[1] Aichi Med Univ, Sch Med, Dept Parasitol, Nagakute, Aichi 4801195, Japan
[2] Nagoya Univ, Environm Med Res Inst, Dept Endocrinol & Metab, Nagoya, Aichi 464, Japan
[3] Rajshahi Med Coll, Dept Microbiol, Rajshahi, Bangladesh
[4] Rajshahi Med Coll, Dept Med, Rajshahi, Bangladesh
[5] Kochi Med Sch, Dept Parasitol, Kochi, Japan