Project Lead(s): D. Bohle
Issue
Onchocerciasis, also known as river blindness, is a disease caused by infection with the parasitic worm Onchocerca volvulus. It is a major cause of blindness in many African countries, with about 500,000 blind or visually impaired as a result of the disease. It also causes a skin disease, with depigmentation and severe, unrelenting itching.
Current diagnosis methods are slow, invasive and not sensitive, and the painful process of skin snip biopsy makes many individuals avoid testing.
Solution
The objective of this project was to develop a rapid, in situ, less-invasive method to test for roundworm microfilariae in the skin of onchocerca-infected individuals, using fluorescent dyes.
To test this concept, new and previously described fluorescent dyes were tried against both microfilaria and adult worms.
These trials were conducted both in the lab and in situ in Cameroon with freshly isolated parasites.
Outcome
The proof-of-concept experiments were partially successful, as dye uptake by all of the parasites was demonstrated, both in vitro and in the skin. Their detection in skin, however, was complicated by extensive scattering of the light by the skin.
Initial experiments in preparation for field work demonstrated that dyes were also taken up by the microfilariae of Brugia malayli, which causes elephantitis in humans.
The project received $15,000 from the Quebec Government through the Quebec FQRNT Mobility Program.
