Survival of Loa loa following transplantation from drills (Mandrillus leucophaeus) into jirds (Meriones unguiculatus): parasitology and pathology.

Two drills infected with Loa loa maintained a microfilaraemia for four and a half years ranging from less than 1 mf/100 microliters to 1150 mf/100 microliters. No significant tissue reactions to the adult worms were seen at autopsy. Adult worms were transplanted into the peritoneal cavities of naive jirds when a persistent microfilaraemia first developed by 17 days. Retransplantation of adult worms into naive jirds produced a microfilaraemia and microfilariae in the peritoneal cavities of three out of five animals. These three animals were all negative for circulating parasites by eight and a half months. The tissue reactions to the worms in the jirds are described, including a granulomatous response surrounding adults and a myositis involving microfilariae.