A recently developed IgG-ELISA using the recombinant cysteine protease antigen (21 kDa) derived from cDNA of the Paragonimus skrjabini juvenile stage was reported to have a sensitivity of 95.5% and no cross-reaction with antibodies from the other human diseases in the study by Yu et al. [19], i.e. echinococcosis granulosus, taeniasis solium, schistosomiasis japonicum and trichinellosis spiralis [19]. This evidence concerns the gene CTSB and echinococcosis.