The US Food and Drug Administration gave emergency approval Friday for the use of Pfizer and Moderna Covid-19 vaccines in the youngest children, the age group most nations have yet to immunize.

The FDA, whose clearance is regarded as the worldwide gold standard, approved Moderna's two-dose vaccination for children aged six months to five years, and Pfizer's injections for children aged six months to four years.

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FDA chief Robert Califf stated that "many parents, caregivers, and clinicians have been waiting for a vaccine for younger children and this action will help protect those down to six months of age," adding that "we expect that the vaccines for younger children will provide protection from the most severe outcomes of Covid-19, such as hospitalization and death."

Pfizer aims to submit license petitions to various regulatory bodies across the world, including the European Medicines Agency, in early July.

Ugur Sahin, CEO and co-founder of Germany's BioNTech who developed the vaccine along with Pfizer, stated that "parents in the US now have the option to vaccinate their children under 5 years of age, and we are working to ensure that other countries worldwide will follow."

The Centers for Disease Control and Prevention (CDC) must now endorse the vaccinations before they may be used in the United States, a final green light that will be granted following a meeting of an expert advisory group, which is scheduled to take place soon.

However, the government has stated that as soon as the FDA ruling is finalized, 10 million pills would be distributed around the country, followed by millions more in the coming weeks.

Both vaccines use messenger RNA to transfer the genetic information for the coronavirus spike protein to human cells, which then develop it on their surface, priming the immune system. The technique is now regarded as the most advanced Covid vaccination platform.

The immunizations were tested on thousands of youngsters in clinical studies. They were discovered to induce equal degrees of moderate side effects as older age groups and to elicit comparable amounts of antibodies.

Pfizer's efficacy against infection was greater, at 80%, compared to Moderna's estimations of 51% for children aged six months to two years and 37% for those aged two to five years.

However, the Pfizer figure is based on a small number of patients and is hence considered preliminary. It likewise requires three doses to provide protection, with the third shot administered eight weeks after the second, which is administered three weeks after the first.

After two doses, four weeks apart, Moderna's vaccine should provide good protection against severe disease, and the business is looking at adding a booster that would increase efficacy levels against mild sickness.

However, as compared to Pfizer, Moderna's decision to use a greater dosage is related to higher levels of fever in response to the vaccination.

Moderna CEO Stephane Bancel stated that "we are thrilled that the FDA has granted Emergency Use Authorization of Moderna's Covid-19 vaccine for children and adolescents, particularly for our vulnerable, youngest children."

Bancel added that "children need to live highly social lives to develop and flourish and that this authorization will give them a way to safeguard against Covid risks in educational settings such as daycares and classrooms."

According to the FDA, the United States, which has 20 million children aged four and under, has documented 480 Covid fatalities in that age range during the pandemic, significantly more than even a terrible flu season.