Nobody remembers this one because it's an educational short about disease transmission, but that's exactly why it matters. Japan's animators took what microscope footage could show and made it move in ways live-action never could, turning invisible threat into something you could actually see spreading through a room. A hygiene PSA from 1925 that still teaches you something about how contagion works, rendered with the clarity that only animation allows.

Diseases Spread is a short educational film made to raise public awareness of hygiene, told entirely through animation with no live-action footage. It shows how everyday habits, such as eating undercooked fish, leaving scraps out until flies gather on them, and doing laundry in the river, let serious illness spread before anyone notices. As safeguards, it urges disinfecting with a solution made from bleaching powder, putting on a mask to keep germs out of the body, and airing bedding in the sun. The film warns that one person's carelessness can reach a whole household and eventually carry disease across Japan. It builds on the Ministry of Education's earlier science films, which relied on microscopic cinematography.