{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T16:47:22Z","timestamp":1791478042625,"version":"4.3.4"},"reference-count":45,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T00:00:00Z","timestamp":1741046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Electric Power Research Institute (EPRI)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Airborne transmission has been implicated as a major route for the spread of microorganisms, causing infectious disease outbreaks worldwide. This has been emphasized by the recent COVID-19 pandemic, caused by the SARS-CoV-2 virus. There is thus an unmet need to develop technologies that arrest the spread of airborne infectious diseases by inactivating viruses in the air. In this study, the efficacy of two commercially available air ionizer systems for inactivating the bacteriophage MS2, which has been utilized as a surrogate of SARS-CoV-2 as well as a surrogate of noroviruses, was assessed. An experimental test apparatus similar to an HVAC duct system was utilized for the efficacy testing. Each of the two ionizer devices was challenged with viral aerosols of the bacteriophage MS2. The results indicate that the two ionizers were able to reduce the concentration of bacteriophage MS2 virus in the air by 82.02% and 81.72%, respectively. These results point to the efficacy of these ionizer devices in inactivating airborne microorganisms and thus making them an important tool in arresting the spread of infectious diseases. More studies are needed to assess their efficacy against other important airborne viruses such as influenza and strains of the SARS-CoV-2 virus.<\/jats:p>","DOI":"10.3390\/microorganisms13030593","type":"journal-article","created":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T13:31:31Z","timestamp":1741095091000},"page":"593","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["An Assessment of the Efficacy of Commercial Air Ionizer Systems Against a SARS-CoV-2 Surrogate"],"prefix":"10.3390","volume":"13","author":[{"given":"Nachiket","family":"Vaze","sequence":"first","affiliation":[{"name":"Nanoscience and Advanced Materials Center, Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ 08854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brittany","family":"Gold","sequence":"additional","affiliation":[{"name":"Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Douglas","family":"Lindsey","sequence":"additional","affiliation":[{"name":"The Electric Power Research Institute, Palo Alto, CA 94304, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5393-0733","authenticated-orcid":false,"given":"Matthew D.","family":"Moore","sequence":"additional","affiliation":[{"name":"Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petros","family":"Koutrakis","sequence":"additional","affiliation":[{"name":"Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02215, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2484-9143","authenticated-orcid":false,"given":"Philip","family":"Demokritou","sequence":"additional","affiliation":[{"name":"Nanoscience and Advanced Materials Center, Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ 08854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1016\/j.arcmed.2020.04.020","article-title":"A Review of Current Interventions for COVID-19 Prevention","volume":"51","author":"Pradhan","year":"2020","journal-title":"Arch. Med. Res."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Abkar, L., Zimmermann, K., Dixit, F., Kheyrandish, A., and Mohseni, M. (2022). 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