利用CUSUM和EWMA模型法探测流感流行起始预警

目的探讨CUSUM模型(累积和)和EWMA模型(指数加权移动平均)探测流感流行起始的功效。方法利用北京市顺义区2013年9月1日-2015年4月30日流感样病例监测数据,调整不同参数采用CUSUM和EWMA模型对监测数据进行分析,与流感病原学结果进行比较,分析二种模型在不同参数组合下探测流感流行起始的效果。结果流感样病例监测显示,CUSUM模型当k=0.9和H=2σ时,根据金标准算探测结果恰好是最早流行起始时间,而EWMA模型探测流感流行起始时间当λ=0.7、k=3时与金标准最为接近。结论顺义区利用流感样病例监测结果,CUSUM模型和EWMA模型,均能及时准确地预警流感高峰的到来,但是仍然需要继续对模型参数进行拟合和分析。     

预警机制对麻疹防控的效果研究

[目的]探索预警机制在麻疹防控中的作用。[方法]收集攀枝花市2007年麻疹流行期间的防控资料,应用描述流行病学方法进行分析。[结果]通过实施麻疹预警和一系列防控措施,麻疹流行强度持续、迅速下降,也未因传统高发人群的聚集而引起暴发。[结论]在各种导致麻疹免疫空白人群存在的因素尚不能在短期内有效解决的情况下,建立起一套由政府部门牵头的、敏感、有效的预警机制,能有效控制麻疹流行,并避免暴发疫情的出现。但如何提高这一机制启动程序的时间敏感性和判断准确性尚待探讨。     

移动平均模型预警传染病的建立与应用研究

目的探索新的传染病预警模型,评价预警效果。方法联合运用移动平均和线性回归模型,使用株洲市2004-2009年流行性腮腺炎发病数据,建立以周为时间序列的发病模型,计算预警阈值,制作预警控制图,并用灵敏度、特异度、及时性评价预警效果。结果该模型全部预警到株洲市2010-2011年流行性腮腺炎的暴发和流行,灵敏度100%、特异度91.67%,较监测系统早2~6周预警暴发和流行,预警阈值范围在均数加1.6~2.3倍标准差之间。结论联合移动平均和线性回归模型,具有较高的预警灵敏度、特异度和及时性,适合预警有周期性和季节性的常见传染病。     

麻疹疫情自动预警系统的预警效能评估

[目的]评价在不同预警参数下,麻疹疫情自动预警系统的有效性;评价麻疹疫情自动预警系统的预警及时性情况;浅析系统实用性。[方法]以灵敏度、特异度等指标评价麻疹疫情自动预警系统的有效性;以预警信号数据信息的时间点间隔中位数评价麻疹疫情自动预警系统的及时性;对疾控中心人员就使用该系统的问题进行访谈,对系统实用性作定性评估。[结果]在所评价的时间段内,33个试点县(区)自动预警系统共发出麻疹预警信息2025次,试点地区对其中1条预警信号未作出响应;作了初步判断的2024条预警信息中,有2.87%信号与麻疹疑似流行有关;对预警信息的时间间隔分析表明,首例病人发病时间与预警时间的间隔为12d,预警时间与填报时间、现场调查完成时间的间隔均为0d;疑似病例48h完整调查率为89.7%;在P60、P70、P80和P90警戒限,麻疹的预警灵敏度均为100%,特异度大多在30%～70%之间。[结论]建立在病例实时直报的传染病监测系统基础上的传染病自动预警系统的及时性良好,试点地区麻疹预警的敏感性很高,特异度相对较低。根据目前的试点地区的效能分析结果,P90可能是较为合适的预警阈值。     

前瞻性时空重排扫描统计量法在深圳市流行性腮腺炎聚集性疫情早期预警中的应用

目的 分析前瞻性时空重排扫描统计量法应用于深圳市流行性腮腺炎疫情早期预警的效果,为传染病监测预警系统的完善提供科学依据。 方法 以深圳市为研究范围,以街道行政区域为研究尺度,使用SaTScan软件前瞻性时空重排扫描模型对深圳市2012年1月1日—12月31日流行性腮腺炎发病情况进行逐日模拟预警。根据国家疾病监测信息报告管理系统 (大疫情系统)上报的病例个案信息、深圳市疾病控制信息管理系统(深圳系统)上报的聚集性疫情事件,核实模拟预警信息的真实性,计算模型的灵敏度、错误预警率、暴发探测时间、预警提前时间等指标。比较时空重排扫描模型和国家传染病自动预警系统(China Infectious Disease Automated-alert and Response System,CIDARS)时间序列模型、时空序列模型预警效果的差异。 结果 深圳系统2012年共上报29宗流行性腮腺炎聚集性事件,共计纳入深圳市2011年12月3日—2012年12月31日的流行性腮腺炎分析病例9 756例,累计分析366次,其中P≤0.05的预警信号数为88条,被确认为阳性信号的有16次,模型的灵敏度为55.17%(16/29),错误预警率为81.82%(72/88)。暴发探测时间在0~22 d之间,平均6.25 d,中位数为4 d。预警提前时间在-12~41 d之间,平均9.75 d,中位数为5.5 d。CIDARS中2012年深圳市流行性腮腺炎时间序列预警信号发出319次,被判断阳性的2次,灵敏度为6.90%(2/29),错误预警率为99.37%(315/317),时空序列预警信号发出208次,被判断阳性3次,灵敏度为10.34%(3/29),错误预警率为98.56%(205/208)。时空重排扫描模型信号数比大疫情系统时间序列模型和时空序列模型预警分别下降72.41%和57.69%。时空重排扫描模型灵敏度显著高于大疫情系统中时间序列模型(P<0.001)和时空序列模型(P<0.001)。时空重排扫描模型的错误预警率显著低于CIDARS时间序列(P<0.001)和时空序列模型的错误预警率(P<0.001)。 结论 前瞻性时空重排扫描模型在深圳市流行性腮腺炎疫情中具有较好的早期预警效果。     

传染病预警模型研究进展

<正>2003年传染性非典型肺炎(SARS)和2009年甲型H1N1流感的全球暴发表明传染病依然是生命健康和社会经济的重大威胁。经济全球化、生产国际化、交通更加便捷、人货流动加快等因素的影响,使得传染病的传播速度加快、传播范围更广,也加大了传染病的防控难度。及早探测到传染病的早期暴发并发出预警和采取应对措施,对防止传染     

银川市麻疹暴发流行的灰色系统模型预测

文应用灰色系统模型对银川市麻疹暴发流行的时间进行了预测.所建立的预测模型为Ŷ(R)=2871650.2441(R-1)-26.7165,预测效果良好,预测到我市近期两次麻疹可能发生流行的时间分别是2008年和2020年.提示要及早制定防治计划,及早采取有效控制措施.将麻疹监测工作纳入AFP监测系统同时运行.     

接收者工作特征曲线对云南省麻疹预警的探讨

目的探讨传染病预警方法和预警界值及提高传染病疫情监测的预警能力。方法使用云南省疾病预防控制中心5年的麻疹报告数据建立预警数据库,采用控制图法建立预警模型,通过计算、比较灵敏度、特异度、阳性预测值和绘制接收者工作特征曲线,并比较曲线下面积,优选出合适的预警界值。结果云南省麻疹选用P80作为预警界值预警效果较好,灵敏度和特异度均在90%以上。结论绘制接收者工作特征曲线是评价筛查试验直观而有效的方法,可在传染病预警技术中推广应用。     

基于百度指数的诺如病毒感染暴发疫情预警研究

目的 探讨百度搜索指数与诺如病毒感染暴发疫情的关联性,用百度指数对暴发疫情进行预警.方法 收集浙江省2018年12月 2020年12月诺如病毒感染暴发疫情和百度指数数据,通过小波分析方法解析二者数据的周期性及关联性,通过随机森林方法探索预警阈值.结果 浙江省百度搜索指数和诺如病毒感染暴发疫情呈现相似的季节性特征,均在年...     

发热呼吸道症状监测在甲型H1N1流感暴发早期预警的效果

目的探讨发热呼吸道症状监测在甲型H1N1流感暴发早期预警效果。方法收集2007年1月-2009年12月本地区发热呼吸道症状监测数据进行分析,对2009年甲型H1N1流感暴发疫情数据进行拟合判断预警效果。结果 2009年甲型H1N1病例数在第35周后明显增加,在42周到达高峰,随即开始下降,其走势与ILI%(流感样病例占同期门急诊就诊总人数百分比)趋势相同;控制图法预警显示:ILI%在21~29周,35~43周和46周出现预警信息,基本与2009年甲型H1N1流行趋势一致;移动平均数回归法预警显示,2009年25~26周,29周,36~42周ILI%超过平均线,其中第42周超过了平均线+2.0标准差预警线,与2009年甲型H1N1第42周达到高峰的流行趋势吻合。结论发热呼吸道症状监测预警能较好的反映甲型H1N1流感暴发疫情,其中应用移动平均回归法预警效果较控制图法好。     

北京市朝阳区一起麻疹暴发疫情调查

对2007年3月17日至6月21日北京市朝阳区麻疹暴发疫情进行调查分析. 1.资料与方法:病例资料来源于法定传染病网络报告系统,流行病学资料经专业人员个案调查所得,采用描述性流行病学进行分析,应用Excel和SPSS 13.0软件进行数据统计分析.     

Cost of a measles outbreak in a remote island economy: 2014 Federated States of Micronesia measles outbreak

After 20 years with no reported measles cases, on May 15, 2014 the Centers for Disease Control and Prevention (CDC) was notified of two cases testing positive for measles-specific immunoglobulin M (IgM) antibodies in the Federated States of Micronesia (FSM). Under the Compact of Free Association, FSM receives immunization funding and technical support from the United States (US) domestic vaccination program managed by the Centers for Disease Control and Prevention (CDC). In a collaborative effort, public health officials and volunteers from FSM and the US government worked to respond and contain the measles outbreak through an emergency mass vaccination campaign, contact tracing, and other outbreak investigation activities. Contributions were also made by United Nations Children’s Emergency Fund (UNICEF) and World Health Organization (WHO). Total costs incurred as a result of the outbreak were nearly $4,000,000; approximately $10,000 per case. Direct medical costs (≈$141,000) were incurred in the treatment of those individuals infected, as well as lost productivity of the infected and informal caregivers (≈$250,000) and costs to contain the outbreak (≈$3.5 million). We assessed the economic burden of the 2014 measles outbreak to FSM, as well as the economic responsibilities of the US. Although the US paid the majority of total costs of the outbreak (≈67%), examining each country’s costs relative to their respective economy illustrates a far greater burden to FSM. We demonstrate that while FSM was heavily assisted by the US in responding to the 2014 Measles Outbreak, the outbreak significantly impacted their economy. FSM’s economic burden from the outbreak is approximately equivalent to their entire 2016 Fiscal Year budget dedicated to education.     

A new statistical early outbreak detection method for biosurveillance and performance comparisons

Biosurveillance for rapid detection of epidemics of diseases is a challenging area of endeavor in many respects. Hence, this area is in need of development of methodology and opens to novel methods of detection. In this study, a new simple statistical early outbreak detection approach is proposed to detect outbreaks of diseases in real time. The new approach is called LWMAT since it is based on linearly weighted moving average. Furthermore, it does not require a long baseline and partly takes into account of likely features of biosurveillance data such as nonstationary and overdispersion to some extent. Moreover, this newly proposed method is easily adapted to automated use in public health surveillance systems to monitor simultaneously large number time series of indicators associated with the relevant diseases. To compare the performance of the new method with those of some well-known outbreak detection methods, semisynthetic data with outbreaks of various magnitudes and durations are simulated by considering the weekly number of outpatient visits for influenza-like illness for the influenza seasons 2014-2015 through 2017-2018 at Centers for Disease Control and Prevention (CDC) in the United States. Under the conditions of the simulation studies, Serfling regression and Farrington flexible seem to be preferable methods for monitoring the weekly influenza data at CDC in terms of early identification of influenza outbreaks with a high probability. In addition, the newly proposed LWMAT-type methods appear to be promising and useful methods in the case of small magnitude outbreaks with a short duration.     

An expensive adult measles outbreak and response in office buildings during the era of accelerated measles elimination,Beijing, China

BackgroundFew measles outbreaks among adults are reported in China, and outbreak response costs are seldom documented. We report an adult measles outbreak and response in 4 linked office buildings in Beijing and its associated costs.MethodThe World Health Organization measles case definitions were used to determine suspected and confirmed measles cases. Surveillance data were used to describe the outbreak, and records and interviews of response staff were used to describe the response. Costs were determined by use of retrospective surveys of cases, review of records, and interviews of staff.ResultsThe outbreak lasted 19 days, and involved 22 cases aged 23–49 years. Nineteen cases had a local household registration. All cases were employed by 8 companies in 4 linked office buildings. Among the 22 cases, 8 had temperature less than 38.5 degree, 18 had no Koplik spots and none had complications or hospitalizations. A total of 7930 contacts were identified, and of these, 6869 were employees in the office buildings. All the child contacts aged 8 months–14 years had been up-to-date for measles-containing vaccine (MCV); no adult could document their vaccination or measles history. Of contacts, about 96% were offered post-exposure vaccination. The total household costs were $13,298, or $605 per case. Control costs were $384,594, or $17,481 per case. Involved companies paid for 90.7% of control costs.ConclusionOffice buildings provide a mechanism for measles transmission. Timely control activities were challenged by the highly infectious nature of measles and mild presentations of cases. The outbreak response was very costly. Financial support by involved companies can provide needed resources for outbreak management.     

宁波市江东区流动人口与本地人口麻疹免疫水平及其影响因素的比较研究

为了解宁波市江东区健康人群麻疹免疫状况,开展了辖区内40岁以下健康流动人口和本地人口麻疹免疫水平调查.     

Evaluation of economic costs of a measles outbreak and outbreak response activities in Keffa Zone,Ethiopia

Objective

To estimate the economic impact of a measles outbreak and response activities that occurred in Keffa Zone, Ethiopia with 5257 reported cases during October 1, 2011–April 8, 2012, using the health sector and household perspectives.

Methods

We collected cost input data through interviews and record reviews with government and partner agency staff and through a survey of 100 measles cases-patients and their caretakers. We used cost input data to estimate the financial and opportunity costs of the following outbreak and response activities: investigation, treatment, case management, active surveillance, immunization campaigns, and immunization system strengthening.

Findings

The economic cost of the outbreak and response was 758,869 United States dollars (US$), including the opportunity cost of US$327,545 (US$62.31/case) and financial cost of US$431,324 (US$82.05/case). Health sector costs, including the immunization campaign (US$72.29/case), accounted for 80% of the economic cost. Household economic cost was US$29.18/case, equal to 6% of the household median annual income. 92% of financial costs were covered by partner agencies.

Conclusion

The economic cost of the measles outbreak was substantial when compared to household income and health sector expenditures. Improvement in two-dose measles vaccination coverage above 95% would both reduce measles incidence and save considerable outbreak-associated costs to both the health sector and households.     

酶联免疫吸附试验与中和抗体试验检测麻疹抗体比较研究

目的探讨酶联免疫吸附试验(ELISA)和中和抗体试验(NT)在麻疹抗体检测中的应用价值。方法以NT为"金标准",同时用德国Virion/Serion的定量ELISA试剂盒检测364份麻疹抗体滴度,将两种方法测定的结果进行比较。结果 NT的阳性率为57.69%,几何平均滴度(GMT)为1∶5.48,ELISA的阳性率为42.86%,平均抗体活性值为48.57IU/L。定性结果发现,ELISA特异度为99.35%,其敏感度即阳性符合率为73.81%,且阳性符合率随着滴度增加呈现增高的趋势(z=-5.99,P<0.001)。Fisher精确概率法发现,滴度1∶2组、滴度1∶4组与其他各组阳性符合率差异均有统计学意义(P<0.05),滴度1∶8组与滴度≥1∶64组阳性符合率差异有统计学意义(P<0.05),其余各组间阳性符合率差异均无统计学意义(P>0.05)。定量结果发现,ELISA抗体活性值与NT滴度呈明显正相关,相关系数r=0.884,P<0.001。结论德国Virion/Serion的定量ELISA试剂盒在检测低滴度麻疹抗体时易出现假阴性,检测高滴度麻疹抗体时,两种方法敏感性接近;滴度临界值为1∶8～1∶16。该试剂可推荐用于健康人群麻疹抗体水平监测。     

2010 - 2019年新乡市麻疹、风疹疑似病例IgM抗体检测结果分析

目的 分析新乡市2010 - 2019年麻疹、风疹疑似病例IgM抗体检测情况,掌握其流行情况,进而科学防控麻疹、风疹。方法 采用酶联免疫吸附试验（ELISA）对新乡市2010 - 2019年麻疹、风疹疑似病例的血清标本进行IgM抗体检测,对结果进行统计分析。结果 2010 - 2019年共检测1 272例麻疹、风疹疑似病例血清,麻疹、风疹IgM抗体阳性数分别为454例和20例,阳性率为35.69%和1.57%。麻疹发病时间高峰在每年3 - 6月。发病4～28天血清中麻疹IgM阳性率高于发病0～3天。麻疹IgM抗体阳性率的性别分布差异无统计学意义（χ2 = 0.035,P = 0.851）。麻疹IgM抗体阳性年龄组主要分布在0～8月、8月～3岁和18～40岁,占比分别为31.94%、28.19%和21.37%,且年龄组间差异有统计学意义（χ2 = 58.378,P = 0.000）。不同人群中麻疹阳性率较高分布在家政家务人员、职员和农民中,分别为60.87%、57.14%、41.63%,差异有统计学意义（χ2 = 46.907,P = 0.000）。有免疫史、无免疫史和免疫史不详这三组人群中麻疹IgM抗体阳性率分别为19.44%、52.17%和31.48%,三组间阳性率差异有统计学意义（χ2 = 124.956,P = 0.000）。麻疹阳性病例地域分布主要集中于辉县和辖区外,分别为168例和116例,分别占37.00%和25.55%。结论 需加强免疫基础薄弱的地区免疫工作,特别是适龄儿童及时接种疫苗,加强辖区交界流动人员管理,对暴露风险大的年龄组采取针对措施。     

北京市通州区麻疹疫苗强化免疫前后麻疹流行病学特征

目的分析北京市通州区强化免疫前后2年麻疹的发病趋势及流行病学特征,评价强化免疫活动的效果,为制定麻疹防控措施提供科学依据。方法采用描述性流行病学方法分析通州区2010年10月麻疹疫苗强化免疫前后的麻疹发病情况。结果通州区2009、2010、2011和2012年麻疹发病数分别为77例、157例、9例和3例;2011~2012年麻疹平均发病率为0.43/10万,比2009~2010年下降了95.34%;麻疹发病仍有明显季节性,发病主要集中在3~5月份;地区分布以流动人口聚集地为主,强化免疫后各地区发病率下降均达到了88.02%以上;麻疹发病多为流动人口,主要由8月龄儿童病例和15岁的成人病例组成,强化免疫后,麻疹发病年龄双向移位现象更为明显。结论通州区麻疹疫苗强化免疫短期效果显著,麻疹疫苗强化免疫可以降低人群易感性,达到快速控制麻疹发病,降低麻疹发病率;根据强化免疫后麻疹流行特征的变化,成人、麻疹常规免疫前儿童和流动人口成为防控麻疹工作的重点和难点。