{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,18]],"date-time":"2026-10-18T02:47:14Z","timestamp":1792291634543,"version":"4.4.0"},"reference-count":47,"publisher":"AIP Publishing","issue":"11","funder":[{"DOI":"10.13039\/100000001","name":"National Science\n              Foundation","doi-asserted-by":"publisher","award":["2031227"],"award-info":[{"award-number":["2031227"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2020,11,1]]},"abstract":"<jats:p>Recent studies have indicated that COVID-19 is an airborne disease, which has driven conservative social distancing and widescale usage of face coverings. Airborne virus transmission occurs through droplets formed during respiratory events (breathing, speaking, coughing, and sneezing) associated with the airflow through a network of nasal and buccal passages. The airflow interacts with saliva\/mucus films where droplets are formed and dispersed, creating a route to transmit SARS-CoV-2. Here, we present a series of numerical simulations to investigate droplet dispersion from a sneeze while varying a series of human physiological factors that can be associated with illness, anatomy, stress condition, and sex of an individual. The model measures the transmission risk utilizing an approximated upper respiratory tract geometry for the following variations: (1) the effect of saliva properties and (2) the effect of geometric features within the buccal\/nasal passages. These effects relate to natural human physiological responses to illness, stress, and sex of the host as well as features relating to poor dental health. The results find that the resulting exposure levels are highly dependent on the fluid dynamics that can vary depending on several human factors. For example, a sneeze without flow in the nasal passage (consistent with congestion) yields a 300% rise in the droplet content at 1.83 m (\u22486 ft) and an increase over 60% on the spray distance 5 s after the sneeze. Alternatively, when the viscosity of the saliva is increased (consistent with the human response to illness), the number of droplets is both fewer and larger, which leads to an estimated 47% reduction in the transmission risk. These findings yield novel insight into variability in the exposure distance and indicate how physiological factors affect transmissibility rates. Such factors may partly relate to how the immune system of a human has evolved to prevent transmission or be an underlying factor driving superspreading events in the COVID-19 pandemic.<\/jats:p>","DOI":"10.1063\/5.0032006","type":"journal-article","created":{"date-parts":[[2020,11,12]],"date-time":"2020-11-12T11:18:52Z","timestamp":1605179932000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":80,"title":["A study of fluid dynamics and human physiology factors driving droplet\n          dispersion from a human sneeze"],"prefix":"10.1063","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8019-8114","authenticated-orcid":false,"given":"D.","family":"Fontes","sequence":"first","affiliation":[{"name":"Florida Space Institute, University of Central Florida 1 , Orlando, Florida 32826,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J.","family":"Reyes","sequence":"additional","affiliation":[{"name":"Mechanical and Aerospace Engineering Department, University of Central Florida 2 , Orlando, Florida 32816,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3204-0165","authenticated-orcid":false,"given":"K.","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Mechanical and Aerospace Engineering Department, University of Central Florida 2 , Orlando, Florida 32816,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.","family":"Kinzel","sequence":"additional","affiliation":[{"name":"Mechanical and Aerospace Engineering Department, University of Central Florida 2 , Orlando, Florida 32816,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2020,11,12]]},"reference":[{"key":"2025052317311702100_c1","article-title":"Coronavirus disease (COVID-19)","author":"World Health Organization","year":"21\n             2020"},{"key":"2025052317311702100_c2","doi-asserted-by":"publisher","first-page":"185","DOI":"10.1016\/j.ijsu.2020.04.018","article-title":"The socio-economic implications\n            of the coronavirus pandemic (COVID-19): A review","volume":"78","year":"2020","journal-title":"Int. J.\n            Surg."},{"key":"2025052317311702100_c3","doi-asserted-by":"publisher","first-page":"611","DOI":"10.1093\/oxfordjournals.aje.a118097","article-title":"On air-borne infection: Study\n            II. Droplets and droplet nuclei","volume":"20","year":"1934","journal-title":"Am. J. Epidemiol."},{"key":"2025052317311702100_c4","doi-asserted-by":"publisher","first-page":"2416","DOI":"10.1056\/nejmoa031349","article-title":"Transmission of the severe\n            acute respiratory syndrome on aircraft","volume":"349","year":"2003","journal-title":"N. Engl. J.\n            Med."},{"key":"2025052317311702100_c5","doi-asserted-by":"publisher","first-page":"053310","DOI":"10.1063\/5.0011960","article-title":"On coughing and airborne\n            droplet transmission to humans","volume":"32","year":"2020","journal-title":"Phys. Fluids"},{"key":"2025052317311702100_c6","doi-asserted-by":"publisher","first-page":"093312","DOI":"10.1063\/5.0024272","article-title":"Weather impact on airborne\n            coronavirus survival","volume":"32","year":"2020","journal-title":"Phys. Fluids"},{"key":"2025052317311702100_c7","doi-asserted-by":"publisher","first-page":"083307","DOI":"10.1063\/5.0021280","article-title":"Transport and fate of human\n            expiratory droplets\u2013A modeling approach","volume":"32","year":"2020","journal-title":"Phys. Fluids"},{"key":"2025052317311702100_c8","doi-asserted-by":"crossref","unstructured":"R.\n            Bhardwaj\n           and A.Agrawal, \u201cLikelihood of survival of\n            coronavirus in a respiratory droplet deposited on a solid surface,\u201d\n            Phys. Fluids32, 061704 (2020); arXiv:2005.10897.10.1063\/5.0012009","DOI":"10.1063\/5.0012009"},{"key":"2025052317311702100_c9","doi-asserted-by":"publisher","first-page":"081905","DOI":"10.1063\/5.0021666","article-title":"Universal trends in human\n            cough airflows at large distances","volume":"32","year":"2020","journal-title":"Phys. Fluids"},{"key":"2025052317311702100_c10","doi-asserted-by":"publisher","first-page":"061708","DOI":"10.1063\/5.0016018","article-title":"Visualizing the\n            effectiveness of face masks in obstructing respiratory jets","volume":"32","year":"2020","journal-title":"Phys. Fluids"},{"key":"2025052317311702100_c11","doi-asserted-by":"publisher","DOI":"10.1093\/infdis\/jiaa189","article-title":"Airborne or droplet\n            precautions for health workers treating coronavirus disease 2019?","year":"2020","journal-title":"J. Infect. Dis."},{"key":"2025052317311702100_c12","doi-asserted-by":"publisher","first-page":"115","DOI":"10.1016\/j.compbiomed.2016.01.022","article-title":"Computer simulations of\n            pressure and velocity fields in a human upper airway during sneezing","volume":"71","year":"2016","journal-title":"Comput. Biol. Med."},{"key":"2025052317311702100_c13","doi-asserted-by":"publisher","first-page":"203","DOI":"10.1016\/j.cmpb.2019.05.031","article-title":"In\n              silico investigation of sneezing in a full real human upper airway using\n            computational fluid dynamics method","volume":"177","year":"2019","journal-title":"Comput. Methods Programs\n            Biomed."},{"key":"2025052317311702100_c14","doi-asserted-by":"publisher","first-page":"537","DOI":"10.1017\/jfm.2014.88","article-title":"Violent expiratory events: On\n            coughing and sneezing","volume":"745","year":"2014","journal-title":"J. Fluid Mech."},{"key":"2025052317311702100_c15","doi-asserted-by":"publisher","first-page":"651","DOI":"10.1164\/rccm.202004-1263PP","article-title":"Coughs and sneezes: Their role in\n            transmission of respiratory viral infections, including SARS-CoV-2","volume":"202","year":"2020","journal-title":"Am. J. Respir. Crit. 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Dis."},{"key":"2025052317311702100_c24","doi-asserted-by":"publisher","first-page":"461","DOI":"10.1016\/j.ijid.2020.05.025","article-title":"Do superspreaders generate\n            new superspreaders? A hypothesis to explain the propagation pattern of\n            COVID-19","volume":"96","year":"2020","journal-title":"Int. J. Infect. Dis."},{"key":"2025052317311702100_c25","doi-asserted-by":"publisher","first-page":"1019","DOI":"10.1001\/jama.1973.03220090039008","article-title":"Rubella in an immunized island\n            population","volume":"223","year":"1973","journal-title":"JAMA, J. Am. Med. 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Oral Maxillofac. Surg."},{"key":"2025052317311702100_c35","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1016\/j.prosdent.2018.03.003","article-title":"Oral health-related quality of\n            life after prosthodontic treatment for patients with partial edentulism: A systematic\n            review and meta-analysis","volume":"121","year":"2019","journal-title":"J. Prosthet. Dent."},{"key":"2025052317311702100_c36","first-page":"137","article-title":"Comments on the feasibility\n            of LES for wings, and on a hybrid RANS\/LES approach","year":"1997"},{"key":"2025052317311702100_c37","first-page":"318","article-title":"A drag coefficient\n            correlation","volume":"77","year":"1935","journal-title":"Z. Ver. Dtsch. 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Heat Transfer, Part B"},{"key":"2025052317311702100_c42","doi-asserted-by":"publisher","first-page":"1525","DOI":"10.2514\/3.8284","article-title":"Numerical study of the turbulent\n            flow past an airfoil with trailing edge separation","year":"1983"},{"key":"2025052317311702100_c43","year":"2018"},{"key":"2025052317311702100_c44","article-title":"Guideline for isolation\n            precautions hospitals","year":"1996"},{"key":"2025052317311702100_c45","doi-asserted-by":"publisher","first-page":"S102","DOI":"10.1016\/j.ajic.2016.06.003","article-title":"Airborne spread of infectious\n            agents in the indoor environment","volume":"44","year":"2016","journal-title":"Am. J. Infect.\n            Control"},{"key":"2025052317311702100_c46","doi-asserted-by":"publisher","first-page":"356","DOI":"10.1017\/s0022112062000762","article-title":"The \u2018starting plume\u2019 in neutral\n            surroundings","volume":"13","year":"1962","journal-title":"J. Fluid Mech."},{"key":"2025052317311702100_c47","doi-asserted-by":"publisher","first-page":"014106","DOI":"10.1063\/1.1823532","article-title":"Vortex dynamics in starting\n            square water jets","volume":"17","year":"2005","journal-title":"Phys. Fluids"}],"container-title":["Physics of Fluids"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/aip.scitation.org\/doi\/am-pdf\/10.1063\/5.0032006","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/aip\/pof\/article-pdf\/doi\/10.1063\/5.0032006\/20532126\/111904_1_5.0032006.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/aip\/pof\/article-pdf\/doi\/10.1063\/5.0032006\/20532126\/111904_1_5.0032006.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T21:31:23Z","timestamp":1748035883000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.aip.org\/pof\/article\/32\/11\/111904\/1032498\/A-study-of-fluid-dynamics-and-human-physiology"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,1]]},"references-count":47,"journal-issue":{"issue":"11","published-print":{"date-parts":[[2020,11,1]]}},"URL":"https:\/\/doi.org\/10.1063\/5.0032006","relation":{},"ISSN":["1070-6631","1089-7666"],"issn-type":[{"value":"1070-6631","type":"print"},{"value":"1089-7666","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2020,11,1]]},"published":{"date-parts":[[2020,11,1]]},"article-number":"111904"}}