In this Sept. 1, 2011 file photo, Dr. Nancy Snyderman talks about child vaccination on the "Today" show in New York. NBC News medical reporter Snyderman spoke with Matt Lauer on the “Today” show, Wednesday, Dec. 3, 2014, and apologized for violating her quarantine for Ebola exposure, saying she failed to appreciate how frightened Americans were of the disease. (AP Photo/NBC, Peter Kramer, File)

NBC’s Snyderman returns with apology

NBC News medical reporter Nancy Snyderman is apologizing for violating her quarantine for Ebola exposure, saying she failed to appreciate ho…