In this photo taken Wednesday, Jan. 6, 2021, an empty tent set up in front of Institute of Virology, Vaccines and Sera "Torlak" in Belgrade, Serbia. Across the Balkans and the rest of the nations in the southeastern corner of Europe, a vaccination campaign against the coronavirus is overshadowed by heated political debates or conspiracy theories that threaten to thwart the process. In countries like the Czech Republic, Serbia, Bosnia, Romania and Bulgaria, skeptics have ranged from former presid