Importance The Sabin-strain inactivated poliovirus vaccine (IPV) may be a tool for polio outbreak response in certain situations. Objective To investigate the response to a type 2 vaccine-derived poliovirus (VDPV2) outbreak. Design, Setting, and Participants This case series was conducted in China after a VDPV2 was detected in stool specimens from a child with acute flaccid paralysis (AFP) in Sichuan Province in 2019, 3 years after the global withdrawal of live, attenuated type 2 oral poliovirus vaccine (OPV). Investigation followed National Health Commission and World Health Organization guidance and included searching hospitals for unreported AFP cases; testing stool specimens from the child, his contacts, and local children; enhanced environmental surveillance for VDPV2s in wastewater; and measuring vaccination coverage. Sabin-strain IPV campaigns were conducted in a wide geographic area. Main Outcomes and Measures Any VDPV2 detection after completion of the supplementary immunization activities. Results A 28-nucleotide-change VDPV2 was isolated from a young boy. Three VDPV2s were detected in healthy children; 2 were contacts of the original child, and none had paralysis. A search of 31 million hospital records found 10 unreported AFP cases; none were polio. No type 2 polioviruses were found in wastewater. Prior to the event, polio vaccine coverage was 65% among children younger than 5 years. Sabin-strain IPV campaigns reached more than 97% of targeted children, administering 1.4 million doses. No transmission source was identified. More than 1 year of enhanced poliovirus environmental and AFP surveillance detected no additional VDPVs. Conclusions and Relevance These findings suggest that the circulating VPDV2 outbreak in 2019 was associated with low vaccine coverage. An investigation discovered 3 infected but otherwise healthy children and no evidence of the virus in wastewater. Following Sabin-strain IPV–only campaigns expanding from county to prefecture, the poliovirus was not detected, and the outbreak response was considered by an expert panel and the World Health Organization to have been successful. This success suggests that the Sabin-strain IPV may be a useful tool for responding to circulating VDPV2 outbreaks when high-quality supplementary immunization activities can be conducted and carefully monitored in settings with good sanitation.

目的 了解安阳市健康人群流行性脑脊髓膜炎(简称流脑)抗体水平,初步评价人群中流脑免疫状况,为完善相应的防控措施提供依据.方法 采取多阶段分层抽样方法,对2019年8至10月安阳市7个年龄组的健康人群进行现场调查、采样,用酶联免疫吸附试验检测血清中A群、C群流脑抗体水平.结果 安阳市健康人群中A群流脑抗体阳性率27.88％,抗体浓度中位数为1.42 mg/L,C群流脑抗体阳性率85.45％,抗体浓度中位数为5.48 mg/L.在2岁及以下儿童中A群、C群抗体水平均为最低,而在20岁以上人群均为最高;女性A群、C群流脑抗体水平均高于男性(P＜0.05);20岁以下人群中,有C群流脑疫苗接种史的人群抗体水平高于无接种史(或接种史不详)人群(P＜0.05),而有、无A群流脑疫苗接种史人群中抗体水平差异无统计学意义(P＞0.05).结论 安阳市部分人群尤其是低年龄人群流脑抗体水平不高,需做好流脑疫苗基础免疫和加强免疫工作,以提高人群免疫力.

目的 了解北京市丰台区幼儿园儿童视屏时间现况及视屏时间过长的影响因素,为制定视屏时间过长相关防控措施提供参考依据.方法 采用方便抽样,利用自制问卷对北京市丰台区9所幼儿园儿童的教师和家长进行调查.调查内容包括幼儿园儿童及家长的社会人口学特征,儿童每日视屏时间(在家和在校),儿童视屏时间可能影响因素.本次调查中将视屏时间＞1 h/d的儿童定义为超标组,视屏时间≤1h/d小时的儿童定义为合格组.通过统计描述、卡方检验和多因素logistic分析,了解儿童的视屏时间现况并分析其与可能影响因素之间的关系,显著性水平为0.05.结果 北京市丰台区1014名幼儿园儿童中,男童504名,年龄中位数为4岁.儿童每天视屏时间中位数为60 min,视屏时间超标儿童比例为46.7％(474/1 014).Logistic回归分析表明,导致儿童视屏时间＞1 h/d的因素包括:儿童年龄增高(≥5岁年龄组OR = 1.85,95％CI:1.27～2.70,P ＜ 0.01)、看护人为男性(OR = 1.65,95％CI:1.13～2.40,P ＜0.05)、看护人文化程度低于本科水平(大专学历水平OR = 2.33,95％CI:1.42～3.83,P＜0.01;高中学历水平OR =2.34,95％Cl:1.45～3.78,P＜0.01;初中及以下学历水平OR =2.00,95％CI:1.20～3.33,P ＜0.01).结论 北京市丰台区幼儿园儿童视屏时间超标的比例较高.儿童年龄越大、看护人为男性、看护人文化程度低等因素是导致幼儿园儿童视屏时间增加的危险因素.应针对这些影响因素,结合实际开展减少幼儿园儿童视屏时间的教育和干预工作.

目的 分析2014-2018年安阳市23价肺炎球菌多糖疫苗(PPV23)的接种情况,为制定疫苗使用指导意见提供数据支持.方法 收集2014-2018年安阳市免疫规划信息管理系统(以下简称信息系统)中所有管理儿童PPV23接种数,同时收集2018年各预防接种门诊逐级统计上报的信息系统中未包含人群的PPV23接种数.采用描述流行病学方法对2018年各年龄组PPV23的接种率、2014-2018年2～14岁人群PPV23接种情况及各县(市、区)2～3岁组接种情况等进行分析.结果 2018年安阳市2岁组人群接种率为6.91％,≥60人群接种率为0.01％.2014-2018年安阳市2～14岁人群PPV23共接种26 177人份,其中2岁组、3岁组接种数分别占49.15％和27.25％.结论 安阳市PPV23主要接种人群是2～3岁儿童,60岁及以上人群接种率极低.应进一步规范基层PPV23的接种服务,开展有针对性的疫苗接种指导相关培训.

目的 了解北京市丰台区3～6岁学龄前儿童的夜间睡眠时间及其影响因素,为开展学龄前儿童睡眠时间健康教育与干预提供参考.方法 于2019年4月采用方便抽样方法选取丰台区5个街道9所幼儿园的1004名3～6岁学龄前儿童作为研究对象,利用问卷星平台采用自制的结构式问卷对主要看护儿童的家长进行线上调查,了解儿童基本情况、儿童夜间睡眠时间、每日户外活动时长、每日视屏时间、每周兴趣班学习时长、家庭人均月收入、家庭类型以及主要看护家长基本情况.采用SPSS 22.0统计软件进行方差分析、x2检验、趋势x2检验和多因素logistic回归分析.结果 实际完成调查996人,应答率为99.2％.3～6岁学龄前儿童平均每日夜间睡眠时间为(9.2±1.0)h,男孩和女孩分别为(9.2±1.0)和(9.3±1.0)h,差异无统计学意义(P＞0.05).每日夜间睡眠时间达到10h的儿童比例为36.7％,其中男童为34.7％,女童为38.8％,差异无统计学意义(P＞0.05).3～、4～、5～和6～岁组儿童平均每日夜间睡眠时间依次为(9.6±1.1)、(9.3±1.0)、(9.2±0.9)和(8.9±0.9)h,每日夜间睡眠时间随年龄增长呈下降趋势(P＜0.05).3～6岁学龄前儿童每日夜间睡眠时间达到10h的比例由3～岁组的50.3％(74/147)降至6～岁组的23.6％(35/148),随年龄增长呈下降趋势(P＜0.05).多因素logistic回归分析结果显示,学龄前儿童发生夜间睡眠时间不足10h的风险随年龄增长而升高(OR=1.371,95％CI:1.170～1.607,P＜0.05);与男性看护家长相比,女性家长看护的儿童发生夜间睡眠时间不足10h的风险较低(OR=0.583,95％CI:0.377～0.901,P＜0.05).结论 丰台区3～6岁学龄前儿童夜间睡眠时间不足情况较为普遍,儿童年龄、看护人性别是影响儿童睡眠时间的主要因素.

目的 了解安阳市儿童家长预防接种知识、态度、行为现状,探讨影响因素.方法 采用多阶段抽样方法,对2011-2016年出生的儿童家长进行问卷调查,并对数据进行统计分析.结果 共收回227份有效问卷,儿童家长预防接种知识知晓率62.6％,态度和行为平均得分为8.儿童家长文化程度越高,预防接种知识知晓率越高(OR=1.495,95％CI:1.065～2.097),态度和行为积极性亦越高(OR=1.605,95％CI:1.187～2.170).结论 安阳市儿童家长预防接种知识知晓率偏低,态度和行为积极性较高,儿童家长的文化程度是主要影响因素.提示应开展多种形式的宣传教育,提升儿童家长预防接种知识水平,以进一步提高其对预防接种的主动参与性.

What is already known about this topic? After the type 2 strain of the live, attenuated poliovirus vaccine was withdrawn globally in 2016, any identification of a type 2 poliovirus is a Public Health Emergency of International Concern. A vaccine-derived type 2 poliovirus (VDPV2) was identified in Sichuan, prompting an urgent, comprehensive investigation and response. What is added by this report? Type 2 monovalent, live, attenuated oral poliovirus vaccine (mOPV2) is being used to respond to the numerous VDPV2 outbreaks seen around the world. In contrast, the response in Sichuan used Sabin strain inactivated poliovirus (sIPV) to stop circulation of the VDPV2. In the 6 months following the vaccination response, there have been no VDPV2s detected in Sichuan, despite extensive search. What are the implications for public health practices? Further search for the VDPV2 must continue in order to determine whether transmission has been stopped. The ongoing investigation and response to the Sichuan VDPV2 is providing evidence to the Global Polio Eradication Initiative on managing VDPV2 outbreaks.

目的 分析2015-2017年安阳市第二类疫苗疑似预防接种异常反应(AEFI)发生情况,评价安阳市第二类疫苗预防接种安全性.方法 通过“预防接种管理”和“AEFI监测管理”系统分别导出2015-2017年安阳市第二类疫苗接种数据及AEFI监测情况,采用描述性流行病学方法对第二类疫苗AEFI发生特征进行分析.结果 2015-2017年安阳市累计接种第二类疫苗487 724剂次,报告第二类疫苗AEFI病例287例,报告发生率58.84/10万剂次,其中异常反应13例,报告发生率2.67/10万剂次;报告发生率居前五的疫苗包括流脑A+C结合疫苗(380.88/10万剂次)、DTap-Hib四联疫苗(299.10/10万)、23价肺炎疫苗(240.43/10万剂次)、DTaP-IPV和-Hib五联疫苗(211.14/10万剂次)、轮状病毒疫苗(123.48/10万剂次).结论 安阳市第二类疫苗预防接种安全性较好,但需加强第二类疫苗AEFI监测报告工作,提高监测敏感性和工作质量.

BackgroundThe initial cases of novel coronavirus (2019-nCoV)-infected pneumonia (NCIP) occurred in Wuhan, Hubei Province, China, in December 2019 and January 2020. We analyzed data on the first 425 confirmed cases in Wuhan to determine the epidemiologic characteristics of NCIP. MethodsWe collected information on demographic characteristics, exposure history, and illness timelines of laboratory-confirmed cases of NCIP that had been reported by January 22, 2020. We described characteristics of the cases and estimated the key epidemiologic time-delay distributions. In the early period of exponential growth, we estimated the epidemic doubling time and the basic reproductive number. ResultsAmong the first 425 patients with confirmed NCIP, the median age was 59 years and 56% were male. The majority of cases (55%) with onset before January 1, 2020, were linked to the Huanan Seafood Wholesale Market, as compared with 8.6% of the subsequent cases. The mean incubation period was 5.2 days (95% confidence interval [CI], 4.1 to 7.0), with the 95th percentile of the distribution at 12.5 days. In its early stages, the epidemic doubled in size every 7.4 days. With a mean serial interval of 7.5 days (95% CI, 5.3 to 19), the basic reproductive number was estimated to be 2.2 (95% CI, 1.4 to 3.9). ConclusionsOn the basis of this information, there is evidence that human-to-human transmission has occurred among close contacts since the middle of December 2019. Considerable efforts to reduce transmission will be required to control outbreaks if similar dynamics apply elsewhere. Measures to prevent or reduce transmission should be implemented in populations at risk. (Funded by the Ministry of Science and Technology of China and others.) The authors provide an epidemiologic analysis of the first 425 confirmed cases of infection with the novel coronavirus in Wuhan, China. This analysis provides estimates of the epidemic doubling time and the basic reproductive number and shows clear evidence of sustained human-to-human transmission.

Objective The aim of this study was to understand the epidemiological characteristics of measles in Anyang from 2014 to 2016,in order to summarize the progress towards measles elimination.Methods Descriptive epidemiological analysis was conducted on the data collected from Measles Surveillance Information Reporting System.Results A total of 164 measles cases were reported during the period from 2014 to 2016,with a average annual incidence rate of 1.37/lakh.The ratio of male to female was 1.02∶1.The highest incidence rate occurred among infants aged less than 5 years old,followed by people aged 20-34 years old.Scattered children and farmers belonged to the group of high incidence.Over 44.51％ of measles cases had no history of vaccination,among which 69.23％ were 8-17 months old cases and 22.58％ were 18-59 months old cases.Trends in the incidence were basically similar during the period.And the total amount of measles cases from February to July was the most,which accounted for 90.85％ of all cases.Higher incidence rotes were reported in Neihuang.In the city,there were 47 towns and offices with ≥ 1 cases reported in 2015.Conclusion In recent years,measles had a comeback trend in Anyang,and eradication of measles remains an arduous task.There was a significant difference in the incidence of measles at different ages.And young children should be the main population with more concern.The key measures to reduce the incidence of measles are to increase the rate of vaccination and strengthen the monitoring of measles.