广东伤寒菌株的Vi Ⅱ噬菌体型别与药物敏感性监测

对从广东省收集的72株伤寒杆菌进行Vi Ⅱ噬菌体分型及药物敏感性测定,结果表明能明确定型的为62株(86.1%)。噬菌体分型以M₁(41.9%)、E₁(30.6%)和A(19.4%)为常见菌型。72株地方株与国家参考标准株一样,对氯霉素、庆大霉素、新霉素和多粘菌素B 100%敏感,而对另14种常用抗菌药物,则有不同程度的敏感或耐药。今昔菌株药敏特性无大变化,氯霉素等仍可作为治疗常选药物。     

Salmonellosis in Indonesia: phage type distribution of Salmonella typhi.

The distribution of phage types was studied among 577 strains of Salmonella typhi from Indonesia. Chemotype, colicinogeny, and tetrathionate reductase activity were also studied for most of these strains. The current phage type formula for Java was determined to be: A, D2, D6, E1a, E2, M1, and 46, but two other large groups of strains were also found, I + IV and degraded Vi+ strains. Significant differences in S. typhi strain distributions were noted between two localities on Java with respect to phage type and tetrathionate reductase activity. Comparisons were made with past phage typing studies in Jakarta as well as with more recent studies in other parts of south-east Asia. Phage types A, D1, D2, and E1 persisted at a rather steady level in Jakarta for 28 years. Evidence was found for epidemiological links to European and Asian areas. Antibiotic resistance among these Indonesian S. typhi strains was rare.     

Subdivision of Salmonella enteritidis phage types by plasmid profile typing

Differentiation of Salmonella enteritidis by plasmid profile typing has been compared to differentiation by phage typing. Examination of the type strains of the 27 S. enteritidis phage types showed that only 11 profile patterns could be identified. Moreover, two profile patterns were found in 15 of the type strains, including those of the two most common phage types in Britain, types 4 and 8. On this basis, plasmid profile typing is not as sensitive as phage typing for the primary subdivision of S. enteritidis. When differentiation of 534 strains of the 27 phage types was attempted using plasmid profiles, variation in pattern suitable for epidemiological subdivision was found in 13 phage types and there were 9 profile patterns in strains of phage type 4. Plasmid profile typing can, therefore, be regarded as an effective adjunct to phage typing for the subdivision of S. enteritidis.     

rDNA fingerprinting as a tool in epidemiological analysis of Salmonella typhi infections.

Characterization of 169 strains of Salmonella typhi of phage types C1, C4, D1 and D9 isolated in 1975-88 was carried out by rDNA gene restriction pattern analysis. Twenty-four isolates had been recovered during four large waterbone outbreaks in the last 20 years in Sicily; 145 strains, isolated from apparently sporadic cases of infection in Southern Italy in the same period of time, were also examined. Application of rRNA-DNA hybridization technique after digestion of chromosomal DNA with Cla I showed the identity of patterns of the epidemic strains of phage types C1 and D1, confirming attribution of the outbreaks to single bacterial clones. Patterns of the two available strains of lysotype D9 were slightly different, whilst the 12 epidemic strains of phage type C4 could be assigned to two distinct patterns scarcely related to each other and, consequently, to two different clones. A considerable heterogeneity was detected among all apparently sporadic isolates of the four phage types under study. This fingerprinting method appears a reliable tool to complement phage typing in characterizing isolates of S. typhi. In particular, epidemiological features of spread of this salmonella serovar in areas, where simultaneous circulation of indigenous and imported strains occurs, can be elucidated.     

Genome fingerprinting of Salmonella typhi by pulsed-field gel electrophoresis for subtyping common phage types.

The genomic DNA of 39 strains of Salmonella typhi isolated from local residents and patients who had visited countries in the Asian region was analysed for restriction fragment length polymorphisms (RFLP). Pulsed-field gel electrophoretic (PFGE) analysis of Xba I- and Spe I-generated genomic restriction fragments established 22 PFGE types whereas phage typing differentiated the 39 isolates into 9 distinct phage types. This study showed that PFGE is more discriminatory than phage typing as it is capable of subtyping S. typhi strains of the same phage types. Genetic relatedness among the isolates was determined. Seven major clusters were identified at SABs of > 0.80 and the remaining 13 isolates were distributed into minor clusters which were related at SABs of less than 0.80. In conclusion, PFGE analysis in conjunction with distance matrix analysis served as a useful tool for delineating common S. typhi phage types of diverse origins from different geographical locales and separated in time.     

伤寒沙门菌Vi抗原作为毒力因子的特性研究

目的　探讨伤寒沙门菌Vi抗原作为毒力因子在致病机理中的作用。方法　选用Vi阳性和Vi阴性伤寒沙门菌作为实验菌株 ,体外考查了Vi抗原在抵抗渗透压 (NaCl)和过氧化物 (H2 O2 )中的作用 ,以及抵抗单核吞噬细胞内化和胞内杀伤的作用。结果　高浓度NaCl明显减少Vi阴性伤寒沙门菌的存活 ;低浓度的H2 O2 对Vi阴性伤寒沙门菌的存活有显著的影响 ;单核吞噬细胞内化和胞内杀伤伤寒沙门菌明显高于对照组。结论　伤寒沙门菌的Vi抗原作为一种毒力因子对其存活于体内及逃避机体的防御机理具有重要作用。     

Phage types of Salmonella typhi isolated in Malaysia over the 10-year period 1970-1979.

The pattern of phage types of 2553 strains of Salmonella typhi isolated over the 10-year period 1970-9 was studied. During the period 29 different phage types were encountered, not including the categories of ''untypable strains'', ''degraded Vi-strains'' and Vi negative strains. For the period as a whole, the commonest phage types encountered were A (20.9%), E1 (14.8%), D1 (10.3%), degraded Vi positive strains (10.3%), untypable Vi strains (7.3%), C4 (7.1%), D2 (4.4%), E2 (3.9%) and type 25 (2.6%). There were phage types which appeared in the early years of the period and then disappeared (types B2, D9 and D1-N). Others only made their appearance in recent years (K1 and 53). Notable differences were also seen in the predilection of some phage types for certain geographical areas.     

Characterization of verocytotoxin-producing Escherichia coli O157 isolates from patients with haemolytic uraemic syndrome in Western Europe.

Fifty verocytotoxin (VT)-producing Escherichia coli (VTEC) strains of serogroup O157 were characterized by phage typing, polymerase chain reaction (PCR) for VT genes and the E. coli attaching and effacing (eae) gene, and random amplified polymorphic DNA-PCR (RAPD-PCR) fingerprinting. The collection represented isolates obtained from patients with diarrhoea-associated haemolytic-uraemic syndrome (D+ HUS) and their family contacts, isolated in the Netherlands, Belgium and Germany between 1989 and 1993. Based on isolates from separate families (n = 27) seven different phage types were identified, types 2 (44%) and 4 (33%) were predominant. Eighty-five percent of the strains contained only VT2 gene sequences and 15% both VT1 and VT2. All strains of the dominant phage types 2 and 4 carried the VT2 gene. Strains that belonged to the minor phage types 8, 14, 32 carried both VT1 and VT2 genes, with the exception of two isolates identified as phage types 49 and 54 which contained only VT2 genes. All O157 VTEC strains possessed the chromosomally-located eae gene, which indicates its usefulness as virulence marker. RAPD-PCR fingerprinting identified four distinct banding patterns, with one profile found among 79% of the strains. Based on the combined results of all typing methods used in this study, the collection of 50 O157 VTEC strains could be divided into nine distinct groups. Strains isolated from different persons within one family could not be distinguished by any of these methods. The data suggest that O157 VTEC strains are members of one clone that has become widely distributed.     

Restriction endonuclease analysis of chromosomal DNA from Listeria monocytogenes strains

Restriction endonuclease analysis of chromosomal DNA was applied to thirteen Listeria monocytogenes strains alongside the more conventional typing methods of serotyping and phage typing. The organisms were isolated from cases of sporadic listeriosis (nine strains); from an occasional nosocomial cluster (two strains); and from food samples (two strains).Purified DNAs were digested with EcoRI restriction endonuclease, and restriction fragments separated by electrophoresis. Restriction patterns correlated well with phage patterns, but also allowed typing of the phage-untypable strains.DNA fingerprinting appears to be a potentially helpful tool for epidemiological investigations of listeric infections, particularly when phage typing fails to determine the identity or diversity of the isolates.     

Genetic relationships among strains of Salmonella enteritidis in a national epidemic in Switzerland.

A collection of Salmonella enteritidis strains isolated in Switzerland (1965-90) was characterized. The phage type and plasmid profile of isolates were compared with the copy number and insertion loci of the DNA insertion element IS200. Three clonal lines of S. enteritidis were identified by IS200 profile; the various phage types were subtypes reproducibly associated with one of these lines. All human and poultry isolates contained a 38 Mda plasmid which hybridized with a mouse virulence-associated gene probe. In S. enteritidis, the IS200 profile is a race-specific molecular marker of the chromosome, and may be particularly applicable for studying the epidemiology of less common serovars.     

Variations in biochemical phenotypes and phage types of Salmonella enteritidis in Germany 1980-92.

The Phene Plate system for typing Salmonella serotypes (PhP-S) is a simple automated typing method based on biochemical fingerprinting. It gives a quantitative value of the metabolism of various substrates by measuring the speed and intensity of each reaction. The ''biochemical fingerprint'' of each isolate is used to calculate similarities among the tested strains with a personal computer program. We used this system to examine a collection of 86 strains of Salmonella enteritidis isolated from human sporadic cases in Germany between 1980 and 1992. Twenty-three biochemical phenotypes (BPTs) consisting of 9 common (C) and 14 single (S) BPTs were identified. BPTs C2 and C4 containing 20 and 36 strains respectively accounted for 65% of the isolates. Strains of BPT C2 were found over a wide period of time whereas strains of BPT C4 were isolated during the period between 1988 and 1992. With phage typing, 11 discrete phage types (PTs) and 18 strains designated as non-specific type (NST) were identified. PTs 4 and 8 with 39 and 17 strains respectively were the dominant PTs. Strains of PT 8 were isolated over a wide period of time whereas all (except one) strains of PT 4 were isolated between 1988 and 1992. Combination of biochemical fingerprinting and phage typing divided the strains into 25 phenotypes (BPT:PTs). Whilst phenotype C2:8 was found over a number of different years, phenotype C4:4 was isolated only between 1988 and 1992. These findings indicate the presence of one persistent and one recently emerged phenotype among S. enteritidis strains in Germany.(ABSTRACT TRUNCATED AT 250 WORDS)     

江苏省伤寒病原菌、耐药性及噬菌体分型研究

目的:开展对伤寒病原学和耐药性监测以及伤寒噬菌体的分型研究,摸清伤寒流行规律,为制定防治措施提供依据。方法:伤寒沙门菌分型用血清凝集法;药敏试验用WHO推荐的改良K—B法;噬菌体分型用96型伤寒Vi-II型噬菌体分型法。结果:血清学分型为:伤寒、副伤寒甲、副伤寒乙分别占75.1%、12.2%、0.9%,其他型占11.8%。561株伤寒杆菌噬菌体分型率为81.3%,分出25个噬菌体型,其中以D1型、M1型、D2、型J、1型、E1型为主要流行型,分别占18.6%、15.6%、15.4%、12.7%和11.0%。另外,E4、K3和32型在国内和省内为首次报道。不同年份、不同流行地区分型率以及强势噬菌体型分布不同。对磺胺甲基异噁唑、红霉素伤寒耐药菌株分别占96.5%、89.5%;而甲型副伤寒100.0%为耐药株。对复方新诺明伤寒、甲型副伤寒杆菌耐药株分别占79.4%、58.3%。M1型多重耐药现象依然严重。结论:疫情强度与强势流行株及强势株的耐药有关;伤寒沙门菌对多粘菌素B、丁胺卡那、庆大霉素、氯霉素、诺氟沙星、氧氟沙星、头孢他定药物敏感,其结果可供临床治疗与现场防治用药参考。     

Occurrence of H-antigen Z66 of R phase in cultures of Salmonella serovar typhi originated from Indonesia

Eighteen strains of Salmonella choleraesuis subsp. choleraesuis serovar Typhi (S. typhi) isolated from blood of patients in Japan who had visited Indonesia and returned before the onset of typhoid fever were found to possess the H-antigen Z66 reported by Guinée et al. (1981) but had the naturally occurring H-antigen d. They were not lysed by any of the phages of the Vi phage typing system. After passage through semi-solid medium containing H-Z66 antiserum, H-antigens of 11 of 18 cultures with H-Z66 phage changed to H-j and those of 2 others to H-d, while the remaining 5 were immobilized. With cultures in the H-d or H-j phages, change of the H-antigens did not occur when they were cultured in semi-solid medium containing homologous H-antiserum. These phase induction experiments as well as colony examination of original cultures suggest that H-Z66 phase is unstable and tends to change to the H-j phase. It also suggest that the original H-Z66 cultures in which change of H-antigen to H-d or H-j occurred without difficulty probably represented a mixed population of cells in the H-Z66 and H-d or H-j phases. Since none of 856 isolates from Japan or from imported cases of typhoid fever from Southeast Asia other than Indonesia exhibited the H-Z66 antigen, it was concluded that the focus of typhoid fever caused by S. typhi in H-Z66 phase was probably in Indonesia.     

Application of ribotyping and IS200 fingerprinting to distinguish the five Salmonella serotype O6,7:c:1,5 groups: Choleraesuis sensu stricto, Choleraesuis var. Kunzendorf, Choleraesuis var. Decatur, Paratyphi C, and Typhisuis.

Sixty-seven strains of the five described Salmonella serotypes having antigens 6,7:c:1,5, that is S. enterica serotype Choleraesuis sensu stricto, Choleraesuis var. Kunzendorf, Choleraesuis var. Decatur, Paratyphi C, and Typhisuis, were examined for 16S rrn profile ribotype, presence of IS200 and phenotypic characters, including rate of change of flagellar-antigen phase and nutritional character. Choleraesuis sensu stricto and its Kunzendorf variant had related but distinct ribotypes. Therefore, ribotyping appears to be a suitable method for differentiating Choleraesuis non-Kunzendorf from Choleraesuis var. Kunzendorf. Some strains of Paratyphi C had 16S profiles that resembled that of Choleraesuis non-Kunzendorf, while others resembled that of Choleraesuis var. Kunzendorf. The Typhisuis profiles were like those of Choleraesuis non-Kunzendorf, while the Choleraesuis var. Decatur profiles were unlike those of any of the other four groups. Furthermore, IS200 fingerprinting discriminated between Choleraesuis var. Decatur and the other strains with antigenic formula O6,7:c:1,5, and comparison of IS200 patterns showed a high degree of genetic divergence within Choleraesuis var. Decatur. Our findings show that ribotyping and IS200 fingerprinting, combined with classical microbiological methods, distinguish the groups Choleraesuis non-Kunzendorf, Choleraesuis var. Kunzendorf, Choleraesuis var. Decatur, Paratyphi C and Typhisuis.     

A longitudinal study of Staphylococcus hyicus colonization of vagina of gilts and transmission to piglets.

High Staphylococcus hyicus colonization rates were found in vaginal samples of healthy breeding sows and in skin samples of their offspring. Twenty-two different phage types were identified among the 720 isolates of S. hyicus examined. Two to 13 different phage types were isolated per herd. Phage typing, as well as characterization of about 10% of the isolates by plasmid profiles and antibiogram patterns, showed that, several different clones of S. hyicus could be present simultaneously in vagina of gilts and also on skin of piglets. Generally isolates from the vagina of one animal were identical as regards to phage types, plasmid profiles, and antibiogram patterns during the entire investigation period. Isolates from the skin of piglets were of the same type as their mothers, indicating that vertical transmission had taken place. S. hyicus strains isolated from the skin of piglets within 24 h after birth were identical to strains isolated 3 weeks after birth from the same litter, indicating that the vaginal strains became part of a stable skin flora.     

Use of plasmid profile typing for surveillance of Salmonella enteritidis phage type 4 from humans, poultry and eggs.

Plasmids were found in 1022 of 1089 (94%) of drug-sensitive strains of Salmonella enteritidis phage type 4 from humans (sporadic and outbreak cases), poultry (chickens) and eggs in England and Wales in the 5-year period 1988-92 and 25 plasmid profile patterns were identified. Strains characterized by a single plasmid of 38 MDa predominated (= plasmid profile type SE 38), comprising over 90% of isolates from humans, 70% from poultry and 92% from eggs. Eleven profile types were identified in strains from humans, 21 in strains from poultry and 3 in strains from eggs. Eight of the 11 patterns identified in human isolates were found in strains from poultry and 2 in strains from eggs. In contrast 15 patterns seen in poultry were not found in strains from humans. Four percent of strains from humans and 13% from poultry did not carry the 38 MDa plasmid but all strains from eggs were found to carry this plasmid. The second most common profile type in strains isolated between 1981 and 1988 was not identified in strains isolated from 1988-92. It is concluded that plasmid profile typing is a useful method for rapid differentiation within phage type 4 of S. enteritidis but that methods which can discriminate within the predominant profile type, SE 38, are now required.     

Phage typing and PFGE pattern analysis as tools for epidemiological surveillance of Salmonella enterica serovar Bovismorbificans infections

Some years ago, an increase in the number of sporadic cases and outbreaks of salmonellosis due to S. enterica serovar Bovismorbificans was observed in several European countries including Finland, Sweden, England/Wales, Austria, and Germany. In order to understand the recent spread of this serovar and to trace the route of infection back to its source, it was considered necessary to subtype S. Bovismorbificans isolates. Using phage typing (newly described here) and molecular fingerprinting (PFGE-pattern, plasmid profiles and ribotype) the isolates of European origin could be subtyped and compared to S. Bovismorbificans isolates that originated in overseas countries such as Australia, Thailand, India, etc. where this serovar was isolated more frequently. Significant clonal diversity was identified but some of the clonal types of S. Bovismorbificans dominated the epidemics and single cases in Europe as well as in overseas countries. The clonal identity among these isolates indicates an international distribution, new sources of infection, and highlights the urgent requirement for standardized laboratory based surveillance networks (e.g. Enter-Net). Moreover, it is suggested that strains of S. Bovismorbificans will continue to be of concern in public health and that phage typing together with PFGE typing can be applied as reliable and rapid tools for their future monitoring.     

A phage-typing scheme for Salmonella enteritidis

For many years phage typing has proved invaluable in epidemiological studies on Salmonella typhi, S. paratyphi A and B, S. typhimurium and a few other serotypes. A phage-typing scheme for S. enteritidis is described. This scheme to date differentiates 27 types using 10 typing phages.     

Molecular fingerprinting of multidrug-resistant Salmonella enterica serotype Typhi.

For epidemiologic investigations, the primary subdivision of Salmonella Typhi is vi-phage typing; 106 Vi-phage types are defined. For multidrug-resistant strains the most common types have been M1 (Pakistan) and E1 (India, Pakistan, Bangladesh, and the Arabian Gulf); a strain untypable with the Vi phages has been responsible for a major epidemic in Tajikistan. Most often, isolates from the Indian subcontinent have been resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, tetracyclines, and trimethoprim; but in the 1997 Tajikistan outbreak, the epidemic strain was also resistant to ciprofloxacin. For multidrug-resistant strains, subdivision within phage type can be achieved by plasmid profile typing and pulsed-field gel electrophoresis.     

IS200 fingerprint of Salmonella enterica serotype Typhimurium human strains isolated in Sardinia.

A collection of Salmonella enterica serotype Typhimurium human strains isolated in Northern Sardinia (Italy) was examined for the insertion sequence IS200, phage type, antibiotic profile, ribotyping polymorphisms and plasmid profile. All clinical isolates studied contained from 4 to 10 copies of the IS200 element. IS200 permitted to discriminate Typhimurium strains and to identify five IS200 types, some of them circulating in Sardinia at least since 1900. Strains belonging to phage DT104 predominated and correlated with a specific IS200 pattern.