Human Brucella canis Infection and Subsequent Laboratory Exposures Associated with a Puppy,New York City, 2012

Human Brucella canis infection incidence is unknown. Most identified cases are associated with pet dogs. Laboratory‐acquired infections can occur following contact with Brucella spp. We identified a paediatric B. canis case, the source and other exposed persons. A 3‐year‐old New York City child with fever and dyspnoea was hospitalized for 48 h for bronchiolitis. After her admission, blood culture grew B. canis, she was prescribed anti‐microbials and recovered. B. canis was also isolated from blood of the child's pet dog; these isolates were genetically similar. The dog originated from an Iowa breeding facility which was quarantined after identification of the dog's infection. Additionally, 31 laboratory workers were exposed and subsequently monitored for symptoms; 15 completed post‐exposure prophylaxis. To our knowledge, this is the first report strongly suggesting B. canis zoonotic transmission to a child in the United States, and highlights the need for coordinated control policies to minimize human illness.     

哈萨克羊DRB1基因外显子3多态性及生物信息学分析

试验旨在研究白细胞表面抗原DRB1基因外显子3多态性与哈萨克羊布鲁氏菌病易感性的相关性。运用混合DNA池结合PCR产物直接测序方法,对哈萨克羊DRB1基因外显子3进行多态性分析,经卡方检验分析每个SNP位点的等位基因频率、基因型频率及其多态性与布鲁氏菌病易感性的相关性,利用生物信息学分析软件对PCR扩增所获序列进行RNA二级结构及蛋白质的二级结构和抗原表位分析。结果表明,在282 bp的外显子3序列中共检测到7个SNPs,分别为：T10C、C119T（Trp→Arg）、G215C（Gln→Glu）、A238G、T245G（Ser→Ala）、G256A、C259T,这些位点在病例组和对照组之间的等位基因频率及各基因型间不存在显著性差异（P > 0.05）;进一步分析发现,各突变位点均引起RNA二级结构和最小自由能的改变,各错义突变位点均未引起蛋白质二级结构和抗原表位的改变。由此得出,DRB1基因外显子3的7个SNPs位点（T10C、C119T、G215C、A238G、T245G、G256A和C259T）与哈萨克羊布鲁氏菌病易感性无相关性。     

河南省某县羊群布鲁菌氏病横断面调查及感染风险因素分析

为了解河南省羊布鲁氏菌病流行现状以及羊养殖场感染风险因素,按照两阶段抽样检测方法,采集某县羊养殖场和散养村的羊血清样品,采用虎红平板凝集和试管凝集垂直试验进行布鲁氏菌检测。结果显示,该县散养村的羊布鲁氏菌病表观群体流行率为16.35%,真实群流行率为18.17%(95%CI:12.14%~24.20%),养殖场的表观群体流行率为22.22%,真实群流行率为25.60%(95%CI:13.87%~37.33%)。风险因素分析结果显示,“羊贩随意进出养殖场(OR=18.50,95%CI:1.82~188.39)”和“共用种公羊(OR=12.00,95%CI:1.11~129.42)”是该县羊养殖场感染布鲁氏菌的主要风险因素。结果表明,该县羊布鲁氏菌病流行较为严重,提示该县需要加强布鲁氏菌病防控,提高养羊场户的生物安全管理水平,加强散养村内种公羊的布鲁氏菌监测与净化,及时淘汰阳性羊。     

天津市布鲁氏菌病高发区高危人群“知信行”调查

为了解天津市布鲁氏菌病高发区高危人群的布鲁氏菌病防控知识、态度和行为水平及其相关影响因素,以便为下一步宣传干预工作提供参考,基于问卷调查和电话回访的横断面调查研究,对天津市4个布鲁氏菌病高发区牛羊养殖户、基层兽医人员进行抽样调查,然后调查数据录入Excel,使用SPSS软件进行统计分析,查找影响布鲁氏菌病"知信行"水平的因素。结果显示:高危人群的布鲁氏菌病平均知晓率为44.93%,大部分高危人群对布鲁氏菌病防控态度积极,部分基层兽医人员和养殖户对布鲁氏菌病防控存在不良行为和不良防护习惯;单因素Logistic回归分析可见,布鲁氏菌病高危人群的"知信行"水平与职业、性别、学历、工作年限有关(P <0.05);多因素Logistic回归分析显示,牛羊养殖户、工作年限小于10年的高危人群"知信行"水平较低(P<0.05),模型拟合度较好(P> 0.05),ROC曲线下面积(AUC)为0.732(95%CI:0.673～0.791)。结果表明,牛羊养殖户、工作年限小于10年的高危人群,其布鲁氏菌病"知信行"水平有待提高,需要在未来宣传干预中,提高培训的针对性、实用性、专业性,拓展渠道,注重效果。     

Diagnosis of canine brucellosis by ELISA using an antigen obtained from wild Brucella canis

An indirect ELISA test was developed for the diagnosis of Brucella canis infection in dogs. A bacterial whole cell extract was used as a solid phase antigen, using B. canis isolated from an infected animal. Sera from culture-positive and healthy negative animals were used as internal reference controls. The cut-off point was determined by a mathematical formula for a statistically valid value, which defined the upper prediction limit, based on the upper tail of the t-distribution of 21 negative control sera readings, for the confidence level of 99.5%. The sensitivity and specificity of the ELISA test were 95% and 91%, respectively. The ELISA test showed a significant concordance index (K=0.84) with the agar gel immunodiffusion test. The reliability of the ELISA for the detection of infected animals was established by a double blind study testing 280 sera provided by serum banks from different diagnostic and research institutions and analyzed by ROC Curve.     

An evaluation of Irish cattle herds with inconclusive serological evidence of bovine brucellosis

Since 1998, there has been a steady decline in herd restrictions and de-populations in Ireland due to bovine brucellosis. There is concern that the interpretation of laboratory results may become increasingly problematic, as brucellosis prevalence falls in Ireland. Therefore, the purpose of the current study was to evaluate the infection status of Irish herds and animals with inconclusive serological evidence of bovine brucellosis. During 12 months from September 1, 2004, laboratory and observational epidemiological data were collected from all Irish herds where animal testing identified at least one animal with a complement fixation test (CFT) reading greater than zero and/or a positive result to the indirect enzyme-linked immunosorbent assay (iELISA). Due to the observational nature of the study, we have robust estimates of the relative, but not the absolute, performance of the CFT, iELISA and brucellin skin test (BST). Herds were divided into three categories (Group A, B or C) on the basis of test results at initial assessment. A total of 639 herds were enrolled into the study, and observed for at least two years following enrolment. A rising CFT titre, with a CFT reading of 111 International CFT Units (IU) or greater at the subsequent blood test, was generally associated with herds where other evidence of infection was also available. Knowledge of the CFT reading at the initial and a subsequent blood test proved useful in distinguishing false-positive and true-positive brucellosis results. There was poor correlation between the CFT and iELISA results, and between the CFT and BST results. As a result of this study, national policy has been modified to include re-sampling of all animals with CFT readings of 20 IU or greater. This project has also led to a reduction in the number of herds restricted, as well as restriction duration. It has also contributed to a reduction in the number of herds listed for contiguous tests, and therefore the potential for contiguity testing of false positive results.     

Use of Mass Vaccination with a Reduced Dose of REV 1 Vaccine for Brucella melitensis Control in a Population of Small Ruminants

Mass vaccination with reduced dose 1/50 Rev 1 strain live vaccine (1–2 109 colony forming units), administered subcutaneously, over a four and a half year period reduced the prevalence of Brucella melitensis in Kuwait's small ruminant population from 5.8% in 1993 to 2.02% in 1997.Serological test results using the Rose Bengal Plate Test, Rivanol Agglutination Test and Complement Fixation showed no evidence of persistence of positive serology in animals nine or more months after vaccination. Questionnaires and post-vaccination flock inspections found that the effects on gestation (abortions) were minimal – and not proven to be due to the vaccine.The conclusion from these findings is that mass vaccination with reduced dose Rev 1 administered by the subcutaneous route is a practical field strategy for control of Brucella melitensis.     

Serological survey of pre-weaned New Zealand fur seals (Arctocephalus forsteri) for brucellosis and leptospirosis

AIM: To conduct a longitudinal serological survey for evidence of Brucella spp and Leptospira spp infection of pre-weaned New Zealand fur seals in a colony on the Otago Peninsula.

METHODS: Seal pups were repeatedly captured on a monthly basis from February through to July 2001. Pups were tagged at first capture and a blood sample was taken at each capture event. A total of 163 sera were collected from 118 seal pups. Where sufficient volume was collected, the sera were tested for leptospirosis using the microscopic agglutination test (MAT), and for brucellosis using the competitive enzyme-linked immunosorbent assay (ELISA) for Brucella abortus.

RESULTS: None of 128 sera from 101 seals tested positive to the ELISA for B. abortus. All tests for Leptospira interrogans serovars Grippotyphosa, Copenhageni, Bratislava and Leptospira borgpetersenii serovar Ballum were negative at a cut-off of <1/100 dilution. Positive or suspicious titres were found to L. interrogans serovars Canicola and Pomona and L. borgpetersenii serovar Hardjo. The highest titres (12,800) were found to serovar Pomona. The titre to serovar Pomona in one seal rose from <1/50 in March to 12,800 in April and was <1/50 when re-sampled in July. The titre to serovar Pomona in another seal dropped from 12,800 in May to <1/50 in June. These seals also had titres to serovar Hardjo, which rose or fell in the same manner. All suspicious or positive titres occurred in late April and early May, when the pups were approximately 4–5 months old. In June and July, all seals tested were negative.

CONCLUSIONS: There was no serological evidence of Brucella infection in the pre-weaned fur seals at the colony. Positive titres to serovars Pomona, Hardjo, or Canicola suggest that a Leptospira species was present at the colony, however isolation or visualisation of the organism is required to confirm this. Care should be exercised when handling New Zealand fur seals to prevent human infection or inadvertent transfer of leptospirosis to another marine mammal species.     

牛羊布鲁菌病（brucellosis）的诊断方法

布鲁菌病是一类由各型布鲁菌感染而引起的重要的人畜共患病之一。被感染的动物最常见的临床表现为流产、胎盘炎、附睾炎、睾丸炎等。人感染布鲁茵病后,多呈慢性经过,可损害人体多种器官。虽然病原学鉴定是一种常规有效的诊断布鲁茵病的方法之一,但由于其对操作人员安全以及实验室级别的要求非常严格,加之从患病动物体内分离病原体的过程既耗时又具有危险性,在布鲁茵病临床诊断实践中推广应用困难。布鲁菌病血清学诊断方法显示出较高的特异性和敏感性．但难以鉴别布鲁菌各型野毒株以及疫苗株感染。鉴于上述问题．深入开发和研制更高特异性、敏感性和稳定性的新型布鲁茵病诊断方法在兽医临床实践中势在必行。主要从细菌学、血清学和分子生物学等方面对布鲁茵病诊断方法研究情况进行了综述,以期为相关研究提供参考。