleared by the US Drug Administration (FDA) for babies, children and adolescents from 6 months of age, she announced.

The very young are the last age group not yet to have received this protection in the United States, as in many countries.

“Many parents, caregivers and clinicians have been waiting for a vaccine for the youngest children, and this action will protect those from 6 months of age,” said Robert Califf, the head of the FDA, in a press release.

“As we have seen in older age groups, these vaccines for younger children are going to provide protection against the most severe cases of Covid-19, such as hospitalizations and deaths.”

The Centers for Disease Control and Prevention (CDC) must now also recommend these vaccines for injections to begin, possibly as early as next Tuesday.

This final green light should, unless there is a big surprise, be granted after a meeting of expert members of an advisory committee, which was held over two days this Friday and Saturday.

But the US government had indicated that, as soon as the FDA decision was made, some 10 million doses could immediately begin to be sent in advance to the four corners of the country, before millions more in the following weeks.

The equipment needed for injections, such as small needles, will also be provided.

These two vaccines, which use messenger RNA technology, are safe and effective, said this week experts who are members of an advisory committee who have carefully reviewed the data from clinical trials.

FDA decisions are often referenced around the world.

Pfizer said in a statement that it intends to file applications for authorization for this youngest age group with other regulatory agencies, including the European Medicines Agency (EMA) "in early July".

Pfizer in three doses

The Moderna vaccine, in two doses administered one month apart, is now authorized as an emergency for children between six months and 5 years old, at a reduced dosage of 25 micrograms.

For children between 6 and 11 years old, the dosage is 50 micrograms, and for those between 12 and 17 years old, it is the same as for adults, 100 micrograms.

The Pfizer-BioNTech vaccine is authorized between six months and 4 years at a rate of 3 micrograms, or one tenth of the dosage used for adults.

Main difference: to elicit a sufficient immune response, it will have to be done immediately in three doses – the first two at three week intervals, the third administered eight weeks after the second.

Experts have pointed out that children receiving it would therefore not be properly protected for several months.

This very low dosage was favored by Pfizer in order to limit side effects as much as possible.

During clinical trials, the fever rates observed were thus comparable between children who received the vaccine and those who received the placebo.

At Moderna, about a quarter of young children who received the vaccine developed a fever, especially after the second dose.

But it usually subsided after a day.

The United States has approximately 20 million children aged four and under.

Even if the youngest are less vulnerable to Covid-19, some 480 children in this age group have nevertheless died in the United States.

Hospitalization rates also increased sharply for toddlers during the wave linked to the Omicron variant.

In total, there have been 45,000 children under the age of five hospitalized in the United States since the start of the pandemic, of which a quarter had to be admitted to intensive care.

Like adults, children infected with Covid-19 may also suffer from long-term symptoms (long Covid).

In rare cases, they may also develop severe cases of pediatric multisystem inflammatory syndrome.

© 2022 AFP