Canine distemper virus (CDV), currently termed Canine morbillivirus, is an extremely contagious disease that affects dogs. It is identified as a multiple cell tropism pathogen, and its host range includes a vast array of species. As a member of Mononegavirales, CDV has a negative, single-stranded RNA genome, which encodes eight proteins. Regarding the molecular pathogenesis, the hemagglutinin protein (H) plays a crucial role both in the antigenic recognition and the viral interaction with SLAM and nectin-4, the host cells’ receptors. These cellular receptors have been studied widely as CDV receptors in vitro in different cellular models. The SLAM receptor is located in lymphoid cells; therefore, the infection of these cells by CDV leads to immunosuppression, the severity of which can lead to variability in the clinical disease with the potential of secondary bacterial infection, up to and including the development of neurological signs in its later stage. Improving the understanding of the CDV molecules implicated in the determination of infection, especially the H protein, can help to enhance the biochemical comprehension of the difference between a wide range of CDV variants, their tropism, and different steps in viral infection. The regions of interaction between the viral proteins and the identified host cell receptors have been elucidated to facilitate this understanding. Hence, this review describes the significant molecular and cellular characteristics of CDV that contribute to viral pathogenesis.

Morbilliviruses share considerable structural and functional similarities. Even though disease severity varies among the respective host species, the underlying pathogenesis and the clinical signs are comparable. Thus, insights gained with one morbillivirus often apply to the other members of the genus. Since the Canine distemper virus (CDV) causes severe and often lethal disease in dogs and ferrets, it is an attractive model to characterize morbillivirus pathogenesis mechanisms and to evaluate the efficacy of new prophylactic and therapeutic approaches. This review compares the cellular tropism, pathogenesis, mechanisms of persistence and immunosuppression of the Measles virus (MeV) and CDV. It then summarizes the contributions made by studies on the CDV in dogs and ferrets to our understanding of MeV pathogenesis and to vaccine and drugs development.

Bats are mammals with high biodiversity and wide geographical range. In Brazil, three haematophagous bat species are found. Desmodus rotundus is the most documented due to its role as a primary host of rabies virus in Latin America. Bats are known to harbor various emerging viruses causing severe human diseases. Beyond zoonotic viruses, these animals also harbor a diversity of non-zoonotic viruses. Papillomaviruses are circular double-stranded deoxyribonucleic acid (dsDNA) viruses that infect the epithelial and mucosal cells of many vertebrates, occasionally causing malignant lesions. High-throughput sequencing has enabled papillomaviruses discovery in different bat species. Here, 22 D. rotundus samples were collected through the rabies eradication program in Rio Grande do Sul. The DNA extracted from pooled intestines was amplified by the rolling-circle amplification (RCA) method and sequenced using the Illumina^® MiSeq platform (San Diego, CA, USA).Analysis revealed three contigs corresponding to the Papillomaviridae family, representing three novel viruses named DrPV-1, DrPV-2, and DrPV-3. Phylogenetic analysis suggests DrPV-1 may constitute a new species within the Dyophipapillomavirus genus, while DrPV-2 and DrPV-3 may represent different types within the same species from a novel genus. This is the first description of a papillomavirus in the D. rotundus species, contributing to the characterization of PVs in the Chiropteran order.

The conjunctiva plays an essential role in eye health and immunity and acts as a barrier to the entry of microorganisms. Conjunctival infections are common in dogs and result from both the invasion of pathogenic microorganisms and the uncontrolled growth of the existing microbiota. Most of the existing data come from studies based on traditional culture methods. These reports indicate the predominance of gram-positive bacteria, especially Staphylococcus spp. In the present study, we analyzed the microbiota present on the conjunctival surface from a heterogeneous dog population without ophthalmological disorders using DNA sequencing. After a thorough ophthalmological examination, conjunctival swabs were collected from both eyes of 30 dogs. After processing and nucleic acid extraction, the sample pool was subjected to shotgun DNA sequencing through the Illumina platform and analyzed via the Metagenomic Rapid Annotations using Subsystems Technology (MGRAST) server. A predominance of the phylum Proteobacteria and the genera Ralstonia and Burkholderia were identified along with a minority of fungi, whereas viruses were not found. Microbial DNA sequencing has provided new data on this subject, revealing the presence of noncultivable organisms that were previously unknown as part of the ocular microbiome.

A conjuntiva desempenha papel fundamental na saúde e imunidade ocular e atua como uma barreira à entrada de microrganismos. As infecções conjuntivais são comuns em cães e resultam tanto da invasão de microrganismos patogênicos quanto do crescimento descontrolado da microbiota existente. A maior parte dos dados existentes provém de estudos baseados em métodos de cultura tradicionais. Esses relatos apontam para o predomínio de bactérias gram-positivas, principalmente Staphylococcus spp. O presente estudo analisou a comunidade microbiana presente na conjuntiva ocular de uma população heterogênea de cães sem distúrbios oftalmológicos por sequenciamento de DNA. Após exame oftálmico minucioso, foram coletados suabe conjuntivais de ambos os olhos de 30 cães. Após processamento e extração de ácidos nucleicos, o pool de amostras foi submetido ao sequenciamento shotgun de DNA por meio da plataforma Illumina e analisado no servidor Metagenomic Rapid Annotations using Subsystems Technology (MG-RAST). Foi identificada uma predominância do filo Proteobacteria e dos gêneros Ralstonia e Burkholderia juntamente com uma minoria de fungos, enquanto vírus não foram encontrados. O sequenciamento do DNA microbiano trouxe novos dados sobre o assunto, revelando a presença de organismos não cultiváveis até então desconhecidos como parte do microbioma ocular.