Pfizer has submitted research to the US Food and Drug Administration on the effectiveness of its COVID-19 vaccine in children but the shots may not be available until November.
More than 200 million shots of COVID-19 vaccines have been administered in the United States as of Wednesday, according to the US Centres for Disease Control and Prevention (CDC).
The company at the centre of quality problems that led Johnson & Johnson to discard an unknown amount of its coronavirus vaccine has a string of citations from US health officials for quality control problems.