Yoshiki Kawamura   Fumihiko Hattori   Yuki Higashimoto   Kei Kozawa   Tetsushi Yoshikawa   
Vaccine 39(21) 2901-2905 2021年5月
OBJECTIVE: The aim of this study was to elucidate vaccine effectiveness (VE) during varicella outbreaks in schools and nurseries in Japan. METHODS: An outbreak was defined as emergence of three or more cases of varicella within 21 days at the same...