The First Human Case in Mexico of Conjunctivitis Caused by the Avian Parasite, Philophthalmus lacrimosus

Species of Philophthalmus parasitize primarily the eyes of wild and domestic birds. A variety of mammals, including humans, occasionally serve as the intermediate as well as the definitive hosts for this parasite, although human cases are extremely rare. Here, we report a case of human conjunctivitis caused by an infection with Philophthalmus sp. in Mexico. The patient was a 31-yr-old male who visited an ophthalmologist in Los Mochis, Sinaloa, Mexico, because of a foreign-body sensation in his left eye for 2 mo. A small live parasite was found in the connective tissue of the bulbar conjunctiva and was removed surgically under local anesthesia under ophthalmoscopic observation. The parasite was identified morphologically as Philophthalmus lacrimosus Braun, 1902. This is the first case of human philophthalmosis in Mexico and, to our knowledge, the first human case of P. lacrimosus infection in the world.