广东省人感染禽流感疫情流行病学特征分析

Epidemiological features of human infections with avian influenza virus,Guangdong Province

目的分析广东省人感染不同亚型禽流感疫情流行特征。方法回顾性收集广东省1998―2014年期间报告发生的人禽流感确诊病例信息,采用描述性流行病学方法分析病例的流行病学特征和暴露因素。结果 1998—2014年广东省共报告人禽流感确诊病例130例,其中H5N1病例4例、H5N6病例1例、H5亚型1例、H7N9病例113例、H9N2病例11例;死亡43例,病死率为33.08%。81.54%(106/130)病例发生在1—3月和12月,67.69%(88/130)病例发生在珠江三角洲地区。男性81例,女性49例,男女性别比为1.65∶1;≥55岁中老年病例62例,占48.44%(62/128)。92.31%(120/130)病例有明确的活禽相关暴露史,其中从事禽类相关职业占8.33%(10/120),禽类接触暴露占41.67%(50/120),活禽市场环境暴露占50.00%(60/120)。结论广东省人禽流感疫情在冬春季高发,同时呈现一定的区域聚集性;禽类接触和禽类市场环境暴露是主要的感染方式。

Objective To understand the epidemiological features of human infection with avian influenza virus in Guangdong Province. Methods Demographic and epidemiologic data on human cases reported during 1998 -2014 were collected and analyzed. Epidemiological characteristics and exposure fac- tors of the cases were analyzed by using the method of descriptive epidemiology. Results A total of 130 cases infected with avian influenza A viruses were reported from 1998 to 2014, including 4 cases of H5N1, 1 case of H5N6, 1 case of H5 subtype , 113 cases of H7N9,11 cases of H9N2, 43 deaths, with a mortality rate of 33.08% ; 81.54% （106/130） of cases occurred from January to March and in December, and 67. 69% （88/130） occurred in the Pearl River Delta area. Among all the cases, 81 were male and 49 were fe- male, with a male to female ratio of 1.65：1 ; 48.44% （62/128） of cases aged 55 years and over, 92.31% （120/130） had clear exposure to live poultry; 8.33% （10/120） engaged in poultry related occupations, 41.67% （50/120） contacted with poultry, and 50.00% （60/120） had exposure to wet markets with live poultry. Conclusion The epidemic peaks of human infections with avian influenza virus in Guangdong ap- peared in winter and spring, with certain regional clusters. The main source of infection was exposure to the live poultry and wet markets with live poultry.