John W. Karapelou created this image to show two potential agents in upper respiratory infections, bordetella pertussis bacteria, and H1N1 influenza virus.

Bordetella pertussis bacteria is commonly known as the cause of whooping cough, a very contagious disease.

H1N1 influenza virus is a variation of the seasonal flu that is referred to as swine flu. It can lead to more serious problems such as pneumonia, lung infection, and other respiratory problems.

To see more work from John, visit his Medical Illustration & Animation portfolio and his site: