cancellations that were announced after several of the cast and crew experienced those breakthrough cases. and then, of course, the radio city christmas spectacular that is extremely popular, they canceled their performances for the rest of the season. when you hear from many new yorkers, there's certainly a feeling of deja vu with these kind of closures and cancellations, although this time many people counting on the additional protection of their vaccines. polo vasandoval, cnn, new york. we'll take you now to the university of nebraska medical center. this hospital has been on the front lines of the coronavirus pandemic from the very beginning. it's where u.s. federal officials sent 13 infected passengers aboard the "diamond princess" cruise ship. clinicians there were among the first in the nation to develop their open in-house coronavirus test. joining me now is neinfectious disease specialist, dr. lawler.