RESUMO
Equine influenza virus (EIV) remains a threat to horses, despite the availability of vaccines. Strategies to monitor the virus and prevent potential vaccine failure revolve around serological assays, RT-qPCR amplification, and sequencing the viral hemagglutinin (HA) and neuraminidase (NA) genes. These approaches overlook the contribution of other viral proteins in driving virulence. This study assesses the potential of long-read nanopore sequencing for fast and precise sequencing of circulating equine influenza viruses. Therefore, two French Florida Clade 1 strains, including the one circulating in winter 2018-2019 exhibiting more pronounced pathogenicity than usual, as well as the two currently OIE-recommended vaccine strains, were sequenced. Our results demonstrated the reliability of this sequencing method in generating accurate sequences. Sequence analysis of HA revealed a subtle antigenic drift in the French EIV strains, with specific substitutions, such as T163I in A/equine/Paris/1/2018 and the N188T mutation in post-2015 strains; both substitutions were in antigenic site B. Antigenic site E exhibited modifications in post-2018 strains, with the N63D substitution. Segment 2 sequencing also revealed that the A/equine/Paris/1/2018 strain encodes a longer variant of the PB1-F2 protein when compared to other Florida clade 1 strains (90 amino acids long versus 81 amino acids long). Further biological and biochemistry assays demonstrated that this PB1-F2 variant has enhanced abilities to abolish the mitochondrial membrane potential ΔΨm and permeabilize synthetic membranes. Altogether, our results highlight the interest in rapidly characterizing the complete genome of circulating strains with next-generation sequencing technologies to adapt vaccines and identify specific virulence markers of EIV.
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Doenças dos Cavalos , Vírus da Influenza A Subtipo H3N8 , Infecções por Orthomyxoviridae , Vacinas , Animais , Aminoácidos/genética , Genômica , Cavalos , Vírus da Influenza A Subtipo H3N8/genética , Infecções por Orthomyxoviridae/veterinária , Reprodutibilidade dos Testes , Análise de Sequência/veterinária , Fatores de VirulênciaRESUMO
Vaccination is one of the most widely used strategies to protect horses against pathogens. However, available equine vaccines often have limitations, as they do not always provide effective, long-term protection and booster injections are often required. In addition, research efforts are needed to develop effective vaccines against emerging equine pathogens. In this review, we provide an inventory of approved adjuvants for equine vaccines worldwide, and discuss their composition and mode of action when available. A wide range of adjuvants are used in marketed vaccines for horses, the main families being aluminium salts, emulsions, polymers, saponins and ISCOMs. We also present veterinary adjuvants that are already used for vaccination in other species and are currently evaluated in horses to improve equine vaccination and to meet the expected level of protection against pathogens in the equine industry. Finally, we discuss new adjuvants such as liposomes, polylactic acid polymers, inulin, poly-ε-caprolactone nanoparticles and co-polymers that are in development. Our objective is to help professionals in the horse industry understand the composition of marketed equine vaccines in a context of mistrust towards vaccines. Besides, this review provides researchers with a list of adjuvants, either approved or at least evaluated in horses, that could be used either alone or in combination to develop new vaccines.
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Adjuvantes Imunológicos , Nanopartículas , Cavalos , Animais , Adjuvantes Imunológicos/farmacologia , Vacinação/veterinária , Nanopartículas/uso terapêutico , PolímerosRESUMO
Equine herpesvirus 1 isolates from a 2021 outbreak of neurologic disease in Europe have a mutation, A713G, in open reading frame 11 not detected in 249 other sequences from equine herpesvirus 1 isolates. This single-nucleotide polymorphism could help identify horses infected with the virus strain linked to this outbreak.
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Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Animais , Monitoramento Epidemiológico , Europa (Continente)/epidemiologia , Infecções por Herpesviridae/epidemiologia , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/epidemiologia , Cavalos/virologia , Fases de Leitura AbertaRESUMO
A herd of seven captive-born Grevy's zebras (Equus grevyi) experienced an outbreak of nasal discharge and sneezing. Clinical signs, including lethargy and anorexia, were severe and acute in three animals, including a 16-mo-old male that died within 48 h. Treatment of two severely affected zebras included valacyclovir (40 mg/kg PO), meloxicam (0.6 mg/kg IM/PO), and cefquinome (2.5 mg/kg IM q48h). An adult female improved rapidly, and clinical signs resolved within 48 h of treatment. Administration of valacyclovir pellets was very complicated in a 2-mo-old female, and death occurred within 48 h. Histologic examination of the two individuals that died revealed severe fibrinonecrotic interstitial pneumonia with prominent hyaline membranes and type II pneumocyte hyperplasia. Additionally, the 16-mo-old male presented systemic endothelial activation with vascular thrombosis and necrosis and mild nonsuppurative meningoencephalitis. Herpesviral DNA was detected in the lungs of both individuals by nested polymerase chain reaction. The nucleic acid sequence of the amplicons showed 100% similarity with previously published equid alphaherpesvirus 9 sequences. Three additional animals developed mild nasal discharge only and recovered spontaneously. The zebras shared housing facilities with other species, including white rhinoceros (Ceratotherium simum), reticulated giraffe (Giraffa camelopardalis reticulata), and several antelope species. None of these animals showed clinical signs. Additionally, nasal swabs and whole blood samples were collected from cohoused white rhinoceroses (n = 3) and springboks (Antidorcas marsupialis, n = 3) as well as nasal swabs from cohoused reticulated giraffes (n = 4). Nucleic acid sequence from equid herpesviruses was not detected in any of these samples. The source of the infection in the zebras remains unclear.
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Surtos de Doenças/veterinária , Equidae , Infecções por Herpesviridae/veterinária , Varicellovirus/classificação , Animais , Animais de Zoológico , Antivirais/uso terapêutico , Feminino , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/patologia , Infecções por Herpesviridae/virologia , Masculino , Valaciclovir/uso terapêuticoRESUMO
BACKGROUND: Avoidance of antigenic stimuli was found to significantly reverse airway obstruction of horses with severe equine asthma (sEA). To date, no published study investigated the influence of steaming hay on lower airway condition of sEA-affected horses. The objectives were to determine the clinical, cytological and cytokine respiratory responses of both sEA and control (CTL) horses experimentally exposed to steamed or dry hay. RESULTS: A cohort of 6 sEA horses and 6 CTL horses was involved in this field study. On day 0, both groups were fed with steamed hay for 5 consecutive days, followed by a wash-out period of 26 days prior to be fed with dry hay for 5 consecutive days. Investigations performed 2 days prior to and 5 days after each challenge included clinical score, tracheal mucus accumulation, and bronchoalveolar lavage fluid (BALF) cytology and cytokine mRNA expression. Feeding steamed hay significantly decreased its mould content (P < 0.001). Mucus score significantly increased when feeding dry hay (P = 0.01). No significant influence of challenge type was found on clinical score. Percentages of neutrophils (P < 0.001) as well as mRNA expression of IL-1ß (P = 0.024), IL-6R (P = 0.021), IL-18 (P = 0.009) and IL-23 (P = 0.036) in BALF of sEA affected horses were significantly increased after both (steamed and dry hay) challenges. Relative mRNA expression of IL-1ß, IL-6R and IL-23 in BALF were also significantly correlated to neutrophil percentages and both clinical and tracheal mucus score. CONCLUSIONS: Steaming significantly decreased mould content but inconsistently influenced the respiratory response of sEA affected horses when fed hay. Based on BALF cytology and cytokine profiles, its relevance might be controversial as a non-medicinal therapy for sEA-affected horses.
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Ração Animal , Asma/veterinária , Doenças dos Cavalos/prevenção & controle , Microbiologia do Ar , Ração Animal/efeitos adversos , Animais , Asma/etiologia , Asma/imunologia , Asma/prevenção & controle , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/metabolismo , Feminino , Doenças dos Cavalos/etiologia , Doenças dos Cavalos/imunologia , Cavalos/imunologia , Masculino , Vapor , Traqueia/metabolismoRESUMO
BACKGROUND: The potential involvement of viruses in inflammatory airway disease (IAD) was previously investigated through either serology or PCR from nasopharyngeal swabs (NS). The aims of this study were to determine the prevalence and incidence of viral genome detection by qPCR in the equine airways, and their association with respiratory clinical signs. METHODS: Both NS and tracheal washes (TW) were collected monthly on 52 Standardbred racehorses at training, over 27 consecutive months (581 samples). Equid herpesviruses (EHV)-1, -4, -2 and -5, equine rhinitis virus-A and -B (ERBV), equine adenovirus-1 and -2, equine coronavirus and equine influenza virus were systematically investigated in both NS and TW. Nasal discharge, coughing, tracheal mucus score and TW neutrophil proportions were simultaneously recorded. RESULTS: Genome for 7/10 viruses were detected at least once throughout the study; up to 4 different viruses being also concomitantly detected. Monthly incidence in TW was respectively 27.9% (EHV-5), 24.8% (EHV-2), 7.1% (ERBV), 3.8% (EHV-4), 1.9% (EAdV1) and 0.2% (EHV-1; ERAV). Neither agreement nor correlation between NS and TW was found for respectively genome detection and viral loads. Detection of viral genome in NS was not associated with any clinical sign. Coughing was significantly associated with TW detection of EHV-2 DNA (OR 3.1; P = 0.01) and ERBV RNA (OR 5.3; P < 0.001). Detection of EHV-2 DNA in TW was also significantly associated with excess tracheal mucus (OR 2.1; P = 0.02). CONCLUSIONS: Detection and quantification of EHV-2 and ERBV by qPCR in TW, but not in NS, should be considered when investigating horses with IAD.
Assuntos
Doenças dos Cavalos/diagnóstico , Inflamação/veterinária , Técnicas de Diagnóstico Molecular/métodos , Infecções Respiratórias/veterinária , Medicina Veterinária/métodos , Viroses/veterinária , Vírus/isolamento & purificação , Animais , Feminino , Cavalos , Incidência , Inflamação/diagnóstico , Inflamação/epidemiologia , Masculino , Nasofaringe/virologia , Prevalência , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Traqueia/virologia , Viroses/epidemiologia , Viroses/virologia , Vírus/classificação , Vírus/genéticaRESUMO
Equine arteritis virus (EAV) is the causative agent of equine viral arteritis, a disease observed only in equids. EAV is the prototype of the family Arteriviridæ within the order Nidovirales. EAV is an enveloped, positive-sense, single-stranded RNA virus with a considerable variation in the genome as observed in other RNA viruses. During natural infections, EAV may cause abortion and persistent subclinical infections in stallions which can shed the virus in the semen for years, or even lifetime. Chronically infected stallions represent the natural reservoir of the virus. They ensure the persistence and the evolution of the virus, making possible the emergence of new variants potentially virulent. The genetic heterogeneity of EAV during persistent infection in the stallion is considerably greater than that generated during epidemics. Recent studies facilitated the understanding of EAV evolution and genetic variability. With recent advances in molecular biological techniques and the increasing number of sequences available in databases, molecular epidemiological studies have reported specific molecular hallmarks of EAV strains during and outside of epidemics. These new data should facilitate a better understanding and the determination of the origin of new EAV outbreaks.
RESUMO
Infection with equid herpesvirus 1 (EHV-1), a DNA virus of the Herpesviridae family represents a significant welfare issue in horses and a great impact on the equine industry. During EHV-1 infection, entry of the virus into different cell types is complex due to the presence of twelve glycoproteins (GPs) on the viral envelope. To investigate virus entry mechanisms, specific combinations of GPs were pseudotyped onto lentiviral vectors. Pseudotyped virus (PV) particles bearing gB, gD, gH and gL were able to transduce several target cell lines (HEK293T/17, RK13, CHO-K1, FHK-Tcl3, MDCK I & II), demonstrating that these four EHV-1 glycoproteins are both essential and sufficient for cell entry. The successful generation of an EHV-1 PV permitted development of a PV neutralisation assay (PVNA). The efficacy of the PVNA was tested by measuring the level of neutralising serum antibodies from EHV-1 experimentally infected horses (n = 52) sampled in a longitudinal manner. The same sera were assessed using a conventional EHV-1 virus neutralisation (VN) assay, exhibiting a strong correlation (r = 0.82) between the two assays. Furthermore, PVs routinely require -80 °C for long term storage and a dry ice cold-chain during transport, which can impede dissemination and utilisation in other stakeholder laboratories. Consequently, lyophilisation of EHV-1 PVs was conducted to address this issue. PVs were lyophilised and pellets either reconstituted immediately or stored under various temperature conditions for different time periods. The recovery and functionality of these lyophilised PVs was compared with standard frozen aliquots in titration and neutralisation tests. Results indicated that lyophilisation could be used to stably preserve such complex herpesvirus pseudotypes, even after weeks of storage at room temperature, and that reconstituted EHV-1 PVs could be successfully employed in antibody neutralisation tests.
Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Herpesvirus Equídeo 4 , Doenças dos Cavalos , Humanos , Animais , Cavalos , Herpesvirus Equídeo 1/genética , Células HEK293 , Anticorpos Antivirais , Anticorpos Neutralizantes , Infecções por Herpesviridae/veterinária , Glicoproteínas , Herpesvirus Equídeo 4/genéticaRESUMO
Equid herpesvirus 4 (EHV-4) is a common respiratory pathogen in horses. It sporadically induces abortion or neonatal death. Although its contribution in neurological disorders is not clearly demonstrated, there is a strong suspicion of its involvement. Despite preventive treatments using vaccines against EHV-1/EHV-4, the resurgence of alpha-EHV infection still constitutes an important threat to the horse industry. Yet very few studies have been conducted on the search for antiviral molecules against EHV-4. A screening of 42 antiviral compounds was performed in vitro on equine fibroblast cells infected with the EHV-4 405/76 reference strain (VR2230). The formation of cytopathic effects was monitored by real-time cell analysis (RTCA), and the viral load was quantified by quantitative PCR. Aciclovir, the most widely used antiviral against alpha-herpesviruses in vivo, does not appear to be effective against EHV-4 in vitro. Potential antiviral activities were confirmed for eight molecules (idoxuridine, vidarabine, pritelivir, cidofovir, valganciclovir, ganciclovir, aphidicolin, and decitabine). Decitabine demonstrates the highest efficacy against EHV-4 in vitro. Transcriptomic analysis revealed the up-regulation of various genes implicated in interferon (IFN) response, suggesting that decitabine triggers the immune antiviral pathway.
Assuntos
Antivirais , Decitabina , Infecções por Herpesviridae , Herpesvirus Equídeo 4 , Doenças dos Cavalos , Imunidade Inata , Animais , Antivirais/farmacologia , Linhagem Celular , Decitabina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Fibroblastos/efeitos dos fármacos , Fibroblastos/virologia , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/virologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/imunologia , Herpesvirus Equídeo 4/efeitos dos fármacos , Doenças dos Cavalos/virologia , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/imunologia , Cavalos , Imunidade Inata/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacosRESUMO
Reports of newly discovered equine hepatotropic flavi- and parvoviruses have emerged throughout the last decade in many countries, the discovery of which has stimulated a great deal of interest and clinical research. Although commonly detected in horses without signs of disease, equine parvovirus hepatitis (EqPV-H) and equine hepacivirus (EqHV) have been associated with liver disease, including following the administration of contaminated anti-toxin. Our aim was to determine whether EqPV-H and EqHV are present in Australian horses and whether EqPV-H was present in French horses and to examine sequence diversity between strains of both viruses amongst infected horses on either side of the globe. Sera from 188 Australian horses and 256 French horses from horses with and without clinical signs of disease were collected. Twelve out of 256 (4.7%) and 6 out of 188 (3.2%) French and Australian horses, respectively, were positive for the molecular detection of EqPV-H. Five out of 256 (1.9%) and 21 out of 188 (11.2%) French and Australian horses, respectively, were positive for the molecular detection of EqHV. Australian strains for both viruses were genomically clustered, in contrast to strains from French horses, which were more broadly distributed. The findings of this preliminary survey, with the molecular detection of EqHV and EqPV-H in Australia and the latter in France, adds to the growing body of awareness regarding these recently discovered hepatotropic viruses. It has provided valuable information not just in terms of geographic endemicity but will guide equine clinicians, carers, and authorities regarding infectious agents and potential impacts of allogenic tissue contamination. Although we have filled many gaps in the world map regarding equine hepatotropic viruses, further prospective studies in this emerging field may be useful in terms of elucidating risk factors and pathogenesis of these pathogens and management of cases in terms of prevention and diagnosis.
Assuntos
Hepacivirus , Hepatite Viral Animal , Doenças dos Cavalos , Infecções por Parvoviridae , Parvovirus , Filogenia , Animais , Cavalos , Doenças dos Cavalos/virologia , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/sangue , Austrália/epidemiologia , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Infecções por Parvoviridae/sangue , França/epidemiologia , Hepatite Viral Animal/virologia , Hepatite Viral Animal/epidemiologia , Hepatite Viral Animal/sangue , Parvovirus/genética , Parvovirus/isolamento & purificação , Parvovirus/classificação , Parvovirus/imunologia , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepacivirus/imunologia , Hepatite C/veterinária , Hepatite C/virologia , Hepatite C/epidemiologiaRESUMO
A total of 752 horses were involved in the CES Valencia Spring Tour 2021. Due to an equine herpesvirus-1 (EHV-1) outbreak, the competition was cancelled and the site was locked down. The objective of this study was to describe epidemiological, clinical, diagnostic, and outcome data of the 160 horses remaining in Valencia. Clinical and quantitative polymerase chain reaction (qPCR) data were analysed for 60 horses in a retrospective case-control observational study. The risk of developing clinical manifestations was explored using a logistic regression approach. EHV-1 was detected by qPCR, genotyped as A2254 (ORF30) and isolated on cell culture. From the 60 horses, 50 (83.3%) showed fever, 30 horses (50%) showed no further signs and 20 (40%) showed neurological signs, with eight horses (16%) hospitalised, of which two died (3%). Stallions and geldings were six times more likely to develop EHV-1 infection compared to mares. Horses older than 9 years, or housed in the middle of the tent were more likely to develop EHV-1 myeloencephalopathy (EHM). These data show that for EHV-1 infection, the risk factor was male sex. For EHM the risk factors were age > 9-year old and location in the middle of the tent. These data highlight the crucial role of stable design, position, and ventilation in EHV-outbreaks. It also showed that PCR testing of the horses was important to manage the quarantine.
Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Cavalos , Animais , Masculino , Feminino , Herpesvirus Equídeo 1/genética , Estudos Retrospectivos , Doenças dos Cavalos/epidemiologia , Estudos de Casos e Controles , Surtos de Doenças/veterinária , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/veterináriaRESUMO
A single-nucleotide polymorphism (A(2254) or G(2254)) in open reading frame 30 (ORF30) has been linked to the neuropathogenic phenotype of equine herpesvirus-1 (EHV-1). Identification of this polymorphism led to the development of a real-time PCR (rPCR) assay using allelic discrimination (E(2)) to distinguish between potentially neuropathogenic and nonneuropathogenic EHV-1 strains (G. P. Allen, J. Vet. Diagn. Invest. 19:69-72, 2007). Although this rPCR assay can detect and genotype EHV-1 strains, subsequent studies demonstrated that it lacks the sensitivity for the routine detection of viral nucleic acid in clinical specimens. Therefore, a new allelic discrimination EHV-1 rPCR assay (E(1)) was developed by redesigning primers and probes specific to ORF30. The E(1) and E(2) rPCR assays were evaluated using 76 archived EHV isolates and 433 clinical specimens from cases of suspected EHV-1 infection. Nucleotide sequence analysis of ORF30 was used to confirm the presence of EHV-1 and characterize the genotype (A(2254) or G(2254)) in all archived isolates plus 168 of the clinical samples. The E(1) assay was 10 times more sensitive than E(2), with a lower detection limit of 10 infectious virus particles. Furthermore, all A(2254) and G(2254) genotypes along with samples from three cases of dual infection (A(2254)+G(2254)) were correctly identified by E(1), whereas E(2) produced 20 false dual positive results with only one actual mixed A(2254)+G(2254) genotype confirmed. Based on these findings, E(1) offers greater sensitivity and accuracy for the detection and A/G(2254) genotyping of EHV-1, making this improved rPCR assay a valuable diagnostic tool for investigating outbreaks of EHV-1 infection.
Assuntos
Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/classificação , Herpesvirus Equídeo 1/isolamento & purificação , Doenças dos Cavalos/diagnóstico , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase em Tempo Real/métodos , Virologia/métodos , Animais , Erros de Diagnóstico/estatística & dados numéricos , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/virologia , Herpesvirus Equídeo 1/genética , Herpesvirus Equídeo 1/patogenicidade , Doenças dos Cavalos/virologia , Cavalos , Sensibilidade e EspecificidadeRESUMO
Equine influenza virus (EIV) is responsible for recurring outbreaks that are detrimental to the equine industry. Vaccination is key for prevention, but the effectiveness and duration of protection provided by existing vaccines is often insufficient. In order to improve vaccine efficacy, we evaluated the benefit of immune stimulation with inactivated Parapoxvirus ovis (iPPVO) on the antibody response induced by a vaccine boost against EIV. A whole inactivated ISCOMatrix-adjuvanted equine influenza vaccine was administered alone (n = 10) or combined with iPPVO injections at D0, D2 and D4 post vaccination (n = 10) to adult horses that required a vaccine boost 6 months after the last immunization, as now recommended by the WOAH. Antibody levels were measured with the single radial haemolysis (SRH) assay at 1, 3 and 6 months post-vaccination. Results revealed that horses that received iPPVO had higher antibody levels than the control group injected with the EI vaccine alone. Although the vaccine used contains only a clade 1 and European lineage strain, the increase in protective antibodies was also observed against a clade 2 strain. Thus, immune stimulation with iPPVO, a substance already marketed as an immunostimulant, could be used to improve vaccination protocols in horses and potentially other species.
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Equid alphaherpesvirus-1 (EHV-1) is one of the main pathogens in horses, responsible for respiratory diseases, ocular diseases, abortions, neonatal foal death and neurological complications such as equine herpesvirus myeloencephalopathy (EHM). Current vaccines reduce the excretion and dissemination of the virus and, therefore, the extent of an epizooty. While their efficacy against EHV-1-induced abortion in pregnant mares and the decreased occurrence of an abortion storm in the field have been reported, their potential efficacy against the neurological form of disease remains undocumented. No antiviral treatment against EHV-1 is marketed and recommended to date. This study aimed to measure the protection induced by valganciclovir (VGCV), the prodrug of ganciclovir, in Welsh mountain ponies experimentally infected with an EHV-1 ORF30-C2254 strain. Four ponies were administered VGCV immediately prior to experimental EHV-1 infection, while another four ponies received a placebo. The treatment consisted in 6.5 mg/kg body weight of valganciclovir administered orally three times the first day and twice daily for 13 days. Clinical signs of disease, virus shedding and viraemia were measured for up to 3 weeks. The severity of the cumulative clinical score was significantly reduced in the treated group when compared with the control group. Shedding of infectious EHV-1 was significantly reduced in the treated group when compared with the control group between Day + 1 (D + 1) and D + 12. Viraemia was significantly reduced in the treated group when compared with the control group. Seroconversion was measured in all the ponies included in the study, irrespective of the treatment received. Oral administration of valganciclovir induced no noticeable side effect but reduced clinical signs of disease, infectious virus shedding and viraemia in ponies experimentally infected with the EHV-1 C2254 variant.
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This study showed that under specifically defined conditions with respect to nucleic acid extraction method and testing reagents, a previously described real-time reverse transcription-PCR (rRT-PCR) assay (T1 assay) provides sensitivity equal to or higher than that of virus isolation for the detection of equine arteritis virus in semen.
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Infecções por Arterivirus/veterinária , Equartevirus/isolamento & purificação , Doenças dos Cavalos/diagnóstico , Separação Imunomagnética/métodos , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sêmen/virologia , Animais , Infecções por Arterivirus/diagnóstico , Infecções por Arterivirus/virologia , Equartevirus/genética , Doenças dos Cavalos/virologia , Cavalos , RNA Viral/genética , Sensibilidade e Especificidade , Medicina Veterinária/métodos , Virologia/métodosRESUMO
Five equine herpesvirus 1 (EHV-1) genome sequences with links to an EHV-1 outbreak with neurological disorders after a horse gathering in Valencia, Spain, in February 2021, were determined. All strains showed the closest relationships to strains from Belgium and the United Kingdom, indicating a common source of infection.
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African horse sickness virus (AHSV) is an Orbivirus within the Reoviridae family, spread by Culicoides species of midges, which infects equids with high mortality, particularly in horses and has a considerable impact on the equine industry. In order to control the disease, we previously described Entry Competent Replication Abortive (ECRA) virus strains for each of the nine distinct AHSV serotypes and demonstrated their potential as vaccines, first in type I interferon receptor (IFNAR-/-) knockout mice, and then in ponies. In this report we have investigated whether or not a combination ECRA vaccine comprising nine vaccine strains as two different cocktails is as efficient in ponies and the duration of the immunity triggered by ECRA vaccines. In one study, a group of ponies were vaccinated with a cocktail of 4 vaccine strains, followed by a vaccination of the remaining 5 vaccine strains, mimicking the current live attenuated vaccine regimen. In the second study, ponies were vaccinated with a single ECRA-AHSV strain and monitored for 6 months. The first group of ponies developed neutralising antibody responses against all 9 serotypes, indicating that no cross-serotype interference occurred, while the second group developed robust neutralising antibody responses against the single serotype that were sustained at the same level throughout a 6-month study. The results support our previous data and further validate ECRA vaccines as a safe and efficacious replacement of current live vaccines.
Assuntos
Vírus da Doença Equina Africana , Doença Equina Africana , Vacinas Virais , Doença Equina Africana/prevenção & controle , Vírus da Doença Equina Africana/genética , Animais , Cavalos , Camundongos , Sorogrupo , Vacinas AtenuadasRESUMO
Fifty-three strains belonging to the pathogenic species Leptospira interrogans and Leptospira kirschneri were analyzed by multilocus sequence analysis. The species formed two distinct branches. In the L. interrogans branch, the phylogenetic tree clustered the strains into three subgroups. Genogroups and serogroups were superimposed but not strictly.
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Técnicas de Tipagem Bacteriana/métodos , Impressões Digitais de DNA/métodos , Leptospira/classificação , Leptospira/genética , Análise de Sequência , Animais , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Genótipo , Humanos , Leptospira/isolamento & purificação , Leptospirose/microbiologia , Leptospirose/veterinária , Dados de Sequência Molecular , Filogenia , SorotipagemRESUMO
Few data on cytokine profiles in bronchoalveolar lavage fluid (BALF) are available for racehorses with mild/moderate equine asthma (EA); cytological diagnosis being most frequently made from only one lung. The purpose of the study was to compare cytokine mRNA expressions and protein concentrations in BALF from both lungs. As part of a larger study, 250 ml saline was randomly instilled in one lung and 500 ml in the contralateral lung of 30 clinically healthy Standardbred racehorses. This procedure was repeated 72 h later, inversing the volume per lung. Cytological cut-off values for diagnosis of mild EA was neutrophil proportions > 10% when instilling 250 ml. Eleven horses that exhibited unilateral mild inflammatory cytology [i.e., normal cytology (<10% neutrophils) in the other lung] were enrolled. Protein concentrations were not significantly different between lungs, for any of the investigated cytokines. Relative mRNA expression of IL-1ß (3.887 ± 0.929) and IL-10 (3.225 ± 0.516) were significantly higher in BALF from mild inflammatory lungs when compared with non-inflammatory ones (1.408 ± 0.337 and 1.488 ± 0.420, respectively); and also significantly correlated with neutrophil proportions (R = 0.45 and R = 0.58, respectively). These findings suggest that specific inflammatory response and/or regulation locally occurs within the lower airways.
RESUMO
Background: The growing interest in mesenchymal stromal cells (MSCs) in equine medicine, together with the development of MSC biobanking for allogeneic use, raises concerns about biosafety of such products. MSCs derived from umbilical cord (UC) carry an inherent risk of contamination by environmental conditions and vertical transmission of pathogens from broodmares. There is yet no report in the scientific literature about horses being contaminated by infected MSC products, and no consensus about systematic infectious screening of umbilical cord-derived mesenchymal stromal cells (UC-MSCs) to ensure microbiological safety of therapeutic products. Objectives: To develop a standard protocol to ensure UC-MSC microbiological safety and to assess the risk of vertical transmission of common intracellular pathogens from broodmares to paired UC-MSCs. Study Design and Methods: Eighty-four UC and paired peripheral maternal blood (PMB) samples were collected between 2014 and 2016. Sterility was monitored by microbiological control tests. Maternal contamination was tested by systematical PMB PCR screening for 14 pathogens and a Coggins test. In case of a PCR-positive result regarding one or several pathogen(s) in PMB, a PCR analysis for the detected pathogen(s) was then conducted on the associated UC-MSCs. Results: Ten out of 84 UC samples were contaminated upon extraction and 6/84 remained positive in primo culture. The remaining 78/84 paired PMB & UC-MSC samples were evaluated for vertical transmission; 37/78 PMB samples were PCR positive for Equid herpesvirus (EHV)-1, EHV-2, EHV-5, Theileria equi, Babesia caballi, and/or Mycoplasma spp. Hepacivirus was detected in 2/27 cases and Theiler Diseases Associated Virus in 0/27 cases (not performed on all samples due to late addition). All paired UC-MSC samples tested for the specific pathogen(s) detected in PMB were negative (37/37). Main Limitations: More data are needed regarding MSC susceptibility to most pathogens detected in PMB. Conclusions: In-process microbiological controls combined with PMB PCR screening provide a comprehensive assessment of UC-MSC exposure to infectious risk, vertical transmission risk appearing inherently low.