Paragonimus westermani

Paragonimus westermani, the Japanese or oriental lung fluke, is a parasitic flatworm and the most common lung fluke to infect people, causing the lung disease paragonimiasis. The adult looks like a reddish-brown coffee bean, roughly seven to sixteen millimetres long, and lives paired in capsules in the lungs of felines, other carnivores and humans. Eggs pass out in sputum or faeces, hatch in fresh water and enter freshwater snails, then move on into freshwater crabs or crayfish, where they encyst. People and other mammals are infected by eating raw, pickled or undercooked crustaceans. The species is found across southeast Asia and Japan, was first noticed in tigers that died in European zoos in 1878, and is named after the Amsterdam zookeeper Pieter Westerman.