Watch Mary Shelley's The Last Man

This is a movie based on the book by the same name. A bioweapons lab in Siberia is looted by people on the black market. There is a strain of small pox in the lab that creates a pandemic. There is only 2% of the population left in the world. People are running out of food and other supplies. As the food is depleted, they turn into cannibals until there is only one man left.