Autoinfection is seen with -

Ans. is 'b' i.e., Strongyloides Autoinfection -The term autoinfection refers to the ability of certain parasites, particularly helminth to establish life cycle within the host, eliminating the need for an intermediate stage and secondary host.It can also be defined as reinfection from a parasite or microbe that are present within the bodyParasites causing AutoinfectionParasiteMethod of causing auto-infection1. Capillaria philippinensisLiberated larvae penetrate intestinal mucosa2. Cryptosporidium parvumThin-walled oocysts can reinfect the same person3. Enterobius vermicularisRetrograde to caecum. Can also be carried by contaminated hands to mouth.4. Hymenolepis nanaEggs hatch in the same person's intestine, onchospheres enter mucosa to develop into cysticercoid larvae. These in turn migrate back into intestine to develop into adults.5. Strongyloides stercoralisEggs hatch to liberate rhabditiform larvae that immediately develop into filariform larvae. These larvae penetrate intestinal mucosa.6. Taenia solium (cysticercosis)Reverse peristalsis leading to entry of gravid proglottids/eggs into stomach. Can also be carried by contaminated hand to mouth.RememberWorms which does not multiply in hostA. duodenaleEnterobius vermicularisW. bancroftiWorms that crawl outEnterobius vermicularisT. saginata