Flu (2013) on Netflix

Plot summary

An unknown illness kills illegal immigrants hidden in a shipping container in Seoul. Smugglers Ju Byung-woo and Ju Byung-ki carry the sole survivor, Monssai, and a video to Bundang, where Byung-woo falls sick and Monssai escapes. The contagion spreads through a clinic and into the city. Dr. Kim In-hae, who works at Bundang's Contagion Center, studies the video and suspects the virus mutated in the container. Byung-woo is isolated with an unknown flu. Rescue worker Oh Ji-goo helps In-hae's daughter, Mi-reu. The illness is a mutated H5N1 that kills in as little as 36 hours, and officials order the city of nearly half a million sealed off. In-hae and Ji-goo go into the closed zone to find the index case's blood serum, a key part of developing a vaccine.