Which parasite is a worm transmitted by mosquitoes?

• A. Tapeworm
• B. Flea
• C. Heartworm
• D. Coccidia

Answer: (C)

Mosquitoes can carry a worm that causes heartworm disease. The parasite is a roundworm (a nematode) called Dirofilaria immitis. When an uninfected mosquito bites an infected animal, it picks up larvae and later transmits them to another animal. The larvae migrate to the heart and pulmonary arteries, where they mature and cause heart-llung disease. This is different from tapeworms, which are flatworms transmitted when an animal ingests infected fleas or other intermediate hosts, not by mosquito bites. Fleas aren’t worms themselves, though they can be carriers for tapeworms. Coccidia are protozoa spread through fecal-oral routes, not via mosquitoes. So the worm transmitted by mosquitoes is heartworm.