{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T07:08:41Z","timestamp":1767337721878,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,27]],"date-time":"2019-12-27T00:00:00Z","timestamp":1577404800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Australian National Health &amp; Medical Research Council of Australia (NHMRC), Centres of Research Excellence (CRE) grant","award":["APP1107393"],"award-info":[{"award-number":["APP1107393"]}]},{"name":"NHMRC Principal Research Fellowship","award":["1137582"],"award-info":[{"award-number":["1137582"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Two distinct phenomena of airborne transmission of variola virus (smallpox) were described in the pre-eradication era\u2014direct respiratory transmission, and a unique phenomenon of transmission over greater distances, referred to as \u201caerial convection\u201d. We conducted an analysis of data obtained from a systematic review following the PRISMA criteria, on the long-distance transmission of smallpox. Of 8179 studies screened, 22 studies of 17 outbreaks were identified\u201412 had conclusive evidence of aerial convection and five had partially conclusive evidence. Aerial convection was first documented in 1881 in England, when smallpox incidence had waned substantially following mass vaccination, making unusual transmissions noticeable. National policy at the time stipulated spatial separation of smallpox hospitals from other buildings and communities. The evidence supports the transmission of smallpox through aerial convection at distances ranging from 0.5 to 1 mile, and one instance of 15 km related to bioweapons testing. Other explanations are also possible, such as missed chains of transmission, fomites or secondary aerosolization from contaminated material such as bedding. The window of observation of aerial convection was within the 100 years prior to eradication. Aerial convection appears unique to the variola virus and is not considered in current hospital infection control protocols. Understanding potential aerial convection of variola should be an important consideration in planning for smallpox treatment facilities and protecting potential contacts and surrounding communities.<\/jats:p>","DOI":"10.3390\/v12010033","type":"journal-article","created":{"date-parts":[[2019,12,27]],"date-time":"2019-12-27T11:42:47Z","timestamp":1577446967000},"page":"33","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Evidence of Long-Distance Aerial Convection of Variola Virus and Implications for Disease Control"],"prefix":"10.3390","volume":"12","author":[{"given":"Chandini Raina","family":"MacIntyre","sequence":"first","affiliation":[{"name":"Biosecurity Program, The Kirby Institute, UNSW Medicine, University of New South Wales, Sydney, NSW 2052, Australia"},{"name":"College of Health Solutions, Arizona State University, Phoenix, AZ 85004, USA"},{"name":"College of Public Service and Community Solutions, Arizona State University, Phoenix, AZ 85004, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arpita","family":"Das","sequence":"additional","affiliation":[{"name":"Biosecurity Program, The Kirby Institute, UNSW Medicine, University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9905-2307","authenticated-orcid":false,"given":"Xin","family":"Chen","sequence":"additional","affiliation":[{"name":"Biosecurity Program, The Kirby Institute, UNSW Medicine, University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charitha De","family":"Silva","sequence":"additional","affiliation":[{"name":"School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Con","family":"Doolan","sequence":"additional","affiliation":[{"name":"School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Melamed, S., Israely, T., and Paran, N. 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