[Simultaneous infection of Mastomys natalensis with Dipetalonema witei and Litomosoides carinii (author's transl)].

Mastomys natalensis that has been described by Lämmler et al. (1968) as suitable host for Litomosoides carinii can also serve as final host for Dipetalonema witei. At the end of the prepatency period the microfilaraemia increased as rapidly in Mastomys as in the original final host Meriones persicus. Maximal microfilaraemia was observed earlier in Mastomys (120 days p.inf.) than in Meriones (250 days p.inf.). Accordingly microfilariae counts decreased more rapidly in Mastomys. The maximal counts found in Mastomys was 78000 microfilariae/ml blood, which is 3.2 times less than in M. persicus. Furthermore it could be demonstrated that a simultaneous experimental infection of Mastomys with D. witei and L. carinii in possible. The course of microfilaraemia and the number of macrofilariae were comparable in mono- and simultaneous infections for both species of filariae. The macrofilariae of D. witei began to die earlier than those of L. carinii both in mono- and in simultaneous infections. The percentage of dead macrofilariae was 3.8% 110 days p.inf., and 13.1% 130 days p.inf. respectively. Therefore, chemotherapeutic experiments should be terminated and evaluated about 110 days p.inf.