Editing Hepatitis C (section)

== Transmission ==
[[File:Hepatitis C infection by source (CDC) - en.svg|thumb|upright=1.4|Hepatitis C infection in the United States by source]]

[[Percutaneous]] contact with contaminated blood is responsible for most infections; however, the method of transmission is strongly dependent on both geographic region and economic status.<ref>{{cite journal | vauthors = Hagan LM, Schinazi RF | title = Best strategies for global HCV eradication | journal = Liver International | volume = 33 | issue = s1 | pages = 68–79 | date = February 2013 | pmid = 23286849 | pmc = 4110680 | doi = 10.1111/liv.12063 | url = }}</ref> Indeed, the primary route of transmission in the [[developed world]] is [[injection drug use]], while in the [[developing world]] the main methods are [[blood transfusions]] and unsafe medical procedures.<ref name=Mah2010 /> The cause of transmission remains unknown in 20% of cases;<ref name=Pon2011>{{cite journal | vauthors = Pondé RA | title = Hidden hazards of HCV transmission | journal = Medical Microbiology and Immunology | volume = 200 | issue = 1 | pages = 7–11 | date = February 2011 | pmid = 20461405 | doi = 10.1007/s00430-010-0159-9 | s2cid = 664199 }}</ref> however, many of these are believed to be accounted for by injection drug use.<ref name=Book2011p4 />

=== Body modification ===
[[Tattooing]] is associated with two- to threefold increased risk of {{nowrap|hepatitis C}}.<ref name=Tato2010>{{cite journal | vauthors = Jafari S, Copes R, Baharlou S, Etminan M, Buxton J | title = Tattooing and the risk of transmission of hepatitis C: a systematic review and meta-analysis | journal = International Journal of Infectious Diseases | volume = 14 | issue = 11 | pages = e928-40 | date = November 2010 | pmid = 20678951 | doi = 10.1016/j.ijid.2010.03.019 | doi-access = free }}</ref> This could be due to improperly sterilized equipment or contamination of the dyes used.<ref name=Tato2010 /> Tattoos or [[Body piercing|piercings]] performed either before the mid-1980s, "underground", or nonprofessionally are of particular concern, since sterile techniques in such settings may be lacking. The risk also appears to be greater for larger tattoos.<ref name=Tato2010 /> It is estimated that nearly half of prison inmates share unsterilized tattooing equipment.<ref name=Tato2010 /> It is rare for tattoos in a licensed facility to be directly associated with HCV infection.<ref>{{cite web|title=Hepatitis C|url=https://www.cdc.gov/hepatitis/HCV/PDFs/HepCGeneralFactSheet.pdf|publisher=Centers for Disease Control and Prevention (CDC)|access-date=2 January 2012|url-status=live|archive-url=https://web.archive.org/web/20120105131937/http://www.cdc.gov/hepatitis/HCV/PDFs/HepCGeneralFactSheet.pdf|archive-date=5 January 2012}}</ref>

=== Drug use ===
[[File:Cocaine lines 2.jpg|thumb|left|Lines of cocaine prepared for snorting. [[Contaminated currency]] such as banknotes might serve as a [[fomite]] of diseases like hepatitis C<ref name="LV">{{cite web |url=http://cocaine.org/cokemoney/banknotes.html |title='Shared banknote' health warning to cocaine users |accessdate=2008-07-26 |author=Laureen Veevers |date=1 October 2006 |work=The Observer }}</ref>]]
{{see also|Needle sharing}}

[[Injection drug use]] (IDU) is a major risk factor for {{nowrap|hepatitis C}} in many parts of the world.<ref name=China2008>{{cite journal | vauthors = Xia X, Luo J, Bai J, Yu R | title = Epidemiology of hepatitis C virus infection among injection drug users in China: systematic review and meta-analysis | journal = Public Health | volume = 122 | issue = 10 | pages = 990–1003 | date = October 2008 | pmid = 18486955 | doi = 10.1016/j.puhe.2008.01.014 }}</ref> Of 77 countries reviewed, 25 (including the United States) were found to have a prevalence of {{nowrap|hepatitis C}} of 60–80% among people who use injection drugs.<ref name=Lancet2011>{{cite journal | vauthors = Nelson PK, Mathers BM, Cowie B, Hagan H, Des Jarlais D, Horyniak D, Degenhardt L | title = Global epidemiology of hepatitis B and hepatitis C in people who inject drugs: results of systematic reviews | journal = Lancet | volume = 378 | issue = 9791 | pages = 571–83 | date = August 2011 | pmid = 21802134 | pmc = 3285467 | doi = 10.1016/S0140-6736(11)61097-0 }}</ref><ref name=China2008 /> Twelve countries had rates greater than 80%.<ref name=Lancet2011 /> It is believed that ten million people who use intravenous drug are infected with {{nowrap|hepatitis C}}; China (1.6 million), the United States (1.5 million), and Russia (1.3 million) have the highest absolute totals.<ref name=Lancet2011 /> [[Infectious diseases within American prisons#Hepatitis C|Occurrence of {{nowrap|hepatitis C}} among prison inmates in the United States]] is 10 to 20 times that of the occurrence observed in the general population; this has been attributed to high-risk behavior in prisons such as IDU and tattooing with non-sterile equipment.<ref name=Jail2010>{{cite journal | vauthors = Imperial JC | title = Chronic hepatitis C in the state prison system: insights into the problems and possible solutions | journal = Expert Review of Gastroenterology & Hepatology | volume = 4 | issue = 3 | pages = 355–64 | date = June 2010 | pmid = 20528122 | doi = 10.1586/egh.10.26 | s2cid = 7931472 }}</ref><ref>{{cite journal | vauthors = Vescio MF, Longo B, Babudieri S, Starnini G, Carbonara S, Rezza G, Monarca R | title = Correlates of hepatitis C virus seropositivity in prison inmates: a meta-analysis | journal = Journal of Epidemiology and Community Health | volume = 62 | issue = 4 | pages = 305–13 | date = April 2008 | pmid = 18339822 | doi = 10.1136/jech.2006.051599 | s2cid = 206989111 }}</ref> Shared intranasal drug use may also be a risk factor.<ref name="Moyer2013"/>

=== Fomites ===
A [[fomite]] ({{IPAc-en|ˈ|f|oʊ|m|aɪ|t}}) or fomes ({{IPAc-en|ˈ|f|oʊ|m|iː|z}}) is any [[inanimate object]] that, when contaminated with or exposed to [[infectious agents]] (such as [[pathogenic bacteria]], [[viruses]] or [[fungi]]), can transfer [[disease]] to a new [[host (biology)|host]].<ref name=Cramer2019>{{Cite web |url=http://microblogology.com/fomites-fomites-fomites/ |title=Fomites, fomites, fomites! |work=Microblogology |last=Cramer |first=Lorraine |date=1 September 2011 |language=en-US |access-date=8 March 2019 |archive-date=23 September 2020 |archive-url=https://web.archive.org/web/20200923101811/http://microblogology.com/fomites-fomites-fomites/ |url-status=dead }}</ref>

Personal-care items such as razors, toothbrushes, and manicuring or pedicuring equipment can be contaminated with blood. Sharing such items can potentially lead to exposure to HCV.<ref name="pmid16907842">{{cite journal | vauthors = Lock G, Dirscherl M, Obermeier F, Gelbmann CM, Hellerbrand C, Knöll A, Schölmerich J, Jilg W | display-authors = 6 | title = Hepatitis C - contamination of toothbrushes: myth or reality? | journal = Journal of Viral Hepatitis | volume = 13 | issue = 9 | pages = 571–3 | date = September 2006 | pmid = 16907842 | doi = 10.1111/j.1365-2893.2006.00735.x | s2cid = 24264376 }}</ref><ref name=CDC12 /> Appropriate caution should be taken regarding any medical condition that results in [[bleeding]], such as cuts and sores.<ref name=CDC12 /> HCV is not spread through casual contact, such as hugging, kissing, or sharing eating or cooking utensils,<ref name=CDC12>{{cite web |url= https://www.cdc.gov/hepatitis/HCV/HCVfaq.htm |title= Hepatitis C FAQs for Health Professionals |publisher= Centers for Disease Control and Prevention (CDC) |access-date= 2 January 2012 |url-status= live |archive-url= https://web.archive.org/web/20120104063744/http://www.cdc.gov/hepatitis/hcv/hcvfaq.htm |archive-date= 4 January 2012 }}</ref> nor is it transmitted through food or water.<ref>{{cite journal | vauthors = Wong T, Lee SS | title = Hepatitis C: a review for primary care physicians | journal = CMAJ | volume = 174 | issue = 5 | pages = 649–59 | date = February 2006 | pmid = 16505462 | pmc = 1389829 | doi = 10.1503/cmaj.1030034 }}</ref>

=== Healthcare exposure ===
[[Blood transfusion]], transfusion of blood products, or [[organ transplants]] without HCV screening carry significant risks of infection.<ref name=AFP2010 /> The United States instituted universal screening in 1992,<ref name=Rosen2011 /> and Canada instituted universal screening in 1990.<ref>{{cite book|vauthors=Day RA, Paul P, Williams B|title=Brunner & Suddarth's textbook of Canadian medical-surgical nursing|date=2009|publisher=Lippincott Williams & Wilkins|location=Philadelphia, PA|isbn=978-0-7817-9989-8|page=1237|url=https://books.google.com/books?id=SB_-CRXvZPYC&pg=PA1237|edition=Canadian 2nd |url-status=live|archive-url=https://web.archive.org/web/20160425134413/https://books.google.com/books?id=SB_-CRXvZPYC&pg=PA1237|archive-date=2016-04-25}}</ref> This decreased the risk from one in 200 units<ref name=Rosen2011>{{cite book|title=Rosen's emergency medicine: concepts and clinical practice | edition = 7th | vauthors = Marx J |year=2010|publisher=Mosby/Elsevier |location=Philadelphia, PA |isbn=978-0-323-05472-0 |page=[https://archive.org/details/rosensemergencym00mdjo/page/n1176 1154] |url=https://archive.org/details/rosensemergencym00mdjo|url-access=limited }}</ref> to between one in 10,000 to one in 10,000,000 per unit of blood.<ref name=Book2011p4 /><ref name=Pon2011 /> This low risk remains as there is a period of about 11–70 days between the potential [[blood donor]]'s acquiring {{nowrap|hepatitis C}} and the blood's testing positive depending on the method.<ref name=Pon2011 /> Some countries do not screen for {{nowrap|hepatitis C}} due to the cost.<ref name=World2007 />

Those who have experienced a [[needle stick injury]] from someone who was HCV positive have about a 1.8% chance of subsequently contracting the disease themselves.<ref name=AFP2010 /> The risk is greater if the needle is hollow and the puncture wound is deep.<ref name=World2007 /> There is a risk from mucosal exposure to blood, but this risk is low, and there is no risk if blood exposure occurs on intact skin.<ref name=World2007 />

Hospital equipment has also been documented as a method of transmission of {{nowrap|hepatitis C}}, including the reuse of needles and syringes, multiple-use medication vials, infusion bags, and improperly sterilized surgical equipment, among others.<ref name=World2007 /> Limitations in the implementation and enforcement of stringent standard precautions in public and private medical and dental facilities are known to have been the primary cause of the spread of HCV in [[Egypt]], the country which had the highest rate of infection in the world in 2012. In 2023, Egypt became the first country to achieve WHO validation on the path to elimination of hepatitis C.<ref>{{cite web|author=WHO Eastern Mediterranean Region|title=Egypt becomes the first country to achieve WHO validation on the path to elimination of hepatitis C|url=https://www.emro.who.int/media/news/egypt-becomes-the-first-country-to-achieve-who-validation-on-the-path-to-elimination-of-hepatitis-c.html|date=9 October 2023|access-date=18 May 2023}}<!-- auto-translated by Module:CS1 translator --></ref>

For further information, see [[HONOReform|HONOReform (Hepatitis Outbreaks National Organization for Reform)]].

=== Mother-to-child transmission ===
[[Mother-to-child transmission]] of {{nowrap|hepatitis C}} occurs in fewer than 10% of pregnancies.<ref name=Preg10>{{cite journal | vauthors = Lam NC, Gotsch PB, Langan RC | title = Caring for pregnant women and newborns with hepatitis B or C | journal = American Family Physician | volume = 82 | issue = 10 | pages = 1225–9 | date = November 2010 | pmid = 21121533 | url = http://www.aafp.org/afp/2010/1115/p1225.pdf | url-status = live | archive-url = https://web.archive.org/web/20130521080102/http://www.aafp.org/afp/2010/1115/p1225.pdf | archive-date = 2013-05-21 }}</ref> There are no measures that alter this risk.<ref name=Preg10 /> It is not clear when transmission occurs during pregnancy, but it may occur both during gestation and at delivery.<ref name=Pon2011 /> A long labor is associated with a greater risk of transmission.<ref name=World2007 /> There is no evidence that [[breastfeeding]] spreads HCV; however, to be cautious, an infected mother is advised to avoid breastfeeding if her nipples are cracked and bleeding,<ref>{{cite book | vauthors = Mast EE |chapter=Mother-to-Infant Hepatitis C Virus Transmission and Breastfeeding |series=Advances in Experimental Medicine and Biology |title=Protecting Infants through Human Milk |volume=554 |pages=211–16|year=2004 |pmid=15384578 |doi=10.1007/978-1-4757-4242-8_18|isbn=978-1-4419-3461-1 }}</ref> or if her viral loads are high.<ref name=Pon2011 />

=== Sexual intercourse ===
Sexual transmission of hepatitis C is uncommon.<ref name=Kim2016/> Studies examining the risk of HCV transmission between [[heterosexual]] partners, when one is infected and the other is not, have found very low risks.<ref name=Kim2016/> Sexual practices that involve higher levels of trauma to the [[anogenital area|anogenital]] mucosa, such as [[anal penetration|anal penetrative sex]], or that occur when there is a concurrent [[sexually transmitted infection]], including [[HIV]] or [[genital ulcer]]ation, present greater risks.<ref name=Kim2016/><ref name=Sex2010>{{cite journal | vauthors = Tohme RA, Holmberg SD | title = Is sexual contact a major mode of hepatitis C virus transmission? | journal = Hepatology | volume = 52 | issue = 4 | pages = 1497–505 | date = October 2010 | pmid = 20635398 | doi = 10.1002/hep.23808 | s2cid = 5592006 | doi-access =  }}</ref> The [[United States Department of Veterans Affairs]] recommends [[condom]] use to prevent {{nowrap|hepatitis C}} transmission in those with multiple partners, but not those in relationships that involve only a single partner.<ref>{{cite web|title=Hepatitis C Group Education Class|url=http://www.hepatitis.va.gov/products/HCV-education-class-script.asp|publisher=United States Department of Veteran Affairs|url-status=dead|archive-url=https://web.archive.org/web/20111109105344/http://www.hepatitis.va.gov/products/HCV-education-class-script.asp|archive-date=2011-11-09|access-date=2011-11-20}}</ref>