Action of diethylcarbamazine in vitro on infective larvae of Wuchereria bancrofti.

Infective larvae of Wuchereia bancrofti were obtained from laboratory infected Culex fatigans and maintained in serum containing diethylcarbamazine. There was no difference in the survival time of these larvae and larvae maintained in control serum without diethylcarbamazine. In one of the three experiments reported the survival time of the larvae was much longer than in the other two experiments. It is suggested that this may have been due to the presence of filarial antibodies which killed the larvae in two of the sera used. In the serum which did not contain antibodies, the larvae survived very much longer.