No abstract

Bats play a significant role in maintaining their ecosystems through pollination, dispersal of seeds, and control of insect populations, but they are also known to host many microorganisms and have been described as natural reservoirs for viruses with zoonotic potential. The diversity of viruses in these animals remains largely unknown, however, because studies are limited by species, location, virus target, or sample type. Therefore, the aim of this study was to detect fragments of viral genomes in bat samples. We performed high-throughput sequencing analysis and specific PCR and RT-PCR on pools of anal and oropharyngeal swabs from Artibeus lituratus and Sturnira lilium collected in southern Brazil. As a result, a member of the family Adenoviridae related to human adenovirus C was detected in anal swabs from S. lilium. In addition, we detected a papillomavirus in an anal swab from A. lituratus. Our analyses also allowed the detection of adenoviruses and parvoviruses in oropharyngeal swabs collected from A. lituratus. These results increase our knowledge about viral diversity and illustrate the importance of conducting virus surveillance in bats.

Bufotenine, an alkaloid that can be found in plant extracts and skin secretions of amphibians, is reported to have potential antiviral activity. The present study evaluated the antiviral activity of bufotenine against different genetic lineages of rabies virus (RABV, a single-stranded, negative-sense RNA virus), canine coronavirus (CCoV, a positive-sense RNA virus) and two double-stranded DNA viruses (two strains of herpes simplex virus type 1/HSV-1 [KOS and the acyclovir-resistant HSV-1 strain 29R] and canine adenovirus 2, CAV-2). The maximal non-toxic bufotenine concentrations in Vero and BHK-21 cells were determined by MTT assays. The antiviral activity of bufotenine against each virus was assessed by examination of reductions in infectious virus titres and plaque assays. All experiments were performed with and without bufotenine, and the results were compared. Bufotenine demonstrated significant RABV inhibitory activity. No antiviral action was observed against CCoV, CAV-2 or HSV-1. These findings indicate that the antiviral activity of bufotenine is somewhat linked to the particular infectious dose used and the genetic lineage of the virus, although the mechanisms of its effects remain undetermined.

This study aimed to evaluate, by molecular methods, the presence of influenza A virus (IAV) and coronavirus in non-hematophagous bats collected in the state of São Paulo, Brazil. Samples of lung tissue and small intestine from 105 bats belonging to three families ( Phyllostomidae , Vespertilionidae , and Molossidae ) were collected in 22 municipalities in the state of São Paulo. Genetic identification of bats species was performed by amplification and sequencing of a fragment of 710 bp of the mitochondrial COI gene. In the detection of IAV, genomes were performed by RT-PCR, aiming at the amplification of a 245-bp fragment of the IAV matrix (M) protein gene. For coronaviruses, two fragments of 602 and 440 bp corresponding to segments along the gene encoding the RNA-dependent RNA polymerase (RdRp) were targeted. The detection limit for each of the PCRs was also determined. All samples analyzed here were negative for both viruses, and the lower limit of detection of the PCRs for the amplification of influenza virus A and coronavirus was estimated at 3.5 × 10 3 and 4.59 genomic copies per microliter, respectively. Although bats have been shown to harbor a large number of pathogens, the results of the present study support the theory that virus circulation in bats in the wild often occurs at low viral loads and that our understanding of the complex infectious dynamics of these viruses in wild conditions is still limited.

No abstract

Os morcegos são mamíferos de grande diversidade, amplamente distribuídos no mundo. Apesar da importância desses animais na manutenção dos ecossistemas, estes também representam uma preocupação na saúde pública, uma vez que atuam como reservatórios ou hospedeiros de diferentes patógenos, principalmente vírus. A identificação das espécies de morcegos é essencial para melhor compreensão da origem e da epidemiologia de diversas doenças. Além disso, o entendimento sobre a interação vírus/hospedeiro e o papel dos morcegos na disseminação das doenças é essencial para a manutenção da diversidade e consequente conservação desses animais, permitindo assim, o controle racional dos patógenos albergados por estes. Desta forma, é imprescindível realizar a identificação correta das espécies de morcegos recebidas nos laboratórios, a fim de implantar medidas adequadas de vigilância. Neste sentido, este estudo teve como objetivo identificar geneticamente as espécies de morcegos enviados para diagnóstico de raiva no Instituto Pasteur através do sequenciamento genético parcial do gene citocromo C oxidase subunidade I (COI). Para este estudo foram selecionadas 127 amostras de pulmão de morcegos negativos para raiva obtidos em 2015. As amostras foram submetidas a extração de DNA e PCR tendo como alvo o COI e sequenciamento genético. Como resultado, foram identificadas oito espécies: Artibeus lituratus, Cynomops planirostris, Eumops glaucinus, Glossophaga soricina, Lasiurus ega, Molossus molossus, Molossus rufus e Myotis riparius, distribuídas em três famílias (Phyllostomidae, Molossidae e Vespertilionidae) comumente encontradas no Brasil. O sequenciamento parcial do gene COI foi eficaz na identificação das espécies de quirópteros podendo ser uma ferramenta auxiliar na identificação morfológica e facilmente implantada em laboratórios de biologia molecular.