Studies on the Morphology and Life-History ofStrongyloides mirzain.sp. from Snakes in India

Abstract

In 1985, the writer in collaboration with Prof. M. B. Mirza describedStrongyloidesfrom John's Sand-boa (Eryx johnii) in Aligarh and assigned it toS. stercoralis, creating for its reception a new variety,S. stercoralis var. eryxi.During July and August, 1950, while examining certain snakes at Hyderabad for helminth parasites, the writer found thatStrongyloidesinfection was very common in the Rat-snake.Ptyas(Zamenis)mucosus, for almost all the snakes examined were found infected. In light infections not more than a few, ten to fifteen worms, were obtained from a single host, but as many as 100 to 125 specimens were collected from heavily parasitized snakes. It was also observed that though they may be found throughout the length of the oesophagus and the intestine, the seat of heaviest infection is the duodenum of the host.It seemed rather strange that one and the same species should parasitize a reptile as well as a mammal so a detailed study of the worm, both in its parasitic and free-living generations, was undertaken with a view to determining definitely whether, as previously believed, it is identical with the human wormStrongyloides stercoralis. As a result of this study the writer has come to the conclusion that the species infesting certain snakes in India is not identical with the human worm,S. stercoralisor any other species of the genus hitherto described.