Day of Resurrection (1980) on Netflix

When a deadly virus is unleashed, it wipes out most of the world's population. But it's dormant in sub zero temperature so that means everyone at a polar station in Antartica are not infected so it's up to them to rebuild humanity. But then a seismologist determines that an earthquake will hit Washington that's when some people from the military from America, England and Russia reveal that the earthquake will activate a retaliatory system which will launch an attack on Russia which will then activate a Russian system that will launch an attack on the station. So two men are sent to Washington to try and stop it.