Male and female L4 stages, adult worms

male and female L4 migrating in the skin, adult worms in the nodule (adapted from Wenk & Renz, 2003)

Little is known about the fate of the infective larvae when they are deposited in the skin: Only a few of them develop to the adult stage. This development takes about 12 months. The molt from the L3 to the L4 stage takes places rather soon, only about 10 days after transfer to the vertebrate host. This moulting can be achieved with L3, kept in-vitro.

female Onchocerca adult worm (A. Renz, original)