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Franchin, E.

Publications and source records attributed to Franchin, E..

3 recordsLinked to original sources

First detection and characterization of Alongshan virus in Ixodes ricinus ticks from Italy, 2021-2022

Alongshan virus (ALSV) is an emerging tick-borne segmented RNA virus belonging to the Jingmenvirus group and has been reported in humans, ticks, and vertebrates across Asia and Europe. Despite its potential public health relevance, its distribution and genetic diversity remain poorly characterized in several European regions where tick-borne pathogens are endemic. In this study, we developed a specific TaqMan-based real-time RT-PCR assay targeting a conserved region of ALSV segment 2 and used it to investigate the presence of ALSV RNA in Ixodes ricinus ticks collected in northeastern Italy. The assay showed high linearity over a broad dynamic range and no cross-reactivity with related flaviviruses. A total of 212 archival tick samples collected between March 2021 and November 2022 were screened, and 28 samples (13.2%) tested positive for ALSV RNA. Positive ticks were detected in the provinces of Belluno and Vicenza and included individual adult males and nymph pools. A subset of positive samples was further characterized by nested PCR and Sanger sequencing of all four genomic segments. Phylogenetic analyses showed that Italian ALSV sequences clustered within the broader European ALSV diversity and were closely related to strains from Central and Northern Europe, without forming a distinct country-specific lineage. Sequence comparisons suggested purifying selection and revealed differences in predicted structural proteins between European and Chinese strains. These findings provide the first molecular evidence of ALSV circulation in Italy and support further studies to clarify its epidemiology, host range, genetic diversity, and potential clinical relevance. IMPORTANCEAlongshan virus (ALSV) is an emerging tick-borne virus identified in febrile patients in China and subsequently detected in ticks in Russian Federation and several European countries. Although severe disease has not yet been reported in humans, surveillance and elucidation of the virus distribution are essential to assess its pathogenicity and potential public health impact. We developed a specific real-time RT-PCR protocol and detected ALSV in Ixodes ricinus ticks collected in northeastern Italy. Sequence analyses suggested multiple introductions and revealed differences in structural proteins between European and Chinese strains, suggesting potential adaptation and differences in pathogenicity. Since the clinical signs of ALSV infection in humans may overlap with those of tick-borne encephalitis (TBE), differential diagnostic procedures should be developed to improve patient management, particularly in TBE-endemic regions such as northeastern of Italy.

microbiology↗

Rapid longitudinal SARS-CoV-2 intra-host emergence of novel haplotypes regardless of immune deficiencies

On February 2020, the municipality of Vo, a small town near Padua (Italy), was quarantined due to the first coronavirus disease 19 (COVID-19)-related death detected in Italy. The entire population was swab tested in two sequential surveys. Here we report the analysis of the viral genomes, which revealed that the unique ancestor haplotype introduced in Vo belongs to lineage B and, more specifically, to the subtype found at the end of January 2020 in two Chinese tourists visiting Rome and other Italian cities, carrying mutations G11083T and G26144T. The sequences, obtained for 87 samples, allowed us to investigate viral evolution while being transmitted within and across households and the effectiveness of the non-pharmaceutical interventions implemented in Vo. We report, for the first time, evidence that novel viral haplotypes can naturally arise intra-host within an interval as short as two weeks, in approximately 30% of the infected individuals, regardless of symptoms severity or immune system deficiencies. Moreover, both phylogenetic and minimum spanning network analyses converge on the hypothesis that the viral sequences evolved from a unique common ancestor haplotype, carried by an index case. The lockdown extinguished both viral spread and the emergence of new variants, confirming the efficiency of this containment strategy. The information gathered from household was used to reconstructs possible transmission events. AUTHOR SUMMARYIt is of great interest and importance to understand SARS-CoV-2 ability to mutate generating new viral strains, and to assess the impact of containment strategies on viral transmission. In this study we highlight the rapid intra-host haplotype evolution regardless of symptom severity and immune deficiencies that we observed during the first wave of the pandemic in the municipality of Vo in Italy. The confirmation that all the haplotypes found in this small community derive from a common ancestor haplotype, has allowed us to track the rapid emergence of new variants but lockdown and mass testing efficiently prevented their spread elsewhere.

evolutionary biology↗

Pleiotropic effect of Lactoferrin in the prevention and treatment of COVID-19 infection: in vivo, in silico and in vitro preliminary evidences

Lactoferrin, a multifunctional cationic glycoprotein, secreted by exocrine glands and neutrophils, possesses an antiviral activity extendable to SARS-CoV-2. We performed in vitro assays proving lactoferrin antiviral activity through direct attachment to both virus and cell surface components. This activity varied according to concentration (100/500g/ml), multiplicity of infection (0.1/0.01) and cell type (Vero E6/Caco-2 cells). Interestingly, the in silico results strongly supported the hypothesis of a direct recognition between the lactoferrin and the Spike S glycoprotein, thus hindering the viral entry into the cells. Hence, we conducted a clinical trial to investigate effect and tolerability of a liposomal lactoferrin formulation as a supplementary nutraceutical agent in mild-to-moderate and asymptomatic COVID-19 patients. A total of 92 mild-to-moderate (67/92) and asymptomatic (25/92) COVID-19 patients were recruited and divided in 3 groups according to the administered regimen. Thirty-two patients, 14 hospitalised and 18 in home-based insolation received oral and intranasal liposomal bovine lactoferrin (bLf), 32 hospitalised patients were treated with standard of care treatment (hydroxychloroquine, azitromicin and lopinavir/darunavir), and 28, in home-based isolation, did not take any medication. Furthermore, 32 COVID-19 negative, not-treated, healthy subjects were added as a control group for ancillary analysis. bLf-supplemented COVID-19 patients obtained an earlier and significant (p < 0,0001.) median rRT-PCR SARS-COV-2 RNA negative conversion than standard of care-treated and non-treated COVID-19 patients (14.25 vs 27.13 vs 32.61 days, respectively). In addition, bLf-supplemented COVID-19 patients showed significant fast clinical symptoms recovery than standard of care-treated and non-treated COVID-19 patients. Moreover, in bLf-supplemented patients, a significant decrease of either serum ferritin or IL-6 levels or host iron overload, all parameters characterizing inflammatory processes, were observed. Serum D-dimers was also found significantly decreased following bLf supplement. No adverse events were reported. These in vitro and in vivo observations led us to speculate a potential and safe supplementary role of Blf in the management of mild-to-moderate and asymptomatic COVID-19 patients.

microbiology↗