An outbreak of neonatal enteritis in buffalo calves associated with astrovirus

Background: Enteritis of an infectious origin is a major cause of productivity and economic losses to cattle producers worldwide. Several pathogens are believed to cause or contribute to the development of calf diarrhea. Astroviruses (AstVs) are neglected enteric pathogens in ruminants, but they have recently gained attention because of their possible association with encephalitis in humans and various animal species, including cattle. Objectives: This paper describes a large outbreak of neonatal diarrhea in buffalo calves (Bubalus bubalis), characterized by high mortality, which was associated with an AstV infection. Methods: Following an enteritis outbreak characterized by high morbidity (100%) and mortality (46.2%) in a herd of Mediterranean buffaloes (B. bubalis) in Italy, 16 samples from buffalo calves were tested with the molecular tools for common and uncommon enteric pathogens, including AstV, kobuvirus, and torovirus. Results: The samples tested negative for common enteric viral agents, including Rotavirus A, coronavirus, calicivirus, pestivirus, kobuvirus, and torovirus, while they tested positive for AstV. Overall, 62.5% (10/16) of the samples were positive in a single round reverse transcription polymerase chain reaction (PCR) assay for AstV, and 100% (16/16) were positive when nested PCR was performed. The strains identified in the outbreak showed a clonal origin and shared the closest genetic relationship with bovine AstVs (up to 85% amino acid identity in the capsid). Conclusions: This report indicates that AstVs should be included in a differential diagnosis of infectious diarrhea in buffalo calves

Molecular detection of canine bufaviruses in wild canids

Novel protoparvoviruses genetically related to human and non-human primate bufaviruses (BuVs) have been detected recently in respiratory and enteric specimens collected from dogs and cats. In this study, by molecular screening of archival collections of faecal samples from wolves and foxes, we detected BuVs with a rate of 17.1% (7/41) and 10.5% (9/86), respectively. Sequence analysis of a portion of the ORF2 gene region of nine positive samples showed that the viruses in these samples were closely related to BuVs (97.5–99.0% nucleotide sequence identity) found in domestic carnivores

Genome sequence of an aichivirus detected in a common pipistrelle bat (Pipistrellus pipistrellus)

The family Picornaviridae includes important human and animal pathogens that are associated with a wide range of diseases and, in some cases, have zoonotic potential. During epidemiological surveillance of bats, we identified, by next-generation sequencing (NGS) techniques, the presence of picornavirus RNA in a common pipistrelle bat (Pipistrellus pipistrellus). By coupling NGS, primer-walking strategies, and sequence-independent protocols to obtain the sequences of the 5′ and 3′ termini, we reconstructed the genome sequence of picornavirus strain ITA/2017/189/18-155. The genome of the bat picornavirus is 8.2 kb in length and encodes a polyprotein of 2462 amino acids. A comparison of polyprotein sequences revealed that this virus is distantly related (65.1% and 70.9% sequence identity at the nucleotide and amino acid level, respectively) to a bat aichivirus identified in 2010. Phylogenetic analysis showed that this picornavirus clustered closely with members of the genus Kobuvirus, which also includes human and animal aichiviruses. The identification of aichiviruses in several animal hosts is providing hints that will lead to an understanding of their origin and evolutionary patterns

Analysis of oral microbiota in non-vital teeth and clinically intact external surface from patients with severe periodontitis using Nanopore sequencing: a case study

Periodontal diseases include a wide range of pathological conditions, damaging the supporting structures of the teeth. Origin and propagation of periodontal disease is believed to be caused by dysbiosis of the commensal oral microbiota. The aim of this study was to evaluate the presence of bacteria in the pulp cavity of teeth with severe periodontal disease with clinically intact external surface. Periodontal (P) and endodontic (E) tissue samples of root canals from six intact teeth of three patients were sampled for analysis of microbial population using Nanopore technology. Streptococcus was the predominant genus in E samples. Porphyromonas (33.4%, p = 0.047), Tannerella (41.7%, p = 0.042), and Treponema (50.0%, p = 0.0064) were significantly more present in P than in E samples. Some samples (E6 and E1) exhibited a remarkable difference in terms of microbial composition, whilst Streptococcus was a common signature in samples E2 to E5, all which were obtained from the same patient. In conclusion, bacteria were identified on both the root surface and the root canal system, thus demonstrating the possibility of bacteria to spread directly from the periodontal pocket to the root canal system even in the absence of crown’s loss of integrity

Assessing the virucidal activity of essential oils against feline calicivirus, a non-enveloped virus used as surrogate of norovirus

Norovirus (NoV) causes serious gastrointestinal disease worldwide and is regarded as an important foodborne pathogen. Due the difficulties of in vitro cultivation for human NoV, alternative caliciviruses (i.e., feline calicivirus, FCV, or murine NoV) have long been used as surrogates for in vitro assessment of the efficacy of antivirals. Essential oils (EOs) are natural compounds that have displayed antimicrobial and antioxidant properties. We report in vitro the virucidal efficacy of four EOs, Melissa officinalis L. EO (MEO), Thymus vulgaris L. EO (TEO), Rosmarinus officinalis L. EO (REO), and Salvia officinalis L. EO (SEO) against FCV at different time contacts (10, 30 min, 1, 4 and 8 h). At the maximum non-cytotoxic concentration and at 10- and 100- fold concentrations over the cytotoxic threshold, the EOs did not decrease significantly FCV viral titers. However, MEO at 12,302.70 μg/mL exhibited a significant efficacy decreasing the viral titer by 0.75 log10 Tissue Culture Infectious Dose (TCID50)/50 μl after 10 min as compared to virus control. In this study, virucidal activity of four EOs against FCV, was investigated. A lack of virucidal efficacy of TEO, REO and SEO at different compound concentrations and time contacts against FCV was observed whilst MEO was able to significantly decrease FCV titer

Detection of antibodies against domestic cat hepadnavirus using baculovirus-expressed core protein

A novel orthohepadnavirus (domestic cat hepadnavirus [DCH]) similar to human hepatitis B virus has been recently detected in serum and liver samples from domestic cats with chronic hepatitis and hepatocellular carcinoma. Molecular investigations by independent research groups around the world have revealed positivity rates ranging from 6.5% to 12.5% in blood samples and up to 14.0% in liver tissue. In this study, we screened an age-stratified collection of feline sera (n = 256) by using an antibody detection enzyme-linked immunosorbent assay based on the recombinant core antigen of DCH (DCHc). Specific antibodies (DCHc Abs) were detected with a prevalence of 25.0%. The DNA of DCH was detected in 35.9% (23/64) of seropositive cats and only in 1.0% (2/192) of seronegative animals. Based on the serological (IgG and IgM anti-DCHc) and virological status, the possible stages of DCH infection were predicted

Identification of astroviruses in bovine and buffalo calves with enteritis

Astroviruses (AstVs) have been identified in the stools of calves with enteritis and in the brain tissues of bovines with encephalitis but their pathogenic role has not been clarified. In this study, we report the detection and characterization of bovine and water buffalo AstV strains identified in young bovine and buffalo calves with enteritis in Italy between 2012 and 2015. By negative staining transmission electron microscopy (TEM) observation, AstV-like particles were identified in the stools of the animals and AstV RNA was confirmed molecularly. The sequence (~3.2-kb) at the 3′ end of the genome was determined for two bovine and two buffalo AstVs. Sequence and phylogenetic analysis on the partial ORF1b and full-length ORF2 revealed a marked genetic diversity although the viruses were distantly related to other AstV identified from ruminants. Gathering sequence information on ruminant AstVs is important to understand the extent of inter-species circulation and for the development of reliable, specific diagnostic tools

Surveillance for adenoviruses in bats in Italy

Adenoviruses are important pathogens of humans and animals. Bats have been recognized as potential reservoirs of novel viruses, with some viruses being regarded as a possible zoonotic threat to humans. In this study, we report the detection and analysis of adenoviruses from different bat species in northern Italy. Upon sequence and phylogenetic analysis, based on a short diagnostic fragment of the highly-conserved DNA polymerase gene, we identified potential novel candidate adenovirus species, including an avian-like adenovirus strain. An adenovirus isolate was obtained in simian cell lines from the carcass of a Pipistrellus kuhlii, and the complete genome sequence was reconstructed using deep sequencing technologies. The virus displayed high nucleotide identity and virtually the same genome organization as the Pipistrellus pipistrellus strain PPV1, isolated in Germany in 2007. Gathering data on epidemiology and the genetic diversity of bat adenoviruses may be helpful to better understand their evolution in the mammalian and avian hosts

Identification of hepadnavirus in the sera of cats

Hepadnaviruses infect several animal species. The prototype species, human hepatitis B virus (HBV), increases the risk of liver diseases and may cause cirrhosis and hepatocellular carcinoma. Recently a novel hepadnavirus, similar to HBV, has been identified through transcriptomics studies in a domestic cat with large cell lymphoma in Australia. Herewith, a collection of 390 feline serum samples was screened for hepadnavirus. Overall, the virus was identified in 10.8% of the sera with a significantly higher prevalence (17.8%) in the sera of animals with a clinical suspect of infectious disease. Upon genome sequencing, the virus was closely related (97.0% nt identity) to the prototype Australian feline virus Sydney 2016. The mean and median values of hepadnavirus in the feline sera were 1.3 x 10(6) and 2.1 x 10(4) genome copies per mL (range 3.3 x 10(0)-2.5 x 10(7) genome copies per mL). For a subset of hepadnavirus-positive samples, information on the hemato-chemical parameters was available and in 10/20 animals a profile suggestive of liver damage was present. Also, in 7/10 animals with suspected hepatic disease, virus load was > 104 genome copies per mL, i. e. above the threshold considered at risk of active hepatitis and liver damage for HBV