South Asian Journal of Parasitology

Non-Governmental Organizations in collaboration with the National Program for the Fight against Onchocerciasis ‘‘PNLO’’, are well engaged in the fight against filariasis in the Democratic Republic of Congo.

This study, conducted at the Buta General Reference Hospital, aims to search for the Loa loa microfilaria in blood donors during the night in order to verify the theory that this microfilaria species was exclusively observed during the day (at daytime periodicity).

The study involved 45 donors (family and volunteer donors) parasitized by microfilariae. The majority of them were Loa loa, the predominance of which came from night-time collection between 18:00 and 22:00. Donors from the primary activity sector (agriculture, hunting and fishing) [81.5%], those in the 18-27 age group (37.1%) and men (63%) were more infested with microfilaria. Life in rural areas (66.7%) was one of the factors favouring microfilaria infestation, taking into account the above-mentioned vital activities of the population living there. The markers detected in donors outside the microfilaria tested were hepatitis B antibodies (HBsAg) (6.5%) and HIV antibodies (8%).

We have observed that the periodicity of the parasite (Loa loa) which is (known) diurnal can be reversed depending on the activity of the parasitized person; depending on whether he or she works during the day or at night. There is also the hypothesis that the period of activity of the vector selects the periodicity of the parasite.