182 research outputs found
Replication of Influenza D Viruses of Bovine and Swine Origin in Ovine Respiratory Explants and Their Attachment to the Respiratory Tract of Bovine, Sheep, Goat, Horse, and Swine
No full textBovine is considered the main reservoir of influenza D virus (IDV), however, low levels of seropositivity in other farmed species suggest a wide range of potential hosts. Nevertheless, it is not clear whether this scenario is the result of rare spillover events upon contact with bovines, or a lack of adaptation of IDV to these hosts. Among these species, sheep represents a crucial component of the rural economy in many developing countries, but little is known about its role in the ecology of the disease. To evaluate the susceptibility of sheep to IDV viruses of different origin, we used ovine respiratory tissues as an ex vivo model and investigated the infective phenotype of two IDV strains isolated from either bovine (IDV-BOV) or swine (IDV-SW). For translatability purposes, we included a parainfluenza type 3 virus, as positive control, given its known respiratory tropism in sheep. We performed a timed evaluation of the viral infectivity, cell tropism and the associated histopathology, by means of tissue culture infectious dose assays on supernatants and histological/immunohistochemical analyses on explanted tissues, respectively. To further investigate differences in the phenotype of these two strains and to identify the potential targets of replication in the most commonly land-based farmed mammalian species, we carried out virus binding assays on histological sections of the respiratory tract of bovine, caprine, ovine, horse and swine. Our results demonstrated that IDV successfully replicates in nasal, tracheal and lung ovine tissues, suggesting a moderate susceptibility of this species to IDV infection. Interestingly, despite the high genetic identity of these strains, IDV- BOV consistently replicated to higher titers than IDV-SW in all respiratory tracts, suggesting IDV viruses might display considerable levels of variability in their phenotype when crossing the species barrier. Virus binding assays confirmed a superior affinity of the IDV viruses for the bovine upper respiratory tract, and a preference for the pharyngeal epithelium of small ruminants, indicating possible targets to improve the sensitivity of virological sampling for diagnostic and post-mortem purposes. Further pathogenesis and cross-species transmission studies will be necessary to elucidate the ecology of IDV and eventually allow the design of cost-effective surveillance strategies
Surveillance of Hepatitis E virus (HEV) in swine farms and farmers and first identification of genotype 4 in Italy.
No full textAbstract
Hepatitis E is an emerging zoonotic disease caused by a positive ssRNA
virus, Hepatitis E virus (HEV). In Europe, pigs are the main reservoir.
Genotype 3 of HEV (HEV3) has a worldwide distribution while genotype 4
(HEV4) mostly occurs in Asia. However, HEV4 has recently been isolated
in pigs and humans in Europe.
Abstract methods
During 2011-2014, a monitoring plan was performed to evaluate the
prevalence of HEV infection in different human populations and pigs in
Italy. Assuming an expected herd-level seroprevalence of 50%, 175 pig
farms were sampled. To detect at least one positive sample assuming a
within-herd seroprevalence of 30%, 9 sera were collected and analyzed
from each farm. Moreover, in 105 farms HEV presence was investigated
collecting 10 fecal pools. In order to understand whether consumption
of pork products or/and contact with pigs may represent a risk factor,
sera were collected from farmers (no.127), general population(no.131)
and vegetarian/vegan group (no.114).
Abstract results
Anti-HEV antibodies were detected in 65.7% (115/175,95% CI:58.2-72.7)
of farms, while viral RNA was identified in 24.8% (26/105). Most of the
identified strains belonged to HEV3. However, in one farm HEV4 was
detected. HEV seroprevalence in humans was significantly different
among the 3 groups (p<0.001): farmers showing the greatest prevalence
(15.75%,95% CI:9.9-23.3) and general population the lowest (2.3%,95%
CI:0.5-6.5). No significant differences were found between general
population (omnivorous) and vegetarian/vegan group.
Abstract conclusion
The survey confirmed a wide spread of HEV in Italian pig herds. The
finding of HEV4 can be an issue of concern, considering that it may
cause a more severe clinical course in humans. Moreover, our findings
reinforce the opinion that HEV infection in industrial countries could be
associated with professional activity
Detection of avian influenza virus: a comparative study of the in silico and in vitro performances of current RT-qPCR assays
No full textIdentification of two divergent swine Noroviruses detected at the slaughterhouse in North East Italy
No full textFirst report outside Eastern Europe of West Nile virus lineage 2 related to the Volgograd 2007 strain, northeastern Italy, 2014
No full textWest Nile virus (WNV) is a Flavivirus transmitted to vertebrate hosts by mosquitoes, maintained in nature through an enzootic bird-mosquito cycle. In Europe the virus became of major public health and veterinary concern in the 1990s. In Italy, WNV re-emerged in 2008, ten years after the previous outbreak and is currently endemic in many areas of the country. In particular, the northeastern part of Italy experience continuous viral circulation, with human outbreaks caused by different genovariants of WNV lineage 1, Western-European and Mediterranean subcluster, and WNV lineage 2, Hungarian clade. Alongside the WNV National Surveillance Program that has been in place since 2002, regional surveillance plans were implemented after 2008 targeting mosquitoes, animals and humans
SARS-CoV-2 intra-host evolution during prolonged infection in an immunocompromised patient
No full textObjectives: Intra-host SARS-CoV-2 evolution during chronic infection in immunocompromised hosts has been suggested as being the possible trigger of the emergence of new variants. Methods: Using a deep sequencing approach, we investigated the SARS-CoV-2 intra-host genetic evolution in a patient with HIV over a period of 109 days. Results: Sequencing of nasopharyngeal swabs at three time points demonstrated dynamic changes in the viral population, with the emergence of 26 amino acid mutations and two deletions, 57% of them in the Spike protein. Such a combination of mutations has never been observed in other SARS-CoV-2 lineages detected so far. Conclusion: Our data confirm that persistent infection in certain immunocompromised individuals for a long time may favor the dangerous emergence of new SARS-CoV-2 variants with immune evasion properties
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