Senecavirus A (SVA) is a picornavirus that is endemic in swine, causing a vesicular disease clinically indistinguishable from other vesicular diseases, like foot-and-mouth disease. The widespread viral circulation, constant evolution, and economic losses caused to the swine industry emphasize the need for measures to control the agent. In this study, we evaluated the immunogenicity of a whole-virus-inactivated vaccine using a representative contemporary Brazilian SVA strain in Balb/ByJ mice. The animals were vaccinated with two doses by an intramuscular route. The humoral response induced by the vaccination was evaluated by an in-house ELISA assay for IgG detection. The cellular response was assessed by flow cytometry after in vitro SVA stimulation in splenocyte cultures from vaccinated and non-vaccinated groups. Protection against SVA was assessed in the experimental groups following an oral challenge with the homologous virus. The vaccination induced high levels of IgG antibodies and the proliferation of CD45R/B220⁺sIgM⁺, CD3e⁺CD69⁺, and CD3e⁺CD4⁺CD44⁺CD62L⁻ cells. These results indicate the immunogenicity and safety of the vaccine formulation in a murine model and the induction of humoral and cellular response against SVA.

Viruses are responsible for several diseases in animals and have also been linked to the drastic decrease in the number of bee hives worldwide. Considering the necessity to diagnose honey bee viruses, we developed and standardized two multiplex RT-PCRs. We evaluated the presence of six viruses described in Africanized Apis mellifera bees: Deformed wing virus (DWV), Sacbrood bee virus (SBV), Acute bee paralysis virus (ABPV), Israeli acute paralysis virus (IAPV), Black queen cell virus (BQCV), and Chronic bee paralysis virus (CBPV). Therefore, 164 samples of honey bees were collected in 27 apiaries of 12 municipalities in the states of Rio Grande do Sul and Santa Catarina, in southern Brazil. Among the 12 municipalities evaluated, five presented positive samples for BQCV, ABPV and DWV. Cases of co-infection by ABPV and BQCV and BQCV and DWV were observed in both states. In all apiaries with positive samples for viruses, Varroa destructor mite was reported or found. These results demonstrate the high occurrence of BQCV (36%) and the presence of ABPV (3%) and DWV (1%) in apiaries in Rio Grande do Sul, as well as in an apiary in Santa Catarina (75% BQCV and 12% DWV). The results confirm the circulation of these viruses in adult Africanized honey bees in southern Brazil, a factor that may be involved with the decline in the number of honey bees in this region of the country.

Avian poxvirus (APV) is an enveloped double-stranded DNA virus that affects many domestic and wild birds worldwide. APVs are classified into three clades (A to C), represented by fowlpox (FP) virus (clade A), canarypox virus (clade B), and psittacinepox virus (clade C), although two additional clades (D and E) have been proposed. In this study, a tumorlike skin lesion found in a domestic fowl was submitted for molecular diagnosis of Avipoxvirus by PCR and sequencing. The phylogenetic analysis revealed that the amplified segment of the corelike 4b protein and polymerase genes clustered in clade E. The APVs in clade E were previously reported from outbreaks in Hungary (flock of turkeys) and in Mozambique (layer chickens), associated with a possible vaccine failure to protect against clade E viruses. To our knowledge, this report is the first identification of clade E in this country, providing new information about host range and genetic diversity of APVs in Brazil, and may represent a potential risk of FP disease outbreaks in commercial poultry.

Os objetivos deste trabalho foram estudar a epidemiologia e a distribuição das lesões de sarcoide equino diagnosticado no Laboratório Regional de Diagnóstico da UFPel (LRD/UFPel) em um período de 20 anos, bem como determinar os principais tipos e, por meio da PCR, identificar o papilomavirus bovino (BPV) envolvido nas lesões. Os casos recebidos entre 2000 e 2020 foram resgatados dos protocolos de necropsia do laboratório. Os blocos parafinados de cada caso foram cortados em secções de 3-5µm, corados por hematoxilina e eosina (HE) e reavaliados em microscópio ótico. As amostras encaminhadas ao laboratório em 2021 foram fixadas em formalina 10% para histopatologia e imuno-histoquímica e parte, foi congelada e encaminhada ao Laboratório de Virologia e Imunologia da UFPel (LabVir/UFPel) para realização da PCR. No período foram diagnosticados 258 casos, dos quais 75,96% na raça Crioula principalmente em equinos de dois a cinco anos (42,64%). As características macroscópicas associadas à histopatologia permitiram determinar o tipo de sarcoide em cada caso. Em 46,8% dos casos os sarcoides eram fibroblásticos. Dos 258 casos 61% eram únicos, observados principalmente nos membros e 32% eram múltiplos, presentes com mais frequência do tronco. O genoma dos BPVs não foi detectado pela PCR e a IHQ foi negativa para proteína S-100 e positiva para vimentina permitindo o diagnóstico diferencial de outras neoplasias cutâneas dos equinos. O registro de 258 casos de sarcoide em 20 anos permitiu estabelecer a sua epidemiologia na região Sul do Rio Grande do Sul e alerta para a importância da doença na região. The objective of this work was to study the epidemiology and distribution of equine sarcoid lesions diagnosed at the Laboratório Regional de Diagnóstico of UFPel (LRD/UFPel) over a period of 20 years, as well as to determine the main types and, the molecular identify of the bovine papillomavirus (BPV) associated to the lesions. Cases received between 2000 and 2020 were retrieved from the laboratory's necropsy protocols. The paraffin blocks of each case were cut into 3-5µm sections, stained with hematoxylin and eosin (HE) and reassessed under an optical microscope. The samples sent to the laboratory in 2021 were fixed in 10% formalin for histopathology and immunohistochemistry and, an aliquot of frozen tissues were sent to the Laboratory of Virology and Immunology (LabVir/UFPel) for PCR. During the study period, 258 cases were diagnosed, of which 75.96% in the Crioula breed, mainly in horses aged two to five years (42.64%). The macroscopic characteristics associated with the histopathology allowed us to determine the type of sarcoid in each case. In 46.8% of the cases, the sarcoids were fibroblastic. Of the 258 cases, 61% were single, mainly observed in the limbs, and 32% were multiple, most often present in the trunk. The BPV genome was not detected by PCR and the IHC was negative for protein S-100 and positive for vimentin, allowing the differential diagnosis of other equine cutaneous neoplasms. The record of 258 cases of equine sarcoid for approximately 20 years has contributed significantly to understand its epidemiology in southern Rio Grande do Sul and revealed the importance of the disease in the studied region. Los objetivos de este trabajo fueron estudiar la epidemiología y distribución de las lesiones de sarcoidosis equina diagnosticadas en el Laboratorio Regional de Diagnóstico de la UFPel (LRD/UFPel) en un período de 20 años, así como determinar los principales tipos y, mediante PCR, identificar el virus del papiloma bovino (BPV) implicado en las lesiones. Los casos recibidos entre 2000 y 2020 se recuperaron de los protocolos de necropsia del laboratorio. Los bloques de parafina de cada caso se cortaron en secciones de 3-5 µm, se tiñeron con hematoxilina y eosina (HE) y se reevaluaron al microscopio óptico. Las muestras enviadas al laboratorio en 2021 fueron fijadas en formol al 10% para histopatología e inmunohistoquímica y parte fue congelada y enviada al Laboratorio de Virología e Inmunología de la UFPel (LabVir/UFPel) para PCR. En el período fueron diagnosticados 258 casos, de los cuales el 75,96% en la raza Crioula, principalmente en equinos de dos a cinco años (42,64%). Las características macroscópicas asociadas a la histopatología permitieron determinar el tipo de sarcoide en cada caso. En el 46,8% de los casos las sarcoides eran fibroblásticas. De los 258 casos, el 61% fueron únicos, principalmente observados en las extremidades, y el 32% fueron múltiples, con mayor frecuencia presentes en el tronco. El genoma del BPV no fue detectado por PCR y la IHC fue negativa para proteína S-100 y positiva para vimentina, lo que permitió el diagnóstico diferencial de otras neoplasias cutáneas equinas. El registro de 258 casos de sarcoide en 20 años permitió establecer su epidemiología en la región sur de Rio Grande do Sul y alerta sobre la importancia de la enfermedad en la región.

Senecavirus A (SVA) is a picornavirus that was first isolated in the USA in 2002; however, there is evidence that the virus was circulating in swine herds since 1988. Despite frequent reports of vesicular disease outbreaks caused by SVA infection in swine in Brazil since 2014, there is limited data on the genetic diversity and evolution of the virus in the country. SVA was isolated from swine exhibiting vesicular lesions, with samples originating from farms or slaughterhouses across 57 municipalities in 8 Brazilian states between 2018 and 2022. We obtained 501 SVA genomes through Sanger and Oxford Nanopore sequencing. Phylogenetic analysis revealed that Brazilian SVA sequences are genetically distinct from sequences from other countries, including China, USA and Canada, and form a monophyletic cluster, indicating a common ancestor for the viruses currently circulating in Brazil. Furthermore, there are two main clusters with sequences from the Midwest and Southern regions, suggesting that SVA is evolving independently in the swine population of the country. Pairwise sequence comparisons allowed us to identify seven unique mutations with high frequency in the Brazilian SVA sequences. Notably, mutations were identified in specific regions of the capsid proteins that interact with the host cell receptor (ANTRX1) and in surface-exposed residues, suggesting potential evolutionary changes due to receptor interaction or immune pressure. Recombination analysis provided evidence of at least five recombination events among the Brazilian strains. These findings offer new insights into the evolution of SVA circulating in Brazil and into the global epidemiology/evolutionary dynamics of the virus.

O sistema imune presente nas mucosas representa a barreira inicial frente à infecção por diversos patógenos que utilizam estas superfícies como porta de entrada no organismo hospedeiro, como é o caso dos Alphaherpesvirus bovino 1 (BoHV-1) e Alphaherpesvirus bovino 5 (BoHV-5). Estes vírus infectam os sistemas reprodutivo e respiratório de bovinos e são responsáveis por casos de Rinotraqueíte Infecciosa Bovina, Vulvovaginite Pustular Infecciosa e Balanopostite Pustular Infecciosa, assim como Meningoencefalite Herpética Bovina, respectivamente. A infecção pelos BoHVs ocorre nas cavidades revestidas por células epiteliais de mucosa, principalmente nasal e genital, sendo o ponto inicial de replicação, seguindo-se a disseminação local, viremia eventual e disseminação neuronal, até o estabelecimento da latência. A cooperação dos mecanismos de defesa confere proteção através do sistema integrado de mucosas por meio da ativação dos sítios efetores e especialmente produção de diferentes isotipos de imunoglobulinas, como a SIgA, realiza neutralização nas superfícies mucosas, e a IgG, que desempenha neutralização na mucosa e sistemicamente. A indução da imunidade nas superfícies mucosas através do uso de vacinas torna-se de extrema importância para a prevenção da adsorção do vírus à célula e infecção pelos microrganismos patogênicos e depende, especialmente, do imunógeno, via de imunização e substância adjuvante empregada nas formulações. Esta revisão teve como objetivo abordar os principais aspectos relacionados à infecção pelo BoHV-1 e BoHV-5, assim como os tipos de resposta relacionadas ao sistema imune de mucosas frente a estes vírus e, ainda, estudos relacionados à utilização das vias mucosas para administração de vacinas em diferentes espécies animais.