Correspondence: Masao Kamiya
Hirofumi Sakai
Yuzaburo Oku
Masao Kamiya
Department of animal disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060, Jaoan.

Ramiro Malgor
Isabel Basmadjian
Carlos Carmona
Unidad de Biologia Parasitaria, Instituto de Higiene, Facultad de Medicina, Universidad de Republica Oriental del Uruguay, Avenida Dr. Alfredo Navarro 3051, Montevideo, Uruguay.

Rosario Gallardo
Comision Honoraria de Lucha contra la Hidatidosis, Tacuarembo, Uruguay

Hiroshi Sato
Department of Parasitology, Hirosaki University School of Medicine, Hirosaki 036, Japan.