U.S. health officials on Saturday announced COVID-19 vaccines for infants, toddlers and preschoolers.

Although the Food and Drug Administration (FDA) has already given its approval to vaccines, it is the CDC that decides who should receive them.

Vaccines offer young children protection from hospitalization, death and possible long-term complications that are not yet clearly understood, according to the CDC advisory panel.

The government has been preparing for the start of vaccine expansion, with millions of doses ordered for distribution to doctors, hospitals and health clinics across the country.

Approximately 18 million children are eligible to receive the doses, but it remains to be seen how many are actually inoculated.

Less than a third of children aged five to 11 have received the injection since vaccination began for them in November last year.

The injections will be available next week, expanding the vaccination campaign for children from six months of age.

Advisors from the Centers for Disease Control and Prevention (CDC) recommended COVID-19 vaccines for younger children and final authorization was given hours later by CDC Director Dr. Walensky.

Rochelle Walensky is an American physician-scientist who is the director of the Centers for Disease Control and Prevention and the administrator of the Agency for Toxic Substances and Disease Registry.

“We know that millions of parents and caregivers are eager to vaccinate their young children and, with today’s decision, they can do so,” Walensky said in a statement.