the virus. >> only half my population is fully vaccinated here and that's posed a lot of risk. >> reporter: millions of kids headed back to class this week, many schools are already dealing with outbreaks. one fifth of all districts in kentucky temporarily closing because of infections. >> let's go have a talk. >> reporter: in arizona, debate over covid protocols are becoming heated. three men threatening the principal with citizens arrest. >> i will have both your staff arrested and you as well. >> reporter: after one of their sons was told to quarantine because of possible covid exposure. >> one of them, sorry, one of them was carrying zip ties. military black large zip ties and standing in my doorway. >> reporter: the father was later arrested fortress passing. >> this is protocol we were supposed to follow. >> reporter: as for the mu variant, dr. fauci is saying he does not believe at this point it to be an immediate threat to