I'm a microbiologist who wanted to show the importance of covering your mouth properly - using a tissue to cover your mouth and nose, or into your elbow, turned away from others. In this clip I sneezed onto an agar plate, which is a jello-like substance used in microbiology labs to grow bacteria. And within 24 hours you can see the thousands of bacterial colonies growing on the plate. This is what people spread when they sneeze!