Molecular confirmation and detection of virulence genes of Streptococcus suis from Pigs in Assam (original) (raw)
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The Veterinary Journal, 2016
The study was designed to determine the prevalence as well as virulence genes of Streptococcus suis in pigs maintained in organized and unorganized farming systems in and around Guwahati, Assam. A total of 497 samples were collected from clinically healthy (n=267) and diseased (n=230) pigs of varying age and either sex. Samples were processed for isolation of S. suis and their identification based on biochemical characteristics and further confirmation through PCR amplification of the housekeeping gene gdh (glutamate dehydrogenase) encoding S. suis capsular biosynthesis. Important virulence genes of S. suis namely, epf, mrp, sly, and arc A were detected by using multiplex PCR. All together seven isolates were confirmed as S. suis. But none of the investigated virulence genes could be demonstrated in the present study.
Journal of medical microbiology, 2017
Carrier pigs have been considered as the major reservoir of Streptococcus suis and couldbe a significant source of human infection. Therefore, we investigated the prevalence and characteristics of latent S. suis in asymptomatic pigs in the pig-farming area of central Thailand, and compared the data to those previously reported in other regions. We collected samples from 340 asymptomatic pigs. S. suis isolates from the samples were confirmed by species-specific PCR (recN PCR). The capsular polysaccharide synthesis gene (cps) types, virulence-associated gene profiles and sequence types (STs) of the isolates were investigated.Results/Key findings. The prevalence of S. suis found in this study was 37 % (125/340 pigs). The most prevalent genotype was mrp-/epf-/sly-. Among the 16 cps-types identified in 135 isolates, cps-type 16 was the most frequent (11 %), whereas 44 % of the isolates were non-typable. In common with the strains causing human sepsis in Thailand, two cps-type 9 isolates ...
The Southeast Asian journal of tropical medicine and public health
This study was designed to determine the incidence of Streptococcus suis infection in slaughtered pigs raised in industrial facility and backyard system in Chiang Mai City, Thailand. A total of 90 tonsils and submaxillary salivary gland/lymph node samples from slaughtered pigs raised in industrial facility and 122 samples from slaughtered pigs raised in backyard system were collected. Isolation and identification of S. suis were conducted using standard bacteriological methods. Farm management and risk factor data were collected by a questionnaire. Serotyping and presence of virulence factor genes, epf, mrp and sly, were determined by multiplex PCR assay. The overall incidence of S. suis in this study was 9% (n = 212) and the incidence is significantly higher in districts located at a greater distance south of Chiang Mai City. S. suis serotype 2 was present more in healthy pigs (43%) than ill pigs (10%). Every S. suis isolate carried mrp and sly and ill pigs carried epf (80%) more t...
Journal of Veterinary Medical Science, 2015
In this present study, the serotype of 40 Streptococcus suis isolates from submaxillary glands of pig carcasses sold in wet markets in Chiang Mai Province, northern Thailand, was investigated. Eleven serotypes, including types 2, 3, 4, 5, 7, 8, 9, 17, 21, 22 and 31, were found in the isolates by a Multiplex PCR combined with serum agglutination. Of the eleven serotypes present, type 3 was the most prevalent, while types 2, 4, 5 and 21 were of primary interest due to their human isolate serotype. The mrp+/epf − /sly − genotype was found to be the most prevalent genotype. This study indicates the importance of effective control of human S. suis infection due to raw pork or pig carcass handling in northern Thailand.
The Journal of veterinary medical science, 2017
Streptococcus suis is an important pig pathogen with potential for human transmission. The serotype distributions and phenotypic characteristics vary over time and among regions; however, little is known about the characteristics of S. suis isolates in Korea. In this study, 240 S. suis isolates collected from pigs in Korea in 2009-2010 were serotyped by coagglutination tests, subsequently screened for three virulence-associated genes (mrp, epf and sly) and tested for antimicrobial susceptibility. As for 80 isolates, the serotypes of which were relevant to human infections, clonal complexes (CCs) were further identified by PCR. Serotype 3 was the most prevalent (15.8%), followed by serotype 2 (15.0%), with geographical variation for each serotype. Overall, 55.4% of the isolates carried mrp, whereas only 3.8% carried epf. CC25 was the most prevalent (41.3%) and was related to serotypes 2 and 9. The isolates showed higher susceptibility to ampicillin (93.4%) and ceftiofur (90.8%) than ...
Antibiotics
A set of 207 Streptococcus suis isolates were collected from ten autonomous communities from Spain in 2019 to 2020 from pigs with meningitis, pneumonic lungs, arthritic joints or other swollen viscera, to a lesser extent. Thirteen capsular types were detected being the most prevalent serotype 2 (21.7%), followed by serotypes 1 (21.3%), 9 (19.3%) and 3 (6.3%). Serotypes 2 and 9 were recovered mainly from the central nervous system (CNS), while serotype 1 was isolated mostly from swollen joints and serotype 3 from the lungs. Twenty-five isolates (12.1%) could not be typed. The most prevalent pathotype was epf + mrp + sly + luxS (49 isolates, 23.8%), and it was related mainly to serotypes 1 and 2. Serotypes 1–3 and 9 were significantly associated with anatomical sites of isolation and virulence factors, serotype 9 (CNS) and serotypes 3 and 9 (lungs) being associated with virulence profiles without the epf gene. S. suis isolates showed globally high antimicrobial resistances, but ampici...
Veterinary Microbiology, 1999
We developed a PCR assay for the rapid and sensitive detection of virulent Streptococcus suis type 2 and highly virulent S. suis type 1 in tonsillar specimens from pigs. The PCR primers were based on the sequence of the gene encoding the EF-protein of virulent S. suis type 2 strains (MRP + EF + ) and highly virulent S. suis type 1 strains (MRP s EF + ) and of the EF* protein of weakly virulent S. suis type 2 strains (MRP + EF * ). The latter strains give rise to larger PCR products than the virulent strains of S. suis type 1 and 2. A positive control template was included in the assay to identify false negative results. The PCR was evaluated using tonsillar specimens from herds known (or suspected) to be infected and herds without a S. suis history. The results obtained with the PCR assay were compared with the results obtained with a newly developed bacteriological examination. In this bacteriological examination we were able to identify the EF-positive strains directly in the tonsillar specimens. From the 99 tonsils examined, 48 were positive in the PCR and 51 negative. All specimens from which EF-positive S. suis strains were isolated were also positive in the PCR assay. Three samples were positive in the PCR, but negative by bacteriological examination. The results demonstrated that the PCR is a highly specific and sensitive diagnostic tool for the detection of pigs carrying virulent strains of S. suis type 2 and highly virulent strains of type 1. Application of the assay may contribute to the control of S. suis infections.
Identification of Streptococcus suis carriage in healthy pigs in Chiang Mai, Thailand
Veterinary Integrative Sciences, 2022
Streptococcus suis (S. suis) belongs to the critical streptococcal swine pathogens affecting financial losses in pig production globally and being concerned as a zoonotic bacterial that causes a severe invasive disease emerging in pigs and humans. Serotype 2 is considered the major serotype and is the most pathogenic S. suis obtained from human cases, and the healthy pigs are known as the major reservoir of S. suis. In this cross-sectional study, S. suis prevalence was conducted in live pigs from 111 farms across Chiang Mai, Thailand. S. suis carriage rate and serotypes were determined from the bacteriological and multiplex PCR method from tonsil swab samples. We found that 18.2% (138/760) of tonsil swab samples and 54.1% (60/111) of pig farms were positive to S. suis, and only one (0.72%) from 138 isolates was identified as serotype 9. Meanwhile, all the remains were identified as non-serotype ½/1/2/7/9/14 strains. In addition, there was an independent relation between age-ranged, farm types, and production systems with S. suis-positive rates at the farm level. The results indicate that both intensive and smallholder production systems can generally be the source of S. suis carriage. Therefore, implementing good husbandry practices and S. suis-infection predisposing factors limiting that appropriate for each farm type is essential to minimize the opportunities of S. suis outbreak in humans.
Foodborne Pathogens and Disease, 2012
Streptococcus suis isolates from diseased pigs were examined for susceptibility to nine antimicrobials, possession of virulence-associated factors (VFs), and distribution of serotypes. The association between antimicrobial resistance (AMR) and serotypes as well as VFs was subsequently assessed. Among the isolates investigated, serotype 2 (66.04%) was mostly prevalent, followed by serotypes 1 (23.27%), 9 (1.26%), and 7 (0.63%), whereas 14 isolates were untypable by the polymerase chain reaction typing method used. Analysis with pulsed-field gel electrophoresis revealed the isolates had diverse DNA macrorestriction patterns. The frequency of antimicrobial resistance among the S. suis isolates was higher than that reported from other countries. It is notable that multiple antimicrobial resistance (three or more antimicrobials) was observed with 98.73% of the S. suis isolates, and the dominant resistance phenotype was erythromycin-tilmicosin-clindamycin-chloramphenicol-levofloxacin-ceftiofur-kanamycin-tetracycline-penicillin (35.85%). The most prevalent VFs were those encoded by muramidase-released protein (61.64%), followed by suilysin (56.60%) and extracellular factor (46.54%). Presence of VFs and the possession of certain AMR phenotypes were significantly associated as determined by statistical analysis. Together, these findings indicate that the clinical S. suis isolates obtained from diseased pigs in China are genetically diverse, are resistant to multiple antibiotics of clinical importance, and carry known virulence factors.
Molecular typing of Streptococcus suis from pigs in Cuba
Biotecnología Aplicada, 2013
Streptococcus suis is a bacterium commonly carried by pigs in the respiratory tract; thus the infections caused by virulent strains are considered a problem in the swine industry. A successful approach for the identifi cation of virulent strains is the differentiation of capsular serotypes using specifi c antisera or the corresponding cps types by geno- typic assessment, with the subsequent detection of virulence associated factors, namely the extracellular factor, the muramidase-released protein and the hemolysin suilysin. Data regarding serological and molecular identifi cation of S. suis from pigs in Cuba are not available. This study was aimed at identifying the capsular types cps2, 7 and 9, as well as three genes related to virulence using PCR assays. According to the results, 31 isolates were evaluated and classifi ed as cps2 (n = 21) or cps9 (n = 4), while six isolates not were typable. Considering the presence in these isolates of the genes mrp, epf and sly, six different ge...