Loiasis (African eyeworm), caused by the filarial parasite Loa loa transmitted by deer flies of the Chrysops genus predominant in the rainforest of Central and West Africa. It presents with episodic swelling known as Calabar swellings, which may be less visually prominent but still painful in darker-skinned individuals. The adult worms can sometimes be seen migrating across the eye, causing irritation but usually not blindness. Treatment typically includes diethylcarbamazine (DEC) to kill the adult worms, and in some cases, albendazole is used to manage severe infections, with careful monitoring to prevent complications.