<prompt> A 20 year old man presents with swelling of left lower limb and hydrocoele. All of the following may be the causative agent EXCEPT:Brugia malayiBrugia timoriaWuchereria bancroftiOnchocerca volvulus  <response>: Ans. d Onchocerca volvulusRef: Diagnostic medical parasitology 3rd275, Park 19th 221 Onchocerca volvulus results in river blindness and subcutaneous nodules. Lymphatic filariasis covers infection with three closely related nematode worms - W.Bancrofti, B. Malayi and B. timoria. All three infections are transmitted to man by the bites of infective mosquitoes. All three parasites have basically similar life cycles in man- adult worms living in lymphatic vessels whilst their offspring, the microfilariae circulate in peripheral bloodand are available to infect mosquito vectors when they come to feed.Also Know Diethylcarbamazine DEC is the drug of choice for filariasis. Ivermectin is the drug of choice for Onchocerca volvulus 