COVID-19 and influenza are similar and different in various ways, and differentating between the two is critical as the pandemic's second year is underway. Patient Care Online previously published a quiz on this topic based on the US Centers for Disease Control and Prevention's (CDC) page comparing COVID-19 and flu. With new research on COVID-19 being published almost daily, the CDC recently updated its page to include the latest information on transmission, complications, vaccines, and more. Take the 7-question quiz below to see what you've learned since last year.