IntroductionRecent virus epidemics and rising antibiotic resistance highlight the importance of hygiene measures to prevent and control outbreaks. We investigated the in vitro bactericidal and virucidal efficacy of povidone-iodine (PVP-I) 7% gargle/mouthwash at defined dilution against oral and respiratory tract pathogens.MethodsPVP-I was tested against Klebsiella pneumoniae and Streptococcus pneumoniae according to bactericidal quantitative suspension test EN13727 and against severe acute respiratory syndrome and Middle East respiratory syndrome coronaviruses (SARS-CoV and MERS-CoV), rotavirus strain Wa and influenza virus A subtype H1N1 according to virucidal quantitative suspension test EN14476. PVP-I 7% gargle/mouthwash was diluted 1:30 with water to a concentration of 0.23% (the recommended concentration for “real-life” use in Japan) and tested at room temperature under clean conditions [0.3 g/l bovine serum albumin (BSA), viruses only] and dirty conditions (3.0 g/l BSA + 3.0 ml/l erythrocytes) as an interfering substance for defined contact times (minimum 15 s). Rotavirus was tested without protein load. A ≥ 5 log10 (99.999%) decrease of bacteria and ≥ 4 log10 (99.99%) reduction in viral titre represented effective bactericidal and virucidal activity, respectively, per European standards.ResultsPVP-I gargle/mouthwash diluted 1:30 (equivalent to a concentration of 0.23% PVP-I) showed effective bactericidal activity against Klebsiella pneumoniae and Streptococcus pneumoniae and rapidly inactivated SARS-CoV, MERS-CoV, influenza virus A (H1N1) and rotavirus after 15 s of exposure.ConclusionPVP-I 7% gargle/mouthwash showed rapid bactericidal activity and virucidal efficacy in vitro at a concentration of 0.23% PVP-I and may provide a protective oropharyngeal hygiene measure for individuals at high risk of exposure to oral and respiratory pathogens.FundingMundipharma Research GmbH & Co. KG (MRG).

IntroductionSince the first case of Middle East Respiratory Syndrome coronavirus (MERS-CoV) infection was reported in 2012, the virus has infected more than 1300 individuals in 26 countries, and caused more than 480 deaths. Human-to-human transmission requires close contact, and has typically occurred in the healthcare setting. Improved global awareness, together with improved hygiene practices in healthcare facilities, has been highlighted as key strategies in controlling the spread of MERS-CoV. This study tested the in vitro efficacy of three formulations of povidone iodine (PVP-I: 4% PVP-I skin cleanser, 7.5% PVP-I surgical scrub, and 1% PVP-I gargle/mouthwash) against a reference virus (Modified vaccinia virus Ankara, MVA) and MERS-CoV.MethodsAccording to EN14476, a standard suspension test was used to assess virucidal activity against MVA and large volume plating was used for MERS-CoV. All products were tested under clean (0.3 g/L bovine serum albumin, BSA) and dirty conditions (3.0 g/L BSA + 3.0 mL/L erythrocytes), with application times of 15, 30, and 60 s for MVA, and 15 s for MERS-CoV. The products were tested undiluted, 1:10 and 1:100 diluted against MVA, and undiluted against MERS-CoV.ResultsA reduction in virus titer of ≥4 log10 (corresponding to an inactivation of ≥99.99%) was regarded as evidence of virucidal activity. This was achieved versus MVA and MERS-CoV, under both clean and dirty conditions, within 15 s of application of each undiluted PVP-I product.ConclusionThese data indicate that PVP-I-based hand wash products for potentially contaminated skin, and PVP-I gargle/mouthwash for reduction of viral load in the oral cavity and the oropharynx, may help to support hygiene measures to prevent transmission of MERS-CoV.FundingMundipharma Research GmbH & Co.Electronic supplementary materialThe online version of this article (doi:10.1007/s40121-015-0091-9) contains supplementary material, which is available to authorized users.

Cytotoxic T cells recognize viral proteins as peptide fragments which are produced in the cytosol and transported on major histocompatibility complex (MHC) class I proteins to the cell surface. Viral peptides that meet the stringent binding characteristics of class I proteins are generated by the 20S proteasome. The interferon (IFN)-gamma-inducible activator of the 20S proteasome, PA28, strongly influences the proteasomal cleavage pattern in vitro. This led us to investigate whether changes in cellular levels of PA28 affect the efficiency of viral antigen processing. A mouse fibroblast line expressing the murine cytomegalovirus pp89 protein was transfected with either the human or murine gene encoding the PA28alpha subunit, which is sufficient to activate the peptide-hydrolysing activity of the 20S proteasome in vitro. Here we report that enhanced expression of PA28alpha at a level similar to that obtained after IFN-gamma induction resulted in a marked enhancement of recognition by pp89-specific cytotoxic T cells; the presentation of influenza nucleoprotein was also significantly improved. These results demonstrate a fundamental in vivo function for PA28alpha in antigen processing.

Introduction: As of 22 June 2020, Severe Acute Respiratory Syndrome (SARS)-coronavirus (CoV)-2 has infected more than 8.95 million people worldwide, causing [ 468,000 deaths. The virus is transmitted through respiratory droplets and physical contact from contaminated surfaces to the mucosa. Hand hygiene and oral decontamination among other measures are key to preventing the spread of the virus. We report the in vitro virucidal activity of topical and oral povidone-iodine (PVP-I) products against SARS-CoV-2. Methods: Suspension assays were used to assess the virucidal activity of PVP-I against SARS-CoV-2. Products were tested at a contact time of 30 s for virucidal activity. Viral titres were calculated using the Spearman-Kärber method and reported as median tissue culture infectious dose (TCID 50)/mL. Results: All four products [antiseptic solution (PVP-I 10%), skin cleanser (PVP-I 7.5%), gargle and mouth wash (PVP-I 1%) and throat spray (PVP-I 0.45%)] achieved C 99.99% virucidal activity against SARS-CoV-2, corresponding to C 4 log 10 reduction of virus titre, within 30 s of contact. Conclusion: This study provides evidence of rapid and effective virucidal activity of PVP-I against SARS-CoV-2. PVP-I-based products are widely available for medical and personal use for hand hygiene and oral decontamination, and could be readily integrated into coronavirus disease, COVID-19, infection control measures in hospital and community settings.

With reports of vancomycin-resistant enterococci recently emerging in hospital settings, renewed focus is turning to the importance of multifaceted infection prevention efforts. Careful compliance with established hygiene practices by healthcare workers together with effective antiseptic options is essential for the protection of patients from infectious agents. For over 60 years, povidone iodine (PVP-I) formulations have been shown to limit the impact and spread of infectious diseases with potent antiviral, antibacterial and antifungal effects. In addition to a lack of reported resistance, the benefits of PVP-I include an excellent safety profile and a broad spectrum of effect due to its multimodal action. Studies have shown that hand washing with PVP-I-based antiseptics is effective for the decontamination of skin, while PVP-I mouthwashes and gargles significantly reduce viral load in the oral cavity and the oropharynx. The importance of PVP-I has been emphasised by its inclusion in the World Health Organization’s list of essential medicines, and high potency for virucidal activity has been observed against viruses of significant global concern, including hepatitis A and influenza, as well as the Middle-East Respiratory Syndrome and Sudden Acute Respiratory Syndrome coronaviruses. Together with its diverse applications in antimicrobial control, broad accessibility across the globe, and outstanding safety and tolerability profile, PVP-I offers an affordable, potent, and widely available antiseptic option.Funding Mundipharma Singapore Holding Pte Limited.