重庆市2000～2005年流行性脑脊髓膜炎监测结果分析

[目的]分析重庆流行性脑脊髓膜炎的流行特征,了解人群免疫状况,预测发病趋势。[方法]收集重庆市2002～2005年流脑发病疫情报告资料。对2005年的病例及其密切接触者脑脊液、血液进行细菌培养。在2005年按东南西北中随机抽取5个区县作为流脑健康人群监测点,分9个年龄组人群,采集咽拭子及静脉血进行带菌调查及抗体水平检测。[结果]2000～2005年全市报告病例719例,病死率为3.34%,年发病率在0.26～0.57/10万之间波动。2～4月为发病高峰(占57.02%),年龄以小于10岁组为主(506例)。病例血清Nm抗体阳性率为31.25%(5/16),密切接触者阳性率为17.12%(19/111),病例和密切接触者流脑A群和C群抗体的阳性率差异均无统计学意义(χ2=0.54、1.11,P﹥0.05)。2005年5个监测点A群抗体阳性率为22.6%,GMT为1︰1.70;C群抗体阳性率为13.6%,GMT为1︰1.28,A群和C群抗体均阳性为5.70%。各监测点阳性率差异有统计学意义(χ2=104.6,P﹤0.01)。A群抗体水平与是否接种疫苗有关联性。而C群抗体和两群抗体水平与是否接种A C疫苗接种无关联性。流脑病例样品阳性率为4.44%(2/45),A群和C群为主要流行株,病例密切接触者和健康人群均未检出Nm。[结论]重庆市流脑发病以散发为主,健康人群流脑IgG抗体的阳性率较低,提示大部分人对流脑易感。因此加强流脑监测,提高实验室检测能力和疫苗的有效接种是控制流脑流行的关键。     

广东省2002～2003年流脑监测结果分析

目的 了解广东省流行性脑脊髓膜炎(流脑)流行特征,预测流脑发病趋势,为合理制定有效的预防措施提供依据。方法 收集广东省2002～2003年流脑发病疫情报告资料。选择广州、湛江、韶关及东莞4个市作为流脑重点监测点。每年在流脑流行前期(10～11月)按流脑监测方案采集各市内各年龄组人群的咽拭子及静脉血,分别进行健康人群带茵调查及人群抗体水平检测。结果 2002～2003年全省共报告流脑病例47例,其中本省籍14例,外省籍33例;本省籍14例中以学生为多(6例),年龄以10～14岁组为多(共5例)。2002年4个监测点流脑IgG抗体的总阳性率为76．5％(1118／1461),健康人群脑膜炎奈瑟茵(Nm)的带茵率为1．04％(16／1532)。2003年各监测点健康人群Nm的带茵率为1．56％(23／1474)。健康人群带茵以B群Nm为主。结论 广东省流脑发病以散发为主,健康人群Nm的带菌率很低,流脑IgG抗体的总阳性率维持在较高的水平,提示大部分人对流脑有免疫力。     

广东省2010～2013年健康人群C群脑膜炎奈瑟菌抗体水平分析

目的了解广东省2010~2013年健康人群C群脑膜炎奈瑟菌(Neisseria meningitidis,Nm)抗体水平及变化趋势,为预防控制流行性脑脊髓膜炎(流脑)提供参考。方法按照《全国流脑监测点工作手册(2010年)》要求,并结合广东省实际情况,连续在广州、东莞和韶关市采集健康人群血标本,采用杀菌力试验方法,测定血清中C群Nm抗体。结果 2010~2013年,共采集健康人群血标本3158份。C群Nm抗体阳性率和保护率,分别从2010年的29.83%和27.36%上升到2013年的45.94%和41.61%。健康人群C群Nm抗体阳性率和保护率出生后逐渐降低,3岁前降到最低水平,3岁后明显上升,5~14岁有所降低,15岁以后又缓慢上升。健康人群C群Nm抗体阳性率和保护率从高到低依次为广州、东莞和韶关市。男性的C群Nm抗体阳性率和保护率均高于女性。结论广东省2008年9月将A+C群脑膜炎球菌多糖疫苗纳入国家免疫规划,2010~2013年健康人群C群Nm抗体水平逐年提高,但仍存在年龄、地区和性别差异。     

中国2006年流行性脑脊髓膜炎监测结果分析

目的分析中国(未包括香港、澳门特别行政区和台湾地区,下同)2006年流行性脑脊髓膜炎(流脑)重点监测省及国家级监测点流行病学监测和实验室监测结果,评价流脑监测现状,为预防控制流脑爆发、流行及探索经济有效的预防控制策略提供依据。方法利用重点监测省及监测点上报的资料、中国疾病预防控制中心(CDC)传染病预防控制所国家流脑实验室检测资料及法定传染病报告系统的资料,对2006年监测结果进行分析。结果全国2006年流脑报告发病率<0.2/10万,重点监测省中以安徽省发病数较多(261例);监测重点省<15岁儿童平均发病率为0.45/10万,儿童、学生报告病例数分别占重点监测省报告病例总数的25.35%和41.31%。重点监测省报告病例中检出A群脑膜炎奈瑟菌(Neisseria meningitidis,Nm)占44.83%,C群Nm占41.38%;健康人群中检出A群Nm占17.76%,B群Nm占48.68%,C群Nm占17.11%;健康人群A群Nm抗体阳性率平均为78.36%,C群为58.67%。结论流脑流行菌群仍以A群Nm为主,C群Nm检出增多;健康人群带菌以B群Nm为主,C群Nm抗体阳性率明显低于A群。应针对薄弱环节,继续加强流脑监测,防止流脑爆发、流行。     

重庆市健康人群A群C群脑膜炎奈瑟菌抗体水平调查

目的了解重庆市健康人群A、C群脑膜炎奈瑟菌(Nm)抗体水平,为制定预防控制流行性脑脊髓膜炎(流脑)措施提供依据。方法采用分层随机抽样方法,在5个区、县共采集1 125名健康人群血清标本,应用酶联免疫吸附试验检测A、C群Nm抗体。结果调查的1 125名健康人群中,A群Nm抗体阳性率22.58%(254/1 125),几何平均滴度(GMT)为1∶1.70;C群Nm抗体阳性率11.73%(132/1 125),GMT为1∶1.30。A、C群Nm抗体水平均较低,A群Nm抗体水平相对较高。A群Nm抗体水平与是否接种A群或A C群脑膜炎菌多糖疫苗有关联性,而C群抗体水平与是否接种A C群脑膜炎菌多糖疫苗无关联性。结论及时接种A C群脑膜炎球菌多糖疫苗对预防控制流脑有重要意义,应提高疫苗的有效接种率。     

2009年屏南县部分健康人群流脑带菌情况和免疫水平调查

[目的]了解屏南县流行性脑脊髓膜炎(流脑)带菌状况和免疫抗体水平,预测流脑发病的趋势,为流脑的防控工作提供科学依据。[方法]2009年12月采取分层随机抽样方法采集0~、3~、7~19、≥20岁共4个年龄组健康人群的咽拭子和静脉血,检测脑膜炎奈瑟菌(Nm)IgG抗体。培养采用常规方法,抗体水平测定用ELISA方法。[结果]调查188名健康人群流脑带菌率为零。抗A群Nm抗体阳性率为92.02%,几何平均浓度(GMC)为7.46μg/ml;抗C群抗体阳性率为48.4%,GMC为2.39μg/ml,男女比较抗体浓度和阳性率差异无统计学意义(P>0.05)。不同年龄组A群抗体阳性率差异无统计学意义(P>0.05),C群抗体差异有统计学意义(P<0.05),3~6岁年龄组抗体阳性率最高,0~2岁年龄组最低。A和A+C群流脑疫苗均有接种的A群抗体、C群抗体阳性率均最高,都未接种者阳性率最低,部分无免疫史的人群也检出相应抗体,提示存在Nm自然感染的危险。[结论]屏南县不同年龄组健康人群A群流脑IgG抗体的阳性率维持在较高水平,而C群抗体阳性率较低,应加强流脑疫情监测,普及A+C流脑疫苗的免疫接种,防止流脑的暴发和流行。     

潍坊市健康人群A、C群脑膜炎奈瑟菌抗体水平调查

目的 了解潍坊市健康人群A、C群脑膜炎奈瑟菌(Nm)抗体水平,为制定预防控制流行性脑脊髓膜炎(流脑)措施提供依据.方法 采用分层随机抽样方法 ,在5个县市区共采集1 125名健康人群血清标本,应用酶联免疫吸附试验检测A、C群Nm抗体.结果 调查的1 125名健康人群中,A群Nm抗体阳性率22.58%(254/1 125),几何平均滴度(GMP)为1:1.70;C群Nm抗体阳性率11.73%(132/1 125),GMP为1:1.30.结论 潍坊市健康人群A、C群Nm抗体水平均较低.     

2006年广西流脑监测结果分析

目的了解广西流脑流行特征的动态变化,预测流脑发病趋势,为制定合理防制措施提供依据。方法在2006年全年对广西各市、县进行面上的监测。选择凭祥市、全州县和大化县作为流脑重点监测点在流行前期进行健康人群带菌及抗体水平调查。结果2006年广西流脑发病率为0.094/10万,部分人群的Nm带菌率为1.15%,A群抗体阳性率为29.9%,C群抗体阳性率为21.7%。结论2006年广西流脑发病率不高,病死率较高,监测点人群对A群流脑有一定抵抗力,而对C群流脑的免疫力较低,流脑仍然是广西人民特别是青少年儿童健康的重要威胁。     

江苏省2005年健康人群流行性脑脊髓膜炎监测

目的了解江苏省健康人群流行性脑脊髓膜炎(流脑)A群、C群抗体水平及脑膜炎奈瑟菌(Nm)带菌率,为制定预防控制措施提供依据。方法于苏南、苏北地区各选择1个县(市)作为监测点,采集不同年龄组健康人群血清标本,同时采集苏南地区同一健康人群咽拭子标本,采用酶联免疫吸附试验检测血清流脑A群、C群抗体,咽拭子用于Nm的分离。结果检测流脑A群抗体917人,A群抗体阳性者736人,阳性率为80.26%,GMT为1∶4.05;检测流脑C群抗体932人,C群抗体阳性者536人,阳性率为57.51%,GMT为1∶2.68。A群与C群抗体阳性率、GMT差异均有统计学意义(均P<0.05)。流脑A群抗体阳性率女性为85.04%,高于男性的75.69%(P<0.05);流脑A群抗体GMT、C群抗体阳性率、C群抗体GMT男女性别间差异均无统计学意义。调查健康人群470人,检出脑膜炎奈瑟菌8例,总带菌率为1.70%。8例阳性者中,B群5例,C群3例,带菌率分别为1.06%、0.64%。结论近期内江苏省不会发生流脑A群流行,存在局部暴发流脑C群的可能。应加强流脑监测,大力推广A C群流脑疫苗的接种,逐渐将其纳入计划免疫。     

苏州市1992-2012年流行性脑脊髓膜炎的流行病学特征分析

目的了解苏州市20年来流行性脑脊髓膜炎(简称流脑)的流行病学特征,为有效控制流脑提供科学依据。方法对苏州市1992-2012年流脑疫情、2005-2012年健康人群流脑带菌率和抗体水平调查等资料进行综合流行病学分析。结果苏州市1992-2012年共报告流脑病例164例,年均发病率0.11/10万;流脑发病主要集中在0~29岁年龄(占73.78%);流脑发病高峰为2-4月份(占62.20%);病例中以散居儿童为主(占22.56%);健康人群流脑带菌率为0.64%;健康人群流脑抗体免疫水平:A群抗体阳性率平均为79.16%,C群抗体阳性率平均为54.88%。结论近年来,苏州流脑发病处于低发水平,然而健康人群流脑C群抗体水平普遍较低,健康人群B群流脑的带菌水平较高,应加强B群和C群流脑防治工作。     

中国C群脑膜炎奈瑟菌脉冲场凝胶电泳分析

目的对中国C群脑膜炎奈瑟菌分离株进行脉冲场凝胶电泳（PFGE）分析，了解安徽省C群流行性脑脊髓膜炎（流脑）暴发菌株及国内C群脑膜炎奈瑟菌菌株的分子流行病学特征。方法212株C群脑膜炎奈瑟菌菌株分离自流脑患者、密切接触者和健康人群鼻咽部，包括安徽省C群流脑菌株48株，其中38株与C群流脑暴发相关。脉冲场凝胶电泳选用NheI限制性内切酶，聚类分析选用BioNumerics软件。结果212株C群脑膜炎奈瑟菌菌株共分为43个PFGE带型，命名为AH1～AH43，AH1是中国C群脑膜炎奈瑟菌主要的带型，占69．3％（”=147），分布于11个省市。安徽省48株C群菌株共分为3个PFGE型别（AH1、AH2、AH3），45株（93．8％）为AH1型。安徽省38株与C群流脑暴发相关的菌株中，37株（97．4％）为AH1型。全国53株流脑患者分离菌株中，AH1型菌株占67．9％（36／53）；121株流脑病例密切接触者分离菌株中，AH1型占71．9％（87／121），38株健康人群鼻咽部分离菌株中，AH1型占63．2％（24／38）。结论AH1型C群脑膜炎奈瑟菌是中国目前C群流脑流行的主要克隆群，安徽省C群流脑暴发是由AH1型C群脑膜炎奈瑟菌引起的，已在全国呈扩散流行的趋势。     

Trends in meningococcal disease in Italy 1987

Meningococcal disease in Italy decreased 29% in 1987 from the previous year. The highest number of cases was seen in the 1-4 year-old age group (27%). The frequency in army recruits was 5/100,000, still higher than the 0.57/100,000 in the general population, but less than the 7/100,000 reported in the previous year. Sixty-three percent of the isolates belonged to serogroup C while serogroup B constituted 25%. The proportion of strains resistant to sulphonamides was 52.6%. Six strains were resistant to rifampin and none to minocyclin. No secondary cases occurred. These results are consistent with the trends reported in Italy in 1986. There were two findings of interest in 1987: the absence of secondary cases, attributable to the appropriate administration of chemoprophylaxis; and the decrease in military cases, reflecting the use of bivalent serogroup (A + C) meningococcal polysaccharide vaccine in all new military recruits since January 1987.     

National enhanced surveillance of meningococcal disease in England,Wales and Northern Ireland,January 1999-June 2001

Enhanced surveillance of meningococcal disease (ESMD) was implemented nationally across ten regions of England, Wales and Northern Ireland from 1 January 1999. It aims to deliver more sensitive surveillance than laboratory reporting by including clinically diagnosed but laboratory unconfirmed cases. Consultants in Communicable Disease Control (CsCDC) report all clinically diagnosed cases of meningococcal disease (MD) to the Regional Epidemiologist in the relevant regional unit of the Public Health Laboratory Service (PHLS) Communicable Disease Surveillance Centre (CDSC). These reports are reconciled with laboratory data from the PHLS Meningococcal Reference Unit and then forwarded to the national CDSC where further reconciliation with laboratory data takes place. In addition, CsCDC are asked to report any clusters of MD that occur. Between 1 January 1999 and 30 June 2001, 12,074 cases of MD were ascertained through ESMD. The majority (57%) were laboratory confirmed. The estimated incidence of MD fell between 1999 and 2001 from 9.2 to 8.0 per 100,000 population. Of laboratory confirmed cases, the number of cases of serogroups B and W135 increased and of serogroup C and of ungrouped meningococcal infection decreased. Variation between regions was considerable and deserves further investigation. Of 11,522 cases with a reported clinical diagnosis, 53.6% were diagnosed as septicaemia, 32.6% as meningitis, 12.5% as both septicaemia and meningitis, and 13% had other invasive MD. Between 1 January 1999 and 30 June 2001 698 deaths were reported, an overall case fatality rate (CFR) of 5.8%; 567 deaths were in confirmed cases and 131 probable (CFR 8.2% and 2.5%, respectively). CFR was higher in serogroup C (13.5%) than B (5.8%). No peak in serogroup C meningococcal infection occurred in the winter of 2000/1 and no clusters of serogroup C meningococcal infection were reported in the first half of 2001. ESMD provides information about the epidemiology of MD that is more complete than statutory notification and laboratory surveillance and is useful for evaluating the impact of the meningococcal serogroup C vaccination programme and of the other non-vaccine preventable serogroups.     

Enhanced surveillance scheme for suspected meningococcal disease in five regional health authorities in England: 1998

Enhanced surveillance of meningococcal disease (ESMD) began in five English regions on 1st January 1998. The aims of the scheme were to obtain accurate incidence data and develop a robust surveillance system with which to monitor the impact of a new meningococcal serogroup C conjugate vaccine. During 1998, 2,314 suspected cases of meningococcal disease were identified. The majority (84%) was classified as invasive meningococcal disease, with infection of N. meningitidis confirmed in 66%. Sixteen per cent of suspected cases were subsequently given an alternative diagnosis. Age differences between those classified as meningococcal disease and those not, implied a higher index of suspicion of meningococcal disease in younger children. Regions with high rates of meningococcal disease were due to a higher rate of serogroup C. ESMD increased ascertainment of meningococcal disease and deaths. Cases were 34% greater than identified through statutory notifications, an additional 6.8% confirmed infections were identified than were reported to the PHLS Meningococcal Reference Unit (MRU) and deaths were 24% greater than death registrations. These data were used to inform the national meningococcal serogroup C conjugate vaccination programme in England and Wales. In 1999 ESMD was extended to all regions of England, Wales and Northern Ireland.     

Trends in meningococcal disease in Italy in 1988

Meningococcal disease in Italy decreased 15% in 1988 from the previous year (290 vs. 342 cases). The decline was particularly evident in military cases (1.7/100,000 in 1988 vs. 5/100,000 in 1987) reflecting the full coverage of bivalent serogroup (A + C) meningococcal polysaccaride vaccine in army recruits, achieved since January 1988. The highest proportion of cases was seen in people older than 25 years of age (25%). Serogroup C constituted 60% of the isolates, while 19% belonged to serogroup B. The proportion of strains resistant to sulphonamides was 45%, while 15% were resistant to Minocycline and none to Rifampin. Out of the five military cases, only one (due to serogroup C) was attributable to the vaccine failure. A single coprimary case, but no secondary cases occurred among civilians. These findings are consistent with the trends reported in Italy in the previous years.     

Predicted coverage by 4CMenB vaccine against invasive meningococcal disease cases in the Netherlands

Neisseria meningitidis serogroup B is a major cause of invasive meningococcal disease in Europe. In the absence of a conjugate serogroup B vaccine, a subcapsular 4CMenB vaccine was developed. Data on 4CMenB vaccine efficacy is still limited. Recently, genomic MATS (Meningococcal Antigen Typing System) was developed as a tool to predict strain coverage, using vaccine antigens sequence data. We characterized all invasive meningococcal isolates received by the Netherlands Reference Laboratory for Bacterial Meningitis (NRLBM) in two epidemiological years 2017–2019 using whole-genome sequencing and determined serogroup, clonal complex (cc) and estimated 4CMenB vaccine coverage by gMATS. Of 396 cases of invasive meningococcal disease, corresponding to an incidence of 1.22 cases/10⁵ inhabitants, 180 (45%) were serogroup W, 155 (39%) serogroup B, 46 (12%) serogroup Y, 10 (3%) serogroup C, 2 non-groupable (0.5%) and 3 (0.7%) unknown. The incidence was the highest among 0–4 years olds (4 cases/10⁵ inhabitants), and 57/72 (79%) of these cases were serogroup B. Serogroup W predominated among persons 45 years of age or older with 110/187 (59%) cases. Serogroup B isolates comprised 11 different clonal complexes, with 103/122 (84%) isolates belonging to 4 clonal complexes: cc32, cc41/44, cc269 and cc213. In contrast, serogroup W isolates were genetically similar with 95% belonging to cc11. Of 122 serogroup B isolates, 89 (73%; 95% CI: 64–80%) were estimated to be covered by 4CMenB and the degree of coverage varied largely by clonal complex and age. Among the 0–4 year olds, 25 of 43 (58%; 95% CI: 43–72%) MenB isolates were estimated to be covered. Since the coverage of the 4CMenB vaccine is dependent on circulating clonal complexes, our findings emphasize the need for surveillance of circulating meningococcal strains. In addition, estimation of age specific coverage is relevant to determine the right target age group for vaccination.     

Invasive meningococcal disease and travel

The epidemiology of invasive meningococcal disease varies geographically and in time and the risk of acquiring the disease varies regionally, as well as with living conditions and behavior. An area, in which meningococcal disease outbreaks have frequently occurred, is the "African meningitis belt", where epidemics of meningococcal disease with a peak incidence as high as 100-800/100,000 population/year have been reported. Another risk factor is mass gatherings including the Islamic pilgrimage to Makkah (Mecca), where outbreaks of meningococcal disease have repeatedly occurred. The latest outbreaks occurred during the Hajj pilgrimages of 2000 and 2001, when a shift from serogroup A disease to serogroup W135 occurred. Vaccination against serogroups A, C, W-135 and Y with novel conjugate vaccines may help protect individuals and reduce the spread of bacterial carriage and disease. Individuals who should be vaccinated include travelers to epidemic or hyperendemic areas (as identified by international health authorities), travelers for Umra or Hajj (Hajj pilgrims), travelers to high risk countries or regions (African meningitis belt) during the dry season or countries in sub-Saharan Africa outside the meningitis belt (where outbreak of meningitis has been reported in the preceding 2-3 years), military recruits or deployed military personnel, immunocompromized travelers and high school and college students. This review presents the global epidemiology of meningococcal disease, and discusses prophylaxis options including meningococcal ACWY vaccines.     

Serogroup W-135 meningococcal disease during the Hajj, 2000

An outbreak of serogroup W-135 meningococcal disease occurred during the 2000 Hajj in Saudi Arabia. Disease was reported worldwide in Hajj pilgrims and their close contacts; however, most cases were identified in Saudi Arabia. Trends in Saudi meningococcal disease were evaluated and the epidemiology of Saudi cases from this outbreak described. Saudi national meningococcal disease incidence data for 1990 to 2000 were reviewed; cases from January 24 to June 5, 2000, were retrospectively reviewed. The 2000 Hajj outbreak consisted of distinct serogroup A and serogroup W-135 outbreaks. Of 253 identified cases in Saudi Arabia, 161 (64%) had serogroup identification; serogroups W-135 and A caused 93 (37%) and 60 (24%) cases with attack rates of 9 and 6 cases per 100,000 population, respectively. The 2000 Hajj outbreak was the first large serogroup W-135 meningococcal disease outbreak identified worldwide. Enhanced surveillance for serogroup W-135, especially in Africa, is essential to control this emerging epidemic disease.     

The changing and dynamic epidemiology of meningococcal disease

The epidemiology of invasive meningococcal disease continues to change rapidly, even in the three years since the first Meningococcal Exchange Meeting in 2008. Control of disease caused by serogroup C has been achieved in countries that have implemented meningococcal C or quadrivalent meningococcal ACWY conjugate vaccines. Initiation of mass immunization programs with meningococcal A conjugate vaccines across the meningitis belt of Africa may lead to the interruption of cyclical meningococcal epidemics. A meningococcal B vaccination program in New Zealand has led to a decreased incidence of high rates of endemic serogroup B disease. Increases in serogroup Y disease have been observed in certain Nordic countries which, if they persist, may require consideration of use of a multiple serogroup vaccine. The imminent availability of recombinant broadly protective serogroup B vaccines may provide the tools for further control of invasive meningococcal disease in areas where serogroup B disease predominates. Continued surveillance of meningococcal disease is essential; ongoing global efforts to improve the completeness of reporting are required.     

广州市萝岗区C群流行性脑脊髓膜炎抗体水平调查分析

目的 了解广州市萝岗区C群流行性脑脊髓膜炎抗体水平。 方法 2013年采取分层随机抽样的方法采集萝岗区8个不同龄组健康人群血清学进行抗体检测。 结果 萝岗区C群流行性脑脊髓膜炎血清杀菌抗体阳性率为60.30%(161/267),保护率为55.43%(148/267)。7~14岁最高,抗体阳性率和保护率高达94.59%和89.19%,其次是3~6岁,抗体阳性率和保护率均为75.32%,3岁以下儿童抗体阳性率和保护率最低,仅有26.23%和22.95%。 结论 萝岗区C群流行性脑脊髓膜炎抗体水平仍达不到防控要求;3岁以下散居儿童是C群流行性脑脊髓膜炎防控的重点人群。