Mass murders, vandalism, social media abuse, propaganda, assault – by virtually every yardstick, antisemitism in the U.S. and Europe is rising and worsening in ways not seen since the 1930s. Like a virus, it mutates and evolves across cultures, borders and ideologies, making it all but impossible to stop. Filmmaker Andrew Goldberg explores its infectious behavior in his film “Viral: Antisemitism In Four Mutations.”