1990s report of fatality rate ofaT F atality Rate 30 口<1year-old year-old 20 10 0 City Countryside J. Chinese Pediatr 1995, 33(7)1990s report of fatality rate of AT Fatality Rate ％ 0 10 20 30 40 City Countryside ％ <1 year-old 1~3 year-old J. Chinese Pediatr 1995, 33(7)