Long-term treatment of onchocerciasis patients from the Liberian rain-forest with low doses of diethylcarbamazine citrate after complete nodulectomy.

60 completely nodulectomized volunteers from the Liberian rain-forest were given an initial treatment with diethylcarbamazine citrate (DEC-C) for one week with gradually increasing doses up to a total of 1.1 g per patient. A long-term treatment followed with 50 mg DEC-C per week for 12 months. Immediately after the initial treatment the mean microfilarial density decreased to 4% to 6% of the pre-treatment level. After one year the microfilarial density had again increased to 12% to 29% of the pre-treatment level. Although the intake of the weekly 50 mg DEC-C was in no case regular, the microfilarial densities could be kept at a low level throughout the trial. However, even with the combined treatment--preceding nodulectomy and long-term trial with DEC-C--it was not possible to get the patients free from microfilariae.