摘要
目的对今年2月我国发生的人感染H7N9禽流感流行分布和起源进行分析。方法应用描述性研究,对WHO和我国资料以及相关疾病流行史进行比较。结果 5种异常:流行强度:3个月内病例多,涉11个省市;而人H5N1禽流感7个月仅18例;地区和传染源栖居点:人禽流感(h-AI)应发生在野或家禽已有该型病毒流行之地;虽在韩蒙多国检出H7N9 AIV,但我国从未见;新H7N9 AIV也限在3活禽市场;年龄分布:发病平均年龄为59.02岁,主要原因是h-H7N9 AIV对我国为全新病毒:老人毫无特异免疫,非特异免疫低下,易感性最高;传播方式异常:已有3起家庭聚集,其中1起存在有限的人传人;而人H5N1禽流感首发后7年才有。结论人H7N9禽流感和人禽流感甚至人兽共患病的流行自然史明显不符,不能排除h-H7N9 AIV异常起源之可能。
Objective An epidemic of human infection with H7N9 avian influenza virus [h（n）-H7N9 AIV] has breaking out in China in February,2013. The aim of the study is to comprehensively explore h-H7N9 AI and its origin. Methods The data from WHO, Chinese government and the papers of relevant diseases have been analyzed by descriptive epidemiology. Results The results showed that comparing with only 18 cases of h-H5N1 AI during 7 months, an unusual incidence with 131 cases of h-H7N9 AI in 11 provinces within 3 months were determined, and an unusual occurrence loca- tion and inhabited areas of n-H7N9 AIV were identified by the presence of H7N9 AIV in many countries including Korea and Mongolia, only with the exception of China, and by n-H7N9 AIV only limited to three live poultry markets. Also, a very unusual age distribution, with mean age of 59. 02 years, is observed and the main reason was that the old man with low innate immunity had no specific immunity and the highest susceptibility because H7N9 AIV was a new virus for Chinese, and comparing with occurrence of family clusters in same family after 7 years for h-H5N1 AI outbreak, an unusual transmis- sion mode was proved by three family clusters in the first h-H7N9 AI epidemic in the world and limited human - to - human transmission might be existed in one family of them. Conclusions The unusual distributions suggest that h-H7N9 AI markedly differs from h-AI even human zoonotie diseases for natural epidemiologieal history and its unusual origin cannot be ruled out.
出处
《中华疾病控制杂志》
CAS
北大核心
2013年第8期645-650,共6页
Chinese Journal of Disease Control & Prevention
关键词
禽流感
流感
人
流行病学研究
Avian flu
Influenza, human
Epidemiologic studies
