Why changing the definition of 'fully vaccinated' could be difficult

Article reports that the US Centers for Disease Control and Prevention might consider redefining what it means to be 'fully vaccinated' against Covid-19 to include a third dose of vaccine -- but the question is when the definition could change. Such a change is 'on the table and open for discussion,' Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Friday. 'That's certainly on the table. Right now, it is a bit of semantics,' Fauci told CNBC's Andrew Ross Sorkin on 'Squawk Box.' Fauci was referring to the definition of 'fully vaccinated' for the purpose of regulations or businesses that may require vaccination.