Health Canada's chief medical advisor Dr. Supriya Sharma announced Thursday that Moderna's COVID-19 vaccine has been authorized for use for those from six months to five years old, adding it is a smaller dosage than what is being given to those above five or 12 and older. Canada's deputy chief medical officer of health Dr. Howard Njoo said that a two-dose primary series can be given eight weeks between shots, with immunocompromised children recommended to get a three-dose series with four-to-eight week wait between shots.