Fig. 4. correlation between IgG titres determined by ELISA-soluble Schistosoma mansoni adult worm antigen preparation (SWAP) (A) and ELISA-soluble S. mansoni egg antigen (SEA) (B) with the eggs count after 18 slides of Kato-Katz for endemic area positive patients. epg: eggs per gram of faeces; OD: optical density.