studies show a booster provide considerable protection. today, the white house made it clear: to fight omicron, americans need a booster shot. >> our booster vaccine regimens work against omicron. at this point, there is no need for a variant-specific booster. >> reporter: just 30% of fully vaccinated adults have a booster. >> it is a necessity. >> reporter: to emphasize the need for that extra shot, new jersey declared today "booster day," one year after the first vaccines were administered. omicron is surging there and in new york, making up 13% of cases, compared to 3% nationwide. the variant is now reported in 36 states, washington, d.c., and puerto rico. >> this is a roll of the dice. you don't know for sure that you're going to just slide right through it without any problem. we also know that prior infection with covid is not