During her stay in Ngaoundéré, Silke van Hoorn from the Bernhard-Nocht-Institut in Hamburg isolated about 2 million of Onchocerca ochengi microfilariae from the skin of cattle (skin samples from the slaughterhouse) and kept them in-vitro to obtain excretory-secretory products (ESPs) for further bio-molecular examinations. These microfilariae had to be separated from those of Onchocerca gutturosa, which also dwell in the skin. This is difficult.
Therefore another option was also tried by Achille Paguem, a Camerooninan student working in our lab: To isolate living microfilariae from the uterus of gravid female worms. Although those intrauterine (i.u.) microfilariae may not be fully mature, they are free from non-O. ochengi contamination. Achille has harvested about 800.000 i.u. microfilariae up-to-now.