Editing Coinfection

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| field           = [[Infectious disease (medical specialty)|Infectious disease]]
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'''Coinfection''' is the simultaneous [[infection]] of a [[host (biology)|host]] by multiple [[pathogens|pathogen]] [[species]]. In [[virology]], coinfection includes simultaneous infection of a single [[cell (biology)|cell]] by two or more [[virus]] particles. An example is the coinfection of [[liver]] cells with [[hepatitis B virus]] and [[hepatitis D virus]], which can arise incrementally by initial infection followed by [[superinfection]].{{cn|date=March 2022}}

Global [[prevalence]] or [[incidence (epidemiology)|incidence]] of coinfection among humans is unknown, but it is thought to be commonplace,<ref>{{cite journal |last1=Cox |first1=FE |title=Concomitant infections, parasites and immune responses |series=122 |journal=Parasitology |volume=Suppl |pages=S23–38 |year=2001 |pmid=11442193 | doi = 10.1017/s003118200001698x |s2cid=150432 |url=https://researchonline.lshtm.ac.uk/17745/1/Concom.pdf }}</ref> sometimes more common than single infection.<ref>{{cite journal |doi=10.1016/S0020-7519(97)00189-6 |last1=Petney |first1=TN |last2=Andrews |first2=RH |title=Multiparasite communities in animals and humans: frequency, structure and pathogenic significance |journal=International Journal for Parasitology |volume=28 |issue=3 |pages=377–93 |year=1998 |pmid=9559357}}</ref>  Coinfection with [[helminths]] affects around 800 million people worldwide.<ref>{{cite journal |doi=10.2307/3285768 |last1=Crompton |first1=DW |title=How much human helminthiasis is there in the world? |journal=The Journal of Parasitology |volume=85 |issue=3 |pages=397–403 |year=1999 |pmid=10386428 |jstor=3285768}}</ref>

Coinfection is of particular human health importance because pathogen species can [[Biological interaction|interact]] within the host. The net effect of coinfection on human health is thought to be negative.<ref>{{cite journal |doi=10.1016/j.jinf.2011.06.005 |last1=Griffiths |first1=EC |last2=Pedersen |first2=ABP |last3=Fenton |first3=A |last4=Petchey |first4=OP |title=The nature and consequences of coinfection in humans |journal=[[Journal of Infection]] |volume=63 |issue=3 |pages=200–206 |year=2011 |pmid= 21704071 |pmc=3430964}}</ref> Interactions can have either [[Ecological facilitation|positive]] or negative effects on other parasites. Under positive parasite interactions, disease [[transmission (medicine)|transmission]] and progression are enhanced and this is also known as [[syndemic|syndemism]]. Negative parasite interactions include microbial interference when one bacterial species suppresses the [[virulence]] or [[colonisation (biology)|colonisation]] of other bacteria, such as ''[[Pseudomonas aeruginosa]]'' suppressing pathogenic ''[[Staphylococcus aureus]]'' [[colony (biology)|colony]] formation.<ref>{{cite journal |last1=Hoffman |first1=L. R. |last2=Deziel |first2=E. |last3=D'argenio |first3=D. A. |last4=Lepine |first4=F. |last5=Emerson |first5=J. |last6=McNamara |first6=S. |last7=Gibson |first7=R. L. |last8=Ramsey |first8=B. W. |last9=Miller |first9=S. I. |title=Selection for Staphylococcus aureus small-colony variants due to growth in the presence of Pseudomonas aeruginosa |journal=Proceedings of the National Academy of Sciences |volume=103 |issue=52 |pages=19890–5 |year=2006 |pmc=1750898 |doi=10.1073/pnas.0606756104 |pmid=17172450 |bibcode=2006PNAS..10319890H |doi-access=free }}</ref> The general patterns of [[Biological interactions|ecological interactions]] between parasite species are unknown, even among common coinfections such as those between [[Sexually transmitted disease|sexually transmitted infections]].<ref>{{cite journal |last1=Shrestha |first1=S. |title=Influence of host genetic and ecological factors in complex concomitant infections – relevance to sexually transmitted infections |journal=Journal of Reproductive Immunology |year=2011 |pmid=22019002 |doi=10.1016/j.jri.2011.09.001 |volume=92 |issue=1–2 |pages=27–32}}</ref> However, [[network theory|network analysis]] of a [[food web]] of coinfection in humans suggests that there is greater potential for interactions via shared food sources than via the [[immune system]].<ref>{{cite journal |last1=Griffiths |first1=E. |last2=Pedersen |first2=A. |last3=Fenton |first3=A. |last4=Petchey |first4=O. |title=Analysis of a summary network of co-infection in humans reveals that parasites interact most via shared resources |journal=Proceedings of the Royal Society B |year=2014 |pmid=24619434 |doi=10.1098/rspb.2013.2286 |volume=281|issue=1782 |pages=20132286 |pmc=3973251}}</ref>

A globally common coinfection involves [[tuberculosis]] and [[HIV]]. In some countries, up to 80% of tuberculosis patients are also HIV-positive.<ref>{{cite web |publisher=[[World Health Organization]] |url=https://www.who.int/hiv/topics/tb/en/index.html |archive-url=https://web.archive.org/web/20060721034510/http://www.who.int/hiv/topics/tb/en/index.html |url-status=dead |archive-date=July 21, 2006 |title=Tuberculosis and HIV}}</ref> The potential for [[Infectious disease dynamics|dynamics]] of these two infectious diseases to be linked has been known for decades.<ref>{{cite journal |last1=Di Perri |first1=G |last2=Cruciani |first2=M |last3=Danzi |first3=MC |last4=Luzzati |first4=R |last5=De Checchi |first5=G |last6=Malena |first6=M |last7=Pizzighella |first7=S |last8=Mazzi |first8=R |last9=Solbiati |first9=M |last10=Concia |first10=E |title=Nosocomial epidemic of active tuberculosis among HIV-infected patients |journal=Lancet |volume=2 |issue=8678–8679 |pages=1502–4 |year=1989 |pmid=2574778|display-authors=8 | doi = 10.1016/s0140-6736(89)92942-5 |s2cid=5608415 }}</ref> Other common examples of coinfections are [[AIDS]], which involves coinfection of end-stage [[HIV]] with opportunistic parasites<ref>{{cite journal |doi=10.1016/j.jinf.2003.09.001 |last1=Lawn |first1=SD |title=AIDS in Africa: the impact of coinfections on the pathogenesis of HIV-1 infection |journal=[[Journal of Infection]] |volume=48 |issue=1 |pages=1–12 |year=2004 |pmid=14667787}}</ref> and polymicrobial infections like [[Lyme disease]] with other diseases.<ref>{{cite journal |last1=Mitchell |first1=PD |last2=Reed |first2=KD |last3=Hofkes |first3=JM |title=Immunoserologic evidence of coinfection with Borrelia burgdorferi, Babesia microti, and human granulocytic Ehrlichia species in residents of Wisconsin and Minnesota |journal=Journal of Clinical Microbiology |volume=34 |issue=3 |pages=724–7 |year=1996 |pmid=8904446 |pmc=228878|doi=10.1128/JCM.34.3.724-727.1996 }}</ref> Coinfections sometimes can epitomize a [[zero sum game]] of bodily resources, and precise viral quantitation demonstrates children co-infected with [[rhinovirus]] and [[respiratory syncytial virus]], [[metapneumovirus]] or [[parainfluenza virus]] have lower nasal viral loads than those with rhinovirus alone.<ref>{{cite journal |last1=Waghmare |first1=A |last2=Strelitz |first2=B |last3=Lacombe |first3=K |last4=Perchetti |first4=GA |last5=Nalla |first5=A |last6=Rha |first6=B |last7=Midgley |first7=C |last8=Lively |first8=JY |last9=Klein |first9=EJ |last10=Kuypers |first10=J |last11=Englund |first11=JA |title=Rhinovirus in Children Presenting to the Emergency Department: Role of Viral Load in Disease Severity and Co-Infections |journal=Open Forum Infectious Diseases |doi=10.1093/ofid/ofz360.2304| pmc=6810026 |volume=6 |issue=10 |pages=S915–S916 |year=2019|doi-access=free }}</ref>

==Poliovirus==

Poliovirus is a [[positive-strand RNA virus|positive single-stranded RNA virus]] in the family ''[[picornavirus|Picornaviridae]]''.    Coinfections appear to be common and several pathways have been identified for transmitting multiple virions to a single host cell.<ref>Aguilera ER, Pfeiffer JK. Strength in numbers: Mechanisms of viral co-infection. Virus Res. 2019;265:43-46. doi:10.1016/j.virusres.2019.03.003</ref>  These include transmission by virion aggregates, transmission of viral [[genome]]s within membrane vesicles, and transmission by [[bacteria]] bound by several viral particles. {{cn|date=July 2021}}

Drake demonstrated that poliovirus is able to undergo multiplicity reactivation.<ref>{{cite journal | vauthors = Drake JW | title = Interference and multiplicity reactivation in polioviruses | journal = Virology | volume = 6 | issue = 1 | pages = 244–64 | date = August 1958 | pmid = 13581529 | doi = 10.1016/0042-6822(58)90073-4 }}</ref>  That is, when polioviruses were irradiated with UV light and allowed to undergo multiple infections of host cells, viable progeny could be formed even at UV doses that inactivated the virus in single infections. Poliovirus can undergo [[genetic recombination]] when at least two viral [[genome]]s are present in the same host cell.  Kirkegaard and Baltimore<ref>{{cite journal | vauthors = Kirkegaard K, Baltimore D | title = The mechanism of RNA recombination in poliovirus | journal = Cell | volume = 47 | issue = 3 | pages = 433–43 | date = November 1986 | pmid = 3021340 | pmc = 7133339 | doi = 10.1016/0092-8674(86)90600-8 }}</ref> presented evidence that [[RNA-dependent RNA polymerase]] (RdRP) catalyzes recombination by a copy choice mechanism in which the RdRP switches between [[positive-sense single-stranded RNA virus|(+)ssRNA]] templates during negative strand synthesis.  Recombination in RNA viruses appears to be an adaptive mechanism for transmitting an undamaged genome to virus progeny.<ref>{{cite journal | vauthors = Barr JN, Fearns R | title = How RNA viruses maintain their genome integrity | journal = The Journal of General Virology | volume = 91 | issue = Pt 6 | pages = 1373–87 | date = June 2010 | pmid = 20335491 | doi = 10.1099/vir.0.020818-0 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Bernstein H, Bernstein C, Michod RE | title = Sex in microbial pathogens | journal = Infection, Genetics and Evolution | volume = 57 | pages = 8–25 | date = January 2018 | pmid = 29111273 | doi = 10.1016/j.meegid.2017.10.024 | doi-access = free | bibcode = 2018InfGE..57....8B }}</ref>

==Examples==
* [[Anaplasmosis#Epidemiology|Anaplasmosis]]
* [[Bacteriophage experimental evolution#Impact of sex/coinfection|Bacteriophage coinfection]]
* [[GB virus C#Human infection|GB virus C]]
* [[HIV-HCV coinfection]]
* [[HIV-TB coinfection]] (enhances TB transmission and lethality)
* [[Hepatitis D]]
* [[Hookworm#Malaria co-infection|Hookworm-malaria coinfection]]
* ''[[Mansonella perstans]]''
* [[Trichuriasis#Signs and symptoms|Trichuriasis]]
* [[Chikungunya]] and [[Dengue]] coinfection
* [[Dengue]] and HIV coinfection (suppresses HIV)
* [[Chagas]] and HIV coinfection
* Most [[sexually transmitted disease]]s and HIV (enhance HIV transmission)
* Some [[COVID-19]] patients, or those who were ill with other [[coronaviruses]], can be co-infected with seasonal [[influenza]] (flu) viral strains, certain viral strains that cause the [[common cold]], or can be co-infected with [[bronchitis]] or [[pneumonia]] from another bacterial or viral micro-organism. Even more dangerous, some of them could already have conditions like [[tuberculosis]] or active [[AIDS]] that make patients very vulnerable.

==See also==
* [[Infectious disease]]
* [[List of human diseases associated with infectious pathogens]]
* [[Superinfection]]
* [[Syndemic]]
* [[Opportunistic infection]]

==References==
{{Reflist}}

== External links ==
{{Medical resources
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|  MeshID         = D060085
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[[Category:Virology]]
[[Category:Epidemiology]]
[[Category:Infectious diseases]]