What condition involves fly infestation with larvae and is commonly known as screwworm?

Myiasis is the correct answer because it specifically refers to a condition characterized by the invasion of live human tissue by the larvae of flies. The term "screwworm" is commonly associated with certain types of myiasis, primarily caused by the larvae of Cochliomyia hominivorax and other fly species that lay their eggs in open wounds or sores. As the larvae develop, they feed on the host's tissue, leading to pain, infection, and in severe cases, can pose serious health risks.

This condition is distinct from malaria, which is caused by parasites transmitted through the bites of infected mosquitoes, and filariasis, which is caused by parasitic worms transmitted by certain vectors like mosquitoes. Colorado tick fever, on the other hand, is a viral infection transmitted by ticks and does not involve the larvae of flies. Myiasis specifically highlights the ecological interaction between larvae and their host, making it a unique and important phenomenon in medical and environmental health contexts.