Loa /lo′ə/ , a genus of nematodes of the superfamily Filarioidea. L. loa is a threadlike species 2.5 to 5 cm long found in West Africa. It inhabits the subcutaneous connective tissue of the human body and is seen especially as an eye worm about the orbit and under the conjunctiva. It causes itching and occasionally edematous swellings (Calabar swellings). The immature forms or microfilariae are diurnal, being found in the peripheral circulation in greatest concentrations during the day.
