Editing Cancer (section)

=== Infection ===
{{Main|Infectious causes of cancer}}
Worldwide, approximately 18% of cancer deaths are related to [[infectious disease]]s.<ref name=Enviro2008/> This proportion ranges from a high of 25% in Africa to less than 10% in the developed world.<ref name=Enviro2008/> Viruses<ref>{{cite journal | vauthors = Moore PS, Chang Y | title = Why do viruses cause cancer? Highlights of the first century of human tumour virology | journal = Nature Reviews. Cancer | volume = 10 | issue = 12 | pages = 878–889 | date = December 2010 | pmid = 21102637 | pmc = 3718018 | doi = 10.1038/nrc2961 | publisher = Springer Science and Business Media LLC }}</ref> are the usual infectious agents that cause cancer but [[bacteria]] and [[parasites]] may also play a role. [[Oncovirus]]es (viruses that can cause human cancer) include:

* [[Human papillomavirus]] ([[cervical cancer]]),
* [[Epstein–Barr virus]] ([[B-cell lymphoproliferative disease]] and [[nasopharyngeal carcinoma]]),
* [[Kaposi's sarcoma herpesvirus]] ([[Kaposi's sarcoma]] and primary effusion lymphomas),
* [[Hepatitis B]] and [[hepatitis C]] viruses ([[hepatocellular carcinoma]])
* [[Human T-cell leukemia virus-1]] (T-cell leukemias).
* [[Merkel cell polyomavirus]] ([[Merkel cell carcinoma]])

Bacterial infection may also increase the risk of cancer, as seen in

* ''[[Helicobacter pylori]]''-induced [[gastric carcinoma]].<ref name="Viral04">{{cite journal |vauthors=Pagano JS, Blaser M, Buendia MA, Damania B, Khalili K, Raab-Traub N, Roizman B |title=Infectious agents and cancer: criteria for a causal relation |journal=Seminars in Cancer Biology |volume=14 |issue=6 |pages=453–71 |date=December 2004 |pmid=15489139 |doi=10.1016/j.semcancer.2004.06.009 }}</ref><ref name="LjubojevicSkerlev2014">{{cite journal |vauthors=Ljubojevic S, Skerlev M |title=HPV-associated diseases |journal=Clinics in Dermatology |volume=32 |issue=2 |pages=227–34 |year=2014 |pmid=24559558 |doi=10.1016/j.clindermatol.2013.08.007}}</ref>
* [[Colibactin]], a [[genotoxin]] associated with ''[[Escherichia coli]]'' infection ([[colorectal cancer]])<ref name=cds/>

Parasitic infections associated with cancer include:

* ''[[Schistosoma haematobium]]'' ([[Bladder cancer|squamous cell carcinoma of the bladder]])
* The [[liver fluke]]s, ''[[Opisthorchis viverrini]]'' and ''[[Clonorchis sinensis]]'' ([[cholangiocarcinoma]]).<ref name="pmid20539059">{{cite journal |vauthors=Samaras V, Rafailidis PI, Mourtzoukou EG, Peppas G, Falagas ME |title=Chronic bacterial and parasitic infections and cancer: a review |journal=Journal of Infection in Developing Countries |volume=4 |issue=5 |pages=267–81 |date=June 2010 |pmid=20539059 |doi=10.3855/jidc.819 |url=http://www.jidc.org/index.php/journal/article/download/20539059/387|url-status=live |archive-url=https://web.archive.org/web/20111004123357/http://www.jidc.org/index.php/journal/article/download/20539059/387 |archive-date=4 October 2011|doi-access=free }}</ref>