|Species:||M . streptocerca|
Mansonella streptocerca, (formerly Diptalonema streptocerca), is the scientific name of a human parasitic roundworm causing the disease streptocerciasis. It is a common parasite in the skin of humans in the rain forests of Africa, where it is thought to be a parasite of chimpanzees, as well.
Mansonella streptocerca is one of three filarial nematodes that cause subcutaneous filariasis in humans. The other two filarial nematodes are Loa loa (the African eye worm), and Onchocerca volvulus (river blindness).
The worm is distributed across West Africa.
The contraction of an M. streptocerca infection can be better understood through an understanding of its life cycle. The life cycle involves two stages: one involving a midge (genus Culicoides) and another involving a human host. First, a midge ingests a blood meal from a human host. This allows third-stage filarial larvae to enter the bite wound. Once inside the dermis, the larvae develop into adults, usually less than 1 mm from the surface of the skin. In terms of size, the females can reach 27 mm in length, whereas the males can be around 50 μm in diameter. These adults then produce nonperiodic microfiliariae, which habituate in the skin, but can also travel to the peripheral blood. These microfilariae are then passed onto the midge when the insect ingests a blood meal. Following the blood meal, microfilariae travel to the midge’s midgut through the hemocoel to the thoracic muscles. In the thoracic muscles, the microfiliariae develop into first-stage larvae, followed up by third-stage development. In this latter stage, the larvae travel to the midge’s proboscis, where it can subsequently infect another human host upon another blood meal ingestion. 
The adult form of M. streptocerca was discovered by Dr. Wayne M Meyers while working as a medical missionary in Africa.
- foundations of parasitology, 8th ed, p 473-474... from Meyers, 2000, in Hunter's tropical medicine and emerging infectious disease 8th ed.