Airborne transmission

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Infected people generate larger droplets and aerosols which can infect over longer distances Aerosol transmission.png
Infected people generate larger droplets and aerosols which can infect over longer distances

A poster outlining precautions for airborne transmission in healthcare settings. It is intended to be posted outside rooms of patients with an infection that can spread through airborne transmission. Airborne Precautions poster.pdf
A poster outlining precautions for airborne transmission in healthcare settings. It is intended to be posted outside rooms of patients with an infection that can spread through airborne transmission.
Video explainer on reducing airborne pathogen transmission indoors

Airborne transmission or aerosol transmission is transmission of an infectious disease through small particles suspended in the air. [2] Infectious diseases capable of airborne transmission include many of considerable importance both in human and veterinary medicine. The relevant infectious agent may be viruses, bacteria, or fungi, and they may be spread through breathing, talking, coughing, sneezing, raising of dust, spraying of liquids, flushing toilets, or any activities which generate aerosol particles or droplets.

Contents

Infectious aerosols: physical terminology

Aerosol transmission has traditionally been considered distinct from transmission by droplets, but this distinction is no longer used. [3] [4] Respiratory droplets were thought to rapidly fall to the ground after emission: [5] but smaller droplets and aerosols also contain live infectious agents, and can remain in the air longer and travel farther. [4] [6] [7] Individuals generate aerosols and droplets across a wide range of sizes and concentrations, and the amount produced varies widely by person and activity. [8] Larger droplets greater than 100 μm usually settle within 2 m. [8] [5] Smaller particles can carry airborne pathogens for extended periods of time. While the concentration of airborne pathogens is greater within 2m, they can travel farther and concentrate in a room. [4]

The traditional size cutoff of 5 μm between airborne and respiratory droplets has been discarded, as exhaled particles form a continuum of sizes whose fates depend on environmental conditions in addition to their initial sizes. This error has informed hospital based transmission based precautions for decades. [8] Indoor respiratory secretion transfer data suggest that droplets/aerosols in the 20 μm size range initially travel with the air flow from cough jets and air conditioning like aerosols, [9] but fall out gravitationally at a greater distance as "jet riders". [9] As this size range is most efficiently filtered out in the nasal mucosa, [10] the primordial infection site in COVID-19, aerosols/droplets [11] in this size range may contribute to driving the COVID-19 pandemic.

Overview

Airborne diseases can be transmitted from one individual to another through the air. The pathogens transmitted may be any kind of microbe, and they may be spread in aerosols, dust or droplets. The aerosols might be generated from sources of infection such as the bodily secretions of an infected individual, or biological wastes. Infectious aerosols may stay suspended in air currents long enough to travel for considerable distances; sneezes, for example, can easily project infectious droplets for dozens of feet (ten or more meters). [12]

Airborne pathogens or allergens typically enter the body via the nose, throat, sinuses and lungs. Inhalation of these pathogens affects the respiratory system and can then spread to the rest of the body. Sinus congestion, coughing and sore throats are examples of inflammation of the upper respiratory airway. Air pollution plays a significant role in airborne diseases. Pollutants can influence lung function by increasing air way inflammation. [13]

Common infections that spread by airborne transmission include SARS-CoV-2; [14] measles morbillivirus, [15] chickenpox virus; [16] Mycobacterium tuberculosis , influenza virus, enterovirus, norovirus and less commonly other species of coronavirus, adenovirus, and possibly respiratory syncytial virus. [17] Some pathogens which have more than one mode of transmission are also anisotropic, meaning that their different modes of transmission can cause different kinds of diseases, with different levels of severity. Two examples are the bacterias Yersinia pestis (which causes plague) and Francisella tularensis (which causes tularaemia), which both can cause severe pneumonia, if transmitted via the airborne route through inhalation. [18]

Poor ventilation enhances transmission by allowing aerosols to spread undisturbed in an indoor space. [19] Crowded rooms are more likely to contain an infected person. The longer a susceptible person stays in such a space, the greater chance of transmission. Airborne transmission is complex, and hard to demonstrate unequivocally [20] but the Wells-Riley model can be used to make simple estimates of infection probability. [21]

Some airborne diseases can affect non-humans. For example, Newcastle disease is an avian disease that affects many types of domestic poultry worldwide that is airborne. Poultry animals are often also airborne. [22]

It has been suggested that airborne transmission should be classified as being either obligate, preferential, or opportunistic, although there is limited research that show the importance of each of these categories. [23] Obligate airborne infections spread only through aerosols; the most common example of this category is tuberculosis. Preferential airborne infections, such as chicken pox, can be obtained through different routes, but mainly by aerosols. Opportunistic airborne infections such as influenza typically transmit through other routes; however, under favourable conditions, aerosol transmission can occur. [24]

Transmission efficiency

Environmental factors influence the efficacy of airborne disease transmission; the most evident environmental conditions are temperature and relative humidity. [25] [26] The transmission of airborne diseases is affected by all the factors that influence temperature and humidity, in both meteorological (outdoor) and human (indoor) environments. Circumstances influencing the spread of droplets containing infectious particles can include pH, salinity, wind, air pollution, and solar radiation as well as human behavior. [27]

Airborne infections usually land in the respiratory system, with the agent present in aerosols (infectious particles < 5 μm in diameter). [28] This includes dry particles, often the remnant of an evaporated wet particle called nuclei, and wet particles.

Prevention

A layered risk-management approach to slowing the spread of a transmissible disease attempts to minimize risk through multiple layers of interventions. Each intervention has the potential to reduce risk. A layered approach can include interventions by individuals (e.g. mask wearing, hand hygiene), institutions (e.g. surface disinfection, ventilation, and air filtration measures to control the indoor environment), the medical system (e.g. vaccination) and public health at the population level (e.g. testing, quarantine, and contact tracing). [4]

Preventive techniques can include disease-specific immunization as well as nonpharmaceutical interventions such as wearing a respirator and limiting time spent in the presence of infected individuals. [41] Wearing a face mask can lower the risk of airborne transmission to the extent that it limits the transfer of airborne particles between individuals. [42] The type of mask that is effective against airborne transmission is dependent on the size of the particles. While fluid-resistant surgical masks prevent large droplet inhalation, smaller particles which form aerosols require a higher level of protection with filtration masks rated at N95 (US) or FFP3 (EU) required. [43] Use of FFP3 masks by staff managing patients with COVID-19 reduced acquisition of COVID-19 by staff members. [44]

Engineering solutions which aim to control or eliminate exposure to a hazard are higher on the hierarchy of control than personal protective equipment (PPE). At the level of physically based engineering interventions, effective ventilation and high frequency air changes, or air filtration through high efficiency particulate filters, reduce detectable levels of virus and other bioaerosols, improving conditions for everyone in an area. [45] [4] [46] Portable air filters, such as those tested in Conway Morris A et al. present a readily deployable solution when existing ventilation is inadequate, for instance in repurposed COVID-19 hospital facilities. [46]

The United States Centers for Disease Control and Prevention (CDC) advises the public about vaccination and following careful hygiene and sanitation protocols for airborne disease prevention. [47] Many public health specialists recommend physical distancing (also known as social distancing) to reduce transmission. [48]

A 2011 study concluded that vuvuzelas (a type of air horn popular e.g. with fans at football games) presented a particularly high risk of airborne transmission, as they were spreading a much higher number of aerosol particles than e.g., the act of shouting. [49]

Exposure does not guarantee infection. The generation of aerosols, adequate transport of aerosols through the air, inhalation by a susceptible host, and deposition in the respiratory tract are all important factors contributing to the over-all risk for infection. Furthermore, the infective ability of the virus must be maintained throughout all these stages. [50] In addition the risk for infection is also dependent on host immune system competency plus the quantity of infectious particles ingested. [41] Antibiotics may be used in dealing with airborne bacterial primary infections, such as pneumonic plague. [51]

See also

Related Research Articles

In medicine, public health, and biology, transmission is the passing of a pathogen causing communicable disease from an infected host individual or group to a particular individual or group, regardless of whether the other individual was previously infected. The term strictly refers to the transmission of microorganisms directly from one individual to another by one or more of the following means:

<span class="mw-page-title-main">Surgical mask</span> Mouth and nose cover against bacterial aerosols

A surgical mask, also known by other names such as a medical face mask or procedure mask, is a personal protective equipment used by healthcare professionals that serves as a mechanical barrier that interferes with direct airflow in and out of respiratory orifices. This helps reduce airborne transmission of pathogens and other aerosolized contaminants between the wearer and nearby people via respiratory droplets ejected when sneezing, coughing, forceful expiration or unintentionally spitting when talking, etc. Surgical masks may be labeled as surgical, isolation, dental or medical procedure masks.

<span class="mw-page-title-main">Natural reservoir</span> Type of population in infectious disease ecology

In infectious disease ecology and epidemiology, a natural reservoir, also known as a disease reservoir or a reservoir of infection, is the population of organisms or the specific environment in which an infectious pathogen naturally lives and reproduces, or upon which the pathogen primarily depends for its survival. A reservoir is usually a living host of a certain species, such as an animal or a plant, inside of which a pathogen survives, often without causing disease for the reservoir itself. By some definitions a reservoir may also be an environment external to an organism, such as a volume of contaminated air or water.

A fomite or fomes is any inanimate object that, when contaminated with or exposed to infectious agents, can transfer disease to a new host.

<span class="mw-page-title-main">Wells curve</span> Science of medicine

The Wells curve is a diagram, developed by W. F. Wells in 1934, which describes what is expected to happen to small droplets once they have been exhaled into air. Coughing, sneezing, and other violent exhalations produce high numbers of respiratory droplets derived from saliva and/or respiratory mucus, with sizes ranging from about 1 μm to 2 mm. Wells' insight was that such droplets would have two distinct fates, depending on their sizes. The interplay of gravity and evaporation means that droplets larger than a humidity-determined threshold size would fall to the ground due to gravity, while droplets smaller than this size would quickly evaporate, leaving a dry residue that drifts in the air. Since droplets from an infected person may contain infectious bacteria or viruses, these processes influence transmission of respiratory diseases.

<span class="mw-page-title-main">Respiratory droplet</span> Type of particle formed by breathing

A respiratory droplet is a small aqueous droplet produced by exhalation, consisting of saliva or mucus and other matter derived from respiratory tract surfaces. Respiratory droplets are produced naturally as a result of breathing, speaking, sneezing, coughing, or vomiting, so they are always present in our breath, but speaking and coughing increase their number.

A toilet plume is the cloud like dispersal of potentially infectious microscopic sewage particles & water vapor as a result of flushing a toilet. Day to day use of a toilet by healthy individuals is considered to be of a lower health risk. However this dynamic completely changes if an individual is fighting an illness and currently shedding out large quantities of an infectious virulent pathogen in their urine, feces or vomitus. There is evidence that specific pathogens such as norovirus or SARS coronavirus could potentially be spread by toilet aerosols, but as of 2015 no direct experimental studies had refuted actual disease transmission from toilet aerosols. It has been hypothesized that dispersal of pathogens may be reduced by closing the toilet lid before flushing, and by using toilets with lower flush energy. 2024 Science empirically built on to this theory, by illustrating that the viruses that toilet plume contains still spreads out the gaps in the seat onto the walls and concentrating on the surrounding floors.

<span class="mw-page-title-main">Dental aerosol</span> Hazardous biological compound

A dental aerosol is an aerosol that is produced from dental instrument, dental handpieces, three-way syringes, and other high-speed instruments. These aerosols may remain suspended in the clinical environment. Dental aerosols can pose risks to the clinician, staff, and other patients. The heavier particles contained within the aerosols are likely to remain suspended in the air for relatively short period and settle quickly onto surfaces, however, the lighter particles may remain suspended for longer periods and may travel some distance from the source. These smaller particles are capable of becoming deposited in the lungs when inhaled and provide a route of diseases transmission. Different dental instruments produce varying quantities of aerosol, and therefore are likely to pose differing risks of dispersing microbes from the mouth. Air turbine dental handpieces generally produce more aerosol, with electric micromotor handpieces producing less, although this depends on the configuration of water coolant used by the handpiece.

<span class="mw-page-title-main">Workplace hazard controls for COVID-19</span> Prevention measures for COVID-19

Hazard controls for COVID-19 in workplaces are the application of occupational safety and health methodologies for hazard controls to the prevention of COVID-19. Multiple layers of controls are recommended, including measures such as remote work and flextime, personal protective equipment (PPE) and face coverings, social distancing, and enhanced cleaning programs. Recently, engineering controls have been emphasized, particularly stressing the importance of HVAC systems meeting a minimum of 5 air changes per hour with ventilation or MERV-13 filters, as well as the installation of UVGI systems in public areas.

An aerosol-generating procedure (AGP) is a medical or health-care procedure that a public health agency such as the World Health Organization or the United States Centers for Disease Control and Prevention (CDC) has designated as creating an increased risk of transmission of an aerosol borne contagious disease, such as COVID-19. The presumption is that the risk of transmission of the contagious disease from a patient having an AGP performed on them is higher than for a patient who is not having an AGP performed upon them. This then informs decisions on infection control, such as what personal protective equipment (PPE) is required by a healthcare worker performing the medical procedure, or what PPE healthcare workers are allowed to use.

Lydia Bourouiba is an Esther and Harold E. Edgerton Professor, an Associate Professor in the Civil and Environmental Engineering and Mechanical Engineering departments, and in the Institute for Medical Engineering and Science at the Massachusetts Institute of Technology. She is also a Harvard-MIT Health Sciences and Technology Faculty, and Affiliate Faculty of Harvard Medical School. She directs the Fluid Dynamics of Disease Transmission Laboratory at MIT.

In epidemiology, a non-pharmaceutical intervention (NPI) is any method used to reduce the spread of an epidemic disease without requiring pharmaceutical drug treatments. Examples of non-pharmaceutical interventions that reduce the spread of infectious diseases include wearing a face mask and staying away from sick people.

<span class="mw-page-title-main">Linsey Marr</span> American scientist

Linsey Chen Marr is an American scientist who is the Charles P. Lunsford Professor of Civil and Environmental Engineering at Virginia Tech. Her research considers the interaction of nanomaterials and viruses with the atmosphere. During the COVID-19 pandemic Marr studied how SARS-CoV-2 and other airborne pathogens could be transported in air. In 2023, she was elected to the National Academy of Engineering and named a MacArthur Fellow.

<span class="mw-page-title-main">Source control (respiratory disease)</span> Strategy for reducing disease transmission

Source control is a strategy for reducing disease transmission by blocking respiratory secretions produced through breathing, speaking, coughing, sneezing or singing. Multiple source control techniques can be used in hospitals, but for the general public wearing personal protective equipment during epidemics or pandemics, respirators provide the greatest source control, followed by surgical masks, with cloth face masks recommended for use by the public only when there are shortages of both respirators and surgical masks.

William Firth Wells was an American scientist and sanitary engineer. In his early career, he pioneered techniques for the aquaculture of oysters and clams. He is best known for his work on airborne infections. Wells identified that tuberculosis could be transmitted through air via the nuclei of evaporated respiratory droplets, and developed the Wells curve to describe what happens to respiratory droplets after they have been expelled into the air.

<span class="mw-page-title-main">Transmission of COVID-19</span> Mechanisms that spread coronavirus disease 2019

The transmission of COVID-19 is the passing of coronavirus disease 2019 from person to person. COVID-19 is mainly transmitted when people breathe in air contaminated by droplets/aerosols and small airborne particles containing the virus. Infected people exhale those particles as they breathe, talk, cough, sneeze, or sing. Transmission is more likely the closer people are. However, infection can occur over longer distances, particularly indoors.

Droplet nuclei are aerosols formed from the evaporation of respiratory droplets. They are generally smaller than 5 μm in diameter. Droplet nuclei are formed by the "dried residua of larger respiratory droplets". These particles are "the vehicle for airborne respiratory disease transmission, which are the dried-out residual of droplets possibly containing infectious pathogens". Diseases such as tuberculous and COVID-19 can be transmitted via droplet nuclei.

Lidia Morawska is a Polish–Australian physicist and distinguished professor at the School of Earth and Atmospheric Sciences, at the Queensland University of Technology and director of the International Laboratory for Air Quality and Health (ILAQH) at QUT. She is also co-director of the Australia-China Centre for Air Quality Science and Management, an adjunct professor at the Jinan University in China, and a Vice-Chancellor fellow at the Global Centre for Clean Air Research (GCARE), University of Surrey in the United Kingdom. Her work focuses on fundamental and applied research in the interdisciplinary field of air quality and its impact on human health, with a specific focus on atmospheric fine, ultrafine and nanoparticles. Since 2003, she expanded her interests to include also particles from human respiration activities and airborne infection transmission.

The Wells-Riley model is a simple model of the airborne transmission of infectious diseases, developed by William F. Wells and Richard L. Riley for tuberculosis and measles.

Nicole M. Bouvier is an American physician who is Professor of Medicine at Icahn School of Medicine at Mount Sinai. Her research considers the environmental and viral factors that impact respiratory transmission of influenza viruses.

References

  1. ↑ "Transmission-Based Precautions". U.S. Centers for Disease Control and Prevention . 7 January 2016. Retrieved 31 March 2020.
  2. ↑ Siegel JD, Rhinehart E, Jackson M, Chiarello L, Healthcare Infection Control Practices Advisory Committee. "2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings" (PDF). CDC. p. 19. Retrieved 7 February 2019. Airborne transmission occurs by dissemination of either airborne droplet nuclei or small particles in the respirable size range containing infectious agents that remain infective over time and distance
  3. ↑ Tang JW, Marr LC, Li Y, Dancer SJ (April 2021). "Covid-19 has redefined airborne transmission". BMJ. 373: n913. doi: 10.1136/bmj.n913 . PMID   33853842. S2CID   233235666.
  4. 1 2 3 4 5 6 McNeill VF (June 2022). "Airborne Transmission of SARS-CoV-2: Evidence and Implications for Engineering Controls". Annual Review of Chemical and Biomolecular Engineering. 13 (1): 123–140. doi:10.1146/annurev-chembioeng-092220-111631. PMID   35300517. S2CID   247520571.
  5. 1 2 Zhang N, Chen W, Chan PT, Yen HL, Tang JW, Li Y (July 2020). "Close contact behavior in indoor environment and transmission of respiratory infection". Indoor Air. 30 (4): 645–661. Bibcode:2020InAir..30..645Z. doi: 10.1111/ina.12673 . PMID   32259319. S2CID   215408351.
  6. ↑ Pal A, Biswas R, Pal R, Sarkar S, Mukhopadhyay A (1 January 2023). "A novel approach to preventing SARS-CoV-2 transmission in classrooms: A numerical study". Physics of Fluids. 35 (1): 013308. doi:10.1063/5.0131672. ISSN   1070-6631. S2CID   254779734.
  7. ↑ Biswas R, Pal A, Pal R, Sarkar S, Mukhopadhyay A (January 2022). "Risk assessment of COVID infection by respiratory droplets from cough for various ventilation scenarios inside an elevator: An OpenFOAM-based computational fluid dynamics analysis". Physics of Fluids. 34 (1): 013318. arXiv: 2109.12841 . Bibcode:2022PhFl...34a3318B. doi:10.1063/5.0073694. PMC   8939552 . PMID   35340680.
  8. 1 2 3 Staudt A, Saunders J, Pavlin J, Shelton-Davenport M, et al. (Environmental Health Matters Initiative, National Academies of Sciences, Engineering, and Medicine) (22 October 2020). Shelton-Davenport M, Pavlin J, Saunders J, Staudt A (eds.). Airborne Transmission of SARS-CoV-2: Proceedings of a Workshop in Brief. Washington, D.C.: National Academies Press. doi:10.17226/25958. ISBN   978-0-309-68408-8. PMID   33119244. S2CID   236828761.
  9. 1 2 3 Hunziker P (October 2021). "Minimising exposure to respiratory droplets, 'jet riders' and aerosols in air-conditioned hospital rooms by a 'Shield-and-Sink' strategy". BMJ Open. 11 (10): e047772. doi:10.1136/bmjopen-2020-047772. medRxiv   10.1101/2020.12.08.20233056 . PMC   8520596 . PMID   34642190. S2CID   229291099.
  10. ↑ Kesavanathan J, Swift DL (January 1998). "Human Nasal Passage Particle Deposition: The Effect of Particle Size, Flow Rate, and Anatomical Factors". Aerosol Science and Technology. 28 (5): 457–463. Bibcode:1998AerST..28..457K. doi:10.1080/02786829808965537. ISSN   0278-6826.
  11. ↑ Adlish JI, Neuhold P, Surrente R, Tagliapietra LJ (18 June 2021). "RNA Identification and Detection of Nucleic Acids as Aerosols in Air Samples by Means of Photon and Electron Interactions". Instruments. 5 (2): 23. arXiv: 2105.00340 . doi: 10.3390/instruments5020023 .
  12. ↑ "Ack! Sneeze germs carry farther than you think". Chicago Tribune . 19 April 2014.
  13. ↑ "Airborne diseases". Archived from the original on 28 June 2012. Retrieved 21 May 2013.
  14. ↑ "COVID-19: epidemiology, virology and clinical features". GOV.UK. Retrieved 24 October 2020.
  15. ↑ Riley EC, Murphy G, Riley RL (May 1978). "Airborne spread of measles in a suburban elementary school". American Journal of Epidemiology. 107 (5): 421–432. doi:10.1093/oxfordjournals.aje.a112560. PMID   665658.
  16. ↑ "FAQ: Methods of Disease Transmission". Mount Sinai Hospital (Toronto) . Retrieved 31 March 2020.
  17. ↑ La Rosa G, Fratini M, Della Libera S, Iaconelli M, Muscillo M (1 June 2013). "Viral infections acquired indoors through airborne, droplet or contact transmission". Annali dell'Istituto Superiore di Sanità. 49 (2): 124–132. doi:10.4415/ANN_13_02_03. PMID   23771256.
  18. ↑ Tellier R, Li Y, Cowling BJ, Tang JW (January 2019). "Recognition of aerosol transmission of infectious agents: a commentary". BMC Infectious Diseases. 19 (1): 101. doi: 10.1186/s12879-019-3707-y . PMC   6357359 . PMID   30704406.
  19. ↑ Noakes CJ, Beggs CB, Sleigh PA, Kerr KG (October 2006). "Modelling the transmission of airborne infections in enclosed spaces". Epidemiology and Infection. 134 (5): 1082–1091. doi:10.1017/S0950268806005875. PMC   2870476 . PMID   16476170.
  20. ↑ Tang JW, Bahnfleth WP, Bluyssen PM, Buonanno G, Jimenez JL, Kurnitski J, et al. (April 2021). "Dismantling myths on the airborne transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)". The Journal of Hospital Infection. 110: 89–96. doi:10.1016/j.jhin.2020.12.022. PMC   7805396 . PMID   33453351.
  21. ↑ Sze To GN, Chao CY (February 2010). "Review and comparison between the Wells-Riley and dose-response approaches to risk assessment of infectious respiratory diseases". Indoor Air. 20 (1): 2–16. doi:10.1111/j.1600-0668.2009.00621.x. PMC   7202094 . PMID   19874402.
  22. ↑ Mitchell BW, King DJ (October–December 1994). "Effect of negative air ionization on airborne transmission of Newcastle disease virus". Avian Diseases. 38 (4): 725–732. doi:10.2307/1592107. JSTOR   1592107. PMID   7702504.
  23. ↑ Kutter JS, Spronken MI, Fraaij PL, Fouchier RA, Herfst S (February 2018). "Transmission routes of respiratory viruses among humans". Current Opinion in Virology. 28: 142–151. doi:10.1016/j.coviro.2018.01.001. PMC   7102683 . PMID   29452994.
  24. ↑ Seto WH (April 2015). "Airborne transmission and precautions: facts and myths". The Journal of Hospital Infection. 89 (4): 225–228. doi:10.1016/j.jhin.2014.11.005. PMC   7132528 . PMID   25578684.
  25. 1 2 Ma Y, Pei S, Shaman J, Dubrow R, Chen K (June 2021). "Role of meteorological factors in the transmission of SARS-CoV-2 in the United States". Nature Communications. 12 (1): 3602. Bibcode:2021NatCo..12.3602M. doi:10.1038/s41467-021-23866-7. PMC   8203661 . PMID   34127665.
  26. ↑ Božič A, Kanduč M (March 2021). "Relative humidity in droplet and airborne transmission of disease". Journal of Biological Physics. 47 (1): 1–29. doi:10.1007/s10867-020-09562-5. PMC   7872882 . PMID   33564965.
  27. 1 2 Sooryanarain H, Elankumaran S (16 February 2015). "Environmental role in influenza virus outbreaks". Annual Review of Animal Biosciences. 3 (1): 347–373. doi: 10.1146/annurev-animal-022114-111017 . PMID   25422855.
  28. ↑ "Prevention of hospital-acquired infections" (PDF). World Health Organization (WHO).
  29. ↑ Bahl P, Doolan C, de Silva C, Chughtai AA, Bourouiba L, MacIntyre CR (May 2022). "Airborne or Droplet Precautions for Health Workers Treating Coronavirus Disease 2019?". The Journal of Infectious Diseases. 225 (9): 1561–1568. doi:10.1093/infdis/jiaa189. PMC   7184471 . PMID   32301491.
  30. ↑ Noti JD, Blachere FM, McMillen CM, Lindsley WG, Kashon ML, Slaughter DR, Beezhold DH (2013). "High humidity leads to loss of infectious influenza virus from simulated coughs". PLOS ONE. 8 (2): e57485. Bibcode:2013PLoSO...857485N. doi: 10.1371/journal.pone.0057485 . PMC   3583861 . PMID   23460865.
  31. ↑ Pica N, Bouvier NM (February 2012). "Environmental factors affecting the transmission of respiratory viruses". Current Opinion in Virology. 2 (1): 90–95. doi:10.1016/j.coviro.2011.12.003. PMC   3311988 . PMID   22440971.
  32. 1 2 Rodríguez-Rajo FJ, Iglesias I, Jato V (April 2005). "Variation assessment of airborne Alternaria and Cladosporium spores at different bioclimatical conditions". Mycological Research. 109 (Pt 4): 497–507. CiteSeerX   10.1.1.487.177 . doi:10.1017/s0953756204001777. PMID   15912938.
  33. ↑ Peternel R, Culig J, Hrga I (2004). "Atmospheric concentrations of Cladosporium spp. and Alternaria spp. spores in Zagreb (Croatia) and effects of some meteorological factors". Annals of Agricultural and Environmental Medicine. 11 (2): 303–307. PMID   15627341.
  34. ↑ Sabariego S, Díaz de la Guardia C, Alba F (May 2000). "The effect of meteorological factors on the daily variation of airborne fungal spores in Granada (southern Spain)". International Journal of Biometeorology. 44 (1): 1–5. Bibcode:2000IJBm...44....1S. doi:10.1007/s004840050131. PMID   10879421. S2CID   17834418.
  35. 1 2 Hedlund C, Blomstedt Y, Schumann B (2014). "Association of climatic factors with infectious diseases in the Arctic and subarctic region--a systematic review". Global Health Action. 7: 24161. doi:10.3402/gha.v7.24161. PMC   4079933 . PMID   24990685.
  36. ↑ Khan NN, Wilson BL (2003). "An environmental assessment of mold concentrations and potential mycotoxin exposures in the greater Southeast Texas area". Journal of Environmental Science and Health. Part A, Toxic/Hazardous Substances & Environmental Engineering. 38 (12): 2759–2772. Bibcode:2003JESHA..38.2759K. doi:10.1081/ESE-120025829. PMID   14672314. S2CID   6906183.
  37. ↑ Tang JW (December 2009). "The effect of environmental parameters on the survival of airborne infectious agents". Journal of the Royal Society, Interface. 6 (Suppl 6): S737–S746. doi:10.1098/rsif.2009.0227.focus. PMC   2843949 . PMID   19773291.
  38. ↑ "Legionnaire disease" . Retrieved 12 April 2015.
  39. ↑ "Hospital infection control: reducing airborne pathogens - Maintenance and Operations". Healthcare Facilities Today. Retrieved 13 June 2022.
  40. ↑ Zabihi, Mojtaba; Li, Ri; Brinkerhoff, Joshua (1 March 2024). "Influence of indoor airflow on airborne disease transmission in a classroom". Building Simulation. 17 (3): 355–370. doi:10.1007/s12273-023-1097-y. ISSN   1996-8744.
  41. 1 2 American Academy of Orthopaedic Surgeons (AAOS) (2011). Bloodborne and Airborne Pathogens. Jones & Barlett Publishers. p. 2. ISBN   9781449668273 . Retrieved 21 May 2013.
  42. ↑ Clark RP, de Calcina-Goff ML (December 2009). "Some aspects of the airborne transmission of infection". Journal of the Royal Society, Interface. 6 (suppl_6): S767–S782. doi:10.1098/rsif.2009.0236.focus. PMC   2843950 . PMID   19815574.
  43. ↑ "Transmission-Based Precautions | Basics | Infection Control | CDC". www.cdc.gov. 6 February 2020. Retrieved 14 October 2021.
  44. ↑ Ferris M, Ferris R, Workman C, O'Connor E, Enoch DA, Goldesgeyme E, et al. (June 2021). "FFP3 respirators protect healthcare workers against infection with SARS-CoV-2". Authorea Preprints. doi:10.22541/au.162454911.17263721/v1.
  45. ↑ Zabihi, Mojtaba; Li, Ri; Brinkerhoff, Joshua (1 March 2024). "Influence of indoor airflow on airborne disease transmission in a classroom". Building Simulation. 17 (3): 355–370. doi:10.1007/s12273-023-1097-y. ISSN   1996-8744.
  46. 1 2 Conway Morris A, Sharrocks K, Bousfield R, Kermack L, Maes M, Higginson E, et al. (August 2022). "The Removal of Airborne Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Other Microbial Bioaerosols by Air Filtration on Coronavirus Disease 2019 (COVID-19) Surge Units". Clinical Infectious Diseases. 75 (1): e97–e101. doi:10.1093/cid/ciab933. PMC   8689842 . PMID   34718446.
  47. ↑ "Redirect - Vaccines: VPD-VAC/VPD menu page". 7 February 2019.
  48. ↑ Glass RJ, Glass LM, Beyeler WE, Min HJ (November 2006). "Targeted social distancing design for pandemic influenza". Emerging Infectious Diseases. 12 (11): 1671–1681. doi:10.3201/eid1211.060255. PMC   3372334 . PMID   17283616.
  49. ↑ Lai KM, Bottomley C, McNerney R (23 May 2011). "Propagation of respiratory aerosols by the vuvuzela". PLOS ONE. 6 (5): e20086. Bibcode:2011PLoSO...620086L. doi: 10.1371/journal.pone.0020086 . PMC   3100331 . PMID   21629778.
  50. ↑ Wang CC, Prather KA, Sznitman J, Jimenez JL, Lakdawala SS, Tufekci Z, Marr LC (August 2021). "Airborne transmission of respiratory viruses". Science. 373 (6558): eabd9149. doi:10.1126/science.abd9149. PMC   8721651 . PMID   34446582.
  51. ↑ Ziady LE, Small N (2006). Prevent and Control Infection: Application Made Easy. Juta and Company Ltd. pp. 119–120. ISBN   9780702167904.


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