Vaccinations against the novel coronavirus for children aged 5 to 11 are under way, U.S. media reported Wednesday, following approval by U.S. health authorities the previous day for use of the Pfizer Inc. vaccine for the age bracket.

The recommendation by the Centers for Disease Control and Prevention on Tuesday paved the way for COVID-19 vaccinations for some 28 million children.

Photo shows vials of Pfizer Inc.'s COVID-19 vaccine at a hospital in Iwamizawa, Hokkaido, northern Japan, on Feb. 19, 2021. (Kyodo) ==Kyodo

Eligible children are mostly expected to receive shots at clinics, pharmacies and schools, rather than large inoculation sites. They will get one-third of the dosage of Pfizer vaccine used for people aged 12 or older.

The U.S. pharmaceutical company said the smaller dosage can create antibodies and provide vaccine efficacy for children at the same level received by older individuals who receive a full dose.

Although the number of new daily coronavirus infection cases has been decreasing since late September in the United States, the administration of President Joe Biden hopes to contain the spread in winter as many schools return to in-person classrooms.

According to CDC data, a total of over 1.9 million children aged 5 to 11 had been infected with COVID-19 in the United States as of late October, while the country has seen more than 46 million infections, the highest in the world.