To clarify the genetic evolutionary characteristics of porcine reproductive and respiratory syndrome virus (PRRSV) circulating in northern Xinjiang, China, in 2026, this study employed third-generation sequencing technology to determine the complete genome sequences of locally prevalent PRRSV strains and conducted systematic analyses of their molecular features. Porcine serum samples were collected from pig farms in northern Xinjiang, China, in 2026, and four PRRSV-2-positive samples were identified via fluorescent RT-PCR. Whole-genome sequencing was performed using the CycloneSEQ nanopore single-molecule sequencing platform. After obtaining the complete viral genome sequences, bioinformatics software including MEGA 12, DNASTAR, RDP4, and SimPlot 3.5.1 were used for phylogenetic analysis, homology comparison, key amino acid variation analysis, and recombination event identification. One high-quality complete PRRSV-2 genome sequence, designated XJ/PRRSV-2/2026-1 (15,009 bp in full length), was successfully obtained, along with three additional low-quality sequences used as references. Phylogenetic analysis revealed that all sequences belonged to Sublineage 1.8 (NADC30-like) of PRRSV-2. Homology analysis revealed that this strain shared the highest nucleotide identity (87.5%) with the NADC30 reference strain, with the ORF1a gene exhibiting the most significant variation, particularly within the NSP2 region. Amino acid sequence alignment revealed that the NSP2 region exhibits a discontinuous deletion pattern of "111 + 2+1 + 19", characterized by an additional two-amino-acid deletion at positions 467-468 compared to the typical "111 + 1+19" deletion of NADC30-like strains. Amino acid variations in the GP5 protein were concentrated in the signal peptide region (aa 1-31) and the C-epitope region (aa 53-62), containing three potential N-glycosylation sites (34 NSSS, 44 NLTI, 51 NGTD) and two transmembrane regions. Recombination analysis confirmed that this strain is a recombinant strain derived from NADC30, JXA1, and ATCC VR-2332, with three recombination breakpoints identified. This study presents a whole-genome characterization of an NADC30-like recombinant PRRSV strain detected from northern Xinjiang, China. A novel NSP2 deletion pattern and critical amino acid substitutions in the GP5 protein were identified. These observations are consistent with previous regional molecular epidemiological surveillance and may serve as a basis for broader investigations into the genetic evolution of PRRSV.
Shuhua Liu, Zhen Zhang, Baihe Ma et al.· Microbial Pathogenesis· 0 citations
Avian coccidiosis, caused by Eimeria spp., remains a major parasitic disease of poultry and imposes significant economic burdens on the global poultry industry. This review systematically synthesizes key advances over the past decade concerning host-Eimeria interactions, molecular regulatory mechanisms, and novel control strategies, while contextualizing these findings with earlier seminal discoveries. In recent years, novel diagnostic tools based on molecular detection and antigen capture have emerged, offering improved sensitivity and interspecies specificity over conventional methods. These techniques complement traditional approaches relying on oocyst morphology and histopathology, and provide critical support for accurate assessment of field infection status, species and genotype discrimination, monitoring of drug-sensitivity shifts, and elucidation of transmission dynamics. Epidemiological investigations have further revealed the impacts of rearing management, environmental temperature and humidity, host genetic background, and gut microbiota composition on infection kinetics, underscoring the necessity of integrating biosecurity and precision management into regionally tailored control programs. Utilizing chicken embryo and chick infection models, in conjunction with CRISPR/Cas9 gene editing, single-cell transcriptomics, and high-resolution proteomics, researchers have gained deeper insights into key regulatory genes governing invasion, asexual multiplication, and gametogenesis, as well as invasion-related effector molecules and resistance-associated markers, thereby laying a foundation for the identification of novel intervention targets. In immunology, growing knowledge of the intestinal epithelial barrier response, Th1/Th17 polarization, regulatory T-cell function, and immune evasion strategies (e.g., antigenic variation and downregulation of host antigen presentation) provides a theoretical basis for the rational optimization of subunit vaccines and live oocyst vaccines. On the therapeutic front, novel combination regimens of conventional anticoccidials and plant-derived bioactive compounds have shown efficacy in reducing oocyst shedding and alleviating intestinal lesions, while nanoparticle-based targeted delivery systems and adjuvant combination strategies are being explored to enhance drug bioavailability or vaccine-induced protective immunity. Nevertheless, the effective integration of ever-expanding omics data, immune-protective mechanisms, and field-applicable control measures, while concurrently addressing drug residues and resistance management, remains a central challenge for achieving sustainable coccidiosis control.