NEW YORK -- The U.S. Centers for Disease Control and Prevention (CDC) said on Wednesday it is observing a lower rate of severe allergic reactions in people in the United States who have received Pfizer Inc and BioNTech SE's COVID-19 vaccine.

The CDC said that through Jan. 18, there were 50 cases of anaphylaxis reported in recipients of the vaccine. That implies a rate of about 5 per million doses administered, down from its previously reported rate of 11.1 per million doses administered through Dec. 23.

It reported 21 cases of anaphylaxis after Moderna Inc's COVID-19 vaccine was administered. That implies a rate of 2.8 cases per million doses, up slightly from the previously reported rate of 2.5 per million doses, based on data through Jan. 10.