Serological and bacteriological study of brucellosis in camels in central Saudi Arabia.

Sera from 2,630 apparently normal adult camels (Camelus dromedarius) raised in central Saudi Arabia (Riyadh and Al-Kharj cities) were examined serologically by the Rose Bengal and standard United States of America Brucella plate agglutination tests. The overall seroprevalence of brucellosis in the restricted populations of tested camels was 8%. The seroprevalence of brucellosis among camels raised in small numbers in the backyards of 24 houses in Riyadh and those intensively raised on one large camel farm near Al-Kharj were 4.3% and 8.6% respectively. Fresh milk samples from 100 brucellosis seropositive camels from Riyadh and Al-Kharj were cultured on Brucella-selective media. Brucella melitensis biovars 1 and 2 were isolated and identified from 26 camels. Epidemiologically, brucellosis in camels in central Saudi Arabia appeared to be connected with B. melitensis infection of sheep and goats, and also represents a serious public health risk.     

2011-2017年沈阳市人间布鲁氏菌病流行病学分析

目的 对2011-2017年沈阳市确诊的布鲁氏菌病(布病)病例流行病学特征进行分析,为制定更具针对性的防治策略提供科学依据。方法 收集整理2011-2017年布病疫情信息和监测数据,并进行描述性流行病学分析。结果 2011-2017年沈阳市共报告布病1 805例,年均发病率为3.82/10万;发病集中在35~65岁之间,占总发病数的74.57%;男性发病多于女性,男女比例为2.98〖DK〗∶1;职业人群布病抗体阳性率为3.43%;病原学监测分离到9株布鲁氏杆菌,分别为2株羊种Ⅰ型和7株羊种Ⅲ型。结论 沈阳市布病疫情明显增加,处于流行高峰。人间布病疫情由染疫的羊引起,流行优势菌株为羊种Ⅲ 型)。     

Field investigations of brucellosis in cattle and small ruminants in Syria, 1990-1996.

The authors present the epidemiological status of brucellosis in cattle and small ruminants in Syria from 1990 to 1996, based on laboratory findings at the Brucellosis Centre, Damascus. Initial investigations using the Rose Bengal plate test, the complement fixation test and a miniaturised variant of the slow agglutination test were conducted throughout the country in 1990 and 1991, revealing an overall herd seroprevalence rate of 3.14% in cattle herds and 2.94% in small ruminant flocks. Although partially biased by previous vaccination of young female cattle with S19 vaccine, these figures indicate that brucellosis in cattle is widespread, particularly in the urban governorates (provinces) of Damascus, Aleppo and Suwaydah. Brucellosis seroprevalence in sheep and goats was relatively high in the governorates of Damascus, Aleppo and Dara'a. The results of a second series of investigations, performed between 1992 and 1996, show that herd seroprevalence in cattle decreased steadily from 17.48% in 1992, to 2.59% in 1996, in the Government-owned farms, while seroprevalence increased in the private sector during the same period. The difference may be explained by the restriction of brucellosis vaccination to public farms (although this was far from systematic), combined with partial application of a 'test-and-slaughter' policy. In sheep and goats, brucellosis seroprevalence fluctuated in the two sectors, but was higher in the private sector where husbandry is principally extensive. Bacteriological investigations led to the isolation of Brucella melitensis biovars 2 and 3 in sheep and B. abortus biovar 9 in cattle. Although no specific methodology was employed, particularly with regard to sampling, this study is significant as the first international report of the distribution of brucellosis in Syria. Further, well-structured studies are required, the results of which could be used to plan an appropriate national control programme for brucellosis.     

1999-2008年辽宁省朝阳市布鲁氏菌病流行病学监测分析

目的通过对朝阳市1999-2008年布鲁氏菌病（布病）的流行病学监测资料进行分析,推断布病流行菌种,找出主要传染源,为布病防治工作提供科学依据。方法采用流行病学监测方法,于1999-2008年对重点地区的重点人群、全市7个县（市、区）的散发病例及暴发病例、畜间牛、羊开展血清学检测。通过对3类群体的血清进行抗体检测,运用Spearman相关的分析方法,找出人群年发病数与牛、羊存栏数,人群年发病数与牛、羊血清抗体阳性率,重点人群血清抗体阳性率与牛、羊血清抗体阳性率的关系。结果人群年发病数与牛、羊存栏数及与羊血清阳性率明显相关（r=0.779,P〈0.01;r=0.816,P〈0.01;r=0.857,P〈0.01）;2009年对18例布病患者进行病原菌血培养,有2株为布鲁氏菌羊种菌3型。结论朝阳市布病以羊种菌为主要流行菌种,在防治中羊应作为主要的监管对象。     

遵义市1起布鲁菌病疫情调查

目的 对遵义市2011年务川县1起布鲁菌病(布病)疫情进行流行病学调查,为科学制定防治措施指导布病防治工作提供依据.方法 采用现场流行病学调查,实验室采用虎红平板凝集试验和试管凝集试验对羊间和人间所采集的血清标本进行检测.结果 该疫情共报告确诊病例2例,2例患者为夫妻,血培养结果为马尔他布鲁菌;2008年由务川县畜牧部门引进羊种免费投放从事山羊养殖,系因接触新生羊羔或母羊产道分泌物而感染,属本土病例,患者村羊血标本布病抗体阳性检出率为17.17％(17/99),病家羊血标本阳性检出率为85％ (17/20).遵义市2010年以前无该病报告.结论 布病是遵义市新发的人畜共患传染病,个别地区存在布病疫源地,应引起重视.     

Evaluation of Brucella melitensis B115 as rough-phenotype vaccine against B. melitensis and B. ovis infections

Brucella melitensis strain Rev1 is used as vaccine for the prophylaxis of brucellosis in sheep and goats. Because of its smooth phenotype, however, it induces antibodies directed to the O-polysaccharide (O-PS) of the lipopolysaccharide (LPS), thus unabling to distinguish between vaccinated and infected animals. It has been speculated that alternative vaccines could be live, attenuated Brucella rough strains, which are devoid of the O-PS. B. melitensis B115 is a natural, attenuated, rough strain. The O-PS is not exposed at the surface but is present in the cytoplasm. We tested the protective activity of B115 against B. melitensis and B. ovis infections in mice, in comparison with that of Rev1. The residual virulence and the humoral response following B115 vaccination were also evaluated. Vaccination with B115 conferred significant protective immunity against B. melitensis 16M and B. ovis challenge strains, equivalent to that provided by Rev1. No interfering antibodies to O-PS were detected, while the B115 vaccination was monitored by a specific B115-based complement fixation test. These promising features suggest further evaluation of B. melitensis B115 as vaccine for target animal hosts.     

Comparison of serological tests for the detection of ovine and caprine antibody to Brucella melitensis

The indirect enzyme-linked immunosorbent assay (IELISA), the competitive enzyme-linked immunosorbent assay (CELISA) and the fluorescence polarisation assay (FPA) were evaluated with sera from sheep experimentally infected with Brucella melitensis and negative Canadian sheep. The sensitivity and specificity of the assays were as follows: IELISA: 91.7% and 97.6%, CELISA: 75.0% and 99.8% and FPA: 91.7% and 89.5%. Sera from the same experimental population were divided according to serological reaction in the rose bengal agglutination test (RBT) and the complement fixation test (CFT). Reactivity relative to the RBT positive and CFT positive sera were as follows: IELISA: 99.7%, CELISA: 93.2% and FPA: 99.1%. Since sera from goats with proven B. melitensis infection were not available, 699 sera from goats judged positive in the buffered antigen plate agglutination test (BPAT) and CFT and 982 BPAT/CFT negative Canadian goats were used. The sensitivity and specificity of the assays relative to the BPAT and CFT positive sera were: IELISA: 99.4% and 98.0%, CELISA: 95.4% and 97.1% and FPA: 92.7% and 99.8%.     

Comparison of the efficacy of Brucella abortus strain RB51 and Brucella melitensis Rev. 1 live vaccines against experimental infection with Brucella melitensis in pregnant ewes.

To test the efficacy of rough Brucella strain vaccines in sheep, a vaccine recently developed in cattle (Brucella abortus strain RB51) was assessed in comparison with the conventional Rev. 1 vaccine. Forty-five ewes from twelve to fourteen months of age, from brucellosis-free flocks, were allotted to three groups of fifteen ewes each. Group one was vaccinated by the conjunctival route with 1.73 x 10(8) colony forming units (CFU) of Rev. 1 vaccine. Group two was vaccinated subcutaneously with 11 x 10(9) CFU of RB51 vaccine and group three was considered as a control. All sheep were challenged at two to three months of gestation with 5 x 10(7) CFU of virulent B. melitensis H38. Vaccination with RB51 vaccine did not result in the production of any antibodies against the O-side chain of lipopolysaccharide, as measured by conventional serological tests (Rose Bengal plate test and complement fixation test). Protection of sheep against abortion and excretion of virulent Brucella strain in vaginal fluid, aborted foetuses and/or non viable lambs at parturition and abortion was significantly lower than that afforded by Rev. 1 vaccine. The difference compared to the control group was not significant. Data from this study suggest that the RB51 vaccine used for cattle vaccination does not provide effective protection of sheep against abortion induced by B. melitensis.     

Brucellosis at the dawn of the 21st century

Human brucellosis is now a rare disease in countries where eradication programs (especially vaccination) against brucellosis in cattle, sheep, and goats have been successfully implemented. In France, fewer than 50 brucellosis cases are annually notified to the National Institute for Infection Surveillance. Human brucellosis, however, remains endemic in the Mediterranean basin, Middle East, Western Asia, Africa, and South America. Shortcomings of standard diagnostic methods for brucellosis (variable sensitivity of culture, frequent serological cross reactions) have been only partially resolved by modern molecular biology techniques. There are now 3 new challenges to be faced by the medical and veterinarian community: the expanding wildlife reservoir of brucellosis, with a possible impact on domestic animals; the emergence of Brucella. melitensis infections in cattle, for which prophylactic efficacy of available vaccines has not been established; and recent recognition of a huge animal reservoir of Brucella species in marine mammals, for which the potential virulence in humans remains unknown.     

Brucellosis: an overview.

Brucellosis remains a major zoonosis worldwide. Although many countries have eradicated Brucella abortus from cattle, in some areas Brucella melitensis has emerged as a cause of infection in this species as well as in sheep and goats. Despite vaccination campaigns with the Rev 1 strain, B. melitensis remains the principal cause of human brucellosis. Brucella suis is also emerging as an agent of infection in cattle, thus extending its opportunities to infect humans. The recent isolation of distinctive strains of Brucella from marine mammals has extended its ecologic range. Molecular genetic studies have demonstrated phylogenetic affiliation to Agrobacterium, Phyllobacterium, Ochrobactrum, and Rhizobium. Polymerase chain reaction and gene probe development may provide more effective typing methods. Pathogenicity is related to production of lipopolysaccharides containing a poly N-formyl perosamine O chain, CuZn superoxide dismutase, erythrlose phosphate dehydrogenase, stress-induced proteins related to intracellular survival, and adenine and guanine monophosphate inhibitors of phagocyte functions. Protective immunity is conferred by antibody to lipopolysaccharide and T-cell-mediated macrophage activation triggered by protein antigens. Diagnosis still centers on isolation of the organism and serologic test results, especially enzyme immunoassay, which is replacing other methods. Polymerase chain reaction is also under evaluation. Therapy is based on tetracyclines with or without rifampicin, aminoglycosides, or quinolones. No satisfactory vaccines against human brucellosis are available, although attenuated purE mutants appear promising.     

Incidence, etiology and epidemiology of brucellosis in a rural area of the province of Lleida

BACKGROUND: This a prospective study of the incidence, etiology and epidemiological profile of human brucellosis in the regions of Pallars Jussà y Sobirà (Lleida) for the 1995-1998 period. METHODS: Fifty-five patients diagnosed as having brucellosis were studied. Information was recorded regarding the gender, age, town where residing, occupational hazard, contact with animals and intake of unsterilized dairy products, blood samples having been taken for blood cultures. RESULTS: A total of ten cases were reported in 1995, fourteen in 1996, fifteen in 1997 and sixteen in 1998, the average cumulative rates being 52 in Pallars Jussà and 129 in Pallars Sobirà. Four times more cases were reported among males (81.8%) than among females (18.2%) (RR: 4.4; CI95% 2.2-8.7). The largest number of cases occurred in March-April, and the fewest during the summer months. Seventy-one percent (71%) of these patients were working at an occupation involving this risk, the direct contagion mechanism being clearly prevalent (71%). The animal species most frequently considered to be the source of infection was that of sheep (65%), followed by cows (47%) and goats (25%). In Pallars Jussà, mainly sheep (RO: 0.3 CI95% 0.1-0.9) and in Pallars Sobirà, cows (RO: 6.6; CI95% 1.8-26.2). Twenty-seven strains of Brucella sp, all of the melitensis species, were isolated. CONCLUSIONS: The number of cases of brucellosis in the regions studied have risen in the 1995-1998 period. The results of study of this are indicative of the characteristic profile of an occupational disease. The etiological agent was Brucella melitensis, biovariety 1 clearly being the most prevalent.     

Abortion due to Brucella abortus in sheep in Nigeria

This paper reports on a sporadic, naturally acquired infection of sheep with Brucella abortus on a privately owned farm in Toro near Bauchi, Nigeria. The abortions, which occurred in a flock of 28 Yankassa sheep, involved five ewes at the third month of gestation. Serum and milk samples from the flock were examined for Brucella antibodies by the Rose Bengal plate test, serum agglutination test (SAT) and milk ring test (MRT). The proportion shown as positive by SAT was 14.3%. All the five milk samples examined by MRT were positive. A total of seven isolates of Brucella were obtained from three milk samples and four vaginal swabs collected from aborting ewes. All isolates were identified and biotyped as B. abortus biovar 1. This biovar was also isolated from cattle maintained on the farm in association with the sheep. The infection was attributed to the animal husbandry practices employed on the farm.     

Treatment of Brucella melitensis infection in sheep and goats with oxytetracycline combined with streptomycin.

Six treatment regimens using oxytetracycline (OTC) combined with streptomycin (ST) were evaluated for eliminating Brucella melitensis from 480 naturally-infected sheep and goats. Cessation of shedding Brucella from udder secretions and absence of Brucella in selected tissues at autopsy were considered criteria for successful treatment. Four regimens were equally effective in eliminating Brucella in the treated groups of sheep and goats regardless of the source of antibiotics used. These were regimen A (OTC 20 mg/kg intravenously daily for 6 weeks, combined with ST 20 mg/kg intramuscularly [i.m.] daily for 3 weeks), regimen B (long-acting [LA]-OTC 20 mg/kg i.m. every 3 days for 6 weeks, with ST 20 mg/kg i.m. every 3 days for 3 weeks), regimens D and E (LA-OTC 28 mg/kg i.m. every 3 days for 6 weeks, with ST 20 mg/kg i.m. every 3 days for 3 weeks). However, regimen C (LA-OTC 20 mg/kg i.m. every 3 days for 6 weeks, with ST 20 mg/kg i.m. every 3 days for 3 weeks) eliminated Brucella in only 75 of 80 (94%) sheep and goats. Regimen F (LA-OTC 25 mg/kg i.m. every 2 days for 4 weeks, combined with ST 20 mg/kg i.m. every 2 days for 2 weeks) was the most practical, effective and least expensive regimen for eliminating Brucella in the 80 treated sheep and goats. Brucella melitensis biovar 2 was repeatedly isolated from the mammary secretions of all sheep and goats before treatment. It was also isolated repeatedly from the udder secretions of all non-treated control animals and from selected tissue specimens collected from the controls at necropsy.     

Brucellosis: serological methods compared

At least 12 persons contracted clinical, and 4 persons subclinical Brucella melitensis infection during a brucellosis epidemic in the spring and summer of 1983 in Southern Germany, a region which had been free of this disease for the past 20 years. All cases of illness were traced to one infected herd of sheep. The presence of antibodies against B. melitensis was examined in 72 sera of infected patients using the following tests: agglutination, Coomb's test, two complement fixation tests with different antigen preparations (CFT 1 and 2), IgG and IgM enzyme-linked immunosorbent assay (ELISA), and opsonophagocytosis; and the occurrence of cross-reacting antibodies against Yersinia enterocolitica O 9 was investigated in the agglutination and complement fixation tests. Sera from 100 blood donors and 112 other people with close contact with sheep were also examined. The results revealed the need to consider an intermediate range in the interpretation of ELISA results--due to elevated values of persons in groups at risk but without clinical signs of illness. In all other tests, however, such persons revealed the same cut-off levels as the general population. Results from all initial sera of infected persons revealed titres of optical densities above the baseline levels determined in the present study, with the exception of the Coomb's and CFT2 tests. The agglutination test, but not brucella CFT2, revealed complete cross-reactivity between Y. enterocolitica O 9 and B. melitensis. ELISA stood out as the only test which is suited to diagnosis of both recent and past infection, since ELISA IgM determination permits conclusions about the time of the onset of illness, and determination of IgG may still yield values above the cut-off level up to 623 days after the onset of illness. In 2 of the 16 infected persons, IgG ELISA was the only test revealing previous infection 424 and 528 days after the onset of illness. A procedural scheme is presented which may help to simplify the diagnosis of brucellosis.     

Brucellosis: serological methods compared.

At least 12 persons contracted clinical, and 4 persons subclinical Brucella melitensis infection during a brucellosis epidemic in the spring and summer of 1983 in Southern Germany, a region which had been free of this disease for the past 20 years. All cases of illness were traced to one infected herd of sheep. The presence of antibodies against B. melitensis was examined in 72 sera of infected patients using the following tests: agglutination, Coomb''s test, two complement fixation tests with different antigen preparations (CFT 1 and 2), IgG and IgM enzyme-linked immunosorbent assay (ELISA), and opsonophagocytosis; and the occurrence of cross-reacting antibodies against Yersinia enterocolitica O 9 was investigated in the agglutination and complement fixation tests. Sera from 100 blood donors and 112 other people with close contact with sheep were also examined. The results revealed the need to consider an intermediate range in the interpretation of ELISA results--due to elevated values of persons in groups at risk but without clinical signs of illness. In all other tests, however, such persons revealed the same cut-off levels as the general population. Results from all initial sera of infected persons revealed titres of optical densities above the baseline levels determined in the present study, with the exception of the Coomb''s and CFT2 tests. The agglutination test, but not brucella CFT2, revealed complete cross-reactivity between Y. enterocolitica O 9 and B. melitensis. ELISA stood out as the only test which is suited to diagnosis of both recent and past infection, since ELISA IgM determination permits conclusions about the time of the onset of illness, and determination of IgG may still yield values above the cut-off level up to 623 days after the onset of illness. In 2 of the 16 infected persons, IgG ELISA was the only test revealing previous infection 424 and 528 days after the onset of illness. A procedural scheme is presented which may help to simplify the diagnosis of brucellosis.     

Distribution of brucellosis among small ruminants in the pastoral region of Afar, eastern Ethiopia

A cross-sectional study was conducted in the pastoral region of Afar, in eastern and central Ethiopia, to determine the distribution of brucellosis in small ruminants. Between December 2005 and June 2006, 1,568 serum samples were taken: 563 samples from sheep and 1,005 from goats. One hundred and forty-seven of these (9.4%) tested positive using the Rose Bengal plate test (RBPT), and 76 (4.8%) also tested positive by the complement fixation test (CFT). Brucellosis was detected in all five administrative zones of the region. The difference in prevalence (P) among the zones was not statistically significant (P > 0.05). The seroprevalence of Brucella infection was found to be 5.8% (n = 58) in goats and 3.2% (n = 18) in sheep. A prevalence rate of 5.3% was observed in adult animals and 1.6% in younger sheep and goats. Caprine species (chi2 = 5.56) and adult goats and sheep (chi2 = 4.84) were found to be at higher risk of Brucella infection (P < 0.05). No statistically significant difference was found between males and females (chi2 = 2.57, P > 0.05). The study showed that small-ruminant brucellosis is a widely distributed disease in Afar. The authors recommend the implementation of well-organised disease control and prevention methods to mitigate the economic losses and public health hazard caused by the disease.     

Epidemiological and clinical aspects of human Brucella suis infection in Polynesia

High brucellosis seroprevalence rates in domestic swine herds have been reported in Wallis and Futuna Islands and are associated with a significant burden of human infection by Brucella suis, a species that is rarely incriminated in human disease. Between 2003 and 2010, seven patients had a positive blood culture for B. suis biovar 1, 11 symptomatic patients had a positive Rose Bengal test (RBT) and a positive serum agglutination test (SAT) and three asymptomatic cases were found to be positive for RBT, SAT or ELISA IgM (after systematic screening of 52 family members of 15 index cases). Overall, Brucella infection was diagnosed in 21 people, corresponding to a mean annual incidence of 19 cases/100 000 inhabitants. Compared to series of patients infected with other more commonly encountered Brucella spp. such as B. melitensis and B. abortus, clinical presentation and percentage and distribution of complications were similar, apart from a marked observation of significantly increased median alanine aminotransferase levels, 20 times greater than upper normal rates, but not accompanied by any particular hepatic pathology. Wallis and Futuna, where people live in close proximity to animals and where the cultural significance of pig-raising precludes the implementation of adequate veterinary preventive measures, thus represents one of the few known B. suis foci worldwide and allows for evaluation of the peculiarities of this infection.     

Immunological responses and protective efficacy against Brucella melitensis induced by bp26 and omp31 B. melitensis Rev.1 deletion mutants in sheep

The commonly used live attenuated vaccine in ovine brucellosis prophylaxis is Brucella melitensis Rev.1. This vaccine is known to induce antibody responses in vaccinated animals indistinguishable by the current conventional serological tests from those observed in challenged animals. Brucella BP26 and Omp31 proteins have shown an interesting potential as diagnostic antigens for ovine brucellosis. Accordingly, the bp26 gene and both bp26 and omp31 genes have been deleted from the vaccine strain Rev.1. Immunogenicity and vaccine efficacy of the parental Rev.1 strain and of both mutants in protecting sheep against B. melitensis strain H38 challenge was evaluated by clinical and bacteriological examination of ewes. They were conjunctivally or subcutaneously vaccinated when 4 months old and then challenged with B. melitensis H38 at the middle of the first pregnancy following vaccination. Deletion of bp26 and omp31 genes did not significantly affect the well recognised capacity of Rev.1 to protect sheep against B. melitensis challenge. However, the protection conferred by the CGV2631 mutant was significantly lower than that conferred by the CGV26 mutant or the Rev.1 strain. Vaccinated and challenged animals were detected positive in classical serological tests and in the IFN-gamma assay. A BP26-based ELISA was investigated to discriminate between ewes vaccinated by the mutants and ewes challenged with B. melitensis H38. The cut-off which was chosen in order to have 100% specificity resulted in a moderate sensitivity for the detection of challenged ewes. The use in the field of one of the mutants as vaccine against a B. melitensis infection, combined with classic diagnostic tests and a BP26 ELISA, could thus give an improvement in the differentiation between vaccinated and infected animals and contribute to the objective of eradication of brucellosis in small ruminants.     

Non-imported brucellosis outbreak from unpasteurized raw milk in Moroccan immigrants in Spain

Nine cases of brucellosis were identified in the city of Elche (Comunidad Valenciana, Spain) in two families of Moroccan immigrants. All of the patients had drunk unpasteurized raw milk from goats. Brucella melitensis biovar 3 was identified in clinical specimens. Preventive measures for brucellosis should be implemented among immigrant populations in Spain.     

应用羧化胶乳凝集试验诊断人、畜布鲁氏菌病的研究

应用以化学交联法制备的布鲁氏菌１６Ｍ抗原－羧化胶乳制剂的羧化胶乳凝集试验（ＬＡＴ）、试管凝集试验（ＳＡＴ）、虎红平板凝集试验（ＲＢＰＴ）以及酶联免疫吸附试验（ＥＬＩＳＡ）、半胱氨酸凝集试验（ＣＹＴ），对在四省布鲁氏菌病疫区收集的部分人、畜血清中布氏菌抗体进行对比检测。结果表明，ＬＡＴ较之ＲＢＰＴ具有更高的特异性；与ＳＡＴ相比，无论阳性或阴性符合率均较一致。另外，ＬＡＴ可检测血清中ＩｇＧ、ＩｇＭ两类布氏菌特异性抗体。因而本试验对人、畜布病的诊断具有特异、敏感和简便的优点，更宜在基层推广应用。