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Veterinary World Feb 2024Among serotypes, serotype 2 is the most significant serotype that causes serious diseases in pigs and humans worldwide. The present study aimed to estimate the global...
BACKGROUND AND AIM
Among serotypes, serotype 2 is the most significant serotype that causes serious diseases in pigs and humans worldwide. The present study aimed to estimate the global prevalence of serotype 2 isolated from pigs, determine its trend, and explore the factors associated with this serotype.
MATERIALS AND METHODS
We retrieved relevant published studies from PubMed, Scopus, and the Web of Science. The retrieved citations were screened for possible inclusion. Relevant data were then extracted from the included studies. The random-effects model was used for all meta-analyses. A subgroup meta-analysis was used to assess the heterogeneity of the prevalence for four characteristics (continents, sampling organs, reporting unit, and pig's health status). A cumulative meta-analysis was performed to determine the cumulative prevalence over time. Meta-regression analysis was used to determine the trend of pooled prevalence of serotype 2 over time.
RESULTS
Of 600 articles retrieved, 36 studies comprising a total sample size of 6939 isolates or samples from 16 countries of four continents were included for meta-analysis. The pooled prevalence of serotype 2 isolated from pigs was 13.6% (95% confidence interval [CI], 10.7%-17.1%), with high heterogeneity among the included studies (Cochran's Q, 431.6; p < 0.001; I = 91.9%; Table-1). No statistical significance was observed among subgroups of the four characteristics examined. However, the pooled prevalence of serotype 2 was as high as 16.0% (95% CI, 12.5%-20.3%; n = 16) in diseased pigs compared with 9.9% (95% CI, 5.6%-17.0%; n = 15) in healthy pigs. The pooled prevalence of serotype 2 isolated from pigs did not significantly decrease over time [regression coefficient = -0.020 (95% CI, 0.046-0.006, p = 0.139)]. The pooled prevalence of serotype 2 isolated from pigs fluctuated slightly between 13.2% and 17.8% from 2007 to 2023, although the pooled prevalence gradually decreased from 30.6% in 1987 to over 20% in 2003.
CONCLUSION
The global prevalence of serotype 2 isolated from pigs was estimated to be 13.6% (approximately 10% in healthy pigs and around 16% in diseased pigs). serotype 2 isolated from pigs did not change significantly over time. These results indicate that serotype 2 remains a problem for the pig industry and poses a threat to human health.
PubMed: 38595647
DOI: 10.14202/vetworld.2024.233-244 -
Emerging Microbes & Infections Dec 2024is a significant and emerging zoonotic pathogen. ST1 and ST7 strains are the primary agents responsible for human infections in China, including the Guangxi Zhuang...
is a significant and emerging zoonotic pathogen. ST1 and ST7 strains are the primary agents responsible for human infections in China, including the Guangxi Zhuang Autonomous Region (GX). To enhance our understanding of ST1 population characteristics, we conducted an investigation into the phylogenetic structure, genomic features, and virulence levels of 73 ST1 human strains from GX between 2005 and 2020. The ST1 GX strains were categorized into three lineages in phylogenetic analysis. Sub-lineage 3-1a exhibited a closer phylogenetic relationship with the ST7 epidemic strain SC84. The strains from lineage 3 predominantly harboured 89K-like pathogenicity islands (PAIs) which were categorized into four clades based on sequence alignment. The acquirement of 89K-like PAIs increased the antibiotic resistance and pathogenicity of corresponding transconjugants. We observed significant diversity in virulence levels among the 37 representative ST1 GX strains, that were classified as follows: epidemic (E)/highly virulent (HV) (32.4%, 12/37), virulent plus (V+) (29.7%, 11/37), virulent (V) (18.9%, 7/37), and lowly virulent (LV) (18.9%, 7/37) strains based on survival curves and mortality rates at different time points in C57BL/6 mice following infection. The E/HV strains were characterized by the overproduction of tumour necrosis factor (TNF)-α in serum and promptly established infection at the early phase of infection. Our research offers novel insights into the population structure, evolution, genomic features, and pathogenicity of ST1 strains. Our data also indicates the importance of establishing a scheme for characterizing and subtyping the virulence levels of strains.
Topics: Streptococcus suis; Streptococcal Infections; China; Humans; Phylogeny; Virulence; Animals; Mice; Genome, Bacterial; Genomic Islands; Female; Genomics; Virulence Factors
PubMed: 38578304
DOI: 10.1080/22221751.2024.2339946 -
PloS One 2024Streptococcus suis serotype 2 (SS2) is an important porcine pathogen that causes diseases in both swine and human. For rapid SS2 identification, a novel latex...
Streptococcus suis serotype 2 (SS2) is an important porcine pathogen that causes diseases in both swine and human. For rapid SS2 identification, a novel latex agglutination test (LAT) based on heavy-chain variable domain antibody (VH) was developed. Firstly, the soluble 47B3 VH antibody fragment from a phage display library, in which cysteine residues were engineered at the C-terminus, was expressed in Escherichia coli. The purified protein was then gently reduced to form monomeric soluble 47B3 VH subsequently used to coat with latex beads by means of site-specific conjugation. The resulting VH-coated beads gave a good agglutination reaction with SS2. The LAT was able to distinguish S. suis serotype 2 from serotype 1/2, which shares some common sugar residues, and showed no cross-reaction with other serotypes of S. suis or other related bacteria. The detection sensitivity was found to be as high as 1.85x106 cells. The LAT was stable at 4°C for at least six months without loss of activity. To the best of our knowledge, this is the first LAT based on a VH antibody fragment that can be considered as an alternative for conventional antibody-based LAT where VHs are the most favored recombinant antibody.
Topics: Animals; Humans; Swine; Serogroup; Streptococcus suis; Latex Fixation Tests; Immunoglobulin Fragments; Recombinant Proteins; Escherichia coli; Streptococcal Infections; Swine Diseases
PubMed: 38568909
DOI: 10.1371/journal.pone.0299691 -
PLoS Pathogens Mar 2024Porcine reproductive and respiratory syndrome virus (PRRSV) is known to suppress the type I interferon (IFNs-α/β) response during infection. PRRSV also activates the...
A clinically attenuated double-mutant of porcine reproductive and respiratory syndrome virus-2 that does not prompt overexpression of proinflammatory cytokines during co-infection with a secondary pathogen.
Porcine reproductive and respiratory syndrome virus (PRRSV) is known to suppress the type I interferon (IFNs-α/β) response during infection. PRRSV also activates the NF-κB signaling pathway, leading to the production of proinflammatory cytokines during infection. In swine farms, co-infections of PRRSV and other secondary bacterial pathogens are common and exacerbate the production of proinflammatory cytokines, contributing to the porcine respiratory disease complex (PRDC) which is clinically a severe disease. Previous studies identified the non-structural protein 1β (nsp1β) of PRRSV-2 as an IFN antagonist and the nucleocapsid (N) protein as the NF-κB activator. Further studies showed the leucine at position 126 (L126) of nsp1β as the essential residue for IFN suppression and the region spanning the nuclear localization signal (NLS) of N as the NF-κB activation domain. In the present study, we generated a double-mutant PRRSV-2 that contained the L126A mutation in the nsp1β gene and the NLS mutation (ΔNLS) in the N gene using reverse genetics. The immunological phenotype of this mutant PRRSV-2 was examined in porcine alveolar macrophages (PAMs) in vitro and in young pigs in vivo. In PAMs, the double-mutant virus did not suppress IFN-β expression but decreased the NF-κB-dependent inflammatory cytokine productions compared to those for wild-type PRRSV-2. Co-infection of PAMs with the mutant PRRSV-2 and Streptococcus suis (S. suis) also reduced the production of NF-κB-directed inflammatory cytokines. To further examine the cytokine profiles and the disease severity by the mutant virus in natural host animals, 6 groups of pigs, 7 animals per group, were used for co-infection with the mutant PRRSV-2 and S. suis. The double-mutant PRRSV-2 was clinically attenuated, and the expressions of proinflammatory cytokines and chemokines were significantly reduced in pigs after bacterial co-infection. Compared to the wild-type PRRSV-2 and S. suis co-infection control, pigs coinfected with the double-mutant PRRSV-2 exhibited milder clinical signs, lower titers and shorter duration of viremia, and lower expression of proinflammatory cytokines. In conclusion, our study demonstrates that genetic modification of the type I IFN suppression and NF-κB activation functions of PRRSV-2 may allow us to design a novel vaccine candidate to alleviate the clinical severity of PRRS-2 and PRDC during bacterial co-infection.
Topics: Swine; Animals; Porcine respiratory and reproductive syndrome virus; Cytokines; NF-kappa B; Coinfection; Macrophages, Alveolar; Interferon Type I; Porcine Reproductive and Respiratory Syndrome
PubMed: 38547254
DOI: 10.1371/journal.ppat.1012128 -
Vaccines Mar 2024is an important zoonotic pathogen that mainly causes meningitis, septicemia, and arthritis. Due to the limited cross-protection between numerous serotypes, the existing...
is an important zoonotic pathogen that mainly causes meningitis, septicemia, and arthritis. Due to the limited cross-protection between numerous serotypes, the existing inactive vaccines in clinical use fail to offer sufficient protection. In this study, a gene deletion-attenuated strain Δ-m (P353L)-SC-19 was constructed by deleting and genes from the epidemic strain SC-19 with a mutation of SLY (P353L). The safety of Δ-m (P353L)-SC-19 was confirmed in both in vitro and in vivo experiments. We further demonstrated that immunization with Δ-m (P353L)-SC-19 induced significant cellular immunity and humoral immunity in mice and protected against infections caused by type 2 strain SC-19 (100% protection) and type 9 strain S29 (50% protection), while also preventing meningitis induced by S29. This study highlights the potential of using CPS-deficient strains to achieve cross-protection against different serotypes and develop a promising universal live vaccine.
PubMed: 38543917
DOI: 10.3390/vaccines12030283 -
Microorganisms Feb 2024Respiratory illnesses present a significant threat to porcine health, with co-infections involving Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), (),...
Establishment and Application of a Quadruplex Real-Time Reverse-Transcription Polymerase Chain Reaction Assay for Differentiation of Porcine Reproductive and Respiratory Syndrome Virus, Porcine Circovirus Type 2, Porcine Circovirus Type 3, and .
Respiratory illnesses present a significant threat to porcine health, with co-infections involving Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), (), Porcine Circovirus Type 2 (PCV2), and Porcine Circovirus Type 3 (PCV3) acting as the primary causative agents. As a result, the precise diagnosis of PRRSV, PCV2, PCV3 and is of paramount importance in the prevention and control of respiratory diseases in swine. Therefore, we conducted a molecular bioinformatical analysis to concurrently detect and differentiate PRRSV, PCV2, PCV3 and . We selected the ORF6 gene of PRRSV, the ORF2 gene of PCV2 and PCV3, and the glutamate dehydrogenase (GDH) gene of as targets. Specific primers and probes were designed for each pathogen, and following meticulous optimization of reaction conditions, we established a multiple TaqMan fluorescence quantitative PCR detection method. Subsequently, we subjected this method to a comprehensive assessment, evaluating its specificity, sensitivity, and repeatability. The research results demonstrated that the established multiple TaqMan fluorescence quantitative PCR detection method displays displayed exemplary specificity, with no instances of cross-reactivity with other pathogens. The method's minimum detection concentrations for PRRSV, PCV2, PCV3, and were 2.80 × 10 copies/µL, 1.96 × 10 copies/µL, 2.30 × 10 copies/µL, and 1.75 × 10 copies/µL, respectively. When applied to the analysis of 30 clinical samples, the results closely mirrored those obtained through Chinese standard uniplex real-time qPCR detection method for PRRSV, as well as the general PCR methods for , PCV2, and PCV3. This study underscores the robust specificity, high sensitivity, and consistent stability of the multiple TaqMan fluorescence quantitative PCR detection method that we have developed. It is ideally suited to the clinical monitoring of PRRSV, PCV2, PCV3, and , and it carries significant importance in ongoing efforts to prevent and manage respiratory diseases in porcine populations.
PubMed: 38543477
DOI: 10.3390/microorganisms12030427 -
Microbial Genomics Mar 2024is a leading cause of infection in pigs, causing extensive economic losses. In addition, it can also infect wild fauna, and can be responsible for severe infections in...
is a leading cause of infection in pigs, causing extensive economic losses. In addition, it can also infect wild fauna, and can be responsible for severe infections in humans. Increasing antimicrobial resistance (AMR) has been described in worldwide and most of the AMR genes are carried by mobile genetic elements (MGEs). This contributes to their dissemination by horizontal gene transfer. A collection of 102 strains isolated from humans, pigs and wild boars in France was subjected to whole genome sequencing in order to: (i) study their genetic diversity, (ii) evaluate their content in virulence-associated genes, (iii) decipher the mechanisms responsible for their AMR and their association with MGEs, and (iv) study their ability to acquire extracellular DNA by natural transformation. Analysis by hierarchical clustering on principal components identified a few virulence-associated factors that distinguish invasive CC1 strains from the other strains. A plethora of AMR genes (=217) was found in the genomes. Apart from the frequently reported (B) and (O) genes, more recently described AMR genes were identified [(F)/, (D)]. Modifications in PBPs/MraY and GyrA/ParC were detected in the penicillin- and fluoroquinolone-resistant isolates respectively. New AMR gene-MGE associations were detected. The majority of the strains have the full set of genes required for competence, i.e for the acquisition of extracellular DNA (that could carry AMR genes) by natural transformation. Hence the risk of dissemination of these AMR genes should not be neglected.
Topics: Humans; Animals; Swine; Streptococcus suis; Virulence; France; Virulence Factors; DNA
PubMed: 38536216
DOI: 10.1099/mgen.0.001224 -
Antibiotics (Basel, Switzerland) Mar 2024Streptococci are a type of bacteria that can cause severe illnesses in humans and animals. Some typical species like , or atypical species like and, , can cause...
Streptococci are a type of bacteria that can cause severe illnesses in humans and animals. Some typical species like , or atypical species like and, , can cause infections like septicemia, meningitis, endocarditis, arthritis, and septic shock. is considered a newly emerging zoonotic pathogen. Although human streptococcal infection outbreaks are rare, it is appropriate to review the main streptococcal species isolated in pig farms in western Romania, due to the high degree of antibiotic resistance among most isolates commonly used in human treatment. This study examines the resistance patterns of these isolates over 5 years (2018-2023). The research investigated the antimicrobial susceptibility of 267 strains of spp. isolated from pigs, primarily from lung and brain tissues. This report is the first to describe the distribution of atypical species (SDSE, , , , ) in Romania, as well as the antibiotic resistance profile of these potentially zoonotic species. It is important to re-evaluate and consider the high rates of resistance of to tetracyclines, lincosamides, macrolides, and aminoglycosides, as well as the high recovery rates of from the lungs and brain when treating swine diseases.
PubMed: 38534712
DOI: 10.3390/antibiotics13030277 -
Heliyon Mar 2024is a bacterial gram-positive pathogen that causes invasive infections in swine and is also a zoonotic disease agent. Traditional molecular typing techniques such as... (Review)
Review
is a bacterial gram-positive pathogen that causes invasive infections in swine and is also a zoonotic disease agent. Traditional molecular typing techniques such as ribotyping, multilocus sequence typing, pulse-field gel electrophoresis, or randomly amplified polymorphic DNA have been used to investigate population structure, evolution, and genetic relationships and support epidemiological and virulence investigations. However, these traditional typing techniques do not fully reveal the genetically heterogeneous nature of strains. The high-resolution provided by whole-genome sequencing (WGS), which is now more affordable and more commonly available in research and clinical settings, has unlocked the exploration of genetics at full resolution, permitting the determination of population structure, genetic diversity, identification of virulent clades, genetic markers, and other bacterial features of interest. This approach will likely become the new gold standard for strain typing as WGS instruments become more widely available and traditional typing techniques are gradually replaced.
PubMed: 38509941
DOI: 10.1016/j.heliyon.2024.e27818 -
Veterinary Research Mar 2024Streptococcus suis serotype 2 is a major swine pathogen and a zoonotic agent, causing meningitis in both swine and humans, responsible for substantial economic losses to...
Streptococcus suis serotype 2 is a major swine pathogen and a zoonotic agent, causing meningitis in both swine and humans, responsible for substantial economic losses to the swine industry worldwide. The pathogenesis of infection and the role of bacterial cell wall components in virulence have not been fully elucidated. Lipoproteins, peptidoglycan, as well as lipoteichoic acids (LTA) have all been proposed to contribute to virulence. In the present study, the role of the LTA in the pathogenesis of the infection was evaluated through the characterisation of a mutant of the S. suis serotype 2 strain P1/7 lacking the LtaS enzyme, which mediates the polymerization of the LTA poly-glycerolphosphate chain. The ltaS mutant was confirmed to completely lack LTA and displayed significant morphological defects. Although the bacterial growth of this mutant was not affected, further results showed that LTA is involved in maintaining S. suis bacterial fitness. However, its role in the pathogenesis of the infection appears limited. Indeed, LTA presence reduces self-agglutination, biofilm formation and even dendritic cell activation, which are important aspects of the pathogenesis of the infection caused by S. suis. In addition, it does not seem to play a critical role in virulence using a systemic mouse model of infection.
Topics: Humans; Mice; Animals; Swine; Streptococcus suis; Serogroup; Cell Shape; Virulence; Streptococcal Infections; Rodent Diseases; Swine Diseases
PubMed: 38504299
DOI: 10.1186/s13567-024-01287-w