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The aim of this study was to evaluate the clinical, laboratory findings and therapeutic features of patients with brucellosis. The diagnosis was made by clinical findings, automated blood culture, serology (Rose Bengal plate agglutination test, standard tube agglutination (Wright) and immunofluorerescence). The susceptibility of 13 strains was tested in vitro. The base sequence was determined for four strains. Forty-five cases were collected (31 acute and 14 sub-acute). Contamination was digestive in 62%. Symptoms of patients were fever (93%), sweating (82%), arthralgia (78%) and splenomegaly (51%). Elevated erythrocyte sedimentation rate was determined in 80%, leukopenia in 49% and anaemia in 37% of cases. Blood cultures were positives in 39% of cases. The four sequenced strains were identified as Brucella melitensis biovar abortus. Six strains were resistant to sufomethoxazol-trimetoprim (54%). In 93% of cases, the treatment was associated rifampicin and doxycyclin. One patient died. No relapse was reported.

Brucella abortus is a facultative intracellular Gram negative bacterial pathogen that infects humans and animals by entry through the digestive tract. The immunogenic B. abortus ribosomal protein L7/L12 is a promising candidate antigen for the development of live oral vaccines against brucellosis, using food-grade lactic acid bacteria (LAB) as carrier. L7/L12 was produced under cytoplasmic and secreted forms [fused with a lactococcal signal peptide (SP)] in Lactococcus lactis, the model LAB. To express the L7/L12 gene, two promoters were used: i) the lactococcal constitutive promoter (P59) and ii) the nisininducible promoter (PnisA). Both P59 and PnisA leaded to an equivalent rate of production of both cytoplasmic (~ 0.5 mg/L) and secreted L7/L12 (⊬ 3 mg/L). The highest secretion efficiency (proportion of the secreted L7/L12) was 77% obtained with P59 compared to 35% observed with PnisA. With both promoters, a 6-fold increase of the level of L7/L12 production was observed after fusion with the SP suggesting a strong intracellular proteolysis of L7/L12. These lactococcal strains constitute a promising alternative vaccinal strategy against brucellosis., Brucella abortus est une bactérie pathogène à Gram négatif qui infecte le tube digestif de l'homme et des animaux. Nous développons des souches vaccinales de Lactococcus lactis contre la brucellose. L'antigène choisi est la protéine ribosomique L7/L12 de B. abortus. Nous avons produit L7/L12 sous forme cytoplasmique et sous forme sécrétée (après fusion avec un peptide signal). Chacune des formes a été exprimée sous la dépendance d'un promoteur constitutif (P59) et d'un promoteur inductible à la nisine (PnisA). L'utilisation de ces deux promoteurs conduit à des niveaux de production de L7/L12 équivalents : environ 0,5 mg/L pour la forme cytoplasmique et 3 mg/L pour la forme sécrétée. Dans les deux cas, on note une augmentation d'un facteur 6 du niveau de production de la forme sécrétée suggérant une protéolyse intracellulaire importante de L7/L12. Ces souches de lactocoques productrices de L7/L12, en cours d'essai chez la souris, constituent de nouvelles alternatives vaccinales contre la brucellose.

Four herds of zebus from northern Cameroon totalling 136 animals were vaccinated subcutaneously with the following doses of Brucella abortus strain 19: 5 x 10(9) colony-forming units (CFU), 10(9) CFU, 5 x 10(8) CFU and 10(7) CFU. Twenty-eight days after vaccination, the following seroconversion rates were observed respectively: 97.4, 96.2 84.2 and 73.3%. Of the 52 animals which could be tested subsequently including 39 over one year old on the vaccination day, only one showed antibodies 6 months after vaccination. The cost price of the strain 19 vaccine produced at the Boklé National Veterinary Laboratory was estimated to be 65 F CFA at the 10(9) CFU dose and 1,740 F CFA at the 5 x 10(10) CFU dose usually recommended. The use of the Buck 19 strain in the medical prophylaxis of bovine brucellosis in northern Cameroon is discussed.

Quatre troupeaux de zébus du nord-Cameroun, comprenant en tout 136 animaux, ont été vaccinés par voie sous-cutanée avec les doses suivantes de la souche B19 : 5 x 10 puissance 9 unités formant colonies (UFC), 10 puissance 9 UFC, 5 x 10 puissance 8 UFC et 10 puissance 7 UFC. Vingt-huit jours après la vaccination, les taux de séroconversion ont été respectivement les suivants : 97,4, 96,2, 84,2 et 73,3 %. Sur les 52 animaux, dont 39 âgés de plus d'un an le jour de la vaccination, ayant pu faire l'objet d'un contrôle sérologique ultérieur, 1 seul présentait des anticorps 6 mois après la vaccination. A la dose de 10 puissance 9 UFC, le coût de revient du vaccin B19 produit au Laboratoire national vétérinaire de Boklé est de 65 F CFA la dose ; à la dose habituellement préconisée de 5x10 puissance 10 UFC, il est de 1740 F CFA. Les différentes perspectives d'utilisation de la souche B19 dans la prophylaxie médicale contre la brucellose bovine au nord-Cameroun sont discutées.

The authors report the results of an epidemiological survey of bovine brucellosis in Mali, based on a relatively representative sample of 1,000 serum samples from 236 herds. The prevalence of infection in the herds, established by indirect enzyme-linked immunosorbent assay (ELISA) was 53% +/- 6.4. The proportion of animals infected was 23.3% +/- 2.5, falling to 22% when compared with the basic serum pool of 9,466 samples. This rate was relatively high in stationary herds in the semi-arid, sub-humid and arid zones. Four strains of Brucella abortus were isolated from cattle bearing hygromas.

For the evaluation of immunological tests during an epidemiological survey and of vaccination with the PI brucellin vaccine, in an occupationally exposed environment, a sample group of 354 subjects was studied. The vaccinal strategy was based on the outcome of a skin test for hypersensitivity: the PS brucellin test. In this framework, the serological status and evolution of individuals with positive or negative reactions to this test were analysed. Sera were studied using the buffered antigen test, indirect fluorescence immunoassay and Wright's agglutination test, as well as by PACIA and ELISA techniques with assay of IgG, IgA and IgM antibodies. The PS test, which was pivotal in this study, was compared with the lymphoblastic transformation test. One prominent aspect of this evaluation was the establishment of conventional prognostic indices for the PS and serology. The PS is definitely shown to be a convenient, reliable tool for screening. Although it does not generate sensitivity it may modify the serological status of both positive and negative individuals.

This prospective phase IV study on cohort concerns a vaccine made of the phenol-insoluble fraction of Brucella abortus biotype 1 (B19 strain). Three hundred and three professionally exposed subjects entered the study; 161 out of 182 subjects (88.5 percent) with negative response to an intradermal test for detection of previous contamination accepted to be vaccinated. Booster injections were given 18 and 36 months after vaccination. Local pain was observed after 45.2 percent of injections and moderate systemic reactions after 5 percent of injections. Seropositivity after primary vaccination reached 80 percent. The booster injection, justified by a major decrease of this rate after 18 months, gave exactly the same response of the thymo-independent type. This vaccinal schedule did not result in detectable hypersensitivity. The clinical effectiveness of the vaccine could not be evaluated accurately because of the insufficient number of subjects. The possibility of subclinical infection in vaccinated subjects calls for wider comparative studies of vaccinated versus non-vaccinated subjects.

Ce dernier article de la série sur la brucellose bovine en Afrique Centrale présente les résultats obtenus dans l'identification et le biotypage des souches isolées au Tchad et au Cameroun. Si la majorité des isolements est constituée par Brucella abortus biotype 3 (67 p. 100), l'homogénéité relevée par d'autres chercheurs n'est pas entièrement confirmée: 3 p. 100 des souches sont des Brucella melitensis biotype 1, 1 p. 100 des Brucella abortus biotype 2, 15 p. 100 des Brucella abortus biotype 6 et 14 p. 100 des Brucella abortus biotype intermédiaire 3/6. La diversification des échantillons pathologiques analysés devrait clarifier ce point car, jusqu'à ce jour, l'essentiel des prélèvements est constitué par les liquides d'hygromas du genou, lésions fréquentes et faciles à repérer dans les troupeaux africains. Les caractères biochimiques correspondent assez bien aux normes classiques des espèces de Brucella, avec, en particulier, une épreuve de l'oxydase positive pour 94 p. 100 des souches. Bien que peu de souches aient fait l'objet d'une étude du métabolisme oxydatif, on note un profil voisin de celui de Brucella abortus. Cependant, l'utilisation de certains substrats rapproche une partie des souches centrafricaines analysées du profil habituel de Brucella suis.

Carbohydrates localization on ultrathin sections of Brucella abortus, melitensis and Excherichia coli cells has been studied by the periodic acid thiocarbohydrazide-silver proteinate (PATAg) and phosphotungstic acid (PTA) methods. Carbohydrates are mainly localized on the cell envelope of Brucella and Escherichia but there are several differences between these two bacteria. The differences are discussed and a Brucella polysaccharide envelope model is proposed. The PATAg method gives the same silver grain deposits on Brucella S and R and Escherichia S and R. The phosphotungstic acid method differenciates Brucella S and R cells by lack of contrast on the outer leaflet of the outer membrane of the latter, but does not differenciate E. coli S or R cells. The Brucella outer membrane contains less polysaccharides than that of E. coli. There is a seemingly symetric distribution of polysaccharide in the Brucella outer membrane as compared to an asymetric distribution in E. coli. The peptidoglycan of Brucella reacts strongly as compared with that of E. coli. The polysaccharides present a dispersed pattern in Brucella cytoplasm, whereas in E. coli they appear as dense, strongly reactive clusters very close to the cytoplasmic membrane.

The results obtained with Brucella B19 strain, used as adjuvant and stimulant in the preparation of hyperimmune anti-foot-and-mouth disease serums on guinea pigs, have led the authors to carry out a series of experiments with a combined anti-foot-and-mouth disease and anti-brucellosis vaccine (strain B 19 Buck and Cotton). The search for neutralizing antibodies for foot-and-mouth disease has been undertaken by different methods. In the search for antibrucellic antibodies reactions such as seroagglutination, fixation of the complement, etc. have been used. The results obtained with combined vaccine are identical with those obtained with each of the monovalent vaccines.

Medical and sanitary prevention of a growing number of major infectious diseases of bovines has led IFFA-Mérieux to investigate the association of vaccines and to define methods of utilization. Care has been taken to limit the number of interventions and at the same time to retain in the combined valences the efficacy they had when in a state of single constituent. The work which has been carried out for the last ten years, including the study of adjuvants as well as of incompatibility of associations, has permitted the improvement of formulas, reduced in volume (5 ml for a plurivalent dose), in aqueous excipient (aluminum hydroxide and saponin) or oily excipient (oil in water type). These formulas combine 3 foot-and-mouth disease valences with a rabies valence (fixed strain grown on cell culture) or with a brucellosis valence (strain B. abortus MacEwen 45/20 and B. melitensis H 38). The innocuity of these associations allows them to be used in sanitary compaigns; their efficacy is equal to that of monovalent vaccines. A logical vaccination calendar is proposed.

Immune serum and spleen cells from mice vaccinated with a cell-wall fraction (PG) from Brucella were previously shown to transfer a good protection to mice against a virulent Brucella challenge. This protection estimated by spleen and liver time-course infection was similar to that afforded by vaccination. In present experiments, DBA/2 mice were first transferred with either immune serum from infected mice, splenic cells from mice intravenously vaccinated with PG fraction 28 days previously, or both immune serum and splenic cells. In this case, the serum was either injected before the challenge, as were the splenic cells, or 2 days after it in order to reduce the lowering effect of the serum on level of initial colonization of the spleen. The transferred mice were then intravenously challenged with the virulent strain B. abortus 544 and liver and spleen counts were performed on groups of five mice weekly up to six weeks. Immune serum and splenic cells from vaccinated mice were again shown to strongly reduce the time-course of splenic infection. However addition of both effects was observed for a short time only two and three weeks post-challenge and only when the serum was injected after the challenge. In contrast, no additive or even an antagonistic effect was observed after the 21st day. Liver infection was not notably modified by both immune serum or splenic cells (except increment of initial colonisation by serum) until the 21st day when both helped reduce the course of infection. However again no additive effect was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Within the framework of a study on the immunostimulant properties of Brucella abortus and of its extracts, we have investigated the protective activity on infection of mice by Klebsiella pneumoniae and on Charlotte Friend's leukemia, of inactivated Brucella abortus and brucella lysates by ultrasound. The injection of inactivated B 19 R preparations and their lysates three days before infection by klebsiella has allowed to protect mice against a large number of DL50 (100 and 1000 in certain cases). To determine the role of the surface antigen in this type of immunostimulant, the activity of the B 19 R inactivated preparations has also been examined. It appears that the protection obtained by the injection on day J + 3, in relation to the infection, does not depend on the presence of the complete surface antigen, while the long term effect seems to be more dependent on this. The development of Charlotte Friend's leukemia has been favourably influenced by the previous injection of B 19 S or inactivated B 19 R. Immunotherapy on days J + 1 or J + 3 gave encouraging results with B 19 R, but facilitation with B 19 S. These results confirm the immunostimulant activity of brucella which has already been reported by ourselves and by other authors.

We report the case of a 36-year old male patient who was admitted for subacute endocarditis on an aortic prosthetic valve implanted 14 years previously for endocarditic valve regurgitation; no pathogen had been isolated at that time. Nine blood cultures were positive for Brucella abortus. The conventional antibiotic therapy did not prevent the formation of an abscess below the aortic annulus. A third antibiotic combination (quinolone and rifampicin) resulted in pyrexia prior to surgery. An atrioventricular block initially noted raised the problem of an associated myocarditis. The risk of Brucella infection existed before the first operation, and five serological tests were positive for that organism between the two episodes, which makes reinfection highly probable. This is the third case of Brucella endocarditis on a prosthetic valve. Its originality lies in its mechanism.

Passive hemagglutination test (HP) after binding of ABS antigen to SRBC by chromium chloride, lymphocyte transformation (TTL) and inhibition of leukocyte migration (TML) tests were compared to tube agglutination and complement fixation tests, and to clinical symptoms for diagnosis of brucellosis. Both TTL and TML persist for years after contact with brucella. HP is the most reliable serologic test.

Coupling of an extract from B. abortus strain 99 to sheep red blood cells by chromium chloride allowed to develop a highly specific and reliable passive hemagglutination test (H). Indeed, H was positive in 99.8 per cent sera from 968 known Brucella-infected heifers, while tube agglutination revealed only 59 per cent and complement fixation 90.9 per cent positive cases. H was positive in 153 sera from 778 proven or suspected human brucellosis where agglutination and/or complement fixation tests were positive, and in 21 sera negative to conventional tests. H demonstreated remote or undiagnosed human B. abortus infections in 28.6 per cent of 18 367 human sera randomly examined in a rural area. Therefore, a simple easy-to-perform passive hemagglutination test could replace a battery of conventional tests for the diagnosis of individual brucellosis, and epidemiologic surveys. The present study points to a high prevalence of undiagnosed brucellosis in man, specially in those area where cattle are raised.

Two hundred and eight strains of Brucella isolated from cattle and 5 isolated from man in various areas of France, during a two-year period from 1972 to 1974, were examined by all methods recommended by the Subcommittee on Taxonomy of the genus Brucella and were found to have the same characteristics that identify and define the species Brucella abortus. Of the 213 strains, 105 (49,29 p. 100) were biotype I, 103 strains (48,36 p. 100) biotype 3, three strains (1,41 p. 100) biotype 4 and 2 strains (0,94 p. 100) biotype 2. The distribution of Brucella abortus biotypes isolated from cattle and man in France is reviewed and compared with the data from our sample. It corroborates the epidemiologic importance of Brucella abortus biotype 3, just after type 1, and the absence of biotypes 5 to 9(1) in France. Five strains of Brucella abortus biotype 3, originating from a well-defined geographical area, are ureaseless. This new biochemical character distinguishes these strains from the main group of biotype 3 and is discussed from an epidemiological and methodological point of view. Data on the oxydative rates obtained on 12 substrates by the 213 strains are presented in graphic form which reveals a metabolic profile for the species Brucella abortus. The interest of this graphic presentation is discussed and its use should be recommended.

While a brucellosis disease proved with bacteriological and serological tests, a serodiagnostic of amebiasis using the immunofluorescence techniques has been positive toward a dilution of 1/320. The authors think to have a false positive reaction in amebiasis. Even though the anatomopathological examination of the liver did not show any amoebiasis focus, we can see some histological lesions due to a present or an old brucellosis disease.

With the aim of knowing more exactly what species and biotypes are responsible for brucellosis in France, 2,058 strains have been examined since 1972. Of these, 1,693 were isolated from cattle, 190 from sheep, 10 from hare, 9 from goats, 3 from swine and 3 from field mice (Apodemus sylvaticus); 150 were of cases of human infection. Of the 18 types presently recognized for the genus Brucella, 11 were identified within the sample. In animal strains, they were B. abortus biotypes 1, 2, 3, 4 and 9, B. suis biotypes 1 and 2, B. melitensis biotypes 1, 2 and 3, and B. ovis. All these types--except B. suis 2 and B. ovis--were identified within the human strains. Of these 11 types, 3 were widely predominant both in man and animals: B. abortus biotypes 1 and 3 and B. melitensis biotype 3, which together total 84.2% of the sample's strains. The results also emphasized the preference of B. abortus, B. melitensis and B. ovis for a decided animal host: 99.4% of the bovine strains were B. abortus, 98.1% of those isolated from ewes and goats were B. melitensis, and all the B ovis strains were from cases of ram epididymitis. Of the 150 human strains, 115 were B. melitensis, 33 B. abortus and 2 B. suis. These data were discussed from a taxonomical and epidemiological point of view.

Forty-five brucella infected cows were studied 15 to 30 days following abortion. Eighteen cows were slaughtered and autopsied for examination of Brucella in the organs and lymph nodes. The remaining 27 cows were treated during two and one-half months and then slaughtered after undergoing a treatment with 0, 1, 2 or 3 intraperitoneal injections of oxytetracycline dissolved in 100 ml of physiological saline. The treatment modified only slightly the natural evolution of antibody titers. The levels of infection were similar for all cows which received no treatment. Cows treated with oxytetracycline had less severe infection than the non treated animals and four were infection-free at slaughter. The level of infection of treated cows was independant of the treatment regime. The advantages of treating non pregnant cows to reduce the level of infection and risk of abortion were discussed.

Sera from 30 sheep experimentally infected and from 126 others with chronic brucellosis were comparatively studied by serum agglutination (SA), complement fixation (CF), rose bengal (RB), and counter-immunoelectrophoresis (CIEP) test. Standard serological tests, particularly SA and RB, essentially detect antibodies against cell-wall fractions of Brucella (LPS), whereas CIEP responds to intracellular antigens. Antibodies involved in this test appear late but remain a long time in the sera. CIEP is therefore recommended for screening of animals with chronic brucellosis in which SA and often CF and RB tests too negative.