Loa loa: The African Eye Worm
A parasite is an organism in or on another living organism obtaining from it part or all of its organic nutriments, commonly exhibiting some degree of adaptive structural modifications, and causing some degree of real damage to its hosts‘ (Thomas, Renaud, and Guegan, 2005). One of the many parasites is the filarial African eye worm, Loa loa. Loa loa belongs to class Secernentea, subclass Spiruria, order Spirurida, super family Filarioidea, and family Onchocercidae. These parasites are located in the areas of the rain forest near equatorial Sudan and in West and Central Africa. Loa loa has a simple head with no lips, a long, slender body, a rounded tail, and eight cephalic papillae (Loa loa). Besides the head and tail, the cuticle is covered with irregular, small bosses. Female Loa loa is generally five to seven centimeters long and the male is from two to three and a half centimeters long. Loa loa is asymmetrical meaning they have three pairs of preanal and five pairs of postanal papillae (Loa loa). The spicules of Loa loa are uneven and dissimilar. The vulva of the female is about two and a half millimeters from the anterior end and the tail is about 265-300 um long (Loa loa). Microfilariae of this parasite possess a sheath that does not stain with Giemsa but is with Delafield’s haematoxylin and is stain blue-gray. Loa loa is a parasite that lives in humans and other primates, transmitted by mango flies and horse flies. They generally live under the human skin and infrequently crawl across the surface of the eye (Vodopich and Moore, 2005). Life Cycle:
Loa loa is a filarial nematode that is transmitted to humans by Chrysops flies; mango and horse flies. Once inside the human body, the infective larvae develop into a mature adult in a slow process. This process can take about a year. During this time, the larvae lives and move around in the layers of the human skin. During the growth and development...
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Vodopich, Darrell S. and Moore, Randy. 2005. Biology Laboratory Manual, Seventh Edition. The McGraw-Hill Companies, Inc. The United States
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