We used samples from a trial of praziquantel treatment-effects on vaccine responses in Schistosoma mansoni (Sm)-endemic Ugandan islands, measuring intestinal fatty acid-binding protein 2 (I-FABP2), lipopolysaccharide-binding protein, anti-endotoxin core antibodies (EndoCab), soluble CD14 (sCD14) in plasma, and faecal lipocalin-2, occult blood (FOB), and calprotectin (fCAL), and evaluating their associations with baseline helminth infection, praziquantel treatment, and responses to BCG, yellow fever, typhoid, HPV, and tetanus-diphtheria vaccines. The gene discussed is FABP2; the disease is diphtheria.