Search Results (299)

Foot-and-mouth disease (FMD), bluetongue (BT), and Peste des Petits Ruminants (PPR) are major emerging and re-emerging viral infections affecting ruminants. These diseases can threaten livestock health, food security, and economic stability in low- and middle-income countries, including Algeria. However, their dynamics remain mostly unknown, limiting the implementation of effective preventive and control measures. We analyzed outbreak data reported by Algerian veterinary authorities and the WAHIS database from 2014 to 2022 for FMD; from 2006 to 2020 for BT; and from 2011 to 2022 for PPR to investigate their spatiotemporal patterns and environmental drivers. Over these periods, Algeria reported 1142 FMD outbreaks (10,409 cases; 0.16/1000 incidence), 167 BT outbreaks (602 cases; 0.018/1000), and 222 PPR outbreaks (3597 cases; 0.096/1000). Small ruminants were the most affected across all diseases, although cattle bore the highest burden of FMD. BT primarily impacted sheep, and PPR showed a higher incidence in goats. Disease peaks occurred in 2014 for FMD, 2008 for BT, and 2019 for PPR. Spatial analyses revealed distinct ecological hotspots: sub-humid and semi-arid zones for FMD and BT, and semi-arid/Saharan regions for PPR. These patterns may be influenced by species susceptibility, animal movement, trade, and climatic factors such as temperature and rainfall. The absence of consistent temporal trends and the persistence of outbreaks suggest multiple drivers, including insufficient vaccination coverage, under-reporting, viral evolution, and environmental persistence. Our findings underscore the importance of targeted species- and region-specific control strategies, including improved surveillance, cross-border coordination, and climate-informed risk mapping. Strengthening One Health frameworks will be essential to mitigate the re-emergence and spread of these diseases. Full article

Ovine herpesvirus 2 (OvHV-2) causes the fatal veterinary disease malignant catarrhal fever (MCF). Fusion is an essential step in the host cell entry of enveloped viruses and is an important target for vaccine development. OvHV-2 cannot be propagated in vitro, so a robust virus-free cell–cell membrane fusion assay is necessary to elucidate its entry mechanism. OvHV-2 cell–cell fusion requires three conserved herpesviral envelope glycoproteins: gB, gH, and gL. OvHV-2 fusion activity is detectable but low. We hypothesize that enhancing the cell surface expression of gB, which is the core herpesviral fusogen, will increase cell–cell fusion. We generated C-terminal truncation mutants of gB and determined their cell surface expression, subcellular distribution, and fusion activity. Two mutants, including one that lacked the entire cytoplasmic tail domain, failed to function in the cell–cell fusion assay, despite wild-type levels of surface expression. This suggests that the OvHV-2 gB cytoplasmic tail is critical for fusion. A gB mutant truncated at amino acid 847 showed increased surface expression and fusion relative to the wild type. This suggests that the robust fusion activity of gB847 is the result of increased surface expression. gB847 may be used in place of wild-type gB in an improved, more robust OvHV-2 fusion assay. Full article

Narrative review synthesizes the most current literature on the SARS-CoV-2 XEC variant, focusing on its genomic evolution, immune evasion characteristics, epidemiological dynamics, and public health implications. To achieve this, we conducted a structured search of the literature of peer-reviewed articles, preprints, and official surveillance data from 2023 to early 2025, prioritizing virological, clinical, and immunological reports related to XEC and its parent lineages. Defined by the distinctive spike protein mutations, T22N and Q493E, XEC exhibits modest reductions in neutralization in vitro, although current evidence suggests that mRNA booster vaccines, including those targeting JN.1 and KP.2, retain cross-protective efficacy against symptomatic and severe disease. The XEC strain of SARS-CoV-2 has drawn particular attention due to its increasing prevalence in multiple regions and its potential to displace other Omicron subvariants, although direct evidence of enhanced replicative fitness is currently lacking. Preliminary analyses also indicated that glycosylation changes at the N-terminal domain enhance infectivity and immunological evasion, which is expected to underpin the increasing prevalence of XEC. The XEC variant, while still emerging, is marked by a unique recombination pattern and a set of spike protein mutations (T22N and Q493E) that collectively demonstrate increased immune evasion potential and epidemiological expansion across Europe and North America. Current evidence does not conclusively associate XEC with greater disease severity, although additional research is required to determine its clinical relevance. Key knowledge gaps include the precise role of recombination events in XEC evolution and the duration of cross-protective T-cell responses. New research priorities include genomic surveillance in undersampled regions, updated vaccine formulations against novel spike epitopes, and long-term longitudinal studies to monitor post-acute sequelae. These efforts can be augmented by computational modeling and the One Health approach, which combines human and veterinary sciences. Recent computational findings (GISAID, 2024) point to the potential of XEC for further mutations in under-surveilled reservoirs, enhancing containment challenges and risks. Addressing the potential risks associated with the XEC variant is expected to benefit from interdisciplinary coordination, particularly in regions where genomic surveillance indicates a measurable increase in prevalence. Full article

The growth of aquaculture production in recent years has revealed multiple challenges, including the rise of antimicrobial resistance (AMR) in aquatic animal production, which is currently attracting significant attention from multiple one-health stakeholders. While antibiotics have played a major role in the treatment of bacterial infections for almost a century, a major consequence of their use is the increase in AMR, including the emergence of AMR in aquaculture. The AMR phenomenon creates a situation where antibiotic use in one system (e.g., aquaculture) may impact another system (e.g., terrestrial–human). Non-prudent use of antibiotics in aquaculture and animal farming increases the risk of AMR emergence, since bacteria harboring antibiotic resistance genes can cross between compartments such as wastewater or other effluents to aquatic environments, including intensive aquaculture. Transferable antimicrobial resistance gene (AMG) elements (plasmids, transposons, integrons, etc.) have already been detected in varying degrees from pathogenic bacteria that are often causing infections in farmed fish (Aeromonas, Vibrio, Streptococcus, Pseudomonas, Edwardsiella, etc.). This review of current veterinary approaches for the prevention and control of AMR emergence in aquaculture focuses on the feasibility of alternatives to antimicrobials and supplemental treatment applications during on-farm bacterial disease control and prevention. The use of vaccines, bacteriophages, biosurfactants, probiotics, bacteriocins, and antimicrobial peptides is discussed. Full article

Clostridium novyi is a common pathogen in domestic animals and humans, and alpha-toxin is the main cause of its pathogenesis. Because it is a fastidious organism, obtaining alpha-toxin is expensive. Therefore, we proposed an in silico study to synthesize epitopes in cultures of Escherichia coli BL21 pLysS (DE3). First, we used a stirred-tank bioreactor, developing a dry mass yield (DMY) of 0.77 g/L in batch cultures and 1.03 g/L in fed-batch cultures, without acetic acid production. With scale-up using a system without mechanical agitation, there was a higher DMY (1.20 g/L) with 0.56 mmol/mL of alpha-toxin epitope 1 (DE3/Ep1) and 0.61 mmol/mL of alpha-toxin epitope 2 (DE3/Ep2), with a similar profile for O2 consumption, glucose, and no acetic acid production. The kinetic parameters µ(h⁻¹), YX/S, YP/S, QP, and QX did not differ significantly; however, the kinetic data were superior. Our results suggest that in silico tools allow epitope selection and bioprocess standardization. This system provides cost savings and technological advances for the veterinary vaccine industry. Full article

On 11 March 2020, the World Health Organisation (WHO) declared a global pandemic caused by the SARS-CoV-2 coronavirus that earlier in February 2020 the WHO had named COVID-19 (coronavirus disease 2019). There were neither drugs nor vaccines that were known to be effective against the virus, stimulating an urgent worldwide search for treatments. An evaluation of existing drugs by ‘repurposing’ was initiated followed by a transition to de novo drug discovery. Repurposing of an already approved drug may accelerate the introduction of that drug into clinical use by circumventing early, including preclinical studies otherwise essential for a de novo drug and reducing development costs. Early in the pandemic three drugs were identified as repurposing candidates for the treatment of COVID-19: (i) hydroxychloroquine, an anti-malarial also used to treat rheumatoid arthritis and lupus; (ii) ivermectin, an antiparasitic approved for both human and veterinary use; (iii) remdesivir, an anti-viral originally developed to treat hepatitis C. The scientific evidence, both for and against the efficacy of these three drugs as treatments for COVID-19, vied with public demand and politicization as unqualified opinions clashed with evidence-based medicine. To quote Hippocrates, “There are in fact two things, science and opinion; the former begets knowledge, the latter ignorance”. Full article

This review examines the potential and challenges of using hydrogel vaccine delivery systems in animal immunization. Traditional methods face issues like low immunogenicity, reliance on cold chains, and inefficient delivery, limiting their use in modern animal husbandry. Hydrogels offer a promising solution due to their biocompatibility, controlled drug release, and immune regulation. This paper highlights hydrogels’ benefits, such as mimicking natural infection through sustained antigen release, boosting antigen-presenting cell activity, activating immune responses, and forming barriers at mucosal sites to prevent pathogen invasion. Additionally, innovative delivery methods like microneedle patches and nasal sprays show promise in enhancing convenience and compliance in animal vaccination. By combining interdisciplinary efforts and technological advancements, the hydrogel vaccine delivery system is anticipated to be crucial in preventing animal diseases, supporting sustainable animal husbandry, and ensuring global animal health and food safety. Full article

Lyssaviruses are RNA viruses in the Family Rhabdoviridae, Genus Lyssavirus. They represent the causative agents of acute, progressive encephalitis, known historically as rabies. Regardless of specific etiology, their collective viral morphology, biochemistry, pathobiology, associated clinical signs, diagnosis, epizootiology, and management are essentially the same. Despite centuries of clinical recognition, these quintessential neurotropic agents remain significant pathogens today, with substantive consequences to agriculture, public health, and conservation biology. Notably, the singular morbidity caused by lyssaviruses is incurable and constitutes the highest case fatality of any viral disease. All warm-blooded vertebrates are believed to be susceptible. The dog is the only domestic animal that serves as a reservoir, vector, and victim. In contrast, felids are effective vectors, but not reservoirs. All other rabid domestic species, such as livestock, constitute spillover infections, as a bellwether to local lyssavirus activity. Frequently, professional confusion abounds among the veterinary community, because although the viral species Lyssavirus rabies is inarguably the best-known representative in the Genus, at least 20 other recognized or putative members of this monophyletic group are known. Frequently, this is simply overlooked. Moreover, often the ‘taxonomic etiology’ (i.e., ‘Lyssavirus x’) is mistakenly referenced in a biopolitcal context, instead of the obvious clinical illness (i.e., ‘rabies’). Global consternation persists, if localities believe they are ‘disease-free’, when documented lyssaviruses circulate or laboratory-based surveillance is inadequate to support such claims. Understandably, professional chagrin develops when individuals mistake the epidemiological terminology of control, prevention, elimination, etc. Management is not simple, given that the only licensed veterinary and human vaccines are against rabies virus, sensu lato. There are no adequate antiviral drugs for any lyssaviruses or cross-reactive biologics developed against more distantly related viral members. While representative taxa among the mammalian Orders Chiroptera, Carnivora, and Primates exemplify the major global reservoirs, which mammalian species are responsible for the perpetuation of other lyssaviruses remains a seemingly academic curiosity. This zoonosis is neglected. Clearly, with such underlying characteristics as a fundamental ‘disease of nature’, rabies, unlike smallpox and rinderpest, is not a candidate for eradication. With the worldwide zeal to drive human fatalities from canine rabies viruses to zero by the rapidly approaching year 2030, enhanced surveillance and greater introspection of the poorly appreciated burden posed by rabies virus and diverse other lyssaviruses may manifest as an epidemiological luxury to the overall global program of the future. Full article

Background/Objective: Virus-based vaccine vectors have been widely utilised in commercial vaccines, predominantly for virus infections. They also offer promise for bacterial diseases, for which many vaccines are sub-optimal or ineffective. It is well-established for chlamydial infections, including ovine enzootic abortion, that the major outer membrane protein (MOMP) antigen is protective. Immune responses strongly associated with controlling Chlamydiae include cellular interferon-gamma (IFN-γ) production. Methods: A study was conducted to compare the ability of a modified Orf virus vector directly with a modified sheep maedi visna virus vector to deliver the C. abortus antigen ompA and stimulate vaccine-induced responses in sheep. The Orf virus-based vaccine (mORFV-ompA) was found to be more effective in stimulating MOMP-specific antibodies and cellular antigen-driven IFN-γ in immunised sheep. This mORFV-ompA vaccine was assessed in a follow-up immunogenicity investigation in sheep, where the cellular and humoral immune responses elicited following immunisation with the live or inactivated vaccine were determined. Sheep were immunised intramuscularly with a live mORFV-ompA (n = 10) or an inactivated mORFV-ompA (n = 10). An additional group of 10 sheep served as unvaccinated controls. Results: Serological anti-MOMP antibodies and cellular recall responses of peripheral blood mononuclear cells to the native C. abortus antigen were assessed. Immunisation with either the live or inactivated mORFV-ompA-induced anti-MOMP immunoglobulin-G. Antigen-specific cellular responses, characterised by the secretion of IFN-γ and interleukin (IL)-17A, with negligible IL-10 and no IL-4, were detected in lymphocyte stimulation assays from both mORFV groups. No antibody responses to the mORFV platform were detected following immunisations. Conclusions: Both live and inactivated vaccines have the potential to be a platform technology for deployment in sheep. This addresses a notable gap in veterinary vaccine development where the induction of both humoral responses and cellular responses is required without using an adjuvant. The successful use of the MOMP candidate antigen suggests potential utility for bacterial disease deployment. Full article

Monitoring infectious diseases is essential for safeguarding equine health and ensuring the sustainability of the horse industry. In 2019, the Royal Veterinary Association of the Netherlands (KNMvD) and Royal GD (GD Animal Health) launched SEIN (Surveillance of Equine Infectious diseases in the Netherlands), a voluntary surveillance system for laboratory-confirmed outbreaks of equid alphaherpesvirus 1 (EHV-1), equid alphaherpesvirus 4 (EHV-4), equine influenza virus (EIV), and Streptococcus equi subsp. equi. This retrospective study analyzed 364 confirmed outbreaks reported through SEIN between June 2019 and April 2023. S. equi was the most commonly reported pathogen overall (64%). Among outbreaks involving respiratory disease, S. equi accounted for 74% of cases, followed by EHV-4 (16%), EIV (6%), and EHV-1 (4%). The geographical distribution of outbreaks covered 80 of the 90 postal code regions (89%), and approximately half of all participating practices generated at least 1 alert. Vaccination data revealed low coverage against EHV-1/4, EIV, and S. equi among both affected horses and premises. Clinical signs overlapped between pathogens, but some were more pathogen-specific, e.g., coughing in EIV, and abscessation in S. equi. The SEIN system provided spatiotemporal information on confirmed outbreaks. These results underscore the importance of quick diagnostics and structured surveillance systems in guiding prevention strategies. Full article

Canine distemper virus (CDV) is a highly contagious disease with high morbidity and mortality rates in veterinary medicine. This retrospective study aimed to identify epidemiological characteristics and potential risk factors associated with CDV infection in dogs exhibiting neurological manifestations. The diagnosis was confirmed through immunochromatographic antigen testing, RT-PCR, or Lentz corpuscles identification. Dogs diagnosed with central nervous system (CNS) disorders unrelated to CDV served as the control group. Age, breed, weight, sex, and neuter status were compared between groups using logistic regression (p < 0.05), the log-likelihood method, and log odds ratio (LOR) calculations. Clinical signs, seasonality, and vaccination protocols were documented. Prevalence, mortality, lethality, and survival rates were determined. Younger dogs (p = 0.00690; LOR = −0.01438) and Shih Tzu (p = 0.00007; LOR = 1.53774) and Lhasa Apso (p = 0.000264; LOR = 1.76084) showed a significantly increased likelihood of developing neurological signs due to CDV infection. Most CDV-infected dogs exhibited multifocal CNS involvement and accompanying extra-neural signs. The highest occurrence of CDV-related neurological signs was recorded in autumn. Many infected dogs had an updated vaccination protocol. The prevalence of dogs with CDV was 4.72%. Mortality and lethality rates were 1.94% and 47.06%, respectively. The median survival time was 754 days. The identified epidemiological characteristics and risk factors provide essential insights for improving preventive strategies against CDV infection. Full article

This study examined the socioeconomic and veterinary cost factors influencing dog abandonment and adoption outcomes across 162 regions in the Republic of Korea from 2021 to 2023. Unlike prior research, this study distinguished between intentionally abandoned dogs and those lost and subsequently returned to their owners, normalizing abandonment data by population. Using publicly available regional data and spatial regression models, we found that the number of people receiving unemployment benefits was consistently and negatively associated with the number of dog abandonments per 100,000 residents, which was normalized by total population to avoid potential errors. Rabies vaccination costs were also negatively associated with abandonment. In contrast, comprehensive income tax amounts—a proxy for regional wealth—were positively correlated with the percentage of dog abandonments reported in 2021 and 2023. Spatial Lag Models accounted for over 50% of the variance in the number of dog abandonments, confirming spatial dependence and highlighting the importance of geographically targeted animal welfare interventions. However, spatial patterns in adoption were less consistent. These findings highlight the importance of incorporating economic and spatial considerations into the design of public policies and shelter strategies to mitigate dog abandonment and enhance adoption outcomes. Full article

Canine papillomavirus (CPV) infection leads to a range of clinical manifestations from benign warts to malignant tumors in dogs, posing significant challenges in veterinary medicine due to its diverse genotypic spectrum. This study introduced broad-range and robust polymerase chain reaction (PCR) assays designed to enhance the detection, identification, and quantification of multiple CPV genotypes. By using both universal and genotype-specific primers, this protocol significantly improved diagnostic specificity and sensitivity across the 23 known CPV genotypes compared to previously described ones. The primers were designed to target conserved regions across all genotypes for general detection, as well as specific regions in the predominant genotypes CPV1 and CPV2 for detailed analysis. Validation of this protocol using synthetic plasmids and clinical samples confirmed its enhanced performance over traditional methods, as demonstrated by higher specificity and sensitivity. Additionally, the application of this PCR approach in a series of epidemiological studies provided novel insights into the distribution and prevalence of CPV genotypes, highlighting its potential utility in shaping targeted vaccination and clinical management strategies. Furthermore, the quantitative capability of this established protocol allowed for monitoring viral loads in clinical cases, offering a valuable tool for assessing treatment efficacy and disease progression. Further validation through larger-scale clinical studies will be crucial to substantiate the diagnostic accuracy and epidemiological value of the assays. Full article

Adenoviral (AdV) vector-based vaccines employing the human AdV (HAdV) and chimpanzee AdV (ChAdV) vector platforms played a crucial role in combating the COVID-19 pandemic. However, the widespread use of these platforms, the prevalence of various HAdV types, and the resulting preexisting immunity have significantly impacted the vaccines utilizing these vector platforms. Considering these challenges, the bovine AdV type 3 (BAdV-3) vector system has emerged as a versatile and innovative platform for developing next-generation vaccines against infectious diseases. Inherent attributes like a high transduction efficiency, large transgene insertion capacity, broad tissue tropism, and robust induction of innate immunity add significant value to the BAdV vector platform for vaccine design. BAdV-3 vectors effectively elude HAdV-specific preexisting humoral and cellular immune responses. Additionally, BAdV-3 is low in pathogenicity for its host and is anticipated to be safe as a vaccine platform. This systematic review provides an overview of the development of BAdV-3 as a vaccine delivery platform and its application in designing vaccines for infectious agents of human and veterinary importance. Full article

Greater Bangkok, Thailand, has large numbers of both owned and free-roaming dogs, two populations that intersect and overlap in complex and nuanced ways. A more robust understanding of owned dog populations is, therefore, important not only in supporting the welfare of owned dogs but also in managing free-roaming dog populations and protecting human health through the prevention of rabies transmission. Over 3200 residents were surveyed to explore the numbers and demographics of owned dogs in Greater Bangkok, plus owners’ attitudes and reported behaviours related to their dogs; the acquisition and loss of owned dogs; and caretaking by owners (confinement practices, sterilisation, rabies vaccination, and other veterinary care). The study also considered dog owners’ practices in relation to a Catch, Neuter, Vaccinate, Return (CNVR) programme designed to humanely manage dog populations and vaccinate dogs against rabies. Survey results indicate that there are approximately 1.3 million owned dogs in Greater Bangkok. Key findings include high reported rabies vaccination among owned dogs (84% in the past year). Fifty-three percent of owned dogs in the sample were reported to be sterilised, 66% were allowed to roam, and 46% of dogs acquired into households were adopted from the street. The CNVR programme appeared to impact the care and keeping of owned dogs in the community, as it was associated with greater confinement and sterilisation levels. Full article