Germs was a henchman who served Roland Daggett. He was extremely germaphobic, to the point that he used handkerchiefs to open doors rather than touch the knobs with his bare hands.
Later, Daggett ordered Germs and Bell to dispose of Matt Hagen, who had been doing some of Daggett's dirty work in exchange for Renuyu to restore his face. They caught Hagen breaking into Daggett Labs to take some Renuyu for himself. They decided to do away with him by pouring a whole vat of the chemical down his throat. Instead of killing him, however, it transformed him into the shapeshifting monster Clayface.
Germs next task was sent to kill Fox in the hospital. His attempt on Fox's life was thwarted by Batman, who cornered him in the hospital's viral pathology lab. Threatening him with a beaker of what he claimed was crimson fever, which was actually just mere saltwater, Batman learned that it was Hagen who had impersonated Bruce Wayne to fool Fox. Shortly afterwards, Clayface appeared and carried Germs to the roof, planning to throw him off to his death. Batman rescued him though, and after driving Clayface away left a traumatized Germs to be arrested by the police. Like with Bell, as there was no solid evidence against Germs for his crimes, it is unknown if he was ultimately imprisoned.