Relapses of enteric fever induced by Schistosoma intercalatum have been observed to occur in central Africa. In Libreville, Gabon, 70 children (ages, 2.1-15.9 years) who were seronegative for human immunodeficiency virus and were hospitalized for septicemic salmonellosis underwent rectal biopsy for diagnosis of S. intercalatum infection. A nontyphoidal Salmonella species was isolated from 53 of the 70 patients: Salmonella typhimurium in 14 cases; Salmonella enteritidis in 7 cases; Salmonella galiema in 4 cases; Salmonella arizonae in 3 cases; and other species in 25 cases. Schistosomal eggs were present in the rectal mucosa of 48 (90.6%) of these 53 patients, in 11 (64.7%) of 17 patients with septicemia due to Salmonella typhi or Salmonella paratyphi, and in 21 (38.2%; P < .001) of 55 controls. Clinical symptoms were not different among patients coinfected with S. intercalatum and nontyphoidal Salmonella vs. those with enteric fever. Treatment with antibiotics induced apyrexia only after administration of antiparasitic therapy in 30 patients. These data strongly suggest interactions between S. intercalatum and Salmonella in infected children with clinically severe nontyphoidal salmonellal septicemia.