Fomite
A fomite (
Transfer of pathogens by fomites
A fomite is any
Hospital fomites
For humans, common hospital fomites are skin cells, hair, clothing, and bedding.[5]
Fomites are associated particularly with
Basic hospital equipment, such as IV drip tubes, catheters, and life support equipment, can also be carriers, when the pathogens form biofilms on the surfaces. Careful sterilization of such objects prevents cross-infection.[7] Used syringes, if improperly handled, are particularly dangerous fomites.[citation needed]
Daily life
In addition to objects in hospital settings, other common fomites for humans are cups, spoons, pencils, bath faucet handles, toilet flush levers, door knobs, light switches, handrails, elevator buttons, television remote controls, pens, touch screens, common-use phones, keyboards and computer mice, coffeepot handles, countertops, drinking fountains, and any other items that may be frequently touched by different people and infrequently cleaned.[2][8]
Transmission of specific viruses
Researchers have discovered that smooth (non-porous) surfaces like door knobs transmit bacteria and viruses better than porous materials like paper money because porous, especially fibrous, materials absorb and trap the contagion, making it harder to contract through simple touch.[11] Nonetheless, fomites may include soiled clothes, towels, linens, handkerchiefs, and surgical dressings.[12][13]
SARS-CoV-2 was found to be viable on various surfaces from 4 to 72 hours under laboratory conditions. On porous surfaces, studies report inability to detect viable virus within minutes to hours; on non-porous surfaces, viable virus can be detected for days to weeks.[2][14] However, further research called into question the accuracy of such tests, instead finding fomite transmission of SARS-Cov-2 in real world settings is extremely rare if not impossible.[15][16][17][18]
Contact with aerosolized virus (large droplet spread) generated via talking, sneezing, coughing, or vomiting, or contact with airborne virus that settles after disturbance of a contaminated fomite (e.g. shaking a contaminated blanket). During the first 24 hours, the risk can be reduced by increasing ventilation and waiting as long as possible before entering the space (at least several hours, based on documented airborne transmission cases), and using personal protective equipment (including any protection needed for the cleaning and disinfection products) to reduce risk.[2][8]
The 2007 research showed that the influenza virus was still active on stainless steel 24 hours after contamination. Though on hands it survives only for five minutes, the constant contact with a fomite almost certainly means catching the infection.[19] Transfer efficiency depends not only on surface, but mainly on pathogen type. For example, avian influenza survives on both porous and non-porous materials for 144 hours.[11]
Contaminated needles are the most common fomite that transmits HIV.[20] Fomites from dirty needles also easily spread Hepatitis B.[21]
Etymology
The Italian scholar and physician Girolamo Fracastoro appears to have first used the Latin word fomes, meaning "tinder", in this sense in his essay on contagion, De Contagione et Contagiosis Morbis, published in 1546:[22] "By fomes I mean clothes, wooden objects, and things of that sort, which though not themselves corrupted can, nevertheless, preserve the original germs of the contagion and infect by means of these".[23]
English usage of fomes, pronounced /ˈfoʊmiːz/, is documented since 1658.[24] The English word fomite, which has been in use since 1859, is a back-formation from the plural fomites (originally borrowed from the Latin plural fōmĭtēs [ˈfoːmɪteːs] of fōmĕs [ˈfoːmɛs]).[25][26] Over time, the English-language pronunciation of the plural fomites changed from /ˈfoʊmɪtiːz/) to /ˈfoʊmaɪts/, which led to the creation of a new singular fomite, pronounced /ˈfoʊmaɪt/.[26][27][28] The French fomite, Italian fomite, Spanish fómite and Portuguese fómite or fômite, however, are derived directly from the Latin accusative singular fōmĭtĕm, as usually happens with Latin common nouns.[citation needed]
See also
- Focal infection theory
- Focus of infection
- Vector (epidemiology)
References
- ^ a b Cramer, Lorraine (1 September 2011). "Fomites, fomites, fomites!". Microblogology. Archived from the original on 23 September 2020. Retrieved 8 March 2019.
- ^ a b c d "Coronavirus Disease 2019 (COVID-19)". 11 February 2020.
- PMID 33755002.
- ^ "Fomite - an overview | ScienceDirect Topics".
- ^ Bennett, Jarvis & Brachman 2007, p. 275
- PMID 20299125.
[...] in any care activity that involves contact with patients, as [neckties] serve no beneficial function in patient care, are rarely laundered and have been shown to be colonised by pathogens. Coagulase-negative staphylococci (CoNS) were found on two of five neckties of doctors working in an intensive care unit, and Staphylococcus aureus was isolated from eight of 40 doctors' ties in a Scottish hospital.
- ^ Larson & Liverman 2011, pp. 41–42
- ^ PMID 17220247.
- ^ a b Shaw, Michael (27 November 2006). "Never Heard Of Fomites? You'd Better Learn About Them!". gasdetection.com.
- ^ Cook 2013, p. 207
- ^ a b Cook 2013, p. 208
- PMID 7986043.
- S2CID 8477487.
- PMID 32182409.
- S2CID 231765058.
- S2CID 222002135.
- medRxiv 10.1101/2021.08.23.21262477.
- ^ CDC (11 February 2020). "Coronavirus Disease 2019 (COVID-19)". Centers for Disease Control and Prevention. Retrieved 2 February 2022.
- ^ Larson & Liverman 2011, p. 41
- ^ Shors 2017, p. 279
- ^ "Hepatitis B". mayoclinic.org.
- S2CID 37260514.
- ^ Fracastoro, Girolamo (1961). "Contagion, contagious diseases and their treatment (1546)". In Brock, Thomas D. (ed.). Milestones in Microbiology. Translated by Wright, Wilmer C. Prentice-Hall International. pp. 69–75. Retrieved 10 August 2013.
- ^ "fomes". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
- ^ Fortuine 2000, p. 53
- ^ a b "fomite". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
- Merriam-Webster's Online Dictionary. Merriam-Webster. 16 June 2023.
- ^ "Language Log: Fomite: panacea or backformation?". itre.cis.upenn.edu.
Bibliography
- Cook, Nigel (2013), "10.1 Introduction; the role of fomites in the virus transmission", Viruses in Food and Water: Risks, Surveillance and Control, Cambridge: Woodhead Publishing, pp. 205–215, ISBN 978-0-85709-887-0
- Bennett, John V.; Jarvis, William Robert; Brachman, Philip S. (2007), "Chapter 19: The Inanimate Environment", Bennett & Brachman's Hospital Infections, Philadelphia: Lippincott Williams & Wilkins, p. 277, ISBN 978-0-7817-6383-7
- Fortuine, Robert (2000), The Words of Medicine: Sources, Meanings, and Delights, Springfield: Charles C Thomas Publisher, p. 53, ISBN 0398071322
- Larson, Elaine L.; Liverman, Catharyn T. (2011), "Understanding the Risk to Healthcare Personnel: Fomite Persistence", Preventing Transmission of Pandemic Influenza and Other Viral Respiratory Diseases: Personal Protective Equipment for Healthcare Personnel: Update 2010, Washington: National Academies Press, p. 41, ISBN 978-0-309-16254-8
- Shors, Teri (2017), "Clinical Signs and Symptoms of Human Herpersviruses", Understanding Viruses, Wisconsin: Jones & Bartlett Learning, ISBN 978-1-284-02592-7
External links
- General characteristics and roles of fomites in viral transmission, American Society for Microbiology, 1969 Archived 24 April 2010 at the Wayback Machine