Nagao Kazuyoshi, Mori Toshihiko, Sawada Chieko, Sasakawa Chiiko, Kanezaki Yoshiko
Division of Public Health Sciences, Tokushima Prefectural Institute of Health and Environmental Sciences, Tokushima 770-0941, Japan.
Jpn J Infect Dis. 2007 May;60(2-3):149-50.