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Takamatsu D, Wongsawan K, Osaki M, Nishino H, Ishiji T, Tharavichitkul P, Khantawa B, Fongcom A, Takai S, Sekizaki T. Streptococcus suis in humans, Thailand. Emerg Infect Dis 2008; 14:181-3. [PMID: 18258106 PMCID: PMC2600138 DOI: 10.3201/eid1401.070568] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Streptococcus suis in Humans, Thailand
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Lee GT, Chiu CY, Haller BL, Denn PM, Hall CS, Gerberding JL. Streptococcus suis meningitis, United States. Emerg Infect Dis 2008; 14:183-5. [PMID: 18258107 PMCID: PMC2600143 DOI: 10.3201/eid1401.070930] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Streptococcus suis Meningitis, United States
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78
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Ju AP, Wang CJ, Zheng F, Pan XZ, Dong YQ, Ge JC, Lu CP, Tang JQ. [Study on molecular epidemiology of major pathogenic Streptococcus suis serotypes in middle part of Jiangsu province]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2008; 29:151-154. [PMID: 18686855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To determine the prevalence of Streptococcus suis and major pathogenic serotypes in middle part of Jiangsu province. METHODS Tonsillar specimens from 303 slaughtered pigs aged 6 to 8 months were investigated for the presence of Streptococcus suis and major pathogenic serotypes by polymerase chain reaction (PCR) method. Bacteriological examination compared with molecular genetics identification for three Streptococcus suis isolates were also done. RESULTS The overall carrier rate of Streptococcus suis was up to 88.0%, with the percentages of serotype 1(14), 2(1/2), 7 and 9 were 9.6%, 8.5%, 11.3% and 29.5% respectively in 2005. While in 2006, the prevalence of Streptococcus suis was 82.5%, with capsular types 1 (14), 2 (1/2), 7 and 9 were accounted for 17.6%, 2.4%, 25.8% and 20.0% of all the specimens. All the three isolates belonged to Streptococcus suis serotype 2,named 2a, 2f and 14e, which exhibiting the virulent phenotype cps2+/gdh+/mrp-/lepf-/sly-/fbps+/orf2+/89k-, cps2+/lgdh+/mrp-/epf-/sly-/fbps-/orf2-/89k- and cps2+/gdh+/mrp-/epf-/sly-/fbps/orf2-/ respectively. These isolates were all susceptible to amoxicillin, ampicillin, penicillin and resistant to amikacin and tetraycline. Clinical signs were not noted in BALB/c mice and rabbit. CONCLUSION Prevalence of the Streptococcus suis among the healthy herds in the areas was very high, with various capsule types of Streptococcus suis involved in the same herds, and the virulent phenotype of these 3 isolates were very different from those prevalent Streptococcus suis serotype 2 virulent isolates frequently discovered from the epidemic areas.
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Huang G, Li JM, Huang DH. [Study on the epidemiologic characteristics of human Streptococcus suis infection in Hechi city, Guangxi]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2008; 29:207-208. [PMID: 18686873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Gu H, Lu C. [Identification and characterization of a novel infection-related factor (cell wall hydrolase/autolysin) of Streptococcus suis serotype 2]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 2008; 48:68-72. [PMID: 18338579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Streptococcus suis serotype 2 (SS2) is an economically important, zoonotic agent causing death and disease in both human and swine. According to published SS2 European strain P1/7 complete genomic sequence, primers for detection and amplification autolysin were designed. Autolysin gene was detected by PCR with genomic DNA of HA9801 (Jiangsu isolate), ZY05719 (Sichuan isolate), ATCC43765 (reference strain), other SS2 isolates from different regions, and strains of other different serotypes (such as serotype 1, 1/2, 7 and 9). PCR results showed that all 27 SS2 virulent isolates harbored gene autolysin, but not in non-virulent SS2 strain. Among other serotypes, only serotype 7 strain had this gene. The complete autolysin genes of HA9801 and ZY05719 were respectively amplified by PCR and sequenced. Their putative protein sequences were analyzed through online software, results showed both had six repeated domain "GBS_Bsp-like" and one domain "N-acetylmuramoyl-L-alanine amidase". In addition, sequence similarity analysis demonstrated that autolysins of the two strains (HA9801 and ZY05719) showed high homologue to that of European strain P1/7 (99.8%), but obviously differed from Canada strain 89/1589, the latter lacked one domain "GBS Bsp-like". Software DNASTAR was used to analyze autolysin protein sequence and predicted its putative antigenicity. Then partial antigentic segment of autolysin was amplified, cloned and inserted into expression vector pET30a(+), and induced by IPTG to express recombinant autolysin. Its reactivity was analyzed by SDS-PAGE and western blot with swine convalescent sera, blot result showed that the recombinant protein had good reactivity and could be considered as a vaccine candidate.
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Ju AP, Wang CJ, Li M, Cheng G, Zheng F, Pan XZ, Lu CP, Tang JQ. [Construction of RevS gene knock-out mutant of Streptococcus suis serotype 2]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2008; 29:59-64. [PMID: 18785481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To construct a gene knock-out mutant of response regulator named RevS in Streptococcus suis serotype 2 virulent strain 05ZYH33, and to investigate the effects of its deletion on the biological characters of this pathogen and the pathogenesis to mice and piglets. METHODS Recombinant gene knock-out vector consisting of Spc(r) cassette was constructed and flanking was constructed consisting of Spc(r) cassette with flanking homology regions to the RevS genes while the isogenic RevS-deficient mutant was screened by allelic replacement. The effects of RevS deletion on the basic biological characters of 05ZYH33 including growth stability, colonial morphology, haemolysis, Gram staining, growth curve and protein expression were examined in vitro. The mice and piglets were infected with 10(8) CFU wild virulent and mutant isolates. RESULTS PCR analysis confirmed that the coding genes of RevS were replaced completely by Spc(r) cassette and the basic biological characters of 05ZYH33 did not undergo any apparent change. Balb/c mice infection assay indicated that RevS play a role in the pathogenesis of Streptococcus suis infections, while no remarkable difference was observed in the piglets' pathogenesis infection rates between mutant isolates deltaA05ZYH33 and wild-type isolates 05ZYH33. CONCLUSION The mutant of Streptococcus suis 05ZYH33 response regulator was successfully constructed, while the mutation did not obviously affect the bacterial biological characters, while the knock-out mutant of RevS was shown to be attenuated in pathogenesis to mice and piglets.
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Gottschalk M, Segura M, Xu J. Streptococcus suis infections in humans: the Chinese experience and the situation in North America. Anim Health Res Rev 2007; 8:29-45. [PMID: 17692141 DOI: 10.1017/s1466252307001247] [Citation(s) in RCA: 245] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Infections caused by Streptococcus suis are considered a global problem in the swine industry. In this animal species, S. suis is associated with septicemia, meningitis, endocarditis, arthritis and, occasionally, other infections. Moreover, it is an agent of zoonosis that afflicts people in close contact with infected pigs or pork-derived products. Although sporadic cases of S. suis infection in humans have been reported, a large outbreak due to S. suis serotype 2 emerged in the summer of 2005 in Sichuan, China. A similar outbreak was observed in another Chinese province in 1998. Symptoms reported in these two outbreaks include high fever, malaise, nausea and vomiting, followed by nervous symptoms, subcutaneous hemorrhage, septic shock and coma in severe cases. The increased severity of S. suis infections in humans, such as a shorter incubation time, more rapid disease progression and higher rate of mortality, underscores the critical need to better understand the factors associated with pathogenesis of S. suis infection. From the 35 capsular serotypes currently known, serotype 2 is considered the most virulent and frequently isolated in both swine and humans. Here, we review the epidemiological, clinical and immunopathological features of S. suis infection in humans.
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Camporese A, Tizianel G, Bruschetta G, Cruciatti B, Pomes A. Human meningitis caused by Streptococcus suis: the first case report from north-eastern Italy. LE INFEZIONI IN MEDICINA 2007; 15:111-4. [PMID: 17598998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We describe the first case of Streptococcus suis meningitis in the north-east of Italy. We would like to stress that Streptococcus suis should be seriously considered in the differential diagnosis of human meningitis especially in adults with a recent history of close contact with pigs or unprocessed pork meat.
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Xiong Y, Liu Q, Qin FY, Bai Y, Zhu W, Li HM, Guo JG, Qin L, Pan J, Long JM, Chen L. [Study on the molecular epidemiology of Streptococcus suis type 2 from healthy pigs in Guangxi]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2007; 28:593-596. [PMID: 17939392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
OBJECTIVE In order to investigate the positive rate of streptococcus suis type 2 and the genes of their suilysin (sly), extracellular protein (epf) and muramidasa-released protein ( mrp) and to understand the antibiotic susceptibility of S. suis type 2. METHODS S. suis type 2, isolated from slaughtered healthy pig's tonsil in 10 county area of Guangxi, were identified by Multiplex PCR, and the genes of their sly, epf, mrp and the antimicrobial sensitivity analysis were performed. RESULTS 1105 strains of Streptococcus including 667 strains of S. suis and 33 strains of S. suis type 2 were detected from 1179 samples. In these S. suis type 2 strains, there were 22 strains of sly + mrp + epf+ type,1 strain of sly + mrp + epf - type, 2 strains of sly - mrp + epf + type, 7 strains of sly - mrp + epf - type and 1 strain of sly - mrp - epf- type. When these strains were subjected to be tested with penicillin, eritrocina, vacocin, gentamycin, specti-nomysin, enraxacin, ciprofloxaxin, cephalothin VI, sulfadiazine sodium, cyantin, mycifradin, amikacin and achromcin, some were found to be resistant to but most strains were susceptible to cephalothin VI, penicillin and enraxacin. There were 31, 29 and 27 strains over medium sensitivity, respectively, but 28 and 27 resistant strains to amikacin and achromcin were found. CONCLUSION The positive rate of S. suis type 2 in clinical healthy pigs was low (2.8%) and did not show obvious difference between the counties with or without a history of S. suis infection. All the isolated strains were susceptible to cephalothin VI, but most strains were virulent.
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Wilson TL, Jeffers J, Rapp-Gabrielson VJ, Martin S, Klein LK, Lowery DE, Fuller TE. A novel signature-tagged mutagenesis system for Streptococcus suis serotype 2. Vet Microbiol 2007; 122:135-45. [PMID: 17275218 DOI: 10.1016/j.vetmic.2006.12.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Revised: 12/20/2006] [Accepted: 12/27/2006] [Indexed: 11/26/2022]
Abstract
Streptococcus suis is an economically important, zoonotic pathogen causing death and disease in swine. The objectives of this study were to develop a signature-tagged mutagenesis (STM) system for S. suis serotype 2 and to identify genes required for in vivo virulence. Identification of such candidate genes may lead to a better understanding of the pathogenesis of S. suis and may provide substrate for the discovery of new vaccines. A novel STM approach was designed to allow for a higher throughput assay of mutants using the Luminex xMAP system. Additionally, to speed the identification process, a direct genomic DNA sequencing method was developed that overcomes the problems associated with the presence of repetitive insertion sequences. Approximately 2600 mutants were screened through both mouse and caesarian-derived, colostrum-deprived (CDCD) pig models. The disrupted ORF was identified for each potential attenuated mutant, and mutants with distinct and unique mutated ORFs were analyzed individually for attenuation in mouse and CDCD pig models. A variety of genes were identified, including previously known genes essential to the virulence of other organisms, genes involved in capsule biosynthesis, a regulator of suilysin expression, and several conserved or predicted genes. Of the 22 mutants identified as attenuated in either animal model, eight insertion mutants caused no mortality in both mouse and pig models.
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Fittipaldi N, Gottschalk M, Vanier G, Daigle F, Harel J. Use of selective capture of transcribed sequences to identify genes preferentially expressed by Streptococcus suis upon interaction with porcine brain microvascular endothelial cells. Appl Environ Microbiol 2007; 73:4359-64. [PMID: 17483264 PMCID: PMC1932796 DOI: 10.1128/aem.00258-07] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
By using the selective capture of transcribed sequences (SCOTS) approach, we identified 28 genes preferentially expressed by the major swine pathogen and zoonotic agent Streptococcus suis upon interaction with porcine brain microvascular endothelial cells. Several of these genes may be considered new S. suis candidate virulence factors. Results from this study demonstrate the suitability of SCOTS for the elucidation of gene expression in streptococcal species and may contribute to a better understanding of the pathogenesis of S. suis infections.
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Neis C, Rohde J, Valentin-Weigand P, Baums CG. [Investigation of a possible chain of Streptococcus suis infection in a pig breeding community using PCR-based genotyping]. BERLINER UND MUNCHENER TIERARZTLICHE WOCHENSCHRIFT 2007; 120:202-6. [PMID: 17555039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Streptococcus (S.) suis plays an important role in pig breeding causing invasive diseases such as meningitis and polyarthritis. Herd problems with Streptococcus suis are common in many pig farms and are frequently characterised by disease outbreaks. In this context, it is often important to identify chains of infection, e.g. between a farrow-to-wean and a grower farm. In the following case report a possible chain of infection among the different farms of a farrow-to-finish system was investigated. In two grower units herd problems with S. suis were present; the mortality was higher than 5 %. It appeared likely, that the streptococci causing these problems were transmitted from a single farrow-to-wean unit to the two different grower farms. In the respective farms swabs were taken from different healthy animals and, in the case of the grower farms, also from the infected animals. Genotypic profiling of strains by a multiplex-PCR and AFLP typing method revealed that two different S. suis pathotypes were responsible for the herd problems. Both pathotypes could not be detected in the farrow-to-wean farm.Thus, a chain of infection originating from the farrow-to-wean farm appeared unlikely. The multiplex PCR was in this case sufficient to elucidate the described problem.
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Wang K, Lu C. Adhesion activity of glyceraldehyde-3-phosphate dehydrogenase in a Chinese Streptococcus suis type 2 strain. BERLINER UND MUNCHENER TIERARZTLICHE WOCHENSCHRIFT 2007; 120:207-9. [PMID: 17555040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A total of 36 streptococcal strains, including seven S. equi ssp.zooepidemicus, two S. suis type 1 (SS1), 24 SS2, two SS9, and one SS7, were tested for glyceraldehyde-3-phosphate dehydrogenase gene (gapdh). Except from non-virulent SS2 strain T1 5, all strains harboured gapdh. The gapdh of Chinese Sichuan SS2 isolate ZY05719 and Jiangsu SS2 isolate HA9801 were sequenced and then compared with published sequences in the GenBank. The comparison revealed a 99.9 % and 99.8 % similarity of ZY05719 and HA9801, respectively, with the published sequence. Adherence assay data demonstrated a significant ((p<0.05)) reduction in adhesion of SS2 in HEp-2 cells pre-incubated with purified GAPDH compared to non pre-incubated controls, suggesting the GAPDH mediates SS2 bacterial adhesion to host cells.
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Vanier G, Segura M, Gottschalk M. Characterization of the invasion of porcine endothelial cells by Streptococcus suis serotype 2. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 2007; 71:81-9. [PMID: 17479770 PMCID: PMC1829181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Streptococcus suis serotype 2 is an important swine pathogen associated mainly with meningitis. In a previous study, we demonstrated the ability of S. suis serotype 2 to adhere to and invade immortalized porcine brain microvascular endothelial cells (PBMECs) forming the blood-brain barrier. The aim of the current work was to further characterize the mechanism(s) by which S. suis invades porcine endothelial cells. The ability of several S. suis strains to interact with PBMECs was not found to correlate with their geographic origin, virulence, host of origin, or suilysin production. Characterization studies demonstrated that proteinaceous adhesins/invasins, cell wall components, lipoteichoic acid, and serum components (including fibronectin) were involved in interactions between S. suis and PBMECs. In addition to PBMECs, S. suis was able to adhere to and invade 2 porcine aortic endothelial cell lines and primary PBMECs.
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Chen C, Tang J, Dong W, Wang C, Feng Y, Wang J, Zheng F, Pan X, Liu D, Li M, Song Y, Zhu X, Sun H, Feng T, Guo Z, Ju A, Ge J, Dong Y, Sun W, Jiang Y, Wang J, Yan J, Yang H, Wang X, Gao GF, Yang R, Wang J, Yu J. A glimpse of streptococcal toxic shock syndrome from comparative genomics of S. suis 2 Chinese isolates. PLoS One 2007; 2:e315. [PMID: 17375201 PMCID: PMC1820848 DOI: 10.1371/journal.pone.0000315] [Citation(s) in RCA: 210] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Accepted: 02/19/2007] [Indexed: 12/31/2022] Open
Abstract
Background Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen, causing more than 200 cases of severe human infection worldwide, with the hallmarks of meningitis, septicemia, arthritis, etc. Very recently, SS2 has been recognized as an etiological agent for streptococcal toxic shock syndrome (STSS), which was originally associated with Streptococcus pyogenes (GAS) in Streptococci. However, the molecular mechanisms underlying STSS are poorly understood. Methods and Findings To elucidate the genetic determinants of STSS caused by SS2, whole genome sequencing of 3 different Chinese SS2 strains was undertaken. Comparative genomics accompanied by several lines of experiments, including experimental animal infection, PCR assay, and expression analysis, were utilized to further dissect a candidate pathogenicity island (PAI). Here we show, for the first time, a novel molecular insight into Chinese isolates of highly invasive SS2, which caused two large-scale human STSS outbreaks in China. A candidate PAI of ∼89 kb in length, which is designated 89K and specific for Chinese SS2 virulent isolates, was investigated at the genomic level. It shares the universal properties of PAIs such as distinct GC content, consistent with its pivotal role in STSS and high virulence. Conclusions To our knowledge, this is the first PAI candidate from S. suis worldwide. Our finding thus sheds light on STSS triggered by SS2 at the genomic level, facilitates further understanding of its pathogenesis and points to directions of development on some effective strategies to combat highly pathogenic SS2 infections.
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Rehm T, Baums CG, Strommenger B, Beyerbach M, Valentin-Weigand P, Goethe R. Amplified fragment length polymorphism of Streptococcus suis strains correlates with their profile of virulence-associated genes and clinical background. J Med Microbiol 2007; 56:102-109. [PMID: 17172524 DOI: 10.1099/jmm.0.46616-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Amplified fragment length polymorphism (AFLP) typing was applied to 116 Streptococcus suis isolates with different clinical backgrounds (invasive/pneumonia/carrier/human) and with known profiles of virulence-associated genes (cps1, -2, -7 and -9, as well as mrp, epf and sly). A dendrogram was generated that allowed identification of two clusters (A and C) with different subclusters (A1, A2, C1 and C2) and two heterogeneous groups of strains (B and D). For comparison, three strains from each AFLP subcluster and group were subjected to multilocus sequence typing (MLST) analysis. The closest relationship and lowest diversity were found for patterns clustering within AFLP subcluster A1, which corresponded with sequence type (ST) complex 1. Strains within subcluster A1 were mainly invasive cps1 and mrp+ epf+ (or epf*) sly+ cps2+ strains of porcine or human origin. A new finding of this study was the clustering of invasive mrp* cps9 isolates within subcluster A2. MLST analysis suggested that A2 correlates with a single ST complex (ST87). In contrast to A1 and A2, subclusters C1 and C2 contained mainly pneumonia isolates of genotype cps7 or cps2 and epf- sly-. In conclusion, this study demonstrates that AFLP allows identification of clusters of S. suis strains with clinical relevance.
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Baums CG, Kaim U, Fulde M, Ramachandran G, Goethe R, Valentin-Weigand P. Identification of a novel virulence determinant with serum opacification activity in Streptococcus suis. Infect Immun 2006; 74:6154-62. [PMID: 17057090 PMCID: PMC1695488 DOI: 10.1128/iai.00359-06] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Streptococcus suis serotype 2 is a porcine and human pathogen with adhesive and invasive properties. In other streptococci, large surface-associated proteins (>100 kDa) of the MSCRAMM family (microbial surface components recognizing adhesive matrix molecules) are key players in interactions with host tissue. In this study, we identified a novel opacity factor of S. suis (OFS) with structural homology to members of the MSCRAMM family. The N-terminal region of OFS is homologous to the respective regions of fibronectin-binding protein A (FnBA) of Streptococcus dysgalactiae and the serum opacity factor (SOF) of Streptococcus pyogenes. Similar to these two proteins, the N-terminal domain of OFS opacified horse serum. Serum opacification activity was detectable in sodium dodecyl sulfate extracts of wild-type S. suis but not in extracts of isogenic ofs knockout mutants. Heterologous expression of OFS in Lactococcus lactis demonstrated that a high level of expression of OFS is sufficient to provide surface-associated serum opacification activity. Furthermore, serum opacification could be inhibited by an antiserum against recombinant OFS. The C-terminal repetitive sequence elements of OFS differed significantly from the respective repeat regions of FnBA and SOF as well as from the consensus sequence of the fibronectin-binding repeats of MSCRAMMs. Accordingly, fibronectin binding was not detectable in recombinant OFS. To investigate the putative function of OFS in the pathogenesis of invasive S. suis diseases, piglets were experimentally infected with an isogenic mutant strain in which the ofs gene had been knocked out by an in-frame deletion. The mutant was severely attenuated in virulence but not in colonization, demonstrating that OFS represents a novel virulence determinant of S. suis.
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Luey CKY, Chu YW, Cheung TKM, Law CCP, Chu MY, Cheung DTL, Kam KM. Rapid pulsed-field gel electrophoresis protocol for subtyping of Streptococcus suis serotype 2. J Microbiol Methods 2006; 68:648-50. [PMID: 17157941 DOI: 10.1016/j.mimet.2006.10.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 10/16/2006] [Accepted: 10/26/2006] [Indexed: 10/23/2022]
Abstract
A rapid pulsed-field gel electrophoresis (PFGE) protocol for subtyping of Streptococcus suis serotype 2 was developed and evaluated using 27 clinical isolates from 22 epidemiologically unrelated patients. Results were matched against antibiogram, virulence genotyping and multi locus sequence typing (MLST). PFGE appeared to be the most discriminatory with numerical index of discrimination (D) equal to 0.87.
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Abstract
Streptococcus bovis has classically been associated with colorectal carcinomas in literature. Curiously enough, no other Streptococcus species have hitherto been associated with such a malignancy or any other tumors. This report presents a case of early-stage colorectal carcinoma diagnosed in a patient with infection with the related Streptococcus species S suis. A discussion of possible pathogenetic implications follows.
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Ye C, Zhu X, Jing H, Du H, Segura M, Zheng H, Kan B, Wang L, Bai X, Zhou Y, Cui Z, Zhang S, Jin D, Sun N, Luo X, Zhang J, Gong Z, Wang X, Wang L, Sun H, Li Z, Sun Q, Liu H, Dong B, Ke C, Yuan H, Wang H, Tian K, Wang Y, Gottschalk M, Xu J. Streptococcus suisSequence Type 7 Outbreak, Sichuan, China. Emerg Infect Dis 2006; 12:1203-8. [PMID: 16965698 PMCID: PMC3291228 DOI: 10.3201/eid1708.060232] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
An outbreak of Streptococcus suis serotype 2 emerged in the summer of 2005 in Sichuan Province, and sporadic infections occurred in 4 additional provinces of China. In total, 99 S. suis strains were isolated and analyzed in this study: 88 isolates from human patients and 11 from diseased pigs. We defined 98 of 99 isolates as pulse type I by using pulsed-field gel electrophoresis analysis of SmaI-digested chromosomal DNA. Furthermore, multilocus sequence typing classified 97 of 98 members of the pulse type I in the same sequence type (ST), ST-7. Isolates of ST-7 were more toxic to peripheral blood mononuclear cells than ST-1 strains. S. suis ST-7, the causative agent, was a single-locus variant of ST-1 with increased virulence. These findings strongly suggest that ST-7 is an emerging, highly virulent S. suis clone that caused the largest S. suis outbreak ever described.
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Johannson LM. Meningitis and septicemia in a 7-week-old piglet caused by dual streptococcal infection. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 2006; 47:796-8. [PMID: 16933560 PMCID: PMC1524847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A 7-week-old piglet was presented with a 2-hour history of neurological signs progressing to death. Necropsy, bacteriologic culture, and immunohistochemical staining indicated an unusual case of Streptococcus suis-like bacterial meningitis and S. suis type 3 septicemia. Management and control of this important bacterial disease are discussed.
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Silva LMG, Baums CG, Rehm T, Wisselink HJ, Goethe R, Valentin-Weigand P. Virulence-associated gene profiling of Streptococcus suis isolates by PCR. Vet Microbiol 2006; 115:117-27. [PMID: 16431041 DOI: 10.1016/j.vetmic.2005.12.013] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 12/14/2005] [Accepted: 12/15/2005] [Indexed: 11/29/2022]
Abstract
Definition of virulent Streptococcus suis strains is controversial. One successful approach for identification of virulent European strains is differentiation of capsular serotypes (or the corresponding cps types) and subsequent detection of virulence-associated factors, namely the extracellular factor (EF, epf), the muramidase-released protein (MRP, mrp) and the hemolysin suilysin (SLY, sly). In this work we present a novel multiplex PCR (MP-PCR) and an mrp variant PCR for identification and characterization of virulent S. suis strains. These new methods were used to identify association of disease with particular profiles of virulence-associated genes. The MP-PCR allowed identification of S. suis through detection of the housekeeping gene gdh, differentiation of four cps types (1, 2, 7 and 9), and detection of epf, mrp, sly and arcA (arginine deiminase from S. suis). Furthermore, this study describes the first PCR assay for differentiation of at least six mrp variants. Expression of the corresponding size variants of MRP was shown for four of the six mrp variants, but was undetectable for the two larger mrp variants in the particular strains investigated. The results of this study suggest that cps7 strains are associated with pneumonia and that variation of mrp is very pronounced among these strains. Gene profiles of invasive, pneumonia and carrier S. suis isolates by combination of PCR assays allowed differentiation of 24 different genotypes among cps1, 2, 7 and 9 strains. Forty-five percent of the invasive S. suis diseases investigated in this study were caused by only two of these genotypes, namely cps2/mrp+/epf+/sly+ and cps9/mrp(*)/epf-/sly+. Thus, this study demonstrates for the first time a uniform profile of the particular virulence-associated genes for the vast majority of the investigated invasive cps9 strains.
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Wangkaew S, Chaiwarith R, Tharavichitkul P, Supparatpinyo K. Streptococcus suis infection: a series of 41 cases from Chiang Mai University Hospital. J Infect 2006; 52:455-60. [PMID: 16690131 DOI: 10.1016/j.jinf.2005.02.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2004] [Accepted: 02/08/2005] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The objectives of this study were (1) to assess the clinical manifestations, treatment, and outcome of Streptococcus suis infection in adult patients in northern Thailand, (2) to evaluate the anti-microbial sensitivity pattern and (3) to determine the predicting factors of high mortality rate. METHODS A retrospective study was conducted at Chiang Mai University Hospital from May 2000 to December 2002. Anti-microbial susceptibility test was performed by agar disk diffusion and the minimal inhibitory concentration (MIC) by E-test. RESULTS Forty-one patients (32 men and nine women, mean age 51 years) with S. suis infection were identified. Three patients had a history of exposure to pig or pork and one patient had a history of raw beef consumption. Clinical manifestations included infective endocarditis, meningitis, sepsis, spondylodiscitis, and endophthalmitis in 16, 13, 10, 1, and 1 patients, respectively. The overall mortality rate was 19.5%. On univariate analysis, low serum albumin, high serum total bilirubin, low platelet, and rapid onset of illness were significantly correlated with high mortality rate. All isolates were sensitive to penicillin (mean MIC90=0.027 microg/ml). CONCLUSIONS S. suis infection is not uncommon in northern Thailand. High suspicion and early detection are important and could lead to the successful treatment.
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99
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Abstract
Sriskandan and Slater discuss the implications of Tang and colleagues' report of the largest known zoonotic outbreak of S. suis, which occurred in Sichuan Province, China, in 2005.
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100
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Tang J, Wang C, Feng Y, Yang W, Song H, Chen Z, Yu H, Pan X, Zhou X, Wang H, Wu B, Wang H, Zhao H, Lin Y, Yue J, Wu Z, He X, Gao F, Khan AH, Wang J, Zhao GP, Wang Y, Wang X, Chen Z, Gao GF. Streptococcal toxic shock syndrome caused by Streptococcus suis serotype 2. PLoS Med 2006; 3:e151. [PMID: 16584289 PMCID: PMC1434494 DOI: 10.1371/journal.pmed.0030151] [Citation(s) in RCA: 280] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2005] [Accepted: 01/10/2006] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Streptococcus suis serotype 2 (S. suis 2, SS2) is a major zoonotic pathogen that causes only sporadic cases of meningitis and sepsis in humans. Most if not all cases of Streptococcal toxic shock syndrome (STSS) that have been well-documented to date were associated with the non-SS2 group A streptococcus (GAS). However, a recent large-scale outbreak of SS2 in Sichuan Province, China, appeared to be caused by more invasive deep-tissue infection with STSS, characterized by acute high fever, vascular collapse, hypotension, shock, and multiple organ failure. METHODS AND FINDINGS We investigated this outbreak of SS2 infections in both human and pigs, which took place from July to August, 2005, through clinical observation and laboratory experiments. Clinical and pathological characterization of the human patients revealed the hallmarks of typical STSS, which to date had only been associated with GAS infection. Retrospectively, we found that this outbreak was very similar to an earlier outbreak in Jiangsu Province, China, in 1998. We isolated and analyzed 37 bacterial strains from human specimens and eight from pig specimens of the recent outbreak, as well as three human isolates and two pig isolates from the 1998 outbreak we had kept in our laboratory. The bacterial isolates were examined using light microscopy observation, pig infection experiments, multiplex-PCR assay, as well as restriction fragment length polymorphisms (RFLP) and multiple sequence alignment analyses. Multiple lines of evidence confirmed that highly virulent strains of SS2 were the causative agents of both outbreaks. CONCLUSIONS We report, to our knowledge for the first time, two outbreaks of STSS caused by SS2, a non-GAS streptococcus. The 2005 outbreak was associated with 38 deaths out of 204 documented human cases; the 1998 outbreak with 14 deaths out of 25 reported human cases. Most of the fatal cases were characterized by STSS; some of them by meningitis or severe septicemia. The molecular mechanisms underlying these human STSS outbreaks in human beings remain unclear and an objective for further study.
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