Molecular epidemiology of rubella viruses involved in congenital rubella infections in São Paulo,Brazil, between 1996 and 2009

Rubella virus (RV) infection during the early stages of pregnancy can lead to serious birth defects, known as congenital rubella syndrome (CRS). This retrospective study was conducted between 1996 and 2009 with surveillance specimens collected from patients suspected of congenital rubella infection (CRI) and CRS. The clinical samples (nine amminiotic fluid, eight urine, eight blood, one conception product, and one placenta) were sent for viral isolation and genotyping. Twenty‐seven sequences were analysed and four genotypes (1a, 1B, 1G, and 2B) were identified in São Paulo that were involved in congenital infection. To our knowledge, this study is the first report that describes genetic diversity of the circulating rubella strains involved in CRI. J Med. Virol. 85:2034–2041, 2013. © 2013 Wiley Periodicals, Inc.

     

Isolation and genotyping of rubella virus from a case of congenital infection in Brazil

The incidence of CRS and CRI has decreased markedly worldwide with the implementation of efficient vaccination programs. We report a congenital rubella case with fetal death occurred at 29th week of gestation. RV was confirmed in placenta. The results of phylogenetic analysis showed that the RVs/SaoPaulo01.- BRA/08.CRI belongs to the genotype 2B of RV.     

深圳市福田区2008-2009年风疹流行特征分析

目的了解深圳市福田区2008-2009年风疹发病情况及流行特征,为今后制定防治措施提供科学依据。方法采用描述性流行病学方法对全区2008-2009年的风疹疫情资料进行分析。结果福田区2008-2009年累计报告风疹病例45例,无死亡病例,年平均报告发病率为1.88/10万,2008年发病率稍高,不同年份间报告的发病率差异无统计学意义（P〉0.05）;各年全区各街道均有发病,2008年风疹高峰期出现在3月份,2009年风疹高发月为5月份;病例高发年龄段在15～35岁;发病群体主要为学生（24.44%）,散居儿童（20.00%）,商务工作者（11.11%）;女性发病率高于男性（P〉0.05）,男女性别比为0.72：1,差异无统计学意义。结论加强监测及提高重点人群疫苗的接种覆盖率是预防与控制风疹的主要措施。     

Primary investigation of 31 infants with suspected congenital rubella syndrome in Sudan

Between 2005 and 2006, clinical specimens were collected from 31 infants with suspected congenital rubella syndrome (CRS) who presented at six hospitals in Khartoum, Sudan. Eleven (35.5%) were laboratory confirmed as CRS cases by testing for anti-rubella IgM, IgG and viral genome. For the first time in Sudan, the rubella virus genome was directly detected in clinical specimens of six CRS cases and two viruses were isolated in cell culture. Phylogenetic analysis suggested that three genotypes of rubella virus (RV; 1E, 2B and 1G) were co-circulating in Sudan. The study introduced the methodology for CRS confirmation and surveillance in Sudan and provides preliminary data.     

广东省2005-2007年麻疹病原学监测

目的 开展有效的麻疹病原学监测,分离麻疹病毒,了解广东省2005-2007年流行的麻疹野病毒分离株基因特征,为控制、消除麻疹提供科学依据.方法 用Veto/Slam细胞从暴发和散发麻疹疑似病例的咽拭子和尿液标本中分离麻疹病毒,并对所有分离到的麻疹病毒通过逆转录-聚合酶链反应(RT-PCR)方法,扩增出核蛋白(N)基因碳末端450个核苷酸片段,对其产物测定基因序列以定型.结果 2005-2007年共收到380份标本,包括咽拭子或尿液标本.共分离到82株麻疹野病毒.2005年病毒分离率为23.58%,2006年病毒分离率为17.11%,2007年病毒分离率为39.13%.病毒分离成功率与病例出疹天数和标本的采集质量有密切关系.结论 我省已经掌握了麻疹病毒的分离和分子生物学鉴定技术,分离率较高;我省多年来流行的麻疹毒株均为H1基因型,与国内流行的优势基因型一致.     

Investigation of measles and rubella outbreaks in Tamil Nadu, India-2003

The aims of the present study were to confirm measles outbreaks by detection of measles-specific IgM antibodies, isolation of measles virus, and genetic characterization to document the circulating genotypes in Tamil Nadu. Eight outbreaks were reported from six districts of Tamil Nadu, India during the period Jan-Dec 2003. Blood samples were collected for serology, urine, and throat swabs for virus isolation. Genotypic characterization of measles isolates was based on the sequence of the N gene. All the clinically suspected outbreaks (n = 8) were confirmed by serology; six out of the eight as measles and two as combination of measles and rubella highlighting the need to carry out rubella serology on measles-negative samples. Genetic characterization of three isolates obtained revealed one as genotype D4 and two as D8. Measles genotypes D4 and D8 were found to circulate in three districts of Tamil Nadu. It is necessary to be aware of the circulating genotypes within the geographical area. The information would be valuable to evaluate control measures and identify viral transmission and importation.     

Seroprevalence of rubella infection after national immunization program in Taiwan: vaccination status and immigration impact

Rubella vaccination was implemented nationwide in 1992 in Taiwan. A cross-sectional survey was conducted to determine the age-specific seroprevalence of anti-rubella in female students aged 7-22 years old and women of reproductive age in Taipei County. Seropositivity of anti-rubella antibodies was defined as a serum IgG level > or =10 IU/ml tested by enzyme immunoassay. Information on possible predictors of anti-rubella seronegativity was obtained from structured questionnaire interview. Multivariate-adjusted odds ratios (ORm) with their 95% confidence interval (CI) were derived for each predictor using multiple logistic regression analysis. A total of 826 female students and 318 women were recruited. Anti-rubella seropositive rates were 98.3% (282/287), 99.6% (234/235), 96.8% (179/185), 92.4% (110/119), 81.4% (197/242), and 89.5% (68/76) for the age groups of 7-9, 11-13, 15-17, 19-22, 25-33, and 34-44 years old, respectively. Among female students, negative serology for rubella antibodies was associated significantly with the age group and foreign nationality of mother, showing ORm (95% CI) of 1.2 (1.06-1.27) for each year increase in age, and 20.9 (6.31-68.97), respectively. Among women at the reproductive age, low maternal education level 91.6 (9.12-920.74), unmarried status 21.2 (6.16-72.89), and no rubella vaccination 98.9 (11.64-840.25) were associated significantly with an increased evidence of seronegativity to rubella. The National Rubella Vaccination Program has led to herd immunity of school girls. However, in order to eradicate the Rubella syndrome, greater effort is required to vaccinate foreign brides in Taiwan.     

Nationwide laboratory-based surveillance of invasive beta-haemolytic streptococci in Denmark from 2005 to 2011

The aim of this work was to describe national surveillance of invasive beta-haemolytic streptococci (BHS) in Denmark and to report overall trends and major findings by groups and types of BHS causing laboratory-confirmed disease from 2005 to 2011. A total of 3063 BHS isolates were received from 2872 patients. Based on confirmed cases the overall annual incidence increased from 6.2 to 8.9 per 100 000 persons between 2005 and 2011. In 2011 the incidences of group A, B, C and G streptococci were 3.1, 2.3, 0.9 and 2.6 per 100 000 persons, respectively. An increase was observed for all groups of BHS, but in particular for group G in men above 65 years of age. Among group A streptococci (GAS), five T-types (1, 28,12, 3,13,B3264 and B3264) represented 71% and five emm-types (1, 28, 3, 89 and 12) 76% of all isolates. Among group B streptococci (GBS) four types (III, Ia, V, Ib) represented 79% of the isolates. Potential coverage for future vaccines against GAS and GBS disease was 76% compared with the 26-valent GAS vaccine and 89% based on GBS serotypes Ia, Ib, II, III and V. The number of reported cases of invasive BHS disease increased in Denmark from 2005 to 2011. Nationwide laboratory-based surveillance of BHS is required to monitor epidemiological changes, explore potential outbreaks and determine potential vaccine coverage.     

Application of molecular and serological assays to case based investigations of rubella and congenital rubella syndrome

Rubella and congenital rubella syndrome continue to be important health problems worldwide. The detection of rubella RNA directly in clinical specimens is a critical factor in early laboratory diagnosis of recent or congenital infection, in addition to detection of rubella-specific IgM. In order to comply with recent WHO recommendations for establishing uniform genetic analysis protocols for rubella virus we have developed a new block based PCR assay (PCR-E317), which extends the sequence generated by the block based PCR-E592 currently in use, to cover the minimum acceptable 739 nucleotides (nt) window at the E1 gene. In addition, a real-time PCR assay has been developed to allow rapid detection of the virus in the laboratory. The assays were applied to a number of clinical specimens collected from patients including recent rubella incidences in the UK, Ethiopia and Turkey, two prenatal and two congenital rubella syndrome cases. Rubella RNA was detected in specimens from two patients that were collected too early for IgM detection, in two amniotic fluids for prenatal diagnosis and in the follow up specimens from the two infant with congenital rubella syndrome tested for viral secretion. At least four genotypes were identified among these patients. The results showed that molecular assays are important tools in the early diagnosis of rubella and congenital rubella syndrome, in the provision of molecular epidemiological information for tracking transmission pathways and in adding to the knowledge of rubella strain distribution worldwide.     

2010—2011年西城区（南区）手足口病原监测结果分析

目的对2010—2011年北京市两城区（_幸j区）手足口病患者进行肠道病毒病原体检测,分析肠道病毒病原学特征,为手足口病防控提供科学依据。方法采集医疗机构临床诊断为手足r1病患者咽拭子和粪便标本共418份,应用Realtime—PCR检测咽拭子标本病毒核酸;并对粪便标本进行病毒分离。结果418份标本中,肠道病毒总体检出率为53．59％（224／418）。2010年咽拭子标本未分型肠道病毒阳性枪出率（36．26％）高于2011年（16．89％）,结果差别有统计学意义（X^2=13．80,P〈0．005）;2011年咽拭子标本CoxA16型病毒阳性检出率（26．03％）高于2010年（10．99％）,差别有统计学意义（x^2=8．58,P〈0．005）。分别比较两年采集的咽拭子标本,发病3大内和3天以上采集的标本检出率差异均有统计学意义（2010年：x^2=5．85,P〈0．05;2011年：X^2=15．26,P〈0．005）。结论引起北京市西城区（南区）手足口病流行的主要肠道病原体,2010年为未分型肠道病毒,2011年为CoxA16。在发病3天内采集患者咽拭子标本,有助于提高病毒检出率。     

Application of new assays for rapid confirmation and genotyping of isolates of rubella virus

Rubella virus (RV) isolation is recommended by the WHO Measles and Rubella Labnet for studying the etiology and epidemiology of rubella. However, the absence of cytopathologic effects (CPE) in many of the cell lines used commonly makes it difficult to confirm RV growth. In this study, two assays amplifying RV cDNA were developed and validated in order to confirm and genotype RV isolates after cell culture. A SYBR Green I-based real-time PCR (Rtime-SGE317) was established for initial rapid detection of RV in Vero cells and a nested PCR (PCR-E860) was used for amplifying further the 739 nt window of the E1 gene for the identification of RV genotype as recommended by the WHO. Sensitivities of the two assays were evaluated using eight RV isolates, two from infants with the congenital rubella syndrome (CRS) and six from patients with acute rubella. All the isolates had cycle threshold (C(t)) values <37 after the third passage, which is recommended as the cut-off for the confirmation of a viable RV isolate. Phylogenetic analysis based on the 739 nt window generated by the PCR-E860 showed that the eight RV isolates belonged to genotypes 1E, 1G, and 2B. The Rtime-SGE317 assay can be carried out in local public health laboratories, which would extend the molecular surveillance of rubella and contribute to the WHO goal of eradicating rubella worldwide.     

孕前及孕期妇女风疹免疫力调查和风疹近期感染检测

目的了解孕前妇女及孕期妇女风疹易感水平和近期感染状况，为预防先天风疹感染做好优生优育工作提供依据。方法用生物蛋白芯片技术对2986例孕前妇女及863例孕期妇女（包括725例正常妊娠和138例异常妊娠）进行风疹特异性抗体IgM、IgG检测。结果80．27％的孕前妇女具有免疫力，4．99％孕前妇女为风疹近期感染，14．03％妇女对风疹易感。89．00％的孕期妇女具有免疫力，1．96％孕期妇女为风疹近期感染，7．76％妇女对风疹易感。孕前妇女及孕期妇女的风疹近期感染率和易感率比较有显著性差异（χ^2=14．797、23．846，P〈0．001）；不良妊娠与正常妊娠之间风疹近期感染率和易感率比较有显著性差异（X。=30．635、4．174，P〈0．05）；市区与农村的孕前妇女及孕期妇女在风疹近期感染率和易感率比较无明显不同；孕前妇女及孕期妇女风疹近期感染月份分布均以5月最高。结论本地区孕前妇女风疹感染率高；风疹感染与不良妊娠密切相关：市区与农村妇女的风疹易感水平和近期感染状况相当。对孕前妇女及孕期妇女同时检测风疹特异性抗体IgM、IgG可以正确判定妇女的免疫状况，有效预防、主动发现并合理处理孕妇感染，从而降低风疹感染率提高优生优育水平。     

Hemagglutination inhibition,single radial hemolysis,and ELISA tests for the detection of IgG and IgM to rubella virus

Hemagglutination inhibition (HI), single radial hemolysis (SRH) and enzyme-linked immuno sorbent assay (ELISA), performed with commercial antigen and reagents are described and were compared in the three distinct situations that require rubella antibody detection. Determination of immunity status was carried out on 156 sera. A degree of correlation > 0.9 was found when comparing the three methods. Analysis of a further 74 sera, from 31 primary infections and three congenital syndromes, was performed to compare the occurrence of the various classes of antibodies in the three tests: HI test and IgM-ELISA become positive the day after the rash, whereas SRH test is not positive before the sixth day. From our limited study bearing on a total of 230 sera, each test has a precise assignment. For the determination of immunity status, SRH is simpler, faster, and inexpensive; absence or evidence of past infection can be unequivocally obtained especially in cases of low (1:10, 1:20) residual immunity. In the seriodiagnosis of a rubella rash, SRH alone, due to the delayed rise in antibody titers, will demonstrate a complete seroconversion with a first serum collected up to the fifth day of the eruption. In case of absence of an early serum, of primary infection in a pregnant woman, of a newborn with suspicion of congenital syndrome, the measurement of rubella specific IgM is best obtained with ELISA, a procedure less time-consuming than HI following centrifugal, chromatographic, or electrophoretic separation. And “light” (8 S) RF with SRH test is discussed. Interference of IgM Rheumatoid Factor (RF) with IgM ELISA and IgG RF with SRH test is discussed.