1. Department of Parasitology, Seoul National University College of Medicine, and Institute of Endemic Diseases, Seoul National University Medical Research Center, Seoul 110-799, Korea.
2. Department of Internal Medicine, Ilsan Baik Hospital, Inje University College of Medicine, Goyang 440-410, Korea.
3. Department of Parasitology, College of Medicine, Inha University, Inchon 400-712, Korea.
4. Department of Parasitology, College of Medicine, Dankook University, Chonan 300-714, Korea.
5. Department of Parasitology, College of Medicine, Seonam University, Namwon 590-170, Korea.
6. Department of Parasitology, Yonsei University College of Medicine, Seoul 120-752, Korea.