 In 1976, the name ""Pneumocystis jiroveci"" was proposed for the first time, to distinguish the organism found in humans from variants of "Pneumocystis" in other animals.The organism was named thus in honor of Czech parasitologist Otto Jirovec, who described "Pneumocystis" pneumonia in humans in 1952.After DNA analysis showed significant differences in the human variant, the proposal was made again in 1999 and has come into common use.