LAUSR

The human fi larial nematode Mansonella ozzardi occurs widely in the Neotropical region from southern Mexico to northwestern Argentina. It causes mansonellosis and is transmitted by black fl ies of the genus Simulium and biting midges of the family Ceratopogonidae. The embryonic unsheathed micro fi lariae with sharp, unnucleated tails are detectable in the blood (and occasionally in the skin) 1 day after being released by the fertilized adult female worms. After being ingested by a vector, the micro fi lariae reach the insect ’ s thoracic musculature through the hemocoel and develop, after two moults, into infective L3 larvae that migrate to the head and mouth parts of the vector. Cross-sectional surveys in endemic areas show an increase in both M. ozzardi prevalence and micro-fi larial load with patients ’ age until they reach their 60s. Most cases of mansonellosis appear to be asymptomatic, but mild symptoms and a recently recognized ocular pathology have been associated with this infection.