Cooties is a fictitious childhood disease, commonly represented as childlore. It is used in the United States, Canada, Australia, New Zealand, and the Philippines as a rejection term and an infection tag game (such as Humans vs. Zombies). It is similar to the British 'dreaded lurgi', and to terms used in the Nordic countries, in Italy, India and Iraq.A child is said to "catch" cooties through close contact with an "infected" person or from an opposite-sex child of a similar age.
https://en.m.wikipedia.org/wiki/Cooties

Cooties is also a 2014 American zombie comedy film directed by Jonathan Milott and Cary Murnion from a screenplay that was written by Ian Brennan and Leigh Whannell. It stars Elijah Wood, Alison Pill, Rainn Wilson, Jack McBrayer, Whannell, Nasim Pedrad, Brennan, and Jorge Garcia as a group of elementary school employees who fight to survive an outbreak among students that turn them into aggressive zombies when someone eats chicken nuggets that contain a virus.
Well worth watching