A little less than 100 years ago, officials around Japan initiated a campaign to address what the government considered to be a grave threat — flies.

Yes, flies. Until then, flies had been considered to be rather harmless. Somewhat annoying, yes, but certainly not a threat of any type. However, a growing chorus of public officials began to see the insects as spreaders of disease, so laws were amended and campaigns were organized.

In Tokyo, the municipal government sponsored an annual "Swat the Fly Day" and offered money and coupons in exchange for dead flies. A philanthropist named Seiko Goto offered a bounty of one sen (¥0.01) for every fly produced. People around Japan actually competed to record the most kills, and during each summer of those worrisome years, over 100 million dead flies were reportedly collected throughout Tokyo.