A rare infestation of the nasal cavities, windpipe, lungs, liver, or spleen by the nymphs of the parasitic arthropod Porocephalus. Man becomes infected on consumption of water or uncooked vegetables contaminated with the parasite’s eggs. There may be some abdominal pain while the parasite is in the gut but generally there are no symptoms. Porocephaliasis has been occasionally reported in central Africa.