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F Grimont

Publications and source records attributed to F Grimont.

At least 55 records · Page 3Linked to original sources
PubMed1996

Large outbreak of Salmonella enterica serotype paratyphi B infection caused by a goats' milk cheese, France, 1993: a case finding and epidemiological study.

OBJECTIVE: To assess the magnitude of a nationwide outbreak of infection with Salmonella enterica serotype paratyphi B and identify the vehicle and source of infection. DESIGN: A case finding study of S paratyphi B infection between 15 August and 30 November 1993; a pair matched case-control study; an environmental investigation at a processing plant that produced a raw goats' milk cheese incriminated in the outbreak; phage typing and genotyping of food and human S paratyphi B isolates. SETTING: France, 15 August to 30 November 1993. SUBJECTS: 273 patients with S paratyphi B infection; 59 pairs of cases and controls matched for age, sex, and city of residence. MAIN OUTCOME MEASURES: Numbers of cases and incidence rates by region of residence and age; matched odds ratios for dairy food preferences. RESULTS: Among the 273 cases there was one death; 203 (78%) strains belonged to phage type 1 var 3. The incidence of infection was greatest in the region where goats' milk cheese is commonly produced. Comparison of cases and controls showed a 12-fold greater risk of illness (95% confidence interval 1.6 to 92.3) from eating brand A unpasteurised goats' milk cheese. S paratyphi B isolates of phage type 1 var 3 were recovered from cheese A, goats' milk at the plant processing cheese A, and goats' milk supplied to the plant by a single farm. Genotypic IS 200 typing of food and human 1 var 3 phage type isolates showed a common IS 200 pattern. CONCLUSION: This outbreak emphasises the potential health hazards of widely distributed unpasteurised milk products in France and the need for their close bacterial monitoring.

Adolescent↗
PubMed1996

Cluster of cases of haemolytic uraemic syndrome due to unpasteurised cheese.

A cluster of four patients (1 girl, 3 boys) from a French village (2,000 inhabitants) had acute haemolytic uraemic syndrome (HUS) between March 1992 and May 1993. All had prodromes with fever and diarrhoea, then acute renal failure, anaemia, schistocytosis and thrombocytopenia. Peritoneal dialysis was carried out in three children (duration 3-12 days). The verotoxin VT2 gene was identified by polymerase chain reaction in the stools of two children. Some days prior to the diarrhoea, all children had eaten a cheese made with unpasteurised mixed cows' and goats' milk from the same farm. A case control study showed that the occurrence of HUS was linked to the consumption of this milk product (P = 0.006). The VT 2 gene was isolated from the cheese and from the stools of goats and cows from the farm, but not from the stools of farm employees.

Acute Disease↗
PubMed1996

[Identification and typing of hospital strains of Acinetobacter calcoaceticus-Acinetobacter baumanni complex].

A collection of 95 strains of the Acinetobacter calcoaceticus-Acinetobacter baumannii complex, isolated between 1991 and 1993 in the Prague Burn Center (BC), was studied. Ninety-one strains were isolated from 43 patients: 50 of them from burnt sites, 22 from endotracheal tube, 13 from urine, 3 from blood and 3 from venous catheter, and 4 strains were isolated from the hospital environment and the nursing staff. The strains were classified by restriction endonuclease fingerprinting of total DNA, plasmid profile analysis, ribotyping, comparison of antibiograms, biotyping and according to epidemiological data, into 31 relatedness groups each of them including 1 to 29 strains, likely to be isolates of the same strain. None of the methods used enabled to distinguish all groups. The importance of the polyphasic approach is emphasized since three multiresistant strains, isolated almost simultaneously in the BC, needed at least two methods to be distinguished (e.g. ribotyping and biotyping). Twenty-eight representative strains of different groups were identified by ribotyping: 18 of them were allocated to genomospecies 2 (A. baumannii), 5 to genomospecies 3 and 5 to genomospecies 13 sensu Tjernberg and Ursing. Only A. baumannii was found to spread among patients. Strains of two multiresistant groups persisted in the BC throughout the period studied and strains of one of these groups were responsible for an outbreak in the autumn of 1993. The methods mentioned above were used to describe 12 multiresistant strains isolated in three hospital wards in other localities. When ribotyped these strains were identified as A. baumannii. The strains of the same origin were identical in their typing profiles while the strains of different origins were easy to differentiate using any of the above methods; nevertheless, 2 of these groups were almost identical to 2 groups of multiresistant strains isolated in the BC.

Acinetobacter↗
PubMed1995

Acinetobacter baumannii outbreak isolates characterized by three typing methods.

Forty-two strains of Acinetobacter baumannii were isolated from 15 patients hospitalized in a French intensive care unit. An epidemiological study based on the typing of these isolates was carried out using biotyping, antibiotyping, and ribotyping to recognize the transmission of multiresistant strains by transfer of a patient from one hospital to another. Fifteen strains from the outbreak (1 strain for each patient), five Acinetobacter baumannii strains isolated before the outbreak in Bellevue Hospital (St. Etienne), and five strains isolated in Cochin Hospital (Paris) were included. The three methods gave a good correlation: the epidemic strains had the same antibiotic resistance pattern, the same biotype, and the same ribotypes obtained with three different endonucleases.

Acinetobacter↗
PubMed1994

Replicon typing of 71 multiresistant Serratia marcescens strains.

Replicon typing is the identification of plasmids by hybridization with specific DNA probes which contain the genes involved in plasmid maintenance. This new method has been used to classify plasmids into replicon (rep) groups which can often be correlated with incompatibility (Inc) groups. We studied 71 multiresistant Serratia marcescens strains with 19 rep probes constructed from reference plasmid replicons belonging to known Inc groups. These probes are known to react with enteric bacterial plasmids. However, they did not represent the totality of the thirty known Inc groups. For 52% of the studied strains, plasmids were identified and classified into groups FIB, FIC, FIIA, HI2, L/M, N, B/O, P, W, Y and Com9. Most (79%) of the plasmid preparations hybridized with a single rep probe, and 21% hybridized with two different probes. Electrophoretic analysis of DNA suggested that double hybridization could result from the presence of either two different Inc plasmids in the same strain (e.g. S37) or one single plasmid with a multireplicon (e.g. S113).

Bacterial Typing Techniques↗
PubMed1994

Plague pandemics investigated by ribotyping of Yersinia pestis strains.

Yersinia pestis is the causative agent of plague, a disease which has caused the deaths of millions of people and which persists now in endemic foci. The rRNA gene restriction patterns (i.e., ribotypes) of 70 strains of Y. pestis, isolated on the five continents over a period of 72 years, were determined by hybridization with a 16S-23S rRNA probe from Escherichia coli. The combination of the EcoRI and EcoRV patterns resulted in the elucidation of 16 ribotypes. Two of them (B and O) characterized 65.7% of the strains studied, while the 14 other ribotypes were found in no more than three strains each. A relationship was established between biovars and ribotypes: strains of biovar Orientalis were of ribotypes A to G, those of biovar Antiqua were of ribotypes F to O, and those of biovar Medievalis were of ribotypes O and P. Great heterogeneity in rRNA restriction patterns was found among strains isolated in Africa; this heterogeneity was less pronounced among Asian isolates and was completely absent from the American strains. Pulsed-field gel electrophoresis was performed on the DNAs of some strains, but it appeared that different colonies from the same strain displayed different pulsed-field gel electrophoresis patterns and therefore that this technique was not suitable for comparison of Y. pestis isolates. In contrast, the ribotypes of individual colonies within a given strain were stable and were not modified after five passages in vivo. A clear correlation between the history of the three plague pandemics and the ribotypes of the strains could be established.

Bacterial Typing Techniques↗
PubMed1994

Restricted association between biotypes and serotypes within group A streptococci.

Investigating individual variations between different isolates of group A streptococci, we observed a close correlation between biotypes and serotypes in 46 strains from pharyngitis patients. Biotyping, carried out with a commercially available rapid identification gallery, delineated 10 different associations of characteristics, designated biotypes 1 to 10, observed both in the manufacturer's (127 strains) and our personal (98 strains) collections of group A strains. Only the most frequent biotypes (biotypes 1 to 6) were observed in the pharyngitis cohort, but the overall frequencies of the biotypes did not display striking differences compared with the control collections. Serotyping of the pharyngitis strains showed that each M type was restricted to a sole biotype. For example, M types 1, 4, and 28 were found only in biotype 1 and M type 6 was found only in biotype 6 strains. This association was not due to an epidemiologic bias, since it was also observed in a control series consisting of reference strains and isolates from distant countries (the United States and Czech Republic versus France). An exception was for M type 78, which exhibited biotype 3 or biotype 4. Investigation of the heterogeneity of the strains at the DNA level showed no significant variations of the ribotype patterns between strains of different biotypes, confirming that group A streptococci belong to a unique and homogeneous species. This previously undescribed association between serotypes and biotypes is of interest for a rapid and preliminary characterization of strains isolated in individual patients or during an outbreak. A possible pathogenic association of some biotypic characteristics with specific M proteins is envisaged.

Adolescent↗
PubMed1993

Enterobacter cloacae cross-colonization in neonates demonstrated by ribotyping.

The intestinal colonization by Enterobacter cloacae strains with a derepressed cephalosporinase was studied in a paediatric ward between February 1990 and January 1991. Environmental sampling was performed simultaneously. Fifty-two isolates were recovered from 200 neonates (stool, blood) and 14 strains were isolated from the neonatal environment. An epidemiological study based on the typing of 36 Enterobacter cloacae isolates was carried out using antibiotyping, biotyping and ribotyping methods. The isolates selected were from 21 neonates (24 isolates), the neonatal ward environment (8 isolates) and from other wards (4 isolates). Thirty-two isolates had the same antibiotic resistance pattern, corresponding to a derepressed cephalosporinase and resistance to the following aminoglycosides: kanamycin, gentamicin, tobramycin and netilmicin. No predominant biotyping pattern could be established. Ribotyping done with two endonucleases (EcoRI and BamHI) showed 28 Enterobacter cloacae isolates to have a single pattern. Ribotyping was the most discriminating method used in this study, permitting identification of cross-contamination with Enterobacter cloacae in the paediatric ward.

Bacteremia↗
PubMed1993

Molecular typing of Chlamydia trachomatis by random amplification of polymorphic DNA.

The random amplification of polymorphic DNA (RAPD) was used for epidemiological typing of Chlamydia trachomatis strains. DNA samples from 39 C. trachomatis, 1 C. pneumoniae and 2 C. psittaci strains were screened by the use of 4 single 10-mer primers. Different and reproducible banding profiles were observed on agarose gel electrophoresis. No common profiles were recorded for strains from different Chlamydia species. All C. trachomatis strains of trachoma biovar were distinguished from lymphogranuloma venereum biovar. Moreover, serotypes A to C were separated from serotypes D to K, and some groups of strains sharing the same serotype D to K were further subdivided by RAPD. Conversely, strains of different serotypes could produce identical patterns of amplification, indicating that RAPD did not reflect serotyping. The patterns of amplified products were compared to the restriction fragment length polymorphism of the omp1 gene after amplification and to DNA fingerprinting by use of ribosomal RNA or randomly cloned DNA probes. RAPD seemed to be an alternative molecular typing procedure for epidemiological study and strain identification in urogenital infections due to serotypes D to K.

Chlamydia trachomatis↗
PubMed1993

Balneatrix alpica gen. nov., sp. nov., a bacterium associated with pneumonia and meningitis in a spa therapy center.

In 1987, an outbreak of pneumonia and meningitis caused by an unknown bacterium occurred in a spa therapy centre. Nine isolates of this pathogen constituted a tight DNA hybridization group. rRNA-DNA hybridization and 16S rRNA sequencing showed that the studied bacteria represented a new branch in superfamily II (= gamma subclass) of the Proteobacteria, close to the genus Oceanospirillum. The new bacterium was highly polymorphic and, in young cultures, had curved Gram-negative cells, motile by polar single flagella. The new bacterium differed from the genus Oceanospirillum by its lacking the NaCl requirement and by reducing nitrate into nitrite, producing indole from tryptophan and producing acid from carbohydrates. The name Balneatrix alpica gen. nov., sp. nov. is proposed for the studied organism. The type strain is strain 4-87 (= CIP 103589).

Balneology↗
PubMed1993

Relatedness of three species of "false neisseriae," Neisseria caviae, Neisseria cuniculi, and Neisseria ovis, by DNA-DNA hybridizations and fatty acid analysis.

DNA-DNA hybridization was used to determine the levels of genomic relatedness of the three species of "false neisseriae," Neisseria caviae, Neisseria cuniculi, and Neisseria ovis. The reference strains of these species exhibited high levels of intraspecies relatedness (93 to 100% for N. caviae, 79 to 100% for N. cuniculi, and 68 to 100% for N. ovis) but low levels of interspecific relatedness (less than 34%) to each other and to various species belonging to the beta subclass of the Proteobacteria (Kingella kingae, Neisseria gonorrhoeae, Neisseria meningitidis, and Oligella urethralis) or to the gamma subclass (Branhamella catarrhalis, Kingella indologenes, Moraxella atlantae, Moraxella bovis, Moraxella lacunata subsp. lacunata, Moraxella lacunata subsp. liquefaciens, Moraxella nonliquefaciens, Moraxella osloensis, and Moraxella phenylpyruvica). However, the levels of DNA-DNA hybridization for the three species of "false neisseriae" were significantly higher with the species belonging to the gamma subclass (average, 13.7%) than with the species belonging to the beta subclass (average, 4.5%). These data suggest that N. caviae, N. cuniculi, and N. ovis are three separate genomic species in the gamma subclass. An ascendant hierarchical classification based only on fatty acid profiles distinguished four main classes containing (i) most of the "classical moraxellae," the "false neisseriae," and B. catarrhalis, (ii) only Acinetobacter spp., (iii) M. nonliquefaciens and "misnamed moraxellae" (M. atlantae, M. osloensis, and M. phenylpyruvica), and (iv) the "true neisseriae," the three Kingella species, and O. urethralis. Fatty acids that distinguish these four classes were identified. The fatty acid profiles of the two strains of Psychrobacter immobilis which we studied are not very similar to the profiles of the other taxa. Our results support the hypothesis that the three species of "false neisseriae," B. catarrhalis, the "classical moraxellae," and Acinetobacter spp. should be included in the same family.

Bacterial Typing Techniques↗
PubMed1993

Staphylococcus pasteuri sp. nov., isolated from human, animal, and food specimens.

A new novobiocin-susceptible species of the genus Staphylococcus, Staphylococcus pasteuri, is described on the basis of the results of a study of seven strains isolated from human, animal, and food specimens. DNA relatedness experiments (S1 nuclease method) showed that these strains form a homogeneous genomic species related at DNA homology levels of 2 to 13% to 27 type strains representing known Staphylococcus species. The use of a method based on rRNA gene restriction site polymorphism provides clear-cut distinction between this new species and Staphylococcus warneri, which is the most similar species phenotypically. The type strain of the new species is strain BM9357 (= ATCC 51129).

Amino Acids↗
PubMed1992

Molecular typing of Brucella with cloned DNA probes.

Brucella constitutes a single genomic species (B. melitensis); however, for epidemiological studies, methods are needed for discriminating strains within this genomic species. DNA samples from 112 Brucella strains were cleaved by restriction endonucleases and the fragments separated by agarose gel electrophoresis and transferred to nylon membranes. When the DNA fragments on the membranes were probed with 32P-labelled 16 + 23 S rRNA from Escherichia coli, a single rRNA gene restriction pattern was obtained after cleavage with all endonucleases tested (HindIII, EcoRI, SmaI, and XhoI) except BamHI. This indicated high genomic homogeneity within the single Brucella species. Of 30 probes consisting of random Brucella DNA fragments cloned into lambda EMBL3, 20 yielded a single BamHI restriction pattern per probe when applied to 112 Brucella DNA tested. However, 7 probes yielded 3 to 12 different patterns among DNA tested. These patterns more-or-less correlated with the classification of strains into biogroups (Melitensis, Abortus, Suis, Neotomae, Ovis and Canis) and biovars (18 biovars represented). Probe A was capable of separating biogroup Melitensis from the other biogroups. Probe C separated the set of biogroups Melitensis-Abortus-Ovis from the other biogroups. By reference to the patterns obtained using 1 to 7 probes, the most frequently occurring biovars (Melitensis 1, Melitensis 3, Abortus 1, Abortus 3, Suis 2 and Ovis) could be distinguished from each other. Eight biovars showed more than one pattern with 1 to 7 probes. The proposed typing system should be useful for epidemiological subtyping and does not pose safety problems once the DNA has been extracted.

Autoradiography↗
PubMed1992

Molecular typing of Salmonella enterica subsp. enterica serovar Wien by rRNA gene restriction patterns.

Analysis of digested DNA from 40 Salmonella enterica subsp. enterica serovar Wien isolates revealed five different rRNA gene restriction patterns for HindIII (H1 to H5) and five for PstI (P1 to P5). The isolates had been selected on the basis of the year of isolation, the geographic origin and the antibiotic resistance pattern and were distinguished as follows: a) 13 pre-epidemic isolates from different French towns in 1958-69 and from Senegal in 1968; b) 7 epidemic isolates from Algiers in 1969; c) 20 post-epidemic isolates from different French and Italian towns in 1970-90. Three different rRNA patterns (H1P1, H3P3 and H4P4) were observed among the pre-epidemic isolates. Conversely, the epidemic isolates, which were characterized by the previously described large antibiotic resistance patterns and by the presence of 1.3 and 80-109 MDa plasmids, belonged to the same H1P1 ribotype. All but two post-epidemic isolates were of the H1P1 ribotype. The determination of rRNA gene restriction patterns together with the plasmid content proved to be useful for a better characterization of the serovar Wien endemic and epidemic isolates.

Animals↗