{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T21:09:02Z","timestamp":1771103342963,"version":"3.50.1"},"reference-count":178,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,9]],"date-time":"2021-10-09T00:00:00Z","timestamp":1633737600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["AI104960"],"award-info":[{"award-number":["AI104960"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["AI149383"],"award-info":[{"award-number":["AI149383"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004933","name":"Texas A&amp;M University System","doi-asserted-by":"publisher","award":["n\/a"],"award-info":[{"award-number":["n\/a"]}],"id":[{"id":"10.13039\/100004933","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Bacille Calmette\u2013Gu\u00e9rin (BCG) vaccination, widely used throughout the world to protect against infant tuberculous meningitis and miliary tuberculosis (TB), can provide broad non-specific protection against infectious respiratory diseases in certain groups. Interest in BCG has seen a resurgence within the scientific community as the mechanisms for non-specific protection have begun to be elucidated. The impact of the COVID-19 pandemic on nearly every aspect of society has profoundly illustrated the pressure that respiratory infections can place on a national healthcare system, further renewing interest in BCG vaccination as a public health policy to reduce the burden of those illnesses. However, the United States does not recommend BCG vaccination due to its variable effectiveness against adult TB, the relatively low risk of Mycobacterium tuberculosis infection in most of the United States, and the vaccine\u2019s interference with tuberculin skin test reactivity that complicates TB screening. In this review, we explore the broad immune training effects of BCG vaccination and literature on the effects of BCG vaccination on COVID-19 spread, disease severity, and mortality. We further discuss barriers to scheduled BCG vaccination in the United States and how those barriers could potentially be overcome.<\/jats:p>","DOI":"10.3390\/microorganisms9102120","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:29Z","timestamp":1633901849000},"page":"2120","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["COVID-19 and Beyond: Exploring Public Health Benefits from Non-Specific Effects of BCG Vaccination"],"prefix":"10.3390","volume":"9","author":[{"given":"Kent J.","family":"Koster","sequence":"first","affiliation":[{"name":"Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, 8447 Riverside Pkwy, Bryan, TX 77807, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hilary L.","family":"Webb","sequence":"additional","affiliation":[{"name":"Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, 8447 Riverside Pkwy, Bryan, TX 77807, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3058-2702","authenticated-orcid":false,"given":"Jeffrey D.","family":"Cirillo","sequence":"additional","affiliation":[{"name":"Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, 8447 Riverside Pkwy, Bryan, TX 77807, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1007\/978-3-319-64371-7_8","article-title":"Evolution and Strain Variation in BCG","volume":"1019","author":"Abdallah","year":"2017","journal-title":"Adv. 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