Remember, don't let them out!
Germs was a toyline released in 1988 by Worlds of Wonder as a continuation of the "gross" toy fad that seemed ubiquitous during the latter half of that decade. The Germs themselves represented common ailments trapped in a test tube along with a Lab Report (the Lab Reports of Oochi and Muggy are shown below). OCD kids everywhere revelled at the hideous visage of the object of their germophobic obsessions, while kid sisters screamed in horror (at least, according to the packaging).
The line started with test tubes with rounded bottoms but the tubes were later redesigned with flat bottoms. (I assume that the rounded bottoms were first because the bubble on the packaging is rounded, which wouldn't make sense otherwise.) The reason may be that the rounded tubes, although much cooler and more durable, were impossible to display. As a side note, the top stopper of the rounded tube had a nifty Germs logo! Oochi and Muggy, shown below, are the only figures I have with the rounded test tube bottom.
The line was pretty short-lived as you might imagine. The toys, although very imaginative, didn't particularly lend themselves to action-oriented play. But I'm sure that if it were more popular, some pretty cool lab-oriented playsets could be made... and maybe even a board game that interacted with the toys in which the purpose would be to infect a person with your germs (all of which only ever existed in my delusional mind, of course)! But alas, 'twas not to be and the Germs ended with only a single 12-figure line.
This was a line that I totally forgot about, and was recently reminded of them with a trip to the Virginia Natural Bridge Toy Museum. I have pics of eight Germs below along with pics of the card back illustrations and various other stuff.
Huppahickasillia, Bubblebuppilitus, Hackahackasilliae
Germs carded close-ups
Rounded Test Tube Stopper Top