<prompt> A 20-year-old male patient presents to the OPD with complaints of fever, intermittent abdominal pain, and dysuria. He gives a history of swimming in the freshwater lake 10 days back. Urine microscopy shows the following. Which of the following is the causative agent?Schistosoma mansoniSchistosoma hematobiumSchistosoma japonicumSchistosoma mekongi  <response>: The given clinical picture along with the history of swimming and the image showing egg which is non-operculated with the terminal spine at one pole are suggestive of infection with Schistosoma hematobium. The eggs of Schistosoma hematobium are ovoid, non-operculated, with a brownish-yellow transparent shell, carrying a terminal spine at one pole. Species differentiation of Schistosoma can be done based on the location of the spine as follows: Terminal spine: Schistosoma hematobium Lateral spine: Schistosoma mansoni Rudimentary lateral spine: Schistosoma japonicum Reference: Paniker;s Textbook of Medical Parasitology 8th edition 