This cache is part of a greater mystery cache called AlienRobotMonkeyJediZombieDragonPirateNinjaWiard!. Solve the preliminary puzzle on that cache for help understanding what you are supposed to do.
Dr. Oxy was thwarted by the group above, which included a number of geocachers. Because he is so schizophrenic, he is back to his old ways of wanting to provide clues for you to avoid being overtaken by the Zombie Apocalypse, yet still hoping you won't figure it out because he wants to eat you.
It turns out Dr. Oxy escaped from the room when a thrill seeker forgot to lock the door upon escaping. Dr. Oxy immediately began contaminating as many people as he could around Central Ohio, but realized he had a certain affinity for those geocachers in the picture above.
He decided to hide a list in a test tube where geocachers could place their names. Then, when Zombies came by the location for a little snack, they would be able to read the latest list of people not to eat. A couple had to perish to create this snacking location - but hey, they were going to get eaten anyway... so don't you feel bad!
Be aware of your surroundings - you never know WHAT Dr. Oxy might have placed in the tube, and that "food nearby" attribute on the geocaching page isn't talking about McDonald's!