Capripox viruses are economically important pathogens in goat and sheep producing areas of the world, with specific focus on goat pox virus (GTPV), sheep pox virus (SPPV) and the Lumpy Skin Disease virus (LSDV). Clinically, sheep pox and goat pox have the same symptoms and cannot be distinguished serologically. This presents a real need for a rapid, inexpensive, and easy to operate and maintain genotyping tool to facilitate accurate disease diagnosis and surveillance for better management of Capripox outbreaks. A LAMP method was developed for the specific differential detection of GTPV and SPPV using three sets of LAMP primers designed on the basis of ITR sequences. Reactions were performed at 62°C for either 45 or 60 min, and specificity confirmed by successful differential detection of several GTPV and SPPV isolates. No cross reactivity with Orf virus, foot-and-mouth disease virus (FMDV), A. marginale Lushi isolate, Mycoplasma mycoides subsp. capri, Chlamydophila psittaci, Theileria ovis, T. luwenshuni, T. uilenbergi or Babesia sp was noted. RFLP-PCR analysis of 135 preserved epidemic materials revealed 48 samples infected with goat pox and 87 infected with sheep pox, with LAMP test results showing a positive detection for all samples. When utilizing GTPV and SPPV genomic DNA, the universal LAMP primers (GSPV) and GTPV LAMP primers displayed a 100% detection rate; while the SPPV LAMP detection rate was 98.8%, consistent with the laboratory tested results. In summary, the three sets of LAMP primers when combined provide an analytically robust method able to fully distinguish between GTPV and SPPV. The presented LAMP method provides a specific, sensitive and rapid diagnostic tool for the distinction of GTPV and SPPV infections, with the potential to be standardized as a detection method for Capripox viruses in endemic areas.

Goatpox virus (GTPV) and sheeppox virus (SPPV), which belong to the Capripoxvirus (CaPV), are economically important pathogens of small ruminants. Therefore, a sensitive, specific and rapid diagnostic assay for detection of GTPV and SPPV is necessary to accurately and promptly control these diseases. Recombinase polymerase amplification (RPA) assays combined with a real-time fluorescent detection (real-time RPA assay) and lateral flow dipstick (RPA LFD assay) were developed targeting the CaPV G-protein-coupled chemokine receptor (GPCR) gene, respectively. The sensitivity of both CaPV real-time RPA assay and CaPV RPA LFD assay were 3 × 102 copies per reaction within 20 min at 38 °C. Both assays were highly specific for CaPV, with no cross-reactions with peste des petits ruminants virus, foot-and-mouth disease virus and Orf virus. The evaluation of the performance of these two assays with clinical sample (n = 107) showed that the CaPV real-time RPA assay and CaPV RPA LFD assay were able to specially detect SPPV or GTPV present in samples of ovine in liver, lung, kidney, spleen, skin and blood. This study provided a highly time-efficient and simple alternative for rapid detection of GTPV and SPPV.

Clinically, sheeppox and goatpox have the same symptoms and cannot be distinguished serologically. A cheaper and easy method for differential diagnosis is important in control of this disease in endemic region. A duplex PCR assay was developed for the specific differential detection of Goatpox virus (GTPV) and Sheeppox virus (SPPV), using two sets of primers based on viral E10R gene and RPO132 gene. Nucleic acid electrophoresis results showed that SPPV-positive samples appear two bands, and GTPV-positive samples only one stripe. There were no cross-reactions with nucleic acids extracted from other pathogens including foot-and-mouth disease virus, Orf virus. The duplex PCR assay developed can specially detect SPPV or GTPV present in samples (n = 135) collected from suspected cases of Capripox. The duplex PCR assay developed is a specific and sensitive method for the differential diagnosis of GTPV and SPPV infection, with the potential to be standardized as a detection method for Capripox in endemic areas.

Background: Pseudorabies virus (PRV) is a highly infectious pathogen that affects a wide range of mammals and imposes a significant economic burden on the global pig industry. The viral envelope of PRV contains several glycoproteins, including glycoprotein E (gE) and glycoprotein B (gB), which play critical roles in immune recognition, vaccine development, and diagnostic procedures. Mutations in these glycoproteins may enhance virulence, highlighting the need for updated vaccines. Method: This review examines the functions of PRV gE and gB in vaccine development and diagnostics, focusing on their roles in viral replication, immune system interaction, and pathogenicity. Additionally, we explore recent findings on the importance of gE deletion in attenuated vaccines and the potential of gB to induce immunity. Results: Glycoprotein E (gE) is crucial for the virus’s axonal transport and nerve invasion, facilitating transmission to the central nervous system. Deletion of gE is a successful strategy in vaccine development, enhancing the immune response. Glycoprotein B (gB) plays a central role in viral replication and membrane fusion, aiding viral spread. Mutations in these glycoproteins may increase PRV virulence, complicating vaccine efficacy. Conclusion: With PRV glycoproteins being essential to both vaccine development and diagnostic approaches, future research should focus on enhancing these components to address emerging PRV variants. Updated vaccines and diagnostic tools are critical for combating new, more virulent strains of PRV.

Vaccination with inactivated whole-virus vaccines remains the most effective measure for controlling foot-and-mouth disease virus (FMDV) transmission and d

Recently, serotype O foot-and-mouth disease viruses (FMDVs) belonging to four lineages (O/ME-SA/PanAsia, O/ME-SA/Ind2001, O/SEA/Mya-98, and O/Cathay) co-circulate in China, and the emergence of new variant viruses belonging to the Cathay lineage renders the existing vaccines less effective, which poses a serious threat to the livestock industries. The surface-exposed G-H loop of the VP1 structural protein of FMDV plays an important role in inducing neutralizing antibodies, generation of antigenic variants, and virus attachment. Here, we generated three recombinant FMDVs in which the G-H loops have been substituted with the corresponding sequences from the circulating strains of the PanAsia, Mya-98, and Cathay lineages based on an infectious cDNA clone of a chimeric FMDV, which carries amino acid substitutions in the leader protein and all surface proteins of FMDV O/XJ/CHA/2017. All mutant viruses exhibited a significantly improved replication capacity in BHK-21 cells and displayed relatively larger plaque morphologies compared with the parental virus. Chemically inactivated vaccines prepared from the parental virus and the mutant viruses all induced protective liquid-phase blocking ELISA (LPBE) antibodies against FMDVs in pigs after 28 days post vaccination (dpv), but only the vaccine with the substitution of the G-H loop of the Cathay strain induced protective neutralizing antibodies against the viruses of four lineages, while other vaccines exhibited excellent immunological cross-reactivity to the viruses of Ind2001, PanAsia, and Mya-98 lineages but did not for the Cathay virus at 28 dpv. Our studies indicated that the G-H loop of the Cathay virus plays a critical role in the antigenic drift of FMDV, which will provide key insights for designing porcinophilic FMDV vaccines in the future. Key points • The swapping of the G-H loops of FMDVs notably improved replication capacity of FMDV in BHK-21 cells. • The swapping of the G-H loop of the Cathay virus obviously broadens antigenic coverage of FMDV vaccine. • The study showed that the G-H loop of the Cathay virus plays a critical role in antigenic drift of FMDV.