Someone in a research lab on the floor below screwed up. Some smallpox virus managed to float up through the vents into the room where she was working.
يکي از همکاراش تو آزمايشگاه، گند ميزنه و يه مقدار ويروس آبله رو مي‌ريزه زمين که از اونجا وارد هواکش ميشه و ميره تو اتاقي که اون کار مي‌کرده