Flea larvae are an intermediate host for which of the following?

Flea larvae are an intermediate host for which of the following?

• A. Dipylidium caninum
• B. Taenia pisiformis
• C. Hymenolepis nana
• D. Spirocerca lupi

Answer: (A)

Flea larvae serve as the intermediate host for Dipylidium caninum, a tapeworm of dogs and cats. In this life cycle, the tapeworm’s eggs are shed in the animal’s feces as proglottids. Flea larvae ingest these eggs and develop them into cysticercoids inside the flea. When a dog or cat chews or grooms and swallows an infected flea, the cysticercoid is released in the intestine and matures into an adult tapeworm, producing more proglottids that are excreted in feces. The other parasites rely on different intermediates: Taenia pisiformis uses rabbits as the intermediate host; Hymenolepis nana can transmit directly to humans or rodents via ingested eggs and can involve certain insects as intermediate hosts but not specifically flea larvae; Spirocerca lupi uses beetles and other arthropods as intermediate hosts.

Flea larvae serve as the intermediate host for Dipylidium caninum, a tapeworm of dogs and cats. In this life cycle, the tapeworm’s eggs are shed in the animal’s feces as proglottids. Flea larvae ingest these eggs and develop them into cysticercoids inside the flea. When a dog or cat chews or grooms and swallows an infected flea, the cysticercoid is released in the intestine and matures into an adult tapeworm, producing more proglottids that are excreted in feces.

The other parasites rely on different intermediates: Taenia pisiformis uses rabbits as the intermediate host; Hymenolepis nana can transmit directly to humans or rodents via ingested eggs and can involve certain insects as intermediate hosts but not specifically flea larvae; Spirocerca lupi uses beetles and other arthropods as intermediate hosts.