This is a true story reported on CNN

A woman was working in a post office in California.

One day she licked the envelopes and postage stamps instead of using a
sponge. That very day the lady found a cut on her tongue. A week later,
she noticed an abnormal swelling of her tongue. She went to the doctor,
and they found nothing wrong. Her tongue was not sore or anything. A
couple of days later, her tongue started to swell more, and it began to
get really sore, so sore, that she could not eat. She went back to the
hospital and demanded something be done. The doctor took an x-ray of
her
tongue and noticed a lump. He prepared her for minor surgery. When the
doctor cut her tongue open, a live cockroach crawled out!!!!

There were cockroach eggs on the seal of the envelope. The egg was able
to hatch inside of her tongue, because of her saliva. It was warm and
moist...