After a trip to Belize this summer, a Colorado man sought medical advice when he discovered several bumps had appeared on his scalp.

Aaron Dallas thought the lumps might have been bites or shingles, but he was in for a surprise when doctors told him the bumps were moving – and he had five live botfly maggots inside his head.

"I'd put my hand back there and feel them moving,” Dallas said. “I thought it was blood coursing through my head. I could hear them. I actually thought I was going crazy.”

Adult botflies are larger and more aggressive than European flies.

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