Mega Disasters - S02E07: Alien Infection

Could an alien infection cause an epidemic on earth? Some experts believe that spacecraft returning from Mars could bring back a harmful sample or comet dust falling into our atmosphere could cause pandemics. One astronomer believes that the 1918 flu pandemic, which killed between 50-100 million people, was one such outbreak and that another "infection" could decimate the world's population. Astrobiologists are now poised to bring Mars samples back to earth to examine them in a Bio 4 level safety lab. In a hypothetical future disaster scenario, track how comet dust would seed the earth with a virulent virus. Quarantine measures don't work and panic ensues.