Germ Mania is a 1927 Felix the Cat short produced by Pat Sullivan.
Plot[]
Felix sees a collection of empty bottles outside a laboratory and thinks that there must be a large quantity of milk inside. So he enters in search of a hearty meal. Hunting around inside, Felix discovers the marvels of microscopy, but in doing so, he annoys two kissing bugs and makes the male bug yearn for size so that he can thrash the intruder.
A chemist, who has perfected enlarging and reducing fluids, tries them out with great success on Felix. He bottles the tiny cat as a specimen, but Felix uses his brains, a magnet and corkscrew and gains his freedom.
But the osculation germ or kiss bug has been placed in an enlarging bath. He spots the diminutive Felix, and the chase is on. Felix saves himself by getting hold of the fluids which have caused so much havoc. He throws them in the path of the pursuing germ, finally reducing the kissing bug to its former microscopic condition. The chase ends when Felix, back to normal size, bottles his germ enemy.