Studies on Bancroftian filariasis in Liberia, West Africa. IV. Notes on side effects observed during a diethylcarbamazine treatment campaign in a rural area endemic for Wuchereria bancrofti and Onchocerca volvulus.

464 persons of whom 189 proved to be infected with microfilariae of Wuchereria bancrofti and/or Onchocerca volvulus were examined for adverse reactions due to diethylcarbamazine, which was administered during a filariasis control campaign. Persons older than 20 years of age were significantly more affected than younger persons and men showed distinctly more side effects than women. The most frequent complaints were skin reactions followed by gastrointestinal complications. The significantly highest rate of adverse reactions was observed in persons being infected with microfilariae of O. volvulus, whereas no significant difference was registered between side effect rates of bancroftian microfilaria carriers and non-infected persons. It is concluded that in areas where both filarial species are endemic, infections with O. volvulus are a limiting factor for the control of bancroftian filariasis by means of mass treatment with diethylcarbamazine.