{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T22:41:15Z","timestamp":1774305675779,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T00:00:00Z","timestamp":1767916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"SaNOtize Research &amp; Development Corp","award":["NA"],"award-info":[{"award-number":["NA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Respiratory viruses such as SARS-CoV-2, influenzas A and B, respiratory syncytial virus (RSV), human metapneumovirus (hMPV), human parainfluenza virus type 3 (HPIV-3), and rhinoviruses remain major causes of global morbidity. Their rapid evolution, high transmissibility, and limited therapeutic options, together with the absence of approved vaccines for several pathogens, highlight the need for broad-acting and pathogen-independent antiviral strategies. Nitric oxide exhibits antiviral activity through redox-dependent mechanisms, including S-nitrosylation of cysteine-containing viral proteins and disruption of redox-sensitive structural domains. Clinical studies conducted during the SARS-CoV-2 pandemic demonstrated that a nitric oxide nasal spray (NONS) rapidly reduced nasal viral load and transmission. In this study, we evaluated the in vitro virucidal activity of the NONS against a panel of clinically relevant respiratory viruses representing four major virus families. Virus suspensions of approximately 104 CCID50 were exposed to a full-strength NONS for contact times ranging from 5 s to 2 min at room temperature, followed by neutralization and quantification of residual infectivity using endpoint dilution assays. The NONS rapidly reduced viral infectivity across all viruses tested, achieving &gt;3 log10 reductions within 2 min. SARS-CoV-2 variants including Alpha, Beta, Gamma, Delta, Omicron BA.1, and XBB 2.0 were reduced to levels at or below the assay detection limit within 30 s to 2 min. Influenza A and B viruses showed the fastest loss of infectivity, reaching detection limits within 10\u201315 s. RSV, hMPV, HPIV-3, and human rhinovirus 14 were similarly inactivated within 1\u20132 min. These findings demonstrate that the NONS exhibits rapid and broad-spectrum virucidal activity against diverse respiratory viruses and supports its potential role in pandemic preparedness but also seasonal use.<\/jats:p>","DOI":"10.3390\/v18010091","type":"journal-article","created":{"date-parts":[[2026,1,9]],"date-time":"2026-01-09T10:35:52Z","timestamp":1767954952000},"page":"91","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Broad-Spectrum Virucidal Activity of Nitric Oxide Nasal Spray (NONS) Against SARS-CoV-2 Variants and Major Respiratory Viruses"],"prefix":"10.3390","volume":"18","author":[{"given":"James","family":"Martins","sequence":"first","affiliation":[{"name":"SaNOtize Research & Development Corp., Vancouver, BC V6P 6T3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Selvarani","family":"Vimalanathan","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 2B5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeremy","family":"Road","sequence":"additional","affiliation":[{"name":"Respiratory Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chris","family":"Miller","sequence":"additional","affiliation":[{"name":"SaNOtize Research & Development Corp., Vancouver, BC V6P 6T3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8880","DOI":"10.1128\/JVI.73.10.8880-8883.1999","article-title":"Inhibition of Influenza Virus Replication by Nitric Oxide","volume":"73","author":"Rimmelzwaan","year":"1999","journal-title":"J. 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