Transboundary and Emerging Diseases最新文献

{"title":"Genetic Characterization of a Linezolid- and Penicillin-Resistant Enterococcus hirae Isolate Co-Harboring poxtA and pbp5fm","authors":"Jinhu Huang,&nbsp;Aijuan Li,&nbsp;Mengli Wang,&nbsp;Shushu Gu,&nbsp;He Hu,&nbsp;Xiaoming Wang,&nbsp;Liping Wang","doi":"10.1155/tbed/9275403","DOIUrl":"https://doi.org/10.1155/tbed/9275403","url":null,"abstract":"<div>\u0000 <p>Linezolid and penicillin are critical for treating multidrug resistant (MDR) Gram-positive infections, but the emergence of resistance to both seriously threatens public health. Here, we first report the cocarrying <i>poxtA</i> (oxazolidinone resistance) and <i>pbp5fm</i> (β-lactam resistance) genes by the plasmid in a strain of <i>Enterococcus hirae</i> HDC14-2 derived from porcine. The isolate also exhibits MDR phenotypes to phenicols, oxazolidinones, tetracyclines, β-lactams, aminoglycosides, macrolides, and lincosamides. Whole-genome sequencing (WGS) revealed these resistance genes, along with <i>tet</i>(<i>L</i>), <i>tet</i>(<i>M</i>), <i>catA</i>, <i>erm</i>(B), <i>aac</i>(<i>6</i>)-<i>aph</i>(<i>2”</i>), <i>aadE</i>, <i>spw</i>, <i>lsa</i>(E), <i>lnu</i>(B), <i>sat4</i>, and <i>aphA3</i>, were clustered in a novel MDR region flanked by IS<i>1216</i> elements on plasmid pHDC14-2.133K. This IS<i>1216</i>-bounded MDR region formed translocatable units (TUs), including an IS<i>1216</i>-<i>poxtA</i> TU that was also identified on a secondary plasmid, pHDC14-2.27K. Functional assays demonstrated the excisability and mobility of these TUs, indicating its potential ability integration into other plasmids or chromosomes. Critically, electrotransformation confirmed the transfer of pHDC14-2.27K (<i>poxtA</i>-carrying) to <i>Enterococcus faecalis</i> JH2-2, with retained TU activity and minimal fitness cost. This study provides the evidence of colocalized <i>poxtA</i> and <i>pbp5fm</i> on plasmids in enterococci, highlighting their role in disseminating pan-resistance among bacteria. Although <i>E. hirae</i> is not an important pathogenic bacterium to humans and animals, but its potential risk to horizontally spread of these resistance genes important in medicine still cannot be ignored.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/9275403","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Safety of Live Attenuated ASFV-G-ΔI177L/ΔLVR Vaccination in Sows With Advanced Pregnancies","authors":"Su Jin Lee,&nbsp;Yeonji Kim,&nbsp;Sun A. Choi,&nbsp;Keun Seung Ahn,&nbsp;Se Young Lee,&nbsp;Xinghua Zheng,&nbsp;Do Soon Kim,&nbsp;Wonjun Kim,&nbsp;Yongwoo Shin,&nbsp;So-Jeong Kim,&nbsp;Sua Choi,&nbsp;Dongseob Tark,&nbsp;Seong Cheol Moon,&nbsp;Weonhwa Jheong,&nbsp;Jung Hyang Sur","doi":"10.1155/tbed/8007143","DOIUrl":"https://doi.org/10.1155/tbed/8007143","url":null,"abstract":"<div>\u0000 <p>African swine fever (ASF) causes severe disease in domestic pigs and wild boars and often results in 100% mortality. The use of attenuated strains in ASF vaccine development, based on the most recently studied ASF virus (ASFV)-Georgia (ASFV-G) strain, has proven effective. In July 2023, Vietnam became the first country in the world to have two indigenously developed ASF vaccines approved for commercial sale locally. In this study, we evaluated the immunogenicity and safety of the live attenuated vaccine (LAV) ASFV-G-ΔI177L/ΔLVR derived from ASFV-G-ΔI177L in five pregnant sows and a control group. The ASFV-G-ΔI177L replicates efficiently in a stable swine cell line. Therefore, the pregnant sows were used to validate the vaccine. Fundamental assessments of clinical symptoms (vaccine safety), parturition performance, vertical transmission presence after birth, and maternal antibodies were conducted before and after colostrum intake following the vaccination with ASF-G-ΔI177L/ΔLVR. The vaccination had no adverse effects and induced a high level of antibody production. Normal delivery was also confirmed without miscarriages. Furthermore, ASF antibodies and the P72 gene were detected in the blood of most piglets that consumed colostrum from vaccinated sows, and transplacental transmission was confirmed in piglets following vaccination. While these results will influence vaccine development and play an important role in preventing lethal ASFV infections, they also highlight the potential of ASFV-G-ΔI177L/ΔLVR to protect even high-risk groups such as pregnant sows and emphasize the importance of continued vigilance and investigation of vaccine safety parameters such as viral shedding, genetic stability, and reproductive efficacy.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/8007143","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multilocus Sequence Typing Unveils Two Novel Genospecies of Borrelia burgdorferi Sensu Lato in Ticks Infesting Cricetid Rodents of Northern Chile","authors":"Catalina Parragué-Migone,&nbsp;Adriana Santodomingo,&nbsp;Richard Thomas,&nbsp;Sebastián Muñoz-Leal,&nbsp;Gerardo Acosta-Jamett","doi":"10.1155/tbed/8841276","DOIUrl":"https://doi.org/10.1155/tbed/8841276","url":null,"abstract":"<div>\u0000 <p>Tick-borne spirochetes of the genus <i>Borrelia</i> are maintained in enzootic transmission cycles involving wild vertebrates such as rodents. The genus includes the lyme disease group (LDG), transmitted by hard ticks (Ixodidae), and the relapsing fever group (RFG), mostly transmitted by soft ticks (Argasidae). While research on <i>Borrelia</i> spirochetes has been largely concentrated in the Northern Hemisphere, recent studies have uncovered new genospecies in South American ecosystems. Particularly in Chile, while <i>Borrelia chilensis</i> is the sole species that has been cultured, multiple under characterized strains have been detected in wild rodents and ticks. This study aimed to genetically characterize strains of <i>Borrelia</i> in ticks parasitizing <i>Phyllotis darwini</i>, an abundant rodent species inhabiting the central north of the country. From 2021 to 2023, rodents were captured at two sites in the Coquimbo Region. Observed ticks were collected, morphologically identified, and submitted to DNA extraction to further detect the presence of <i>Borrelia</i> spirochetes through nested PCR targeting the <i>flaB</i> gene. Multilocus sequence typing (MLST) of eight housekeeping genes was subsequently performed on positive samples. Pairwise nucleotide comparisons and phylogenetic analyses with the retrieved sequences were conducted using maximum likelihood (ML) and Bayesian inference (BI) methods. A total of 634 <i>P. darwini</i> were captured, yielding 134 ticks, all identified as <i>Ixodes</i> spp. Ten ticks genetically identified as <i>Ixodes abrocomae</i> or <i>Ixodes sigelos</i> tested positive for <i>Borrelia</i> spp. Genetic identity and phylogenetic analyses revealed the presence of two novel LDG genospecies in Chile, where <i>B. chilensis</i> was the sole previously known species of the group. Although the vectors and pathogenic roles of these novel genospecies are currently unknown, our study underscores the need for further isolation attempts of the strains to assess their impact on wildlife or human health.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/8841276","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144598773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Pathogenicity of PCV2, PCV3, and PCV4 in Piglets: Insights Into Clinical, Pathological, and Immunological Features","authors":"Jiawei Zheng,&nbsp;Xue Li,&nbsp;Xinru Lv,&nbsp;Yaqi Han,&nbsp;Xinwei Zhang,&nbsp;Si Chen,&nbsp;Fuxian Zhang,&nbsp;Linzhu Ren","doi":"10.1155/tbed/6362100","DOIUrl":"https://doi.org/10.1155/tbed/6362100","url":null,"abstract":"<div>\u0000 <p>Porcine circoviruses (PCVs) have been a significant concern in swine health, with PCV2 being a well-established pathogen. However, the newly discovered PCV3 and PCV4 have emerged, and their impact on piglets remains less understood. Understanding their pathogenicity is crucial for effective porcine health management. In this study, 3-week-old piglets were inoculated with PCV2, PCV3, and PCV4. PCV2 led to expected growth inhibition and severe clinical signs like anorexia. PCV3, though showing milder symptoms, exhibited unique tissue tropism, with detectable virus in the heart, lungs, and brain tissues. PCV4 caused distinct tissue damage, including cardiac fibrosis and renal changes. In terms of immune responses, each virus triggered different cytokine profiles. PCV3 and PCV4 also demonstrated replication capabilities in vitro and in vivo. PCV3 and PCV4 clearly have pathogenic patterns that differ from those of PCV2. These findings provide essential insights for veterinarians and swine producers. Understanding these viruses’ behavior aids in developing targeted prevention and control strategies, such as improved diagnostic tools and potential new vaccines, to enhance porcine health management and safeguard the swine industry from the threats posed by these emerging PCVs.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/6362100","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144589679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Report of Anaplasma phagocytophilum in Galapagos: High Prevalence in Dogs and Circumstantial Evidence for the Role of Rhipicephalus linnaei as Vector","authors":"Carla Andreea Culda,&nbsp;Luciana Cătălina Panait,&nbsp;Cristina Daniela Cazan,&nbsp;Hein Sprong,&nbsp;Rommel Lenin Vinueza,&nbsp;Diego Páez-Rosas,&nbsp;Renato Leon,&nbsp;Andrei Daniel Mihalca","doi":"10.1155/tbed/5542334","DOIUrl":"https://doi.org/10.1155/tbed/5542334","url":null,"abstract":"<div>\u0000 <p>The current study investigates the presence and prevalence of <i>Anaplasma</i> species in dogs from the Galapagos Islands, focusing on the potential vectorial role of <i>Rhipicephalus linnaei</i> in the transmission of these pathogens. Blood samples were collected from 1221 dogs across four islands, with tick collections for morphological and genetic identification. The results revealed a significant molecular prevalence of <i>Anaplasma phagocytophilum</i> (20.3%), predominantly in Santa Cruz (35.16%) and Isabela (18.9%), while <i>A. platys</i> was identified in 2.9% of samples. Genetic analysis identified the presence of <i>A. phagocytophilum</i> ecotype I, aligning more closely with European strains. Furthermore, <i>R. linnaei</i> was confirmed as the only tick species associated with dogs, suggesting its role as a vector for both <i>A. phagocytophilum</i> and <i>A. platys</i>. This study marks the first molecular confirmation of these pathogens in the Galapagos, contributing with important insights into the epidemiology of tick-borne diseases in this ecosystem. The findings highlight the need for improved surveillance and control to reduce the risk and further spread of these tick-borne diseases.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/5542334","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence of Methicillin-Resistant Staphylococcus aureus (MRSA) in Egyptian Water Buffaloes and Risk Factors for Subclinical Mastitis","authors":"Abdelfattah Selim,&nbsp;Mohamed Marzok,&nbsp;Hattan S. Gattan,&nbsp;Abdelrahman M. Hereba","doi":"10.1155/tbed/8862271","DOIUrl":"https://doi.org/10.1155/tbed/8862271","url":null,"abstract":"<div>\u0000 <p><i>Staphylococcus aureus</i> (<i>S. aureus</i>) is one of the main causative agents of mastitis, which results in severe economic losses. In addition, methicillin-resistant <i>S. aureus</i> (MRSA) has been reported in dairy farms and in water buffaloes. The present study aimed to determine the prevalence of subclinical mastitis (SCM) in water buffaloes, associated risk factors for SCM, and prevalence of MRSA in positive milk samples for SCM. Milk samples (<i>n</i> = 385) from buffaloes were examined using the California mastitis test (CMT), and <i>S. aureus</i> was detected in positive milk samples using bacteriological and biochemical tests. In addition, MRSA was identified in positive <i>S. aureus</i> samples using PCR targeting the <i>mecA</i> gene. The results revealed that the prevalence of SCM among water buffaloes in the studied areas was 43.6%, and 61.9% (104/168) were identified as MRSA based on PCR targeting the <i>mecA</i> gene. In vitro antibiotic susceptibility testing found cefoxitin to be resistant and linezolid to be sensitive against MRSA isolates. In addition, the statistical analysis revealed that there was no significant association between the prevalence of SCM and locality or duration of lactation. The prevalence of SCM was strongly associated with age, parity, absence of teat dipping, hand cleaning of milker hands between milking, and in animals with a history of mastitis. Regular CMT can detect early SCM and improve udder sanitation and milking hygiene. In addition, continuous testing of antimicrobial drugs against MRSA isolates is necessary due to the importance of <i>S. aureus</i> in public health and the development of antibiotic resistance, such as methicillin.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/8862271","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144524504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproductive Pathogenic Characteristics of a Highly Virulent Porcine Reproductive and Respiratory Syndrome Virus L1J (Lineage Korean Clade C) in Gilts","authors":"Jeongmin Suh,&nbsp;Chanhee Chae","doi":"10.1155/tbed/1172597","DOIUrl":"https://doi.org/10.1155/tbed/1172597","url":null,"abstract":"<div>\u0000 <p>Porcine reproductive and respiratory syndrome virus (PRRSV) remains a major challenge to swine health and production globally. Among PRRSV-2 lineages circulating in South Korea, the lineage 1J (L1J)—recently reclassified from lineage Korean clade C (LKC)—has emerged as an epidemiologically significant variant, accounting for approximately 15%–28.9% of cases in recent years. Despite its widespread circulation, data on the reproductive pathogenicity of L1J strains remain scarce. To address this gap, an experimental infection study was conducted to evaluate the reproductive pathogenicity of PRRSV strain SNUVR220803 in pregnant gilts. This strain, originally classified within L1J and is characterized by multiple recombination events with lineage 5 viruses-presumably the Ingelvac PRRS MLV vaccine strain, as well as a unique four-amino acid deletion in Nsp2. Eight PRRSV-naïve pregnant gilts at 86 days of gestation were randomly assigned to either the infected (<i>n</i> = 4) or control (<i>n</i> = 4) group. Inoculated gilts exhibited elevated rectal temperatures at 2 days postinoculation (dpi), followed by clinical signs including anorexia and lethargy between 7 and 10 dpi. Clinical recovery was observed by 14 dpi; however, all infected gilts subsequently experienced abortion or premature farrowing at gestational days 109–112, during which no viable piglets were recovered, except for two that died within 30 min after birth without trauma, indicating intrauterine death or severe neonatal compromise. These findings demonstrate that SNUVR220803 possesses markedly higher reproductive pathogenicity than previously reported L1J strains, such as K07-2273. Given that PRRSV reproductive virulence cannot be fully explained by ORF5-based classification alone, the heightened pathogenicity of SNUVR220803 is likely attributed to a combination of mutations in nonstructural and structural proteins. These results highlight the need for continued molecular surveillance and pathogenicity studies of emerging PRRSV strains.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/1172597","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144520101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On-Site Rapid and Specific Detection of Novel Emerging Goose Astrovirus Using a Nanobody-Based Colloidal Gold Immunochromatographic Strip","authors":"Dan Wang,&nbsp;Yanhong Ji,&nbsp;Bin Liu,&nbsp;Lihuan Yan,&nbsp;Yi Ai,&nbsp;Jing Wang,&nbsp;Tao Jiang,&nbsp;Mi Lin,&nbsp;Qiyun Zhu","doi":"10.1155/tbed/6439771","DOIUrl":"https://doi.org/10.1155/tbed/6439771","url":null,"abstract":"<div>\u0000 <p>In recent years, outbreaks of gouty goose disease in goslings caused by a novel goose astrovirus (nGAstV) have occurred across major poultry-producing regions in Eastern China, with a mortality rate of approximately 50%. To date, there is a lack of rapid detection kits for early-stage disease control to reduce economic losses. In this study, two nanobodies (Nb-58 and Nb-60) that reacted with the nGAstV P2 protein were screened and identified using phage display technology and immunological experiments to develop colloidal gold immunochromatographic strips (CGISs) for nGAstV detection. CGIS did not cross-react with goose parvovirus (GPV), goose circovirus (GCV), H9N2 avian influenza virus (H9N2 AIV), Newcastle disease virus (NDV), avian leukemia virus (ALV), or infectious bursal disease virus (IBDV), indicating its strong specificity. The detection threshold of the CGIS was more than 640-fold diluted nGAstV (~10^1.57 TCID₅₀), which was comparable to a Ct value of 26.82, thereby showing high sensitivity. CGIS, with high stability, could be stored for at least 6 months at 25 and 4°C. The repeatability test showed that nGAstV could be readily detected in different CGIS batches. The coincidence rates of CGIS and conventional reverse transcription-polymerase chain reaction (RT-PCR) in 51 clinical tissue samples and 60 cloacal swab samples were 100% and 95.24%, respectively. In conclusion, the present study identified two specific Nbs and developed a reliable CGIS for the rapid detection of nGAstV in the field setting.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/6439771","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Replication and Virulence in Cattle of the First Lumpy Skin Disease Virus Isolated in Xinjiang, China (2019)","authors":"Minmin Zhang,&nbsp;Shaohan Li,&nbsp;Yujie Shi,&nbsp;Xiaolong Xu,&nbsp;Zhiyuan Wen,&nbsp;Jinying Ge,&nbsp;Qiwei Zhang,&nbsp;Xinyin Lu,&nbsp;Xin Yin,&nbsp;Zhigao Bu","doi":"10.1155/tbed/2315442","DOIUrl":"https://doi.org/10.1155/tbed/2315442","url":null,"abstract":"<div>\u0000 <p>Before 2012, lumpy skin disease (LSD) was primarily confined to African countries. However, it rapidly spread to the Middle East and Southeast Europe, reaching the Balkans, the Caucasus, and the Russian Federation by 2015. The first confirmed case in China was reported on August 10, 2019, in Yili, Xinjiang, and on August 26, the Chinese government officially notified the World Organization for Animal Health (WOAH) of the outbreak. In this study, we isolated a LSD virus (LSDV) strain from a severely affected cattle skin sample collected in the Yili region of Xinjiang and designated it as strain Xinjiang/2019. Next-generation sequencing (NGS) analysis revealed that strain Xinjiang/2019 shared the highest similarity with the LSDV/Russia/Saratov/2017 strain based on full-length LSDV sequences available in NCBI. Phylogenetic analysis revealed that the Xinjiang/2019 isolate clustered with strains from China, Vietnam, Thailand, and Indonesia, forming a distinct phylogenetic branch. Recombination analysis further indicated that Xinjiang/2019 is predominantly a recombinant strain, derived from South African and European strains. To assess pathogenicity, cattle were infected with strain Xinjiang/2019 via intravenous (Group I) or intradermal (Group II) injection. In Group I, four out of five animals developed typical LSD symptoms, including fever (day 7), secondary nodules (day 8), rhinitis, conjunctivitis, and lymph node enlargement. Group II showed viremia by day 5 with milder symptoms. These findings indicate that strain Xinjiang/2019 is a virulent strain responsible for the first LSD outbreak in China.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/2315442","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144525042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation, Passage, and Pathogenicity of a Newly Isolated Lawsonia intracellularis Strain From Hubei, China","authors":"Rui Xie,&nbsp;Yajuan Luo,&nbsp;Changjiang Peng,&nbsp;Wenqing Wu,&nbsp;Yucong Cui,&nbsp;Xinru Sun,&nbsp;Lin Hua,&nbsp;Bin Wu,&nbsp;Zhong Peng","doi":"10.1155/tbed/2501719","DOIUrl":"https://doi.org/10.1155/tbed/2501719","url":null,"abstract":"<div>\u0000 <p><i>Lawsonia intracellularis</i> is the causative agent of porcine proliferative enteropathy (PPE)—a disease of great economic impact to the global pig industry, but the isolation and continuous passage culture of this bacterial species is very difficult which limits the development of inactivated or live vaccines. While China is the largest pig rearing country in the world, only one study has reported the isolation of <i>L</i>. <i>intracellularis</i>. In this study, we examined 1574 ileal samples collected from 10 slaughterhouses in Hubei Province, China, and obtained 104 samples tested positive for <i>L. intracellularis</i>. From these positive samples, we successfully isolated a <i>L. intracellularis</i> strain designated LI-HuB23, which could be continuously passaged in IEC-18 cells. The successful isolation of LI-HuB23 was confirmed by transmission electron microscopy (TEM), indirect immunofluorescence assay (IFA), PCR amplifying, and Sanger sequencing of the marker gene (<i>aspA</i>). LI-HuB23 exhibited stable proliferation over 10 passages and it was still being passaged for over 30 generations. Oral inoculation of 28-day-old pigs with LI-HuB23 containing 6.9 × 10⁸ bacterial microorganisms induced loose stools and watery diarrhea between Days 14 and 28 postinfection. Challenging pigs showed an average daily gain (ADG) lowered than the control pigs (206.05 ± 23.48 g/day vs. 241.43 ± 16.78 g/day). All challenging were serologically positive for <i>L. intracellularis</i> IgG at 21 days postinoculation. Histological examination detected crypt hyperplasia, characterized by a reduction in goblet cells within the hyperplastic crypts. Colonization of <i>L. intracellularis</i> in ileal crypts was confirmed by immunohistochemical examination.</p>\u0000 </div>","PeriodicalId":234,"journal":{"name":"Transboundary and Emerging Diseases","volume":"2025 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/tbed/2501719","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}