Foot-and-mouth disease: past, present and future

Global foot-and-mouth disease risk assessment based on multiple spatial analysis and ecological niche model

Foot-and-Mouth Disease is a highly contagious transboundary animal disease. FMD has caused a significant economic impact globally due to direct losses and trade restrictions on animals and animal products. This study utilized multi-distance spatial cluster analysis, kernel density analysis, directional distribution analysis to investigate the spatial distribution patterns of historical FMD epidemics. A multi-algorithm ensemble model considering climatic, geographic, and social factors was developed to predict the suitability area for FMDV, and then risk maps of FMD for each species of livestock were generated in combination with the distribution of livestock. The results show that all serotypes of FMD exhibit significant clustering with a clear tendency toward a directional distribution. Serotypes A and O are widespread in Asia, Europe, Africa, and South America. Serotype Asia 1 is prevalent in Asia. Serotype SAT2 is prevalent in Africa and the Middle East, while Serotypes SAT1 and SAT3 are restricted to Africa. Ecological niche modeling reveals temperature, precipitation, wind speed, and vegetation are important factors influencing the occurrence of FMD. Except for buffaloes, the distribution of high-risk areas for FMD occurrence in other livestock species is quite widespread. The areas primarily include the southern region of North America, the northern, southern, and eastern regions of South America, the Mediterranean region, the eastern region of Europe, the central and southern regions of Africa, the central, eastern, and southern regions of Asia, and parts of Australia. These findings will provide valuable insights into the prevention and control of FMD.

Productivity, reproduction and economic losses due to foot-and-mouth disease (FMD) in Iranian Holstein cows

This retrospective study investigated the impact of foot-and-mouth disease (FMD) on productive and reproductive traits, economic losses and culling trends in Holstein cows in Iran. Data from nine industrial and semi-industrial dairy herds from several provinces were analyzed over a decade (2009-2019) and included a total of 49,400 records from 20,330 cows. A mixed linear model was used to assess the impact of FMD on milk production, fat and protein yields and reproductive traits. Information on milk production was collected over a period of 305 d. A simulated bioeconomic model was used to estimate the financial losses due to FMD incidence on productive and reproductive traits. The model included losses due to reduced milk production, discarded milk, reproductive inefficiency, morbidity, culling and replacement animals, loss of body weight, vaccination, medication and supplementation costs, and labor costs. FMD significantly reduced milk production, with an average decrease of 845.9 kg of fat corrected milk (FCM) per cow, a decrease of 44.1 kg in fat yield and a decrease of 2.3 kg in protein yield. Reproductive performance was negatively affected, with an increase in calving interval (+30.9 day), days open (+13.7 day), number of inseminations (+0.2-fold) and length of gestation (+1 day). Economic analysis showed an average loss of $1082.3 per FMD case, with the highest costs attributable to culling and replacement of animals (27 %, $296.2) and reproductive inefficiency (22 %, $239.6). These results have significant implications for farm management strategies to control the spread of FMD and to plan preventative measures to reduce economic losses.

Common host factors for internal ribosomal entry site-mediated translation of viral genomic RNA: An investigation in foot-and-mouth disease and classical swine fever viruses

We previously proposed polycystic kidney disease1-like 3 (PKD1L3) and ubiquitin-specific peptidase 31 (USP31) as potential common host factors for IRES-mediated RNA translation in infections with foot-and-mouth disease virus (FMDV) and classical swine fever virus (CSFV). However, those findings required substantiation, and the specific roles of these factors in the IRES-mediated translation remained unclear. Accordingly, in this study, we aimed to confirm the roles of PKD1L3 and USP31 as host factors associated with IRES activity in bi-cistronic reporter assays, and to investigate the interactions of these host proteins during IRES activity. PKD1L3 and USP31 silencing suppressed IRES activity in both FMDV and CSFV RNAs. PKD1L3 and USP31 overexpression had no significant effects. PKD1L3 and USP31 silencing also suppressed viral RNA replication for CSFV and infection with another picornavirus (from the same family as FMDV), encephalomyocarditis virus. Immunoprecipitation assays revealed that PKD1L3 and USP31 can interact with each other. We also examined their interaction with a eukaryotic translation factor involved in the IRES of hepatitis C virus (HCV), eIF3c. PKD1L3 and more pronouncedly USP31 can interact with eIF3c. Immunofluorescent assays revealed partial, cytoplasmic co-localization of USP31 with PKD1L3, eIF3c, and Hsp90β. Moreover, silencing of eIF3c and Hsp90β suppressed FMDV- and CSFV-IRES activity. Our results indicate the possibility that PKD1L3 and USP31 can participate in IRES activity by interacting with eIF3c and Hsp90β.

Foot-and-mouth disease virus 3C protein acts as an anti-inflammatory factor by mediating degradation of TLR4 signaling various molecules via caspase activity

During the early stages of foot-and-mouth disease virus (FMDV) infection, a series of acute inflammatory responses occur in the host. As the disease progresses, these inflammatory responses gradually weaken until the host is nearly recovered. However, the mechanism by which FMDV participates in the negative regulation of host inflammatory responses remains unclear. In this study, we found that FMDV 3C plays a crucial role in inhibiting the inflammatory response by degrading various molecules in the TLR4 signaling pathway. Mechanistically, we discovered that this degradation is mediated by caspase activity, which is activated by 3C protease. Specifically, FMDV 3C targets TLR4, TRIF, p65, IRF3, and TBK1 for degradation through caspase-3, and degrades IRF3 and TBK1 via caspase-8. Notably, FMDV 3C targets TBK1 for degradation through caspase-3, caspase-8, and caspase-9 independently. In conclusion, this is the first report identifying FMDV 3C as an anti-inflammatory factor that mediates the degradation of various molecules to inhibit TLR4 signaling through caspase activity. This study provides a novel insight into explore the relationship between FMDV and inflammation and offers ideas for exploring the biological function of 3C and the pathogenesis of FMDV.

Elucidating the structural dynamics induced by active site mutations in 3C protease of foot-and-mouth disease virus

The viral replication of foot-and-mouth disease virus (FMDV) and other picornaviruses primarily depends on the successful processing of a polyprotein precursor by the enzyme 3C protease (3Cpro) at specific sites. The crucial role of 3Cpro in viral replication and pathogenesis makes it a potential target for developing novel therapeutics against foot-and-mouth disease. The β-ribbon region (residues 138-150) containing the active site residues (C142) in 3Cpro is found to be conserved and contributes significantly to substrate specificity. Moreover, experimental reports suggest that mutations at position 142, particularly C142S and C142L, exhibit different functional activities. However, the intrinsic dynamics and conformational changes induced by active-site mutations of 3Cpro remain unclear, limiting the development of novel inhibitors of 3C protease. Accordingly, we carried out molecular dynamics (MD) simulations with multiple replicates for both the WT and mutants of 3Cpro. The observed results suggest that the C142S mutant induces substantial structural transitions compared to the WT and C142L. In contrast, the essential dynamics of the mutants significantly varied from those of the WT 3Cpro. Moreover, cross-correlation analysis revealed a similar pattern of anti-correlation between the amino acid residues of the WT and C142L mutant complexes. Analysis of the betweenness centrality of the WT and the mutants from the residue interaction networks revealed common residues for intra-residual signal propagation. The results from our study suggest that the active site mutant C142S may induce conformational changes, which can cause the β-ribbon region to bend towards the catalytic pocket and inhibit the enzymatic activity. C142L substitution may also alter the β-ribbon region conformation, which may impact the substrate binding process during proteolysis, as reported in previous studies. These results can provide a better understanding of the conformational dynamic behavior of 3Cpro active-site mutants and may assist in developing potential inhibitors against foot-and-mouth disease.

Age- and agro-climatic zone-specific variations in post-vaccinal antibody responses to FMD vaccination in bovine populations: a longitudinal study from Karnataka, India

This longitudinal study examined variations in post-vaccination antibody response to Foot-and-Mouth Disease (FMD) vaccination in bovines across different age groups and agro-climatic zones in Karnataka, India. A total of 374 serum samples were collected from 28 villages across nine agroclimatic zones, targeting pre- and post-vaccination titers for FMD virus serotypes O, A, and Asia-1. Analysis via single-dilution liquid-phase blocking ELISA revealed significant findings: pre-vaccination immune proportions were below the herd immunity threshold (< 80%) for serotypes O and Asia-1 but exceeded it for serotype A. Younger bovines (< 24 months) displayed notably lower antibody titers (log₁₀1.67-1.99) compared to older cattle (> 24 months; log₁₀2.14-2.44), highlighting the age-dependent vaccine response variability. Agroclimatic disparities were evident, with regions like the Coastal and Central Dry Zones failing to achieve protective titers (log₁₀<1.8) even post-vaccination, whereas zones like the Eastern Dry Zone demonstrated marked improvements. Post-vaccination seromonitoring showed an overall increase in immune proportions for all serotypes, yet younger cattle and certain agroclimatic zones remained suboptimal. These findings emphasize the importance of region-specific vaccination strategies and the need for tailored booster protocols to enhance immunity in younger bovines. The study underscores the utility of seromonitoring in optimizing FMD control programs by addressing age and agro-climatic disparities in immune responses.

Evaluation of the immune effect of foot-and-mouth disease virus-like particles derived from Pichia Pastoris on mice and pigs

Foot-and-mouth disease (FMD) is an acute, highly contagious, infectious disease that affects cloven-hoofed animals and the healthy development of animal husbandry. Despite the pivotal role of the inactivated FMD vaccine in preventing and controlling the disease, the production and preparation of the inactivated vaccine still present certain safety concerns. Virus-like particles (VLPs), which have a shell structure similar to that of the viruses but lack the genetic material of viruses, have emerged as a prominent area of research on developing next-generation FMD vaccines. In this study, co-expression of P1 and 3C was implemented to obtain the capsid protein of FMD virus (FMDV), and VLPs of FMD were prepared using Pichia Pastoris. Given that the enzymatic activity of 3C is not ideal in acidic yeast cells, the HLH pattern structure was added to the N-terminal end of 3C, which can be anchored near the exit of the nascent peptide chain of ribosomes. Furthermore, the alcohol oxidase (AOX) promoter, which regulates the expression of 3C, was enhanced by mutation. Then, FMDV VLPs were successfully produced in yeast. Immunization of mice and pigs with VLPs resulted in high levels of specific and neutralizing antibodies and provided protection against FMDV in pigs. In conclusion, FMDV VLPs can be successfully produced in P. Pastoris. This offers a new way to develop FMDV VLP vaccines.

Molecular Characterization and Genetic Diversity of Isolated Foot-and-Mouth Disease Viruses Circulating in Cattle in The Mekong Delta Provinces, Vietnam

Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-footed livestock caused by foot-and-mouth disease virus (FMDV). FMD has significant impacts on farmers and national economies. The evolution and mutation of FMDV have contributed to the emergence of new strains of FMDV. Sequences of VP1 from 11 FMDV isolates in the Mekong Delta Provinces were obtained by Sanger sequencing technology. The phylogenetic analysis of VP1 sequence elucidated that 8 FMDV isolates including O-VN-CTU-VL01 (PP897837), O-VN-CTU-VL02 (PP897838), O-VN-CTU-TV01 (PP897840), O-VN-CTU-TV02 (PP897841), O-VN-CTU-TV03 (PP897842), O-VN-CTU-TV04 (PP897844), O-VN-CTU-BT04 (PP897847), and O-VN-CTU-BT05 (PP897847) were clustered into Group 1. On the other hand, 3 FMDV isolates including O-VN-CTU-BT01 (PP897844), O-VN-CTU-BT02 (PP897844), and O-VN-CTU-BT03 (PP897844) were clustered into Group 2. In addition, the nucleotide and deduced amino acid sequences of VP1 in Group 1 were closely related to lineage Mya-98, topotype SEA, and Type O (89%-93% nucleotide identity and 91%-99% amino acid identity). The similarity of FMDV isolates in Group 2 was closely related to lineage Pan Asia, topotype ME-SA, Type O (91.13%-94.53% and 96%-99.44% nucleotide and amino acid similarities, respectively). Analysis of amino acid sequences of VP1 illustrated several substitution mutations detected at amino acid positions 133-158 (the main antigenic site) in lineages Mya-98 (O/SEA) and Pan Asia, (O/ME-SA). Notably, a substitution mutation at position M144V was detected in FMDVs O-VN-CTU-VL1 (PP897837) and FMDV O-VN-CTU-TV1 (PP897840). No recombinant events were detected at VP1 sequences. In brief, genetic analysis of VP1 nucleotide and amino acid sequences of isolated FMDVs contributed to detecting the mutation which was able to cause the emergence of new strains as well as to elucidate the evolution of FMDVs circulating in the Mekong Delta Provinces.

Foot-and-mouth disease: genomic and proteomic structure, antigenic sites, serotype relationships, immune evasion, recent vaccine development strategies, and future perspectives

Foot-and-mouth disease (FMD) is a highly contagious and transmissible disease that can have significant economic and trade repercussions during outbreaks. In Egypt, despite efforts to mitigate FMD through mandatory immunization, the disease continues to pose a threat due to the high genetic variability and quasi-species nature of the FMD virus (FMDV). Vaccines have been crucial in preventing and managing FMD, and ongoing research focusses on developing next-generation vaccines that could provide universal protection against all FMDV serotypes. This review thoroughly examines the genetic structure of FMDV, including its polyprotein cleavage process and the roles of its structural and non-structural proteins in immune evasion. Additionally, it explores topics such as antigenic sites, specific mutations, and serotype relationships from Egypt and Ethiopia, as well as the structural changes in FMDV serotypes for vaccine development. The review also addresses the challenges associated with creating effective vaccines for controlling FMD, particularly focusing on the epitope-based vaccine. Overall, this review offers valuable insights for researchers seeking to develop effective strategies and vaccines for controlling FMD.

Emergence of new sublineages of serotype O foot-and-mouth disease viruses circulating in Pakistan during 2012-2021

Foot-and-mouth disease (FMD) is endemic in Pakistan and serotypes O, A and Asia-1 of FMD virus (FMDV) are responsible for the outbreaks in the country. The dominant serotype is type O represented by the O/ME-SA/PanAsia-2 lineage, which has diverged into different sublineages. Characterizing circulating viruses helps to trace the origin of outbreaks and provides evidence to select appropriate vaccines. The present study characterized viruses belonging to the O/ME-SA/PanAsia-2 lineage collected from bovines during 2012-2021. Phylogenetic analyses using the VP1 coding sequences revealed that these viruses grouped into five sublineages, of which two have been described previously, i.e. O/ME-SA/PanAsia-2BAL-09 and O/ME-SA/PanAsia-2ANT-10, while the three new sublineages are designated here as O/ME-SA/PanAsia-2KHO-10, O/ME-SA/PanAsia-2ICT-12 and O/ME-SA/PanAsia-2PUN-16. Antigenic profiling of selected viruses belonging to the PanAsia-2ICT-12 and PanAsia-2PUN-16 sublineages was carried out using antisera raised against three reference vaccine strains: O Manisa, O/TUR 5/2009 and O 3039. The data highlighted that some of the viruses, belonging to these sublineages, were not efficiently neutralized by the reference antisera. This may be due to the individual or combined effects of multiple amino acid changes in these field isolates at known antigenic sites. This study reveals that serotype O FMDVs are continuously evolving in Pakistan and that continuous surveillance to characterize viruses causing field outbreaks is important to identify the emergence of new FMDV sublineages that may be poorly controlled using existing FMD vaccines.

Detection and genomic characterization of foot and mouth disease virus SAT2 XIV topotype using amplicon-based nanopore sequencing

Foot and mouth disease (FMD) is a highly contagious vesicular viral disease that infects cloven-hoofed animals. This disease is caused by Foot-and-mouth disease virus (FMDV) which is composed of seven serotypes (O, A, C, Asia-1, SAT1, SAT2, and SAT3), each of which lacks cross immune protection among serotypes which complicates vaccination strategies. For that, sequencing of viral protein 1 (VP1) is crucial to identify circulating serotypes in a country. Jordan is endemic for FMD, with primarily O and A serotypes circulating according to previous data. However, the epidemiological status of FMD requires updates in Jordan. In this study, out of 200 samples collected during a recent outbreak in Al-Dhlail, Jordan in early 2023, forty-nine were positive by quantitative polymerase chain reaction (qPCR). Fourteen of these positive samples were selected for PCR amplification of the viral protein 1 (VP1) gene, which were then sequenced using nanopore technology. Phylogenetic analysis highlighted the presence of SAT2 XIV topotype, with eleven samples successfully sequenced using this approach. In addition to that, Sanger sequencing validated a N137S SNP in the VP1 protein that initially identified by our approach. This study provides additional data that can be used and incorporated into the national and global efforts against this disease with new means of diagnostics methods.

Spatial-temporal distribution and risk factors of foot and mouth disease outbreaks in Java Island, Indonesia from 2022 to 2023

BACKGROUND

Indonesia faced new outbreaks of foot and mouth disease in 2022 after being officially free from the disease for several decades. The outbreaks were first reported in East Java in April 2022 and subsequently spread to many regions in Indonesia. This study investigated the epidemiology and risk factors of foot and mouth disease outbreaks in Java, Indonesia, from 2022 to 2023. Descriptive, spatial, spatiotemporal, and risk factor analyses were conducted to investigate the patterns and risk factors associated with the outbreaks in Java.

RESULTS

Results showed that the outbreaks were distributed across the island. East Java was the most affected region. The outbreaks peaked in June 2022, followed by a downward trend until 2023. Positive spatial autocorrelations were found in both years, indicating that the outbreaks clustered in several areas. The spatiotemporal analysis found a total of 16 clusters in both years, with 11 clusters in 2022 and 5 clusters in 2023. The temporal distribution of clusters indicated a peak period from May to July, with 12 out of 16 clusters occurring during this time. Risk factor analysis found that environmental and agricultural-related factors, including annual precipitation, the presence of livestock markets, the presence of slaughterhouses, the presence of animal health centres, cattle population, and goat population, are significant risk factors for the occurrence of outbreaks in Java. Probability risk mapping found higher risk areas primarily distributed in the eastern and central parts of Java.

CONCLUSIONS

The outbreaks predominantly clustered in eastern and central parts of Java. The outbreaks peaked in June 2022, followed by a downward trend until the end of 2023. Environmental and agricultural-related factors significantly increased the risk of outbreak occurrence.

Validation of two multiplex lateral flow devices for the rapid detection and typing of foot-and-mouth disease viruses

Lateral Flow Devices (LFDs) represent a simple tool for the rapid diagnosis of FMD, particularly in endemic regions, often lacking adequate and equipped laboratories. Other experimental prototypes offer a user-friendly FMD confirmation tool, but serotype identification is crucial for transmission patterns evaluation and for vaccine selection and their serotyping capacity was limited. This study describes the validation of two multiplex devices based on well-characterized monoclonal antibodies: LFD1 (O, A and Asia1) and LFD2 (SAT1 and SAT2). First, the ability of the LFDs to recognize the widest spectrum of strains was assessed. Eighty-three tissue-cultured FMDV strains were tested with LFD1 and 15 with LFD2, confirming the capability to recognize and serotype a broad range of lineages and sub-lineages belonging to all 7 endemic pools. The diagnostic sensitivity related to FMDV detection was evaluated using 224 real-time RT-PCR positive samples collected in endemic countries, resulting in 87.5 % for LFD1 (140/160 detected) and 70 % for LFD2 (45/64 detected). The diagnostic sensitivity of serotyping capabilities was assessed by testing field samples in parallel with an antigen-ELISA kit: applied on 178 samples, LFD1 correctly typed 96 %, 94 % and 83 % of samples positive for type O (n = 95), A (n = 54) and Asia1 (n = 29) respectively, while LFD2 correctly typed 77 % SAT1 (n = 52) and 82 % SAT2 (n = 40) in 92 positive field samples. A 100 % diagnostic specificity was found testing 60 epithelium homogenates collected from animals negative for FMD. Obtained data highlighted the devices' potential value for field use to support the enhanced surveillance of FMD.

New BODIPY-Labeled Antibody for Detection of Foot-and-Mouth Disease Virus

Detecting complete viral particles in vaccines is essential for both monitoring vaccine production and ensuring vaccine quality. Currently, sucrose density gradient centrifugation is the standard method for measuring the antigen content in conventional inactivated vaccines, but it requires specialized equipment and skilled personnel. Recently, BODIPY (BDP) dyes have gained attention in biomolecular studies due to their modifiable parent structure, although their use in macromolecular proteins remains limited. This study successfully synthesized a fluorescent antibody, BDP-VHH (variable domain of a heavy chain of a heavy chain-only antibody), through the nucleophilic substitution of BDP-2Cl with VHH, which recognizes the 146S antigen of the foot-and-mouth disease virus (FMDV). We investigated its use in quantifying FMDV serotype O antigen and cell imaging. The results showed that the BDP-VHH-based method can quantify the antigen within 1 h with good repeatability and sensitivity. Compared with FITC-conjugated antibodies, BDP-VHH demonstrated improved light stability. This study provides a foundation for the use of BDP fluorescent dyes in the macromolecular biological research.

Emergency response for recently isolated Foot and Mouth Disease virus type A Africa in Egypt 2022

Foot and mouth disease (FMD) is a highly contagious viral infection affecting cloven-hoofed ruminants, leading to significant economic losses. In 2022, Egypt faced a severe outbreak of Foot and Mouth Disease (FMD) caused by the A/Africa/G-IV variant. This study assessed the efficacy of local and imported FMDV vaccines (A Iran-05 lineage) against this new variant using in vitro and in vivo methods. Sera from vaccinated calves showed inadequate cross-protection, with mean r1-values of 0.235 and 0.243 for local and imported vaccines, respectively. Challenge tests indicated low protection levels (20% and 40%) against A/Africa/G-IV compared with A/Iran/05. Current vaccines were deemed ineffective, prompting a formulation update incorporating the variant. The modified vaccine is now deployed in proactive vaccination efforts to address the evolving FMD outbreak.

Preparation and application of porcine broadly neutralizing monoclonal antibodies in an immunoassay for efficiently detecting neutralizing antibodies against foot-and-mouth disease virus serotype O

Neutralizing antibodies provide vital protection against foot-and-mouth disease virus (FMDV). The virus neutralization test (VNT) is a gold standard method for the detection of neutralizing antibodies. However, its application is limited due to the requirement for live virus and unsuitability for large-scale serological surveillance. In this study, a porcine broadly neutralizing monoclonal antibody (PO18-10) against FMDV was obtained from the heterologous sequentially vaccinated pig using single-B-cell antibody technology. A competitive enzyme-linked immunosorbent assay (C-ELISA) for detecting neutralizing antibodies against FMDV serotype O was developed using biotinylated PO18-10 as a detector antibody. The sensitivity and specificity of the assay were 100% and 99.55%, respectively, and the positive/negative coincidence rate with VNT was 94%, suggesting that C-ELISA based on natural host-derived monoclonal antibody (mAb) could be a promising tool to detect neutralizing antibodies against FMDV serotype O and evaluate the vaccine efficacy.IMPORTANCEFoot-and-mouth disease virus (FMDV) serotype O is one of the most prevalent serotypes in the world. The neutralizing antibody titers in primo-vaccinated animals are directly related to their level of protection against a virus challenge. The development of a safe, rapid, and accurate method for the detection of the neutralizing antibody is essential for the control and eradication of FMD. In this study, an inter-serotype broadly neutralizing monoclonal antibody PO18-10 was successfully produced using single-B-cell antibody technology from sequentially vaccinated pigs. A competitive ELISA based on this natural host-derived mAb for the detection of neutralizing antibodies against FMDV serotype O was developed and validated. The assay demonstrates high sensitivity, specificity, and coincidence rate with VNT, making it an alternative tool for confirming FMDV infection and evaluating the vaccine efficacy.

Risk Assessment and Prevention of Foot-and-Mouth Disease Transmission from Laos to China

Foot-and-mouth disease (FMD) is classified as a Class I animal disease in China and listed as one of the notifiable animal diseases by the World Organization for Animal Health (WOAH). It significantly impacts the safe production of livestock and the trade of animals and related products. China's Yunnan Province shares a 710 km border with Laos, with frequent cross-border trade, and the cross-border flow of animals and related products occurs from time to time. In order to prevent the introduction of FMD from the border areas of Laos into China, this study conducted an assessment of the entry, exposure, and consequences of FMD transmission. The findings revealed a "high" risk in terms of entry assessment, a "medium" risk in exposure assessment, and a "high" risk in the consequence assessment. Based on these assessments, the overall risk level for the introduction of FMD from Laos into China is determined to be "high". Therefore, it is recommended that management measures are implemented, such as restricting animal movement across borders and strengthening inspection procedures for animals entering China, to effectively prevent FMD introduction from Laos.

Sensitivity of specimen type for diagnosing foot-and-mouth diseases in cattle using one-step real-time polymerase chain reaction (3D gene)

Background

Indonesia is currently experiencing a foot-and-mouth disease (FMD) outbreak in livestock, caused by the FMD virus (FMDV). FMDV is easily spread to cause outbreaks in new geographical locations. Identifying FMDV infection through early diagnostic testing is important to track and prevent the spread of FMD in Indonesia. The use of appropriate samples is a crucial step in a study or survey to provide accurate results for diagnosis.

Aim

The aim of our study was to evaluate the sensitivity of relevant oral mucosal epithelial swabs, hypersalivation swabs, and blood plasma specimen samples for FMDV diagnosis using one-step real time PCR (3D).

Methods

Sampling was carried out by judgment or purposive, namely selecting animals that showed symptoms of the disease. A total of 109 samples were collected consisting of 3 types of oral mucosal epithelial swab specimens, hypersalivation swabs, and blood plasma collected from each cow reported as suspected FMDs in 8 districts in South Sulawesi were tested for FMDV using one-step RT-PCR (3D).

Results

FMDV infection in oral mucosal epithelial swabs (ct = 28.9), saliva (ct = 30.62), and blood plasma (ct = 37.17) compared to controls used from the Farma Veterinary Center (ct = 29.10) using RT PCR (3D gene). These results indicate that the sensitivity value of oral mucosal epithelial swab specimens is the same as positive controls, even more sensitive, than when compared to saliva or blood plasma specimens. Sensitivity depends on the cycle threshold (CT) value for each RT PCR test and should be preferred in crucial situations if possible.

Conclusion

These findings indicate that using oral mucosal epithelial swab specimens is more sensitive to be used as superior samples for FMDV detection using RT-PCR (3D) as a powerful tool for early detection to enable faster and effective treatment.

Sensitivity of specimen type for diagnosing foot-and-mouth diseases in cattle using one-step real-time polymerase chain reaction (3D gene)

Background

Indonesia is currently experiencing a foot-and-mouth disease (FMD) outbreak in livestock, caused by the FMD virus (FMDV). FMDV is easily spread to cause outbreaks in new geographical locations. Identifying FMDV infection through early diagnostic testing is important to track and prevent the spread of FMD in Indonesia. The use of appropriate samples is a crucial step in a study or survey to provide accurate results for diagnosis.

Aim

The aim of our study was to evaluate the sensitivity of relevant oral mucosal epithelial swabs, hypersalivation swabs, and blood plasma specimen samples for FMDV diagnosis using one-step real time PCR (3D).

Methods

Sampling was carried out by judgment or purposive, namely selecting animals that showed symptoms of the disease. A total of 109 samples were collected consisting of 3 types of oral mucosal epithelial swab specimens, hypersalivation swabs, and blood plasma collected from each cow reported as suspected FMDs in 8 districts in South Sulawesi were tested for FMDV using one-step RT-PCR (3D).

Results

FMDV infection in oral mucosal epithelial swabs (ct = 28.9), saliva (ct = 30.62), and blood plasma (ct = 37.17) compared to controls used from the Farma Veterinary Center (ct = 29.10) using RT PCR (3D gene). These results indicate that the sensitivity value of oral mucosal epithelial swab specimens is the same as positive controls, even more sensitive, than when compared to saliva or blood plasma specimens. Sensitivity depends on the cycle threshold (CT) value for each RT PCR test and should be preferred in crucial situations if possible.

Conclusion

These findings indicate that using oral mucosal epithelial swab specimens is more sensitive to be used as superior samples for FMDV detection using RT-PCR (3D) as a powerful tool for early detection to enable faster and effective treatment.

Enhanced Immunogenicity of Foot-and-Mouth Disease Virus-like Particles Using a Water-in-Oil-in-Water Adjuvant

BACKGROUND

Foot-and-mouth disease (FMD) causes significant economic losses, prompting vaccination as a primary control strategy. Virus-like particles (VLPs) have emerged as promising candidates for FMD vaccines but require adjuvants to enhance their immunogenicity. In this study, we evaluated the immunogenicity of a VLP-based vaccine with a water-in-oil-in-water (W/O/W) emulsion adjuvant, named WT.

METHODS

The WT adjuvant was mixed with FMD VLPs to form the VLPs+WT vaccine. The size and stability of the vaccine were analyzed. BALB/c mice were immunized with the VLPs+WT vaccine, and immunological responses were assessed through antibody measurements, cytokine profiling, and gene expression analysis. In addition, splenic lymphocyte proliferation and signaling pathways were examined.

RESULTS

The VLPs+WT vaccine exhibited a homogeneous size of 324.60 ± 2.30 nm and a viscosity of 8.76 mPa·s, indicating good stability. Immunized mice showed steady weight gain and no organ abnormalities. Compared to the VLPs group, the VLPs+WT group induced significantly higher levels of specific antibodies that persisted for 12 weeks, similar to the commercial VLPs+ISA201 vaccine. The VLPs+WT vaccine also enhanced the secretion of Th1-related (IgG2a, IFN-γ) and Th2-related (IgG1, IL-4) molecules. WT stimulated splenic lymphocyte proliferation and differentiation, primarily activating B-cell receptor signaling and phagosome pathways. It also upregulated genes associated with MHC and interferon stimulation while promoting the expression of MyD88, PI3K, AKT, p65, and p-p65 proteins.

CONCLUSIONS

These findings suggest that WT is an effective adjuvant for FMD VLP-based vaccines, with potential for improving vaccine efficacy.

A Review of the Utility of Established Cell Lines for Isolation and Propagation of the Southern African Territories Serotypes of Foot-and-Mouth Disease Virus

Cell culture underpins virus isolation and virus neutralisation tests, which are both gold-standard diagnostic methods for foot-and-mouth disease (FMD). Cell culture is also crucial for the propagation of inactivated foot-and-mouth disease virus (FMDV) vaccines. Both primary cells and cell lines are utilised in FMDV isolation and propagation. Widely used cell lines for FMDV and isolation and propagation include baby hamster kidney cells (BHK-21), swine kidney cells (IB-RS-2), foetal goat tongue (ZZ-R 127), foetal porcine kidney cells (LFBKvB6), bovine kidney cells (BK), human telomerase reverse transcriptase bovine thyroid (hTERT-BTY) and porcine kidney-originating PK-15 or SK 6 cell lines. This review highlights how different receptors and molecules-integrins, heparan sulphate (HS), and the Jumonji C-domain containing Protein 6 (JMJD6)-found on the surface of different cell types contribute to differences experienced with susceptibility and sensitivity of the cells to infection with different serotypes of FMDV. This review specifically focuses on Southern African territory (SAT) serotypes, which are unique to the Southern African context and are often under-investigated in cell line development for FMDV isolation and propagation.

The Presence of Two Distinct Lineages of the Foot-And-Mouth Disease Virus Type A in Russia in 2013-2014 Has Significant Implications for the Epidemiology of the Virus in the Region

Molecular surveillance of FMD epidemiology is a fundamental tool for advancing our understanding of virus biology, monitoring virus evolution, and guiding vaccine design. The accessibility of genetic data will facilitate a more comprehensive delineation of FMDV phylogeny on a global scale. In this study, we investigated the FMDV strains circulating in Russia during the 2013-2014 period in geographically distant regions utilizing whole genome sequencing followed by maximum-likelihood phylogenetic reconstruction of whole genome and VP1 gene sequences. Phylogenetic analysis showed congruence in the topology of the phylogenetic trees constructed using the complete genome and VP1 gene sequence, clearly demonstrating that the isolates analyzed belong to two distinct genetic lineages: A/SEA97 in the Far East and Iran-05 in the North Caucasus. The A/SEA97 isolates exhibited a close genetic identity to those from China and Mongolia, whereas the Iran-05 isolates demonstrated clusterization with those from Turkey. The vaccine-matching studies with isolates from the Far East and North Caucasus revealed no antigenic homology with A/SEA-97 (r1 = 0.015-0.29) and A/Iran 05 (r1 = 0.009-0.17). The close genetic relationship of FMDV in the reported outbreak waves to those from neighboring countries indicates that animal movement could contribute to spillover and virus dispersal. The phylogenetic data reported here provide insight into the molecular epidemiology of FMD in the Eurasia region, elucidating the circulation pattern, molecular evolution, and genetic diversity, which is highly valuable for guiding vaccine designs and improving regional eradication policies.

Next-generation adjuvant systems containing furfurman drives potent adaptive immunity and host defense as a foot-and-mouth disease vaccine adjuvant

Introduction

Many countries use commercial foot-and-mouth disease (FMD) vaccines to prevent FMD pandemics, but these vaccines have disadvantages, such as repeated vaccinations due to the short persistence of antibody (Ab) titers and incomplete host defense despite high Ab titers. To address these shortcomings, we aimed to develop a novel FMD vaccine containing furfurman as an adjuvant.

Method

To demonstrate the efficacy of the test vaccine, adaptive immunity was evaluated by measuring Ab and neutralizing Ab titers and host defense against viral infections in experimental and target animals. In addition, the expression levels of cytokines [interferon (IFN)α, IFNβ, IFNγ, interleukin (IL)-1β, IL-2, and IL-12p40] were evaluated at the early stages of vaccination to confirm the simultaneous induction of cellular and humoral immune responses induced by the test vaccine.

Result

The groups that received vaccine containing furfurman showed a strong early, mid-term, and long-term immune response and host defense against viral infections compared to the control groups. The significant upregulation observed in cytokine levels in the furfurman group compared to those in the control groups strongly suggest that the test vaccine strengthens cellular immune response and effectively induces a humoral immune response.

Conclusion

Our study demonstrated that furfurman, as an FMD vaccine adjuvant, achieves long-lasting immunity and host defense against viral infections by eliciting potent cellular and humoral immune responses. Therefore, our findings contribute to the design of next-generation FMD vaccines and highlight the potential application of furfurman as an adjuvant for other viral diseases.

Chemical and Heat Treatment for Viral Inactivation in Porcine-Derived Gelatin

BACKGROUND

It is mandatory to demonstrate the removal or inactivation of potential viral contaminants in the manufacturing processes of pharmaceuticals derived from biomaterials. Porcine-derived gelatin is used in various medical fields, including regenerative medicine, tissue engineering, and medical devices. However, the steps of virus inactivation in the gelatin manufacturing process are poorly defined. In this study we evaluated virus inactivation in two steps of the gelatin manufacturing process.

METHODS

Pig skin (4.5 g), including solid pieces as intermediate products, was spiked with model viruses, including CPV (canine parvovirus), BAV (bovine adenovirus), BPIV3 (bovine parainfluenza type 3), PRV (pseudorabies virus), BReoV3 (bovine reovirus type 3), and PPV (porcine parvovirus), and underwent chemical treatment with alkaline ethanol or heat treatment at 62 °C followed by inoculation in relevant cell cultures. Viral titers in the samples were calculated based on the Behrens-Kärber method.

RESULTS

Model viruses were inactivated at different rates; however, effective inactivation of all model viruses was demonstrated by an LRV (log reduction value) over 4 by both chemical and heat treatment, and chemical treatment demonstrated rapid inactivation compared to heat treatment.

CONCLUSION

The chemical and heat treatment steps exhibited meaningful viral inactivation capacity. They are integrated parts in the extraction and manufacturing process of porcine-derived gelatin, ensuring virus safety for use in medical applications.

Evaluation of commercial quadrivalent foot-and-mouth disease vaccines against east African virus strains reveals limited immunogenicity and duration of protection

Foot-and-mouth disease virus (FMDV) causes a contagious disease (FMD) in cloven-hoofed animals. For FMD-endemic countries, vaccination is critical for controlling disease but is rarely monitored, despite substantial funds spent on vaccine purchases. We evaluated antibody responses in cattle to two commercial vaccines each containing antigens of four FMDV serotypes. Sampling was done over 360 days, with serology for each serotype performed using commercially available solid phase competition ELISAs (SPCE) and with virus neutralization tests (VNT) employing regionally relevant test viruses. A primary course of each vaccine was administered to 37 calves, some of which received a second dose after 28 days. Using new production batches of vaccines, all calves received a booster vaccination 180 days post vaccination, while 10 additional naïve calves were also vaccinated using the new batches and followed up for ∼180 days. Simple and general linear models were used to compare antibody responses which varied substantially according to vaccine, dose regime, serotype, and test, but were mostly insufficient to ensure a high likelihood of adequate or sustained probable protection. One of the vaccines administered as a two-dose primary course of vaccination was superior to other options, but even then, data trajectories from VNT responses suggested probable protection of 75 % of calves for 6 months for only one virus serotype. Calves administered with the other vaccine and those given a single primary dose developed low levels of antibodies, offering predicted likely protection lasting less than two months. Individual SPCE results were weakly correlated (r2 = 0.48) to neutralization and associated likelihoods of protection but SPCE and VNT agreed on which vaccine and dose regime performed best. Our findings highlight gaps in immunogenicity of FMD vaccines used in East Africa and reinforce the importance of independent quality control studies to evaluate and improve commercial FMD vaccines and vaccination regimes.

Expression of virus-like particles (VLPs) of foot-and-mouth disease virus (FMDV) using Saccharomyces cerevisiae

We engineered Saccharomyces cerevisiae to express structural proteins of foot-and-mouth disease virus (FMDV) and produce virus-like particles (VLPs). The gene, which encodes four structural capsid proteins (VP0 (VP4 and VP2), VP3, and VP1), followed by a translational "ribosomal skipping" sequence consisting of 2A and protease 3C, was codon-optimized and chemically synthesized. The cloned gene was used to transform S. cerevisiae 2805 strain. Western blot analysis revealed that the polyprotein consisting of VP0, VP3, and VP1 was processed into the discrete capsid proteins. Western blot analysis of 3C confirmed the presence of discrete 3C protein, suggesting that the 2A sequence functioned as a "ribosomal skipping" signal in the yeast for an internal re-initiation of 3C translation from a monocistronic transcript, thereby indicating polyprotein processing by the discrete 3C protease. Moreover, a band corresponding to only VP2, which was known to be non-enzymatically processed from VP0 to both VP4 and VP2 during viral assembly, further validated the assembly of processed capsid proteins into VLPs. Electron microscopy showed the presence of the characteristic icosahedral VLPs. Our results clearly demonstrate that S. cerevisiae processes the viral structural polyprotein using a viral 3C protease and the resulting viral capsid subunits are assembled into virion particles. KEY POINTS: • Ribosomal skipping by self-cleaving FMDV peptide in S. cerevisiae. • Proteolytic processing of a structural polyprotein from a monocistronic transcript. • Assembly of the processed viral capsid proteins into a virus-like particle.

Oral Administration of Zinc Sulfate with Intramuscular Foot-and-Mouth Disease Vaccine Enhances Mucosal and Systemic Immunity

Background/Objectives: Foot-and-mouth disease (FMD) remains a significant global threat to livestock farming. Current commercial FMD vaccines present several challenges, including the risk of infection and adverse injection site reactions due to oil-based adjuvants. The complex immune environment of the gut-associated lymphoid tissue has the potential to induce broad and diverse immune responses. Therefore, we aimed to explore the potential of zinc sulfate as an oral adjuvant to enhance intestinal mucosal immunity and complement the effects of intramuscular (IM) FMD vaccination. Methods: We conducted serological analyses on mice and pigs, measuring secretory IgA (sIgA) levels and evaluating the expression of mucosal immunity-related genes in pigs. These assessments were used to investigate the systemic and mucosal immune responses induced by oral zinc sulfate administration in combination with an IM FMD vaccine. Results: This combination strategy significantly increased structural protein antibody titers and virus neutralization titers in experimental animals (mice) and target animals (pigs) across early, mid-, and long-term periods. Additionally, this approach enhanced the expression of key cytokines associated with mucosal immunity and increased sIgA levels, which are critical markers of mucosal immunity. Conclusions: Oral zinc sulfate administration may synergize with inactivated FMD vaccines, leading to sustained and enhanced long-term immune responses. This novel strategy could reduce the frequency of required vaccinations or allow for a lower antigen dose in vaccines, effectively stimulating the mucosal immune system and boosting systemic immunity. This approach has the potential to improve the overall efficacy of commercial FMD vaccines.

Dendritic cell-based biomimetic nanoparticles for foot-and-mouth disease induce robust cellular immunity

Foot-and-mouth disease (FMD) is a highly contagious and economically devastating viral disease of ruminants and swine, badly affecting the livestock industry worldwide. In clinical practice, vaccination is a frequently employed strategy to prevent foot-and-mouth disease (FMDV). However, commercial inactivated vaccines for FMD mainly rely on humoral immunity, exhibiting poor cellular immune responses and causing adverse reactions. Here, we use the double emulsion method to prepare poly (lactic-co-glycolic acid) nanoparticles (PLGA-NP) encapsulated with IL-2 cytokines, wrap the dendritic cell (DC) membrane carrying FMDV antigen information on the surface of the nanoparticles, obtaining a biomimetic nanoparticle vaccine Biom@DC with uniform size. This vaccine can effortlessly move through lymph nodes due to its nanoscale size advantage. It also possesses DC ability to present antigens, and antigen presentation can be made more effective with high biocompatibility. The sustained release of IL-2 encapsulated in the core of PLGA-NP in vivo can effectively promote the body's cellular immune response. Immune tests on mice have shown that Biom@DC may greatly increase T cell activation and proliferation both in vivo and in vitro, while also significantly reducing the fraction of inhibitory Treg cells. Furthermore, in the micro serum neutralization assay for FMDV, it has been demonstrated that the group vaccinated with Biom@DC exhibits a clear neutralizing effect. Given its strong immunogenicity, Biom@DC has the potential to develop into a novel, potent anti-FMDV vaccination.

An evaluation of the efficiency and effectiveness of diagnostic tests for foot and mouth disease: are novel diagnostic tests for FMD more feasible than conventional tests in Southeast Asia?

Foot and mouth disease (FMD) remains endemic in many areas of continental Southeast Asia (SEA). It is responsible for substantial economic losses in the smallholder sector and threatens livelihoods. In recent years, novel diagnostic tests have been developed which reportedly detect FMD virus more effectively and efficiently. This critically appraised topic (CAT) aimed to evaluate the feasibility of these diagnostic tests for FMD in SEA compared to conventional tests. Relevant studies that evaluate diagnostic tests are identified and critically assessed, and recommendations are made on suitable potential diagnostic tests for use in the smallholder sector in SEA. A systematic search of electronic databases (CABI: CAB Abstracts, Web of Science Core Collections) was carried out to identify relevant studies that compared novel and conventional diagnostic tests. The search strategy initially identified 12 papers, of which six fulfilled all the inclusion criteria and were selected for this review. Most of the selected studies had limitations in design and comparability, making it difficult to validly compare the effectiveness and efficiency of the relevant diagnostic tests. These limitations include variation in sample characteristics, methodology, measurable outcomes and the different aspects of the diagnostic tests that each study focused on. Most studies concluded that novel diagnostic tests were more effective and efficient than conventional tests: had greater analytical sensitivity and specificity, were more robust, had a wider range of processable sample types and serotypes, could detect various diseases, had faster testing speeds and provided greater value for money. However, strong recommendations on which specific diagnostic test to rely on could not be made, since there was conflicting evidence and multiple confounding factors. Overall, the evidence found did not entirely apply to the target scenario, being SEA smallholder farms. Recommendations for the target scenario were also made based on the study findings.

Analysis of the immunological response elicited by a polyvalent foot and mouth disease vaccine and its compatibility with a diva test in Jimma Town, Ethiopia

The research was conducted in Jimma town, Oromiya Regional State, from October 2022 to June 2023, with the aim of assessing the immune response of polyvalent FMD (Foot and Mouth Disease) vaccine. The study involved 34 cattle in a longitudinal study, divided into two groups: 29 vaccinated and 5 unvaccinated. The vaccinated cattle received an inactivated polyvalent FMD virus vaccine produced by the National Veterinary Institute. Blood samples were collected on days 0, 14, 21, 35, 80, and 125 after vaccination and tested using Virus Neutralization Test and 3ABC ELISA. The results showed a significant increase in neutralizing antibodies against structural proteins in all vaccinated cattle on day 14 after vaccination for all three serotypes. (A/ETH/21/2000, p = 0.015; O/ETH/38/2005, p = 0.017; SAT2/ETH/64/2009, p = 0.007). On day, fourteen of post-vaccination vaccinated group showed immune response equal or above 1.5 log10 in a proportion of 69%, 73% and 94% for serotype A/ETH/21/2000, O/ETH/38/2005 and SAT2/ETH/64/2009 respectively. The status of raised antibody titer on day 125 post-vaccination showed decreasing by 14%, 18% and 4% for serotype A/ETH/21/2000, O/ETH/38/2005 and SAT2/ETH/64/2009 respectively. The DIVA test, or 3ABC ELISA, used to differentiate infected from vaccinated animals, revealed the absence of immune response to the Non-structural protein in the vaccinated cattle group. Conversely, the unvaccinated group showed no recorded antibody titer to both structural and non-structural proteins. In summary, the commercially available FMD vaccine, comprising serotype A, O, and SAT2, triggers an immune response to the structural protein rather than the non-structural protein after the initial administration. This outcome implies that FMD vaccines from the National Veterinary Institute align with the DIVA test. Nevertheless, additional efforts may be necessary to bolster the strength and duration of the vaccine-induced immune response.

Dual effects of ipecac alkaloids with potent antiviral activity against foot-and-mouth disease virus as replicase inhibitors and direct virucides

Foot-and-Mouth Disease (FMD) is a contagious, blistering disease caused by the Foot-and-Mouth Disease virus (FMDV), which affects livestock globally. Currently, no commercial antiviral agent is available for effective disease control. This study investigated the antiviral potential of natural-derived alkaloids against FMDV in BHK-21 cells. Twelve alkaloids were assessed for their antiviral activities at various stages of FMDV infection, including pre-viral entry, post-viral entry, and prophylactic assays, as well as attachment and penetration assays by evaluating cytopathic effect reduction and directed-virucidal effects. The results showed that ipecac alkaloids, cephaeline (CPL) and emetine (EMT), exhibited dual effects with robust antiviral efficacy by reducing cytopathic effect and inhibiting FMDV replication in a dose-dependent manner. Evaluation through immunoperoxidase monolayer assay and RT-PCR indicated effectiveness at post-viral entry stage, with sub-micromolar EC50 values for CPL and EMT at 0.05 and 0.24 µM, respectively, and high selective indices. Prophylactic effects prevented infection with EC50 values of 0.23 and 0.64 µM, respectively. Directed-virucidal effects demonstrated significant reduction of extracellular FMDV, with CPL exhibiting a dose-dependent effect. Furthermore, the replicase (3Dpol) inhibition activity was identified using the FMDV minigenome assay, which revealed strong inhibition with IC50 values of 0.15 µM for CPL and 4.20 µM for EMT, consistent with the decreased negative-stranded RNA production. Molecular docking confirmed the interaction of CPL and EMT with residues in the active site of FMDV 3Dpol. In conclusion, CPL and EMT exhibited promising efficacy through their dual effects and provide an alternative approach for controlling FMD in livestock.

Use of virus-like particles and nanoparticle-based vaccines for combating picornavirus infections

Picornaviridae are non-enveloped ssRNA viruses that cause diseases such as poliomyelitis, hand-foot-and-mouth disease (HFMD), hepatitis A, encephalitis, myocarditis, and foot-and-mouth disease (FMD). Virus-like particles (VLPs) vaccines mainly comprise particles formed through the self-assembly of viral capsid proteins (for enveloped viruses, envelope proteins are also an option). They do not contain the viral genome. On the other hand, the nanoparticles vaccine (NPs) is mainly composed of self-assembling biological proteins or nanomaterials, with viral antigens displayed on the surface. The presentation of viral antigens on these particles in a repetitive array can elicit a strong immune response in animals. VLPs and NPs can be powerful platforms for multivalent antigen presentation. This review summarises the development of virus-like particle vaccines (VLPs) and nanoparticle vaccines (NPs) against picornaviruses. By detailing the progress made in the fight against various picornaviruses such as poliovirus (PV), foot-and-mouth disease virus (FMDV), enterovirus (EV), Senecavirus A (SVA), and encephalomyocarditis virus (EMCV), we in turn highlight the significant strides made in vaccine technology. These advancements include diverse construction methods, expression systems, elicited immune responses, and the use of various adjuvants. We see promising prospects for the continued development and optimisation of VLPs and NPs vaccines. Future research should focus on enhancing these vaccines' immunogenicity, stability, and delivery methods. Moreover, expanding our understanding of the interplay between these vaccines and the immune system will be crucial. We hope these insights will inspire and guide fellow researchers in the ongoing quest to combat picornavirus infections more effectively.

Development and Validation of Serotype-Specific Blocking ELISA for the Detection of Anti-FMDV O/A/Asia1/SAT2 Antibodies

Foot-and-mouth disease (FMD) is one of the most infectious viral transboundary diseases of livestock, which causes devastating global economic losses. Different enzyme-linked immunosorbent assays (ELISAs) are used for sero-surveillance of the foot-and-mouth disease virus (FMDV). However, more sensitive, accurate, and convenient ELISAs are still required to detect antibodies against FMDV serotypes. The primary goal of this study was to establish serotype-specific monoclonal antibody (mAb)-based blocking ELISAs (mAb-bELISAs) that would provide better performance characteristics or be equivalent in performance characteristics compared with a conventional polyclonal antibody (pAb)-based competitive ELISA (pAb-cELISA). Four mAb-bELISAs were developed using FMDV serotype-specific mAbs for the detection of anti-FMDV/O/A/Asia1/SAT2 antibodies. Using a 50% cut-off, all four mAb-bELISAs exhibited species-independent 99.74%, 98.01%, 96.59%, and 98.55% diagnostic specificity (DSp) and 98.93%, 98.25%, 100%, and 87.50% diagnostic sensitivity (DSe) for FMDV serotypes O, A, Asia1, and SAT2, respectively. In addition, a 100% DSe of serotypes O- and SAT2-specific mAb-bELISAs was observed for porcine sera when the cut-off was 30%. All mAb-bELISAs developed in this study displayed high repeatability/reproducibility without cross-reactivity. Finally, the diagnostic performance of mAb-bELISAs was found to be better than or equivalent to compared with pAb-cELISAs, suggesting that mAb-bELISAs can be used to replace existing pAb-ELISAs for the detection of antibodies against these four FMDV serotypes.

Oral immunization against foot-and-mouth disease virus using recombinant Saccharomyces cerevisiae with the improved expression of the codon-optimized VP1 fusion protein

VP1, a major immunogenic protein of foot-and-mouth disease virus (FMDV), facilitates viral attachment and entry into host cells. VP1 possesses critical epitope sequences responsible for inducing neutralizing antibodies but its expression using Saccharomyces cerevisiae has been hampered despite evidence that the presence of VP1 does not negatively impact the yeast's biology. In this study, we fused proteins to enhance VP1 expression using S. cerevisiae. Among short P1 chimeras containing VP1 including VP3-VP1 and VP2-VP1, VP3-VP1 fusion proteins showed higher expression levels than VP2-VP1. We subsequently designed new fusion proteins, of which 20 amino acids of N-terminal VP3 fused with VP1-Co1 (referred to 20aaVP3-VP1-Co1) showed the highest expression level. Lowering the culture temperature from 30 ⁰C to 20 ⁰C further enhanced fusion protein production. The highest expression level of 20aaVP3-VP1-Co1 was estimated to be 7.7 mg/L, which is comparable to other heterologous proteins produced using our S. cerevisiae expression system. Oral administration of the cell expressing 20aaVP3-VP1-Co1 induced VP1-specific IgG and IgA responses in mice. The S. cerevisiae-expressed 20aaVP3-VP1-Co1 fusion protein induced a significant immune response to the FMDV structural epitope protein, which opens the possibility of an oral FMDV vaccine.

Enhanced Effects of ISA 207 Adjuvant via Intradermal Route in Foot-and-Mouth Disease Vaccine for Pigs

In South Korea, a mandatory nation-wide foot-and-mouth disease (FMD) vaccination policy is in place. However, a major side effect of the current method of intramuscular (IM) administration of oil-adjuvanted FMD vaccines is the formation of granulomas in the muscles of pigs. To address this issue, we assessed the possible application of intradermal (ID) vaccination. Initially, we compared the serological immune response in specific pathogen-free pigs inoculated with FMD vaccines formulated with eight different adjuvants, administered twice at the neck site using a syringe with a needle via the ID route. Among the formulations (water-in-oil-in-water (W/O/W), oil-in-water (O/W), and polymer nanomaterials), ISA 207 of W/O/W was the most effective in inducing immunogenicity followed by ISA 201 of W/O/W. ISA 207 was further tested in formulations of different antigen doses (12 or 1.2 μg) delivered via both IM and ID routes. All four treatments successfully protected the pigs against FMD virus challenges. To assess the feasibility of the field application of the vaccines with ISA 207, we conducted ID vaccination of conventional pigs using a needle-free device, resulting in the detection of significant levels of neutralizing antibodies. ISA 207 was shown to be superior to ISA 201 in inducing immunogenicity via the ID route. In conclusion, ISA 207 could be a suitable adjuvant for ID vaccination in terms of vaccine efficacy for FMD, allowing for alternate use of ID vaccination and subsequent reduction in the incidences of granuloma formation in the field.

Unveiling the spatial distribution and transboundary pathways of FMD serotype O in Western China and its bordering countries

Foot-and-mouth disease (FMD) is a severe, highly contagious viral disease of livestock that has a significant economic impact on domestic animals and threatens wildlife survival in China and border countries. However, effective surveillance and prevention of this disease is often incomplete and unattainable due to the cost, the great diversity of wildlife hosts, the changing range and dynamics, and the diversity of FMDV. In this study, we used predictive models to reveal the spread and risk of FMD in anticipation of identifying key nodes to control its spread. For the first time, the spatial distribution of FMD serotype O was predicted in western China and border countries using a niche model, which is a combination of eco-geographic, human, topographic, and vegetation variables. The transboundary least-cost pathways (LCPs) model for ungulates in the study area were also calculated. Our study indicates that FMD serotype O survival is seasonal at low altitudes (March and June) and more sensitive to temperature differences at high altitudes. FMD serotype O risk was higher in Central Asian countries and both were highly correlated with the population variables. Ten LCPs were obtained representing Pakistan, Kazakhstan, Kyrgyzstan, and China.

Senecavirus cetus a novel picornavirus isolated from cetaceans represents a major host switching to the marine environment

Senecavirus A (SVA), an emerging virus that causes vesicular disease in swine, was, until recently, the only member of the Senecavirus genus (Picornaviridae). Here, we report the isolation and complete genome sequence of two isolates of cetacean picornavirus 1 (Senecavirus cetus), a novel picornavirus species of the Senecavirus genus from dead stranded cetaceans from Alaska. One isolate was from a harbor porpoise stranded in 2017, and another from a beluga whale, stranded in 2019. Whole-genome sequencing of Senecavirus cetus strains showed a genome-wide nucleotide identity of 98.8% and a genome size of 7455 nucleotides. The Senecavirus cetus genomes are most similar to SVA with a 58.3% genome-wide pairwise nucleotide identity. Infection of eleven available cell lines from terrestrial and aquatic animals showed that beluga and sheep cells were susceptible to infection by Senecavirus cetus. Phylogenetic and ancestral state reconstruction analyses supported the novel virus being a member of the Senecavirus genus and provided the first evidence of Senecavirus-like picornavirus infecting marine mammals and likely descending from a terrestrial host ancestor. These discoveries provided important information on the evolutionary relationships and taxonomy of picornaviruses and increased our understanding of the genomic characteristics and potential host range of Senecavirus cetus.

Susceptibility of primary ovine dorsal soft palate and palatine tonsil cells to FMDV infection

Foot and mouth disease (FMD) is a highly contagious viral disease affecting cloven-hoofed animals. This disease is one of the most important in animal health due to its significant socio-economic impact, especially in case of an outbreak. One important challenge associated with this disease is the ability of the FMD virus (FMDV) to persist in its hosts through still unresolved underlying mechanisms. The absence of relevant in vitro models is one factor preventing advancement in our understanding of FMDV persistence. While a primary bovine cell model has been established using cells from FMDV primary and persistence site in cattle, it appeared interesting to develop a similar model based on ovine anatomical sites of interest to compare host-pathogen interactions. Thus, epithelial cells derived from the palatine tonsils and the dorsal soft palate were isolated and cultured. Their epithelial nature was confirmed using immunofluorescence. Following monolayer infection with FMDV O/FRA/1/2001 Clone 2.2, the FMDV-sensitivity of these cells was evaluated. Dorsal soft palate (DSP) cells were also expanded in multilayers at the air-liquid interface to mimic a stratified epithelium sensitive to FMDV infection. Our investigation revealed the presence of infectious virus, as well as viral antigens and viral RNA, up to 35 days after infection of the cell multilayers. Further experiment with DSP cells from different individuals needs to be reproduced to confirm the robustness of the new model of persistence in multilayer DSP. The establishment of such primary cells creates new opportunities for FMDV research and analysis in sheep cells.

Multiple pathogens co-exposure and associated risk factors among cattle reared in a wildlife-livestock interface area in Kenya

Introduction

Understanding multi-pathogen infections/exposures in livestock is critical to inform prevention and control measures against infectious diseases. We investigated the co-exposure of foot-and-mouth disease virus (FMDV), Brucella spp., Leptospira spp., and Coxiella burnetii in cattle in three zones stratified by land use change and with different wildlife-livestock interactions in Narok county, Kenya. We also assessed potential risk factors associated with the transmission of these pathogens in cattle.

Methods

We identified five villages purposively, two each for areas with intensive (zone 1) and moderate wildlife-livestock interactions (zone 2) and one for locations with low wildlife-livestock interactions (zone 3). We sampled 1,170 cattle from 390 herds through a cross-sectional study and tested the serum samples for antibodies against the focal pathogens using enzyme-linked immunosorbent assay (ELISA) kits. A questionnaire was administered to gather epidemiological data on the putative risk factors associated with cattle's exposure to the investigated pathogens. Data were analyzed using the Bayesian hierarchical models with herd number as a random effect to adjust for the within-herd clustering of the various co-exposures among cattle.

Results

Overall, 88.0% (95% CI: 85.0-90.5) of the cattle tested positive for at least one of the targeted pathogens, while 41.7% (95% CI: 37.7-45.8) were seropositive to at least two pathogens. FMDV and Brucella spp. had the highest co-exposure at 33.7% (95% CI: 30.9-36.5), followed by FMDV and Leptospira spp. (21.8%, 95% CI: 19.5-24.4), Leptospira spp. and Brucella spp. (8.8%, 95% CI: 7.2-10.6), FMDV and C. burnetii (1.5%, 95% CI: 0.7-2.8), Brucella spp. and C. burnetii (1.0%, 95% CI: 0.3-2.2), and lowest for Leptospira spp. and C. burnetii (0.3%, 95% CI: 0.0-1.2). Cattle with FMDV and Brucella spp., and Brucella spp. and Leptospira spp. co-exposures and those simultaneously exposed to FMDV, Brucella spp. and Leptospira spp. were significantly higher in zone 1 than in zones 2 and 3. However, FMDV and Leptospira spp. co-exposure was higher in zones 1 and 2 than zone 3.

Discussion/conclusion

We recommend the establishment of a One Health surveillance system in the study area to reduce the morbidity of the targeted zoonotic pathogens in cattle and the risks of transmission to humans.

Assessment of Brazil's vesicular syndrome surveillance system: Profile of notifications and performance of the official veterinary service

Foot-and-mouth disease (FMD) is an ailment that causes serious damage to the productive chain, and its control through vaccination is of utmost importance for its eradication. Brazil initiated the National Foot-and-Mouth Disease Surveillance Program (PNEFA) with the aim of making the country FMD-free by 2026. As part of the program, notifications of vesicular lesions became mandatory for the Official Veterinary Service (OVS), which is responsible for verifying them. Due to its size, border areas with countries that do not have FMD-free status pose a risk to Brazil and require greater attention. This study described the profile of notifications of suspected outbreaks of vesicular syndrome in Brazil and analyzed the performance of the surveillance system. The results showed 7134 registered notifications of suspected vesicular syndrome outbreaks from 2018 to 2022, with 2022 having the highest number (n = 2343 or 32.85 %). The species that generated the most notifications were swine (90.99 %), cattle and buffaloes (7.54 %), goats and sheep (1.44 %), and others (0.03 %). The sources of notification were "Veterinary medicine professionals" (61.82 %), "Owners or employees" (13.66 %), "Third parties" (8.90 %), "OVS" (7.20 %), and "others" (2.66 %). 41.69 % of notifications originated from non-border municipalities, and 58.32 % from border areas. Only the state of Paraná account for 51.73 % of the total notifications. This state also accounted for 66.70 % of the 32.47 % of notifications with a final diagnosis of "absence of clinically compatible signs or susceptible animals", indicating a certain lack of knowledge in the area, leading to unnecessary notifications and system overload. The performance of the OVS was evaluated based on the service response time from notification registration trough Logistic and Negative binomial regressions. A total of 27.83 % of notifications did not meet the Brazilian legally specified time, and the zone related to the state of Parana needs improvements in performance. The presence and peaks of Senecavirus A cases may have influenced an increased number of swine notifications and led to a decrease in OVS response time. The results demonstrate better performance of surveillance in border areas. Given the vast territory of Brazil, it is not expected that 100 % of responses occur within the legal timeframe, however, the performance of the surveillance system proved to be adequate, with 86 % complied to the legislation. The performance indicators could be used as a monitoring tool, along with indicators to demonstrate system overload. Continued education actions are crucial for strengthening PNEFA.

Monoclonal antibody based solid phase competition ELISA to detect FMDV serotype A specific antibodies

In Foot-and-mouth disease (FMD) enzootic countries, periodic vaccination is the key tool in controlling the disease incidence. Active seromonitoring of the vaccinated population is critical to assess the impact of vaccination. Virus neutralization test (VNT) and enzyme-linked immunosorbent assays (ELISA) are commonly used for antibody detection. Assays like liquid phase blocking ELISA (LPBE) or solid phase competition ELISA (SPCE) are preferred as they do not require handling of live FMDV and are routinely used for seromonitoring or for vaccine potency testing; however, false positives are high in LPBE. Here we report, a monoclonal antibody (mAb) based SPCE as a potential alternate assay for antibody titration. From a panel of 12 mAbs against FMDV serotype A, two mAbs were chosen for the development of SPCE. Based on a set of 453 sera, it was demonstrated that mAb 2C4G11, mAb 6E8D11and polyclonal antibody (pAb) based SPCE had a relative sensitivity of 86.1, 86.1 and 80.3 %; and specificity of 99.6, 99.1 and 99.1 %, respectively. The correlation, repeatability, and level of agreement of the assays were high demonstrating the potential use of mAb in large scale surveillance studies and regular vaccine potency testing.

Establishment of the Foot-and-Mouth Disease Virus Type Asia1 Expressing the HiBiT Protein: A Useful Tool for a NanoBiT Split Luciferase Assay

Foot-and-mouth disease virus (FMDV) is a highly contagious virus that affects cloven-hoofed animals and causes severe economic losses in the livestock industry. Given that this high-risk pathogen has to be handled in a biosafety level (BSL)-3 facility for safety reasons and the limited availability of BSL-3 laboratories, experiments on FMDV call for more attention. Therefore, we aimed to develop an FMDV experimental model that can be handled in BSL-2 laboratories. The NanoBiT luciferase (Nano-luc) assay is a well-known assay for studying protein-protein interactions. To apply the NanoBiT split luciferase assay to the diagnosis and evaluation of FMD, we developed an inactivated HiBiT-tagged Asia1 Shamir FMDV (AS-HiBiT), a recombinant Asia1 shamir FMDV with HiBiT attached to the VP1 region of Asia1 shamir FMDV. In addition, we established LgBiT-expressing LF-BK cell lines, termed LgBit-LF-BK cells. It was confirmed that inactivated AS-HiBiT infected LgBiT-LF-BK cells and produced a luminescence signal by binding to the intracellular LgBiT of LgBiT-LF-BK cells. In addition, the luminescence signal became stronger as the number of LgBiT-LF-BK cells increased or the concentration of inactivated AS-HiBiT increased. Moreover, we confirmed that inactivated AS-HiBiT can detect seroconversion in sera positive for FMDV-neutralizing antibodies. This NanoBiT split luciferase assay system can be used for the diagnosis and evaluation of FMD and expanded to FMD-like virus models to facilitate the evaluation of FMDV vaccines and antibodies.

Centralized industrialization of pork in Europe and America contributes to the global spread of Salmonella enterica

Salmonella enterica causes severe food-borne infections through contamination of the food supply chain. Its evolution has been associated with human activities, especially animal husbandry. Advances in intensive farming and global transportation have substantially reshaped the pig industry, but their impact on the evolution of associated zoonotic pathogens such as S. enterica remains unresolved. Here we investigated the population fluctuation, accumulation of antimicrobial resistance genes and international serovar Choleraesuis transmission of nine pig-enriched S. enterica populations comprising more than 9,000 genomes. Most changes were found to be attributable to the developments of the modern pig industry. All pig-enriched salmonellae experienced host transfers in pigs and/or population expansions over the past century, with pigs and pork having become the main sources of S. enterica transmissions to other hosts. Overall, our analysis revealed strong associations between the transmission of pig-enriched salmonellae and the global pork trade.

Phylodynamic analysis of foot-and-mouth disease virus evolution in Mar Chiquita, Argentina

Foot-and-mouth disease is a highly contagious disease affecting cloven-hoofed animals, resulting in considerable economic losses. Its causal agent is foot-and-mouth disease virus (FMDV), a picornavirus. Due to its error-prone replication and rapid evolution, the transmission and evolutionary dynamics of FMDV can be studied using genomic epidemiological approaches. To analyze FMDV evolution and identify possible transmission routes in an Argentinean region, field samples that tested positive for FMDV by PCR were obtained from 21 farms located in the Mar Chiquita district. Whole FMDV genome sequences were obtained by PCR amplification in seven fragments and sequencing using the Sanger technique. The genome sequences obtained from these samples were then analyzed using phylogenetic, phylogeographic, and evolutionary approaches. Three local transmission clusters were detected among the sampled viruses. The dataset was analyzed using Bayesian phylodynamic methods with appropriate coalescent and relaxed molecular clock models. The estimated mean viral evolutionary rate was 1.17 × 10- 2 substitutions/site/year. No significant differences in the rate of viral evolution were observed between farms with vaccinated animals and those with unvaccinated animals. The most recent common ancestor of the sampled sequences was dated to approximately one month before the first reported case in the outbreak. Virus transmission started in the south of the district and later dispersed to the west, and finally arrived in the east. Different transmission routes among the studied herds, such as non-replicating vectors and close contact contagion (i.e., aerosols), may be responsible for viral spread.

Re-emergence of foot-and-mouth disease in the Republic of Korea caused by the O/ME-SA/Ind-2001e lineage

The O/ME-SA/Ind-2001e foot-and-mouth disease virus (FMDV) lineage is a pandemic strain that has recently become dominant within East and Southeast Asia. During May 2023, this viral lineage spread to the Republic of Korea, where 11 outbreaks were detected on cattle and goat farms located in Cheongju and Jeungpyeong. Infected animals displayed typical FMD signs including vesicular lesions with drooling and anorexia. Molecular diagnostic testing and genetic analysis (VP1 sequencing) showed that the causative FMDVs belonged to the O/ME-SA/Ind-2001e lineage and shared the closest nucleotide identity (97.95-99.21%) to viruses that have been collected from Mongolia and South-East Asian countries. Phylogenetic analyses showed that these sequences were distinct to those collected from the previous Korean O/ME-SA/Ind-2001e lineage outbreaks in 2019, demonstrating that these cases are due to a new incursion of the virus into the country. Prompt implementation of emergency vaccination using antigenically matched serotype O vaccines (r1 value: 0.74-0.93), together with intensive active surveillance on farms surrounding the infected premises has successfully prevented further spread of FMD. These recent FMD outbreaks reinforce the importance of research to understand the risks associated with transboundary pathways in the region, in order to reduce the possibility of a further reintroduction of FMD into the Republic of Korea.

Correlation between 146S Antigen Content in Foot-and-Mouth Disease Inactivated Vaccines and Immunogenicity Level and Vaccine Potency Alternative Test Methods

To investigate the association between 146S antigen contents in FMD inactivated vaccines and levels of antiviral immunity, this study vaccinated 30 kg pigs with three batches of FMD types O and A bivalent inactivated vaccines. Antibody titers and interferon-gamma (IFN-γ) secretion levels were measured on days 7, 14, 21, and 28 after primary immunization and on days 14 and 28 following booster immunization to assess associations between 146S contents and both antibody titers and IFN-γ secretion levels. Furthermore, 30 kg pigs were vaccinated with 46 batches of FMD type O inactivated vaccines and challenged on day 28, after which PD50 values were determined to evaluate the association between 146S content and PD50. The findings suggested that antibody titers and IFN-γ secretion levels at specific time points after immunization were positively associated with 146S contents. Additionally, 146S content showed a positive correlation with PD50, with greater PD50 values recorded for 146S contents ranging from 4.72 to 16.55 µg/dose. This investigation established a significant association between the 146S content in FMD inactivated vaccines and induced immune response against FMDV, thereby emphasizing its critical role in vaccine quality control. The determination of 146S content could serve as a new method for potency testing, offering an alternative to animal challenge tests.

Calcium Chloride as a Novel Stabilizer for Foot-and-Mouth Disease Virus and Its Application in the Vaccine Formulation

The thermal stability of the in-house-developed foot-and-mouth disease (FMD) type O and A viruses was evaluated, and the O Jincheon virus was found to exhibit the lowest thermal stability. To overcome this instability, we proposed a novel stabilizer, calcium chloride. The thermal stability of FMDVs increased up to a CaCl2 concentration of 10 mM, and it had a decreasing trend at >30 mM. The O Jincheon virus showed a significant decrease in the amount of antigen over time at 4 °C. In contrast, the samples treated with CaCl2 showed stable preservation of the virus without significant antigen loss. After the CaCl2-formulated vaccine was administered twice to pigs, the virus neutralization titer reached approximately 1:1000, suggesting that the vaccine could protect pigs against the FMDV challenge. In summary, the O Jincheon virus is difficult to utilize as a vaccine given its low stability during storage after antigen production. However, following its treatment with CaCl2, it can be easily utilized as a vaccine. This study evaluated CaCl2 as a novel stabilizer in FMD vaccines and may contribute to the development of stable vaccine formulations, especially for inherently unstable FMDV strains.

Cell Culture Adaptive Amino Acid Substitutions in FMDV Structural Proteins: A Key Mechanism for Altered Receptor Tropism

The foot-and-mouth disease virus is a highly contagious and economically devastating virus of cloven-hooved animals, including cattle, buffalo, sheep, and goats, causing reduced animal productivity and posing international trade restrictions. For decades, chemically inactivated vaccines have been serving as the most effective strategy for the management of foot-and-mouth disease. Inactivated vaccines are commercially produced in cell culture systems, which require successful propagation and adaptation of field isolates, demanding a high cost and laborious time. Cell culture adaptation is chiefly indebted to amino acid substitutions in surface-exposed capsid proteins, altering the necessity of RGD-dependent receptors to heparan sulfate macromolecules for virus binding. Several amino acid substations in VP1, VP2, and VP3 capsid proteins of FMDV, both at structural and functional levels, have been characterized previously. This literature review combines frequently reported amino acid substitutions in virus capsid proteins, their critical roles in virus adaptation, and functional characterization of the substitutions. Furthermore, this data can facilitate molecular virologists to develop new vaccine strains against the foot-and-mouth disease virus, revolutionizing vaccinology via reverse genetic engineering and synthetic biology.

Foot-and-Mouth Disease Virus Capsid Protein VP1 Antagonizes Type I Interferon Signaling via Degradation of Histone Deacetylase 5

Foot-and-mouth disease (FMD) is a highly contagious and economically important disease of cloven-hoofed animals that hampers trade and production. To ensure effective infection, the foot-and-mouth disease virus (FMDV) evades host antiviral pathways in different ways. Although the effect of histone deacetylase 5 (HDAC5) on the innate immune response has previously been documented, the precise molecular mechanism underlying HDAC5-mediated FMDV infection is not yet clearly understood. In this study, we found that silencing or knockout of HDAC5 promoted FMDV replication, whereas HDAC5 overexpression significantly inhibited FMDV propagation. IFN-β and IFN-stimulated response element (ISRE) activity was strongly activated through the overexpression of HDAC5. The silencing and knockout of HDAC5 led to an increase in viral replication, which was evident by decreased IFN-β, ISG15, and ISG56 production, as well as a noticeable reduction in IRF3 phosphorylation. Moreover, the results showed that the FMDV capsid protein VP1 targets HDAC5 and facilitates its degradation via the proteasomal pathway. In conclusion, this study highlights that HDAC5 acts as a positive modulator of IFN-β production during viral infection, while FMDV capsid protein VP1 antagonizes the HDAC5-mediated antiviral immune response by degrading HDAC5 to facilitate viral replication.

Complete genome characterization of foot-and-mouth disease virus My-466 belonging to the novel lineage O/ME-SA/SA-2018

Foot-and-mouth disease virus (FMDV), the causative agent of the foot-and-mouth disease of cattle population possesses a rapid evolutionary rate. In Bangladesh, the first circulation of the O/ME-SA/SA-2018 lineage as a novel sublineage, MYMBD21 was reported from our laboratory. The first whole genome sequence of an isolate, BAN/MY/My-466/2021 (shortly named My-466) of the SA-2018 lineage is characterized and represented in this study. The genome is 8216 nucleotides long with 6996 nucleotides open reading frame flanked by 5ꞌ UTR (1-1100) and 3ꞌ UTR (8097-8216). VP1 was found to be highly variable among the structural proteins with crucial mutations in the major antigenic region, G-H loop. Structural variations of the VP1 against both field and proposed local vaccine strains were evidenced by the G-H loop displacement in a superimposed 3D model. The complete genome information of the isolate would be valuable for undertaking proper control measures needed to limit the spread of the newly emerged FMDV strain.