MMWR Morb Mortal Wkly Rep. 1990 Dec 14;39(49):902-3.
Influenza activity in the United States is monitored by CDC through surveillance systems developed in cooperation with state and local health departments; in addition, CDC receives reports of worldwide influenza activity from international World Health Organization (WHO) collaborating laboratories and WHO, Geneva. This report summarizes influenza activity in the United States and worldwide for April through November 1990.
美国疾病控制与预防中心（CDC）通过与州和地方卫生部门合作建立的监测系统对美国的流感活动进行监测；此外，CDC还从世界卫生组织（WHO）的国际合作实验室和位于日内瓦的WHO收到全球流感活动报告。本报告总结了1990年4月至11月美国及全球的流感活动情况。
