Manuela Donalisio

The 9th National Congress of the Italian Society for Virology (SIV-ISV), entitled “One Virology—One Health”, took place in Turin at the Centro Congressi Lingotto from 22 to 24 June 2025. The meeting highlighted recent multidisciplinary and translational developments in virology, with a strong focus on the integration of the One Health perspective. Major themes included viral emergence and surveillance, genomic sequencing and bioinformatics, virus–host interactions, viral immunology and vaccines, structural and physical virology, environmental and food virology, zoonoses and animal infections, diagnostics and antiviral therapy, virus-based biotechnology and plant virology. The Congress aimed to: (i) bring together clinicians, basic researchers, veterinarians, environmental microbiologists, bioinformaticians, public-health professionals and industry to share methodologies and best practices; (ii) provide an interactive scientific environment promoting discussion and collaboration between senior investigators and trainees through plenaries, joint society sessions, invited talks, oral communications selected from abstracts, poster sessions, and mentoring panels; and (iii) identify priorities and inspire new research directions at the interface of human, animal and environmental health. More than 400 participants from national and international institutions attended the meeting, featuring distinguished plenary speakers, joint sessions with global networks, and numerous presentations of original unpublished data. This report summarizes the meeting’s scientific highlights, cross-disciplinary discussions, and proposed actions to strengthen One Health surveillance, computational infrastructures, and translational applications of viral biology.

Pathogenic air and water contaminations present major health issues nowadays. Filter-based protective devices have been commonly utilized to capture airborne or waterborne microorganisms and viruses in order to reduce or inhibit the transmission of infectious diseases. Some approaches to extend the functionality of filtering devices and to further enhance their capability to inactive pathogens include the application of antimicrobial coatings on the filter surface. In this regard, the current work aims to develop innovative coatings with antiviral and antibacterial properties composed of a chitosan matrix incorporating bioactive glass (BG) nanoparticles or silver nitrate (AgNO₃) on metallic filters by using electrophoretic deposition. The so-produced chitosan/BG- and chitosan/AgNO₃-coated filters were characterized in terms of their morphology, chemical composition, filtering capability, antibacterial properties against Staphylococcus aureus, and antiviral activity against coronavirus OC43, rhinovirus, adenovirus, and influenza virus. The results confirmed that chitosan/AgNO₃ and chitosan/BG coatings exhibited no blockage of the filter pores. The bubble point values for both coating types were similar to the measurements of uncoated filters, suggesting intact filtration capability after the application of the coatings. The antibacterial assay showed the antibacterial activity of >99% for both chitosan/AgNO₃ and chitosan/BG coatings against S. aureus. Finally, chitosan/AgNO₃-coated filters showed antiviral activity against three out of the four tested viruses (HCoV-OC43, HRV-A1, and IFV-AH3N2) and exerted a partial antiviral action against AdV-5. On the other hand, chitosan/BG-coated filters were active against all tested respiratory viruses. The outcomes of this study evidenced that the developed multimaterial coatings could serve as a suitable platform to produce antimicrobial filtering systems for a broad-spectrum application.

Cell-based phenotypic screening of a privileged in-house library composed of pyridobenzothiazolone (PBTZ) analogues was conducted against representative viruses responsible for common respiratory tract infections in humans, i.e., respiratory syncytial virus (RSV), human coronavirus type OC43 (HCoV-OC43), and influenza virus type A (IFV-A). We identified a compound with broad-spectrum inhibitory activity against multiple strains of RSV, HCoV, and IFV, with EC₅₀ values in the low micromolar range and cell-independent activity. Its antiviral activity and cytocompatibility were confirmed in a fully differentiated 3D model of the bronchial epithelium mimicking the in vivo setting. The hit compound enters cells and localizes homogeneously in the cytosol, inhibiting replicative phases in a virus-specific manner. Overall, the selected PBTZ represents a good starting point for further preclinical development as a broad-spectrum antiviral agent that could address the continuous threat of new emerging pathogens and the rising issue of antiviral resistance.

After the end of the COVID-19 public health emergency, we analysed the relationship between Systemic Lupus Erythematosous (SLE) and COVID-19 from the virologist’s perspective based on recent findings. SLE and COVID-19 co-morbidity present unique challenges, as individuals with SLE may be at increased risk for severe COVID-19 illness due to immune system abnormalities and ongoing therapies. Effective management of both diseases requires careful monitoring, adherence to vaccination programs, preventive measures and approved and patient-tailored therapies. This review covers various aspects, including the clinical outcome of SLE patients infected by SARS-CoV-2, the impact of this infection on SLE onset or flare-ups and the benefits of vaccination for this population. Furthermore, this review presents the most recent recommendations on clinical management of COVID-19 in rheumatic patients, including those with SLE, discussing the currently available therapeutic options. Finally, we explore the most effective tools for SARS-CoV-2 diagnosis in autoimmune conditions and examine prognostic biomarkers in COVID-19 rheumatic patients with potential implications on their clinical oversight. By adopting a comprehensive approach, we address these complexities from the virologist’s perspective, aiming to improve health care for this vulnerable population.

SARS-CoV-2 and HCoV-OC43 belong to the same β genus of the Coronaviridae family. SARS-CoV-2 was responsible for the recent COVID-19 pandemic, and HCoV-OC43 is the etiological agent of mild upper respiratory tract infections. SARS-COV-2 and HCoV-OC43 co-infections were found in children with respiratory symptoms during the COVID-19 pandemic. The two β-coronaviruses share a high degree of homology between the 3CLpro active sites, so much so that the safer HCoV-OC43 has been suggested as a tool for the identification of new anti-SARS-COV-2 agents. Compounds 5 and 24 inhibited effectively both Wuhan and British SARS-CoV-2 patient isolates in Vero E6 cells and the HCoV-OC43 in MRC-5 cells at low micromolar concentrations. The inhibition was apparently exerted via targeting the 3CLpro active sites of both viruses. Compounds 5 and 24 at 100 μM inhibited the SARS-CoV-2 3CLpro activity of 61.78 and 67.30%, respectively. These findings highlight 5 and 24 as lead compounds of a novel class of antiviral agents with the potential to treat SARS-COV-2 and HCoV-OC43 infections.

Valacyclovir (VACV) was developed as a prodrug of the most common anti-herpetic drug Acyclovir (ACV), aiming to enhance its bioavailability. Nevertheless, prolonged VACV oral treatment may lead to the development of important side effects. Nanotechnology-based formulations for vaginal administration represent a promising approach to increase the concentration of the drug at the site of infection, limiting systemic drug exposure and reducing systemic toxicity. In this study, VACV-loaded nanodroplet (ND) formulations, optimized for vaginal delivery, were designed. Cell-based assays were then carried out to evaluate the antiviral activity of VACV loaded in the ND system. The chitosan-shelled ND exhibited an average diameter of about 400 nm and a VACV encapsulation efficiency of approximately 91% and was characterized by a prolonged and sustained release of VACV. Moreover, a modification of chitosan shell with an anionic cyclodextrin, sulfobutyl ether β-cyclodextrin (SBEβCD), as a physical cross-linker, increased the stability and mucoadhesion capability of the nanosystem. Biological experiments showed that SBEβCD-chitosan NDs enhanced VACV antiviral activity against the herpes simplex viruses type 1 and 2, most likely due to the long-term controlled release of VACV loaded in the ND and an improved delivery of the drug in sub-cellular compartments.

Three gallium(III)- and thallium(III)-containing polyoxopalladates (POPs) have been synthesized and structurally characterized in the solid state and in solution, namely, the phosphate-capped 12-palladate nanocubes [XPd₁₂O₈(PO₄)₈]^13- (X = Ga^III, GaPd₁₂P₈; X = Tl^III, TlPd₁₂P₈) and the 23-palladate double-cube [Tl₂^IIIPd₂₃P₁₄O₇₀(OH)₂]^20- (Tl₂Pd₂₃P₁₄). The cuboid POPs, GaPd₁₂P₈ and TlPd₁₂P₈, are solution stable as verified by the respective ³¹P, ⁷¹Ga, and ²⁰⁵Tl nuclear magnetic resonance (NMR) spectra. Of prime interest, the spin-spin coupling schemes allowed for an intimate study of the solution behavior of the Tl^III-containing POPs via a combination of ³¹P and ²⁰⁵Tl NMR, including the stoichiometry of the major fragments of Tl₂Pd₂₃P₁₄. Moreover, biological studies demonstrated the antitumor and antiviral activity of GaPd₁₂P₈ and TlPd₁₂P₈, which were validated to be as efficient as cis-platinum against human melanoma and acute promyelocytic leukemia cells. Furthermore, GaPd₁₂P₈ and TlPd₁₂P₈ exerted inhibitory activity against two herpetic viruses, HSV-2 and HCMV, in a dose-response manner.

Background There is extensive evidence that Holder pasteurization (HoP) (30 min at 62.5 °C) has harmful effects on the bioactivities of human milk (HM). We previously demonstrated that lowering HoP temperature is sufficient to inactivate Cytomegalovirus (HCMV). Here, we analyzed the effect of lowering time/temperature on the antiviral activity against HCMV and IgA levels of HM. Methods Eighty HM samples from five mothers were pasteurized in a range of temperature (62.5–56 °C) and time (40–10 min) in a conventional setting of Human Milk Bank. Unpasteurized HM from each mother was used as control. The samples were assayed against HCMV-AD169 strain in cell cultures and IgA levels were determined by ELISA. Results All HM samples exhibited anti-HCMV activity, to a different extent. An improvement of antiviral activity was observed in samples treated at 60, 58 and 56 °C compared to those at 62.5 °C, with ID₅₀ values near those of unpasteurized milk. Similarly, better retention in IgA levels was observed by reducing the temperature of treatment. Conclusions We demonstrated that a 2.5 °C reduction of heat treatment significantly preserved the IgA content and fully restored the anti-HCMV activity of HM, supporting this variant of HoP as a valid alternative to preserve HM bioactivities. Impact This work questions the standard HoP and opens the debate on whether the pasteurization temperature commonly used in Human Milk Banks should be lowered to better preserve the biological components of the milk. A reduction of HoP temperature at 60 °C determined a significant preservation of anti-HCMV activity and IgA content of donor HM, compared to standard HoP. This alternative HoP is highly feasible compared to other substitute pasteurization techniques, since it would employ the same pasteurizer equipment found in most Human Milk Banks.