[1] Minist Hlth & Welf, Div Preparedness & Emerging Infect Dis, Ctr Dis Control, Taipei, Taiwan
[2] Minist Hlth & Welf, Off Prevent Med, Ctr Dis Control, Taipei, Taiwan
[3] Natl Taiwan Univ, Inst Epidemiol & Prevent Med, Coll Publ Hlth, Taipei, Taiwan
[4] Minist Hlth & Welf, Ctr Res Diagnost & Vaccine Dev, Ctr Dis Control, Taipei, Taiwan