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swine flu is caused by fucking pigs you disgusting mother fuckers leave pig pussy to the fucking pigs gahhhhh you disgusting fucks
{{about| the swine influenza virus|the 2009 outbreak in humans|2009 swine flu outbreak}}
{{Flu}}
]
] image of the reassorted H1N1 influenza virus photographed at the CDC Influenza Laboratory. The viruses are 80–120&nbsp;]s in diameter.<ref>{{cite web |author= International Committee on Taxonomy of Viruses |title=The Universal Virus Database, version 4: Influenza A |url=http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/00.046.0.01.htm}}</ref>]]


'''Swine influenza''' (also called '''swine flu''', '''hog flu''' and '''pig flu''') refers to ] caused by those strains of ], called '''swine influenza virus''' (SIV), that usually infect (is endemic in) ]s.<ref name=Merck/> As of 2009 these strains are all found in ] and the subtypes of ] known as ], ], ], ], and ]. Swine influenza is common in pigs in the midwestern United States (and occasionally in other states), Mexico, Canada, South America, Europe (including the United Kingdom, Sweden, and Italy), Kenya, Mainland China, Taiwan, Japan and other parts of eastern Asia.<ref name=Merck>{{cite journal
|url=http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121407.htm
|title=Swine influenza|journal=The Merck Veterinary Manual
|date=2008|accessdate=April 30, 2009}}</ref>


Transmission of swine influenza virus from pigs to humans is not common and properly cooked pork poses no risk of infection. When transmitted, the virus does not always cause ] and often the only sign of infection is the presence of ] in the blood, detectable only by laboratory tests. When transmission results in influenza in a human, it is called ] swine flu. People who work with pigs, especially people with intense exposures, are at risk of catching swine flu. However, only about fifty such transmissions have been recorded since the mid-], when identification of influenza subtypes became possible. Rarely, these strains of swine flu can pass from human to human. In humans, the symptoms of swine flu are similar to those of ] and of ] in general, namely ], ], ], ], severe ], ]ing, ] and ].


The ] in humans, known as "swine flu", is due to a new strain of ] that contained genes most closely related to swine influenza.<ref name="Trifonov+2009"/> The origin of this new strain is unknown. However, the ] (OIE) reports that this strain has not been isolated in pigs.<ref name="organisation1">{{cite web
|url=http://www.oie.int/eng/press/en_090427.htm
|title=Press Release: A/H1N1 influenza like human illness in Mexico and the USA: OIE statement
|author=Maria Zampaglione
|publisher=]
|date=April 29, 2009
|accessdate=April 29, 2009
}}</ref> This strain can be transmitted from human to human,<ref> ''World Health Organization'' 27 April 2009</ref> and causes the normal symptoms of influenza.<ref>{{cite web|url=http://www.who.int/csr/disease/swineflu/faq/en/index.html |title=Influenza A(H1N1) frequently asked questions |publisher=Who.int |date= |accessdate=2009-05-07}}</ref>


Pigs can become infected with ], and this appears to have happened during the ] and the ].


== Classification ==
Of the three ] of influenza viruses that cause ], two also cause influenza in pigs, with ] being common in pigs and ] being rare.<ref>{{cite journal
|author=Heinen PP
|url=http://www.vetscite.org/publish/articles/000041/print.html
|title=Swine influenza: a zoonosis
|journal=Veterinary Sciences Tomorrow
|issn=1569-0830
|date=15 September 2003
|quote=Influenza B and C viruses are almost exclusively isolated from man, although influenza C virus has also been isolated from pigs and influenza B has recently been isolated from seals.
}}</ref> ] has not been reported in pigs. Within Influenzavirus A and Influenzavirus C, the strains found in pigs and humans are largely distinct, although due to ] there have been transfers of genes among strains crossing swine, avian, and human species boundaries.


=== Influenza C ===
Influenza C viruses infect both humans and pigs, but do not infect birds.<ref name=Bouvier>{{cite journal |author=Bouvier NM, Palese P |title=The biology of influenza viruses |journal=Vaccine |volume=26 Suppl 4 |pages=D49–53 |year=2008 |month=September |pmid=19230160}}</ref> Transmission between pigs and humans have occurred in the past.<ref>{{cite journal |author=Kimura H, Abiko C, Peng G, ''et al'' |title=Interspecies transmission of influenza C virus between humans and pigs |journal=Virus Res. |volume=48 |issue=1 |pages=71–9 |year=1997 |month=April |pmid=9140195 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0168-1702(96)01427-X}}</ref> For example, influenza C caused small outbreaks of a mild form of influenza amongst children in Japan,<ref name=Matsuzaki>{{cite journal |author=Matsuzaki Y, Sugawara K, Mizuta K, ''et al'' |title=Antigenic and genetic characterization of influenza C viruses which caused two outbreaks in Yamagata City, Japan, in 1996 and 1998 |journal=J. Clin. Microbiol. |volume=40 |issue=2 |pages=422–9 |year=2002 |month=February |pmid=11825952 |pmc=153379 |url=http://jcm.asm.org/cgi/pmidlookup?view=long&pmid=11825952}}</ref> and California.<ref name=Matsuzaki/> Due to its limited host range and the lack of genetic diversity in influenza C, this form of influenza does not cause pandemics in humans.<ref name=Lynch>{{cite journal |author=Lynch JP, Walsh EE |title=Influenza: evolving strategies in treatment and prevention |journal=Semin Respir Crit Care Med |volume=28 |issue=2 |pages=144–58 |year=2007 |month=April |pmid=17458769 |doi=10.1055/s-2007-976487}}</ref>


p.S. wiki pedia does not give accurate info due to it being wrote by morons ty this will be a day that will live in infamy
=== Influenza A ===
Swine influenza is known to be caused by influenza A subtypes ],<ref name = Iowa/> ],<ref name = Iowa>
{{cite web
|url=http://www.vetmed.iastate.edu/departments/vdpam/swine/diseases/chest/swineinfluenza/
|work=Swine Diseases (Chest)
|title=Swine Influenza
|publisher=] College of Veterinary Medicine
}}</ref> ],<ref>
{{cite journal
|author=Shin JY, Song MS, Lee EH, Lee YM, Kim SY, Kim HK, Choi JK, Kim CJ, Webby RJ, Choi YK
|year=2006
|title=Isolation and characterization of novel H3N1 swine influenza viruses from pigs with respiratory diseases in Korea
|journal=Journal of Clinical Microbiology
|volume=44
|issue=11
|pages=3923–7
|doi=10.1128/JCM.00904-06
|pmid=16928961
}}</ref> ],<ref name = Iowa/> and ].<ref>
{{cite journal
|title=Identification of H2N3 influenza A viruses from swine in the United States
|author=Ma W, Vincent AL, Gramer MR, Brockwell CB, Lager KM, Janke BH, Gauger PC, Patnayak DP, Webby RJ, Richt JA
|url=http://www.pnas.org/content/104/52/20949.full
|journal=Proc Nat Acad Sci USA
|doi=10.1073/pnas.0710286104
|volume=104
|issue=52
|pages=20949–54
|pmid=18093945
|pmc=2409247
|date=26 December 2007
}}</ref> In pigs, three influenza A virus subtypes (H1N1, H3N2, and H1N2) are the most common strains worldwide.<ref name=Kothalawala/> In the ], the H1N1 subtype was exclusively prevalent among swine populations before 1998; however, since late August 1998, H3N2 subtypes have been isolated from pigs. As of 2004, H3N2 virus isolates in US swine and turkey stocks were triple ], containing genes from ] (HA, NA, and PB1), swine (NS, NP, and M), and ] (PB2 and PA) lineages.<ref>
{{cite journal
|title=Interspecies and intraspecies transmission of triple reassortant H3N2 influenza A viruses
|author=Yassine HM, Al-Natour MQ, Lee CW, Saif YM
|journal=Virol J
|year=2007
|month=November
|volume=28
|issue=4
|page=129
|pmid=18045494
|pmc=2228287
|doi=10.1186/1743-422X-4-129
}}</ref>

==Surveillance==
{{Expand|date=May 2009}}
Although there is no formal national surveillance system in the United States to determine what viruses are circulating in pigs,<ref name="MMWR5815a5">
{{cite web
|url=http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5815a5.htm
|title=Swine influenza A (H1N1) infection in two children --- Southern California, March--April 2009
|date=22 April 2009
|publisher=]
|work=Morbidity and Mortality Weekly Report
|volume=58 (Dispatch)
|issue=1-3
}}</ref> there is an informal surveillance network in the United States that is part of a world surveillance network.

==History==
Swine influenza was first proposed to be a disease related to human influenza during the 1918 flu pandemic, when pigs became sick at the same time as humans.<ref name=Knobler>{{cite book |editor=Knobler S, Mack A, Mahmoud A, Lemon S |title=The Threat of Pandemic Influenza: Are We Ready? Workshop Summary (2005) |chapter=1: The Story of Influenza |page=75 |chapterurl=http://books.nap.edu/openbook.php?isbn=0309095042&page=75 |publisher=The National Academies Press |location=Washington, D.C.}}</ref> The first identification of an influenza virus as a cause of disease in pigs occurred about ten years later, in 1930.<ref name="pmid12034486" /> For the following 60 years, swine influenza strains were almost exclusively H1N1. Then, between 1997 and 2002, new strains of three different subtypes and five different genotypes emerged as causes of influenza among pigs in North America. In 1997-1998, H3N2 strains emerged. These strains, which include genes derived by ] from human, swine and avian viruses, have become a major cause of swine influenza in North America. Reassortment between H1N1 and H3N2 produced ]. In 1999 in Canada, a strain of ] crossed the species barrier from birds to pigs, but was contained on a single farm.<ref name="pmid12034486">{{cite journal
| author = Olsen CW
| title = The emergence of novel swine influenza viruses in North America
| journal = Virus Research
| volume = 85
| issue = 2
| pages = 199–210
| year = 2002
| month = May
| pmid = 12034486
| doi =
| url = http://linkinghub.elsevier.com/retrieve/pii/S0168170202000278
| issn =
}}</ref>

The H1N1 form of swine flu is one of the descendants of the strain that caused the ].<ref name=NYT76>{{cite news |url=http://select.nytimes.com/gst/abstract.html?res=F10914FA3E5E14768FDDAC0894D1405B868BF1D3&scp=9&sq=Swine+Flu+epidemic&st=p |title=Soft evidence and hard sell |publisher=New York Times |date=5 September 1976}}</ref><ref name=Pandemic/> As well as persisting in pigs, the descendants of the 1918 virus have also circulated in humans through the 20th century, contributing to the normal seasonal epidemics of influenza.<ref name=Pandemic/> However, direct transmission from pigs to humans is rare, with only 12 cases in the U.S. since 2005.<ref>{{cite news |url=http://www.reuters.com/article/latestCrisis/idUSN26488473 |title=U.S. pork groups urge hog farmers to reduce flu risk |agency=Reuters |date=26 April 2009}}</ref> Nevertheless, the retention of influenza strains in pigs after these strains have disappeared from the human population might make pigs a reservoir where influenza viruses could persist, later emerging to reinfect humans once human immunity to these strains has waned.<ref name=Heinen2003>{{Citation
| title = Swine influenza: a zoonosis
| url = http://www.vetscite.org/publish/articles/000041/print.html
| year = 2003
| author = Heinen, P.
| journal = Veterinary Sciences Tomorrow
| pages = 1–11
| accessdate = 2009-05-04
}}</ref>

Swine flu has been reported numerous times as a ] in humans, usually with limited distribution, rarely with a widespread distribution. Outbreaks in swine are common and cause significant economic losses in industry, primarily by causing stunting and extended time to market. For example, this disease costs the ] meat industry about £65 million every year.<ref>{{cite journal |author=Kay RM, Done SH, Paton DJ |title=Effect of sequential porcine reproductive and respiratory syndrome and swine influenza on the growth and performance of finishing pigs |journal=Vet. Rec. |volume=135 |issue=9 |pages=199–204 |year=1994 |month=August |pmid=7998380}}</ref>

=== 1918 pandemic in humans ===
The ] in humans was associated with H1N1 and influenza appearing in pigs,<ref name=Pandemic>
{{cite journal
|author=Taubenberger JK, Morens DM
|journal=Emerg Infect Dis
|year=2006
|url=http://www.cdc.gov/ncidod/eid/vol12no01/05-0979.htm
|pmid=16494711
|title=1918 Influenza: the mother of all pandemics
|volume=12
|issue=1
|pages=15–22
}}</ref> this may reflect a zoonosis either from swine to humans, or from humans to swine. Although it is not certain in which direction the virus was transferred, some evidence suggests that, in this case, pigs caught the disease from humans.<ref name=Knobler/> For instance, swine influenza was only noted as a new disease of pigs in 1918, after the first large outbreaks of influenza amongst people.<ref name=Knobler/> Although a recent ] analysis of more recent strains of influenza in humans, birds, and swine suggests that the 1918 outbreak in humans followed a reassortment event within a mammal,<ref name="pmid18353690">{{cite journal
| author = Vana G, Westover KM
| title = Origin of the 1918 Spanish influenza virus: a comparative genomic analysis
| journal = Molecular Phylogenetics and Evolution
| volume = 47
| issue = 3
| pages = 1100–10
| year = 2008
| month = June
| pmid = 18353690
| doi = 10.1016/j.ympev.2008.02.003
| url =
| issn =
}}</ref> the exact origin of the 1918 strain remains elusive.<ref>{{cite journal |author=Antonovics J, Hood ME, Baker CH |title=Molecular virology: was the 1918 flu avian in origin? |journal=Nature |volume=440 |issue=7088 |pages=E9; discussion E9–10 |year=2006 |month=April |pmid=16641950 |doi=10.1038/nature04824}}</ref>

=== 1976 U.S. outbreak ===<!-- some incoming links anchor here -->
{{main|1976 swine flu outbreak}}
On February 5, 1976, in the United States an army recruit at ] said he felt tired and weak. He died the next day and four of his fellow soldiers were later hospitalized. Two weeks after his death, health officials announced that the cause of death was a new strain of swine flu. The strain, a variant of ], is known as <!-- start -->A/New Jersey/1976 (H1N1)<!-- end -->. It was detected only from January 19 to February 9 and did not spread beyond Fort Dix.<ref name="Gaydos+2006">{{cite journal
| author = Gaydos JC, Top FH, Hodder RA, Russell PK
| title = Swine influenza a outbreak, Fort Dix, New Jersey, 1976
| journal = Emerging Infectious Diseases
| volume = 12
| issue = 1
| pages = 23–8
| year = 2006
| month = January
| pmid = 16494712
| doi =
| url = http://www.cdc.gov/ncidod/EID/vol12no01/05-0965.htm
| issn =
}}</ref>

]
This new strain appeared to be closely related to the strain involved in the 1918 flu pandemic. Moreover, the ensuing increased surveillance uncovered another strain in circulation in the U.S.: ] spread simultaneously, also caused illness, and persisted until March.<ref name="Gaydos+2006"/> Alarmed public-health officials decided action must be taken to head off another major ], and urged President ] that every person in the U.S. be vaccinated for the disease.<ref>{{cite news |first=Harold M. |last=Schmeck |authorlink= |coauthors= |title=Ford Urges Flu Campaign To Inoculate Entire U.S. |url=http://select.nytimes.com/gst/abstract.html?res=F50A17FD3C5A167493C7AB1788D85F428785F9 |work=The New York Times |publisher= |date=March 25, 1976 |accessdate= }}</ref>

The ] program was plagued by delays and public relations problems.<ref>Richard E. Neustadt and Harvey V. Fineberg. (1978). . ''National Academies Press''.</ref> On October 1, 1976, the immunization program began and by October 11, approximately 40 million people, or about 24% of the population, had received swine flu immunizations. That same day, three senior citizens died soon after receiving their swine flu shots and there was a media outcry linking the deaths to the immunizations, despite the lack of positive proof. According to science writer Patrick Di Justo, however, by the time the truth was known — that the deaths were not proven to be related to the vaccine — it was too late. "The government had long feared mass panic about swine flu — now they feared mass panic about the swine flu vaccinations." This became a strong setback to the program.<ref name=DiJusto>, ''Salon.com'', April 28, 2009.</ref>

There were reports of ], a paralyzing ] disorder, affecting some people who had received swine flu immunizations. This syndrome is a rare side-effect of modern influenza vaccines, with an incidence of about one case per million vaccinations.<ref>{{cite journal |author=Vellozzi C, Burwen DR, Dobardzic A, Ball R, Walton K, Haber P |title=Safety of trivalent inactivated influenza vaccines in adults: Background for pandemic influenza vaccine safety monitoring |journal=Vaccine |volume=27 |issue=15 |pages=2114–2120 |year=2009 |month=March |pmid=19356614 |doi=10.1016/j.vaccine.2009.01.125}}</ref> As a result, Di Justo writes that "the public refused to trust a government-operated health program that killed old people and crippled young people." In total, less than 33% of the population had been immunized by the end of 1976. The National Influenza Immunization Program was effectively halted on Dec. 16.

Overall, there were about 500 cases of Guillain-Barré syndrome (GBS), resulting in death from severe pulmonary complications for 25 people, which, according to Dr. P. Haber, were probably caused by an immunopathological reaction to the 1976 vaccine. Other influenza vaccines have not been linked to GBS, though caution is advised for certain individuals, particularly those with a history of GBS.<ref>
{{cite journal
|title=Vaccines and Guillain-Barré syndrome
|author=Haber P, Sejvar J, Mikaeloff Y, Destefano F
|journal=Drug Saf
|year=2009
|volume=32
|issue=4
|pages=309–23
|doi=10.2165/00002018-200932040-00005
|pmid=19388722
|doi_brokendate=2009-04-26
}}</ref><ref>
{{cite web
|title=Influenza / Flu Vaccine
|url=http://www.uis.edu/healthservices/immunizations/influenzavaccine.html
|publisher=University of Illinois at Springfield
|accessdate=26 April 2009
}}</ref> Still, as observed by a participant in the immunization program, the vaccine killed more Americans than the disease did.<ref>BBC: The World; April 28, 2009.</ref>

=== 1988 zoonosis ===
In September 1988, a swine flu virus killed one woman and infected others. 32-year old Barbara Ann Wieners was eight months pregnant when she and her husband, Ed, became ill after visiting the hog barn at a ] in ]. Barbara died eight days later, after developing pneumonia.<ref name="pmid2153372">{{cite journal
| author = McKinney WP, Volkert P, Kaufman J
| title = Fatal swine influenza pneumonia during late pregnancy
| journal = Archives of Internal Medicine
| volume = 150
| issue = 1
| pages = 213–5
| year = 1990
| month = January
| pmid = 2153372
| doi =
| url = http://archinte.ama-assn.org/cgi/pmidlookup?view=long&pmid=2153372
| issn =
}}</ref> The only pathogen identified was an H1N1 strain of swine influenza virus.<ref name="pmid9511782">{{cite journal
| author = Kimura K, Adlakha A, Simon PM
| title = Fatal case of swine influenza virus in an immunocompetent host
| journal = Mayo Clinic Proceedings. Mayo Clinic
| volume = 73
| issue = 3
| pages = 243–5
| year = 1998
| month = March
| pmid = 9511782
| doi =
| url =
| issn =
}}</ref> Doctors were able to induce labor and deliver a healthy daughter before she died. Her husband recovered from his symptoms.

ILI was reportedly widespread among the pigs exhibited at the fair. 76% of 25 swine exhibitors aged 9 to 19 tested positive for antibody to SIV, but no serious illnesses were detected among this group. Additional studies suggested between one and three health care personnel who had contact with the patient developed mild influenza-like illnesses with antibody evidence of swine flu infection. However, there was no community outbreak.<ref>{{cite web|url=http://www.cdc.gov/swineflu/key_facts.htm |title=Key Facts About Swine Flu (CDC) |publisher=Cdc.gov |date= |accessdate=2009-05-07}}</ref><ref name="pmid1845913">{{cite journal
| author = Wells DL, Hopfensperger DJ, Arden NH, Harmon MW, Davis JP, Tipple MA, Schonberger LB
| title = Swine influenza virus infections. Transmission from ill pigs to humans at a Wisconsin agricultural fair and subsequent probable person-to-person transmission
| journal = JAMA : the Journal of the American Medical Association
| volume = 265
| issue = 4
| pages = 478–81
| year = 1991
| pmid = 1845913
| doi =
| url =
| issn =
}}</ref>

===1998 US outbreak in swine===
In 1998, swine flu was found in pigs in four U.S. states. Within a year, it had spread through pig populations across the United States. Scientists found that this virus had originated in pigs as a recombinant form of flu strains from birds and humans. This outbreak confirmed that pigs can serve as a crucible where novel influenza viruses emerge as a result of the reassortment of genes from different strains.<ref>{{cite journal | author=Stephanie Desmon | url=http://www.baltimoresun.com/news/health/bal-swine-flu-strain0428,0,3165467.story | title=Expert: Swine flu virus more complex than typically seen | journal=Baltimore Sun | date=April 28, 2009}}</ref><ref>{{cite web|url=http://www.newscientist.com/blogs/shortsharpscience/2009/04/why-the-pork-industry-hates-th.html |title=Pork industry is blurring the science of swine flu - Short Sharp Science |publisher=New Scientist |date= |accessdate=2009-05-07}}</ref><ref>{{cite web|url=http://www.newscientist.com/article/mg20227063.800-swine-flu-the-predictable-pandemic.html?full=true |title=Swine flu: The predictable pandemic? - 29 April 2009 |publisher=New Scientist |date= |accessdate=2009-05-07}}</ref>

=== 2007 Philippine outbreak in swine ===
{{Expand|date=April 2009}}<!-- explain connection (if any) between swine flu outbreak and hog cholera -->
On August 20, 2007 Department of Agriculture<!--Unclear.. Does this mean the Philippines Dept of Agriculture or some other country? --> officers investigated the outbreak (]) of swine flu in ] and Central ], ]. The mortality rate is less than 10% for swine flu, unless there are complications like ]. On July 27, 2007, the ] National Meat Inspection Service (NMIS) raised a hog cholera "''red alert''" warning over ] and 5 regions of Luzon after the disease spread to backyard pig farms in ] and ], even if these tested negative for the swine flu virus.<ref>
{{cite news
|url=http://www.gmanews.tv/story/56805/DA-probes-reported-swine-flu-outbreak-in-N-Ecija
|title=DA probes reported swine flu 'outbreak' in N. Ecija
|publisher=Gmanews.tv
|date=
|accessdate=2009-04-25
}}</ref><ref>
{{cite news
|url=http://www.gmanews.tv/story/53014/Govt-declares-hog-cholera-alert-in-Luzon
|title=Gov't declares hog cholera alert in Luzon
|publisher=Gmanews.tv
|date=
|accessdate=2009-04-25
}}</ref>

===2009 outbreak in humans===
{{main|2009 swine flu outbreak}}
The 2009 flu outbreak is due to a new strain of subtype H1N1 not previously reported in pigs.<ref name="organisation1"/> Following the outbreak, on May 2, 2009, it was reported in pigs at a farm in ], ], with a link to the ]. The pigs are suspected to have caught this new strain of virus from a farm worker who recently returned from Mexico, then showed symptoms of an influenza-like illness.<ref>{{cite news | first= | last= | coauthors= |authorlink= | title=An Alberta Swine Herd Investigated for H1N1 Flu Virus | date=May 2, 2009 | publisher=The Canadian Food Inspection Agency | url =http://www.inspection.gc.ca/english/corpaffr/newcom/2009/20090502e.shtml | work = | pages = | accessdate = 2009-05-03 | language = }}</ref> These are probable cases, pending confirmation by laboratory testing.

The new strain was initially described as apparent ] of at least four strains of ], including one strain ], one ], and two endemic in swine.<ref name="NewSci-20090424-pandemic">{{cite news|url=http://www.newscientist.com/article/dn17025-deadly-new-flu-virus-in-us-and-mexico-may-go-pandemic.html|title=Deadly new flu virus in US and Mexico may go pandemic|work=]|date=2009-04-24|accessdate=2009-04-26}}</ref> Subsequent analysis suggested it was a reassortment of just two strains, both found in swine.<ref name="Trifonov+2009">{{cite journal
|journal= Eurosurveillance
|volume=4
|issue=17
|date=30 April 2009
|title=The origin of the recent swine influenza A(H1N1) virus infecting humans
|author=V Trifonov, H Khiabanian, B Greenbaum, R Rabadan
|url=http://www.eurosurveillance.org/images/dynamic/EE/V14N17/art19193.pdf
}}</ref> Although initial reports identified the new strain as swine influenza (ie, a ] originating in swine), its origin is unknown. Several countries took precautionary measures to reduce the chances for a global pandemic of the disease.<ref>{{cite web |url=http://news.yahoo.com/s/ap/20090430/ap_on_he_me/eu_swine_flu_drastic_measures |title=World takes drastic steps to contain swine flu |date=30 April 2009}}</ref>

== Transmission ==
=== Transmission between pigs ===
Influenza is quite common in pigs, with about half of breeding pigs having been exposed to the virus in the US.<ref name=cfsph/> Antibodies to the virus are also common in pigs in other countries.<ref name=cfsph/>

The main route of transmission is through direct contact between infected and uninfected animals.<ref name=Kothalawala/> These close contacts are particularly common during animal transport. ] may also increase the risk of transmission, as the pigs are raised in very close proximity to each other.<ref>{{cite journal |author=Gilchrist MJ, Greko C, Wallinga DB, Beran GW, Riley DG, Thorne PS |title=The potential role of concentrated animal feeding text'''''''''Bold text''''''''' operations in infectious disease epidemics and antibiotic resistance |journal=Environ. Health Perspect. |volume=115 |issue=2 |pages=313–6 |year=2007 |month=February |pmid=17384785 |pmc=1817683 |doi=10.1289/ehp.8837}}</ref><ref>{{cite journal |author=Saenz RA, Hethcote HW, Gray GC |title=Confined animal feeding operations as amplifiers of influenza |journal=Vector Borne Zoonotic Dis. |volume=6 |issue=4 |pages=338–46 |year=2006 |pmid=17187567 |pmc=2042988 |doi=10.1089/vbz.2006.6.338}}</ref> The direct transfer of the virus probably occurs either by pigs touching noses, or through dried mucus. Airborne transmission through the aerosols produced by pigs coughing or sneezing are also an important means of infection.<ref name=Kothalawala/> The virus usually spreads quickly through a herd, infecting all the pigs within just a few days.<ref name=Merck/> Transmission may also occur through wild animals, such as ], which can spread the disease between farms.<ref>{{Citation | title = Antibodies to selected viral and bacterial pathogens in European wild boars from southcentral Spain | url = http://www.jwildlifedis.org/cgi/reprint/38/3/649.pdf | year = 2002 | journal = Journal of wildlife diseases | page = 649 | volume = 38 | issue = 3 | last1 = Vicente | first1 = J. | last2 = Leon-vizcaino | first2 = L. | last3 =Gortazar | first3 = C. | last4 =Jose Cubero | first4 =M. | last5 = Gonzalez | first5 = M. | last6 = Martin-atance | first6 = P. | accessdate = 2009-05-02}}</ref>

=== Transmission to humans ===
People who work with poultry and swine, especially people with intense exposures, are at increased risk of ] infection with influenza virus endemic in these animals, and constitute a population of human hosts in which ] and ] can co-occur.<ref name="pmid19276439">{{cite journal
| author = Gray GC, Kayali G
| title = Facing pandemic influenza threats: the importance of including poultry and swine workers in preparedness plans
| journal = Poultry Science
| volume = 88
| issue = 4
| pages = 880–4
| year = 2009
| month = April
| pmid = 19276439
| doi = 10.3382/ps.2008-00335
| url =
| issn =
}}</ref> Vaccination of these workers against influenza and surveillance for new influenza strains among this population may therefore be an important public health measure.<ref>{{cite journal |author=Gray GC, Trampel DW, Roth JA |title=Pandemic influenza planning: shouldn't swine and poultry workers be included? |journal=Vaccine |volume=25 |issue=22 |pages=4376–81 |year=2007 |month=May |pmid=17459539 |pmc=1939697 |doi=10.1016/j.vaccine.2007.03.036}}</ref> Transmission of influenza from swine to humans who work with swine was documented in a small surveillance study performed in 2004 at the University of Iowa.<ref name="pmid18258038">{{cite journal
| author = Gray GC, McCarthy T, Capuano AW, Setterquist SF, Olsen CW, Alavanja MC
| title = Swine workers and swine influenza virus infections
| journal = Emerging Infectious Diseases
| volume = 13
| issue = 12
| pages = 1871–8
| year = 2007
| month = December
| pmid = 18258038
| doi =
| url = http://www.cdc.gov/eid/content/13/12/1871.htm
| issn =
}}</ref> This study among others forms the basis of a recommendation that people whose jobs involve handling poultry and swine be the focus of increased public health surveillance.<ref name="pmid19276439"/> Other professions at particular risk of infection are veterinarians and meat processing workers, although the risk of infection for both of these groups is lower than that of farm workers.<ref>{{cite journal |author=Myers KP, Olsen CW, Setterquist SF, ''et al'' |title=Are swine workers in the United States at increased risk of infection with zoonotic influenza virus? |journal=Clin. Infect. Dis. |volume=42 |issue=1 |pages=14–20 |year=2006 |month=January |pmid=16323086 |pmc=1673212 |doi=10.1086/498977}}</ref>

=== Interaction with avian H5N1 in pigs ===
Pigs are unusual as they can be infected with influenza strains that usually infect three different species: pigs, birds and humans.<ref name=Thacker>{{cite journal |author=Thacker E, Janke B |title=Swine influenza virus: zoonotic potential and vaccination strategies for the control of avian and swine influenzas |journal=J. Infect. Dis. |volume=197 Suppl 1 |issue= |pages=S19–24 |year=2008 |month=February |pmid=18269323 |doi=10.1086/524988}}</ref> This makes pigs a host where influenza viruses might exchange genes, producing new and dangerous strains.<ref name=Thacker/> Avian influenza virus ] is ] in ]s in ] and has been detected in pigs in ], increasing fears of the emergence of new variant strains.<ref>{{cite journal
|url=http://jcm.asm.org/cgi/content/full/46/3/1067?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=phylogenetic&searchid=1&FIRSTINDEX=230&resourcetype=HWFIG
|title=Genetic evolution of swine influenza A (H3N2) viruses in China from 1970 to 2006
|journal=Journal of Clinical Microbiology
|volume=46
|issue=3
|page=1067
|year=2008
|month=March
|doi=10.1128/JCM.01257-07
|author=Yu, H.
|pmid=18199784
}}</ref> ] evolved from ] by ].<ref>{{cite journal
|title=Genetic analysis of human H2N2 and early H3N2 influenza viruses, 1957–1972: evidence for genetic divergence and multiple reassortment events
|author=Lindstrom Stephen E, Cox Nancy J, Klimov Alexander
|journal=Virology
|volume=328
|issue=1
|date=15 October 2004
|pages=101–19
|doi=10.1016/j.virol.2004.06.009
|pmid=15380362
}}</ref> In August 2004, researchers in ] found ] in pigs.<ref name="timeline">
{{cite web
|url=http://www.who.int/csr/disease/avian_influenza/Timeline_28_10a.pdf
|format=PDF
|title=H5N1 avian influenza: timeline
|author=World Health Organization
|date=28 October 2005
}}</ref>
]
These H5N1 infections may be quite common: in a survey of 10 apparently healthy pigs housed near poultry farms in ], where avian flu had broken out, five of the pig samples contained the H5N1 virus. The Indonesian government has since found similar results in the same region. Additional tests of 150 pigs outside the area were negative.<ref>{{cite news
|url=http://www.cidrap.umn.edu/cidrap/content/influenza/avianflu/news/may2705avflu.html
|publisher=Center for Infectious Disease Research & Policy
|place=University of Minnesota
|title=Indonesian pigs have avian flu virus; bird cases double in China
|date=27 May 2005
|accessdate=2009-04-26
}}</ref><ref>{{cite news
|editor=Roos Robert
|url=http://www.cidrap.umn.edu/cidrap/content/influenza/avianflu/news/mar3109swine-jw.html
|title=H5N1 virus may be adapting to pigs in Indonesia
|publisher=Center for Infectious Disease Research & Policy
|place=University of Minnesota
|date=31 March 2009
|accessdate=2009-04-26
}} report on pigs as carriers.</ref>

== Signs and symptoms ==
===In swine===
In pigs influenza infection produces fever, lethargy, sneezing, coughing, difficulty breathing and decreased appetite.<ref name=Kothalawala>{{cite journal |author=Kothalawala H, Toussaint MJ, Gruys E |title=An overview of swine influenza |journal=Vet Q |volume=28 |issue=2 |pages=46–53 |year=2006 |month=June |pmid=16841566}}</ref> In some cases the infection can cause abortion. Although mortality is usually low (around 1-4%),<ref name=Merck/> the virus can produce weight loss and poor growth, causing economic loss to farmers.<ref name=Kothalawala/> Infected pigs can lose up to 12&nbsp;pounds of body weight over a 3 to 4 week period.<ref name=Kothalawala/>

===In humans===
]

Direct transmission of a swine flu virus from pigs to humans is occasionally possible (called ] swine flu). In all, 50 cases are known to have occurred since the first report in medical literature in 1958, which have resulted in a total of six deaths.<ref name=Myers>{{cite journal |author=Myers KP, Olsen CW, Gray GC |title=Cases of swine influenza in humans: a review of the literature |journal=Clin. Infect. Dis. |volume=44 |issue=8 |pages=1084–8 |year=2007 |month=April |pmid=17366454 |pmc=1973337 |doi=10.1086/512813 |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=17366454}}</ref> Of these six people, one was pregnant, one had ], one had ] and two were known to be previously healthy.<ref name=Myers/> Despite these apparently low numbers of infections, the true rate of infection may be higher, since most cases only cause a very mild disease, and will probably never be reported or diagnosed.<ref name=Myers/>
]]

According to the ] (CDC), in humans the symptoms of the 2009 "swine flu" H1N1 virus are similar to those of ] and of ] in general. Symptoms include fever, cough, sore throat, body aches, headache, chills and fatigue. The 2009 outbreak has shown an increased percentage of patients reporting diarrhea and vomiting.<ref>{{cite web
|url=http://www.cdc.gov/swineflu/swineflu_you.htm
|title=Swine Flu and You
|publisher=]
|date=2009-04-26
|accessdate=2009-04-26
}}</ref> The 2009 H1N1 virus is not zoonotic swine flu, as it is not transmitted from pigs to humans, but from person to person.

Because these symptoms are not specific to swine flu, a ] of ''probable'' swine flu requires not only symptoms but also a high likelihood of swine flu due to the person's recent history. For example, during the ], CDC advised physicians to "consider swine influenza infection in the differential diagnosis of patients with acute febrile respiratory illness who have either been in contact with persons with confirmed swine flu, or who were in one of the five U.S. states that have reported swine flu cases or in Mexico during the 7 days preceding their illness onset."<ref name=CDCguideHD>{{cite web
|title=CDC Health Update: Swine Influenza A (H1N1) Update: New Interim Recommendations and Guidance for Health Directors about Strategic National Stockpile Materiel
|author=Centers for Disease Control and Prevention
|publisher=Health Alert Network
|date=April 26, 2009
|url=http://www.cdc.gov/swineflu/HAN/042609.htm
|accessdate=April 27, 2009
}}</ref> A diagnosis of ''confirmed'' swine flu requires laboratory testing of a respiratory sample (a simple nose and throat swab).<ref name=CDCguideHD/>

== Prevention ==
Prevention of swine influenza has three components: prevention in swine, prevention of transmission to humans, and prevention of its spread among humans.

=== Prevention in swine ===
Methods of preventing the spread of influenza among swine include facility management, herd management, and vaccination. Because much of the illness and death associated with swine flu involves secondary infection by other pathogens, control strategies that rely on vaccination may be insufficient.

Control of swine influenza by vaccination has become more difficult in recent decades, as the ] of the ] has resulted in inconsistent responses to traditional vaccines. Standard commercial swine flu vaccines are effective in controlling the infection when the virus strains match enough to have significant cross-protection, and custom (autogenous) vaccines made from the specific viruses isolated are created and used in the more difficult cases.<ref>
{{cite web
|url=http://nationalhogfarmer.com/mag/swine_flu_virus_endemic/
|publisher=National Hog Farmer
|title=Swine flu virus turns endemic
|date=15 September 2007
}}</ref><ref>{{cite web
|url=http://www.livestock.novartis.com/cv_swine.html
|publisher=Novartis
|work=Custom Vaccines
|title=Swine
}}</ref> Present ] strategies for SIV control and prevention in swine farms typically include the use of one of several bivalent SIV vaccines commercially available in the United States. Of the 97 recent H3N2 isolates examined, only 41 isolates had strong serologic cross-reactions with antiserum to three commercial SIV vaccines. Since the protective ability of influenza vaccines depends primarily on the closeness of the match between the vaccine virus and the epidemic virus, the presence of nonreactive H3N2 SIV variants suggests that current commercial vaccines might not effectively protect pigs from infection with a majority of H3N2 viruses.<ref>{{cite journal
|url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1899866
|journal=Canadian Journal of Veterinary Research
|date=July 2007
|volume=71
|issue=3
|pages=201–206
|title=Serologic and genetic characterization of North American H3N2 swine influenza A viruses
|author=Gramer Marie René, Lee Jee Hoon, Choi Young Ki, Goyal Sagar M, Joo Han Soo
|pmid=1899866
|doi=
}}</ref><ref name="pmid17366454">
{{cite journal
|author=Myers KP, Olsen CW, Gray GC |title=Cases of swine influenza in humans: a review of the literature
|journal=Clin Infect Dis
|volume=44
|issue=8
|pages=1084–8
|year=2007
|month=April
|pmid=17366454
|pmc=1973337
|doi=10.1086/512813
}}</ref> The United States Department of Agriculture researchers say that while pig vaccination keeps pigs from getting sick, it does not block infection or shedding of the virus.<ref>{{cite web|url=http://www.newscientist.com/article/mg20227063.800-swine-flu-the-predictable-pandemic.html?full=true/|title=Swine flu: The predictable pandemic?|date=2009-04-29}}</ref>

Facility management includes using disinfectants and ambient temperature to control virus in the environment. The virus is unlikely to survive outside living cells for more than two weeks, except in cold (but above freezing) conditions, and it is readily inactivated by disinfectants.<ref name=Merck/> Herd management includes not adding pigs carrying influenza to herds that have not been exposed to the virus. The virus survives in healthy carrier pigs for up to 3 months and can be recovered from them between outbreaks. Carrier pigs are usually responsible for the introduction of SIV into previously uninfected herds and countries, so new animals should be ]d.<ref name=cfsph/> After an outbreak, as immunity in exposed pigs wanes, new outbreaks of the same strain can occur.<ref name=Merck/>

===Prevention in humans===
;Prevention of pig to human transmission
]s can occur that create new influenza strains.]]
The transmission from swine to human is believed to occur mainly in swine farms where farmers are in close contact with live pigs. Although strains of swine influenza are usually not able to infect humans this may occasionally happen, so farmers and veterinarians are encouraged to use a face mask when dealing with infected animals. The use of vaccines on swine to prevent their infection is a major method of limiting swine to human transmission. Risk factors that may contribute to swine-to-human transmission include smoking and not wearing gloves when working with sick animals.<ref>{{cite journal |author=Ramirez A, Capuano AW, Wellman DA, Lesher KA, Setterquist SF, Gray GC |title=Preventing zoonotic influenza virus infection |journal=Emerging Infect. Dis. |volume=12 |issue=6 |pages=996–1000 |year=2006 |month=June |pmid=16707061 |pmc=1673213 |doi= |url=http://www.cdc.gov/ncidod/eid/vol12no06/05-1576.htm}}</ref>

;Prevention of human to human transmission
Influenza spreads between humans through coughing or sneezing and people touching something with the virus on it and then touching their own nose or mouth.<ref name=CDCspread>
{{cite web
|url=http://www.cdc.gov/swineflu/key_facts.htm
|title=Q & A: Key facts about swine influenza (swine flu) – Spread of Swine Flu
|publisher=Centers for Disease Control and Prevention
|date=24 April 2009
|accessdate=2009-04-26
}}</ref> Swine flu cannot be spread by pork products, since the virus is not transmitted through food.<ref name=CDCspread/> The swine flu in humans is most contagious during the first five days of the illness although some people, most commonly children, can remain contagious for up to ten days. Diagnosis can be made by sending a specimen, collected during the first five days for analysis.<ref>
{{cite web
|url=http://www.cdc.gov/swineflu/key_facts.htm
|title=Q & A: Key facts about swine influenza (swine flu) – Diagnosis
|publisher=Centers for Disease Control and Prevention
|date=24 April 2009
|accessdate=2009-04-26
}}</ref>

Recommendations to prevent spread of the virus among humans include using standard ]. This includes frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public.<ref>{{cite web|url=http://cdc.gov/swineflu/investigation.htm|title=CDC - Influenza (Flu) &#124; Swine Influenza (Flu) Investigation|publisher=Cdc.gov|date=|accessdate=2009-04-27}}</ref> Chance of transmission is also reduced by disinfecting household surfaces, which can be done effectively with a diluted chlorine bleach solution.<ref>{{cite web |url=http://www.waterandhealth.org/newsletter/new/winter_2005/chlorine_bleach.html
|title=Chlorine Bleach: Helping to Manage the Flu Risk
|publisher=Water Quality & Health Council
|date=April 2009
|accessdate=2009-05-12
}}</ref> Although the current trivalent influenza vaccine is unlikely to provide protection against the new 2009 H1N1 strain,<ref>{{cite web
|url=http://www.cdc.gov/swineflu/key_facts.htm
|title=Q & A: Key facts about swine influenza (swine flu) – Virus Strains
|publisher=Centers for Disease Control and Prevention
|date=24 April 2009
|accessdate=2009-04-26
}}</ref> vaccines against the new strain are being developed and could be ready as early as June 2009.<ref>{{cite news
|url=http://www.nbcconnecticut.com/news/local/CT-Company-Making-Swine-Flu-Vaccine.html
|title=Swine Flu Vaccine Could Be Ready in 6 Weeks
|publisher=NBC Connecticut
|author=Lauren Petty
|date=April 28, 2009
|accessdate=April 28, 2009
}}</ref>

Experts agree that hand-washing can help prevent viral infections, including ordinary influenza and the swine flu virus. Influenza can spread in coughs or sneezes, but an increasing body of evidence shows small droplets containing the virus can linger on tabletops, telephones and other surfaces and be transferred via the fingers to the mouth, nose or eyes. Alcohol-based gel or foam hand sanitizers work well to destroy viruses and bacteria. Anyone with flu-like symptoms such as a sudden fever, cough or muscle aches should stay away from work or public transportation and should contact a doctor to be tested.

] is another tactic. It means staying away from other people who might be infected and can include avoiding large gatherings, spreading out a little at work, or perhaps staying home and lying low if an infection is spreading in a community. ] and other responsible authorities have action plans which may request or require social distancing actions depending on the severity of the outbreak.

== Treatment ==
===In swine===
As swine influenza is rarely fatal to pigs, little treatment beyond rest and supportive care is required.<ref name=cfsph>{{cite web |url=http://www.cfsph.iastate.edu/Factsheets/pdfs/influenza.pdf |title=Influenza Factsheet |publisher=Center for Food Security and Public Health, Iowa State University}}</ref> Instead veterinary efforts are focused on preventing the spread of the virus throughout the farm, or to other farms.<ref name=Kothalawala/> Vaccination and animal management techniques are most important in these efforts. Antibiotics are also used to treat this disease, which although they have no effect against the influenza virus, do help prevent bacterial ] and other ]s in influenza-weakened herds.<ref name="cfsph"/>

===In humans===
If a person becomes sick with swine flu, antiviral drugs can make the illness milder and make the patient feel better faster. They may also prevent serious flu complications. For treatment, antiviral drugs work best if started soon after getting sick (within 2 days of symptoms). Beside antivirals, ], at home or in hospital, focuses on controlling fevers and maintaining fluid balance. The U.S. ] recommends the use of Tamiflu (]) or Relenza (]) for the treatment and/or prevention of infection with swine influenza viruses, however, the majority of people infected with the virus make a full recovery without requiring medical attention or antiviral drugs.<ref>{{cite web|url=http://www.who.int/csr/disease/swineflu/faq/en/index.html|title=www.who.int/csr/disease/swineflu/faq/en/index.html<!--INSERT TITLE-->}}</ref> The virus isolates in the 2009 outbreak have been found resistant to ] and ].<ref>{{cite web |url=http://www.cdc.gov/swineflu/antiviral_swine.htm |title=Antiviral Drugs and Swine Influenza |publisher=Centers for Disease Control |accessdate=2009-04-27}}</ref>

In the U.S., on April 27, 2009, the ] issued ]s to make available ] and ] ]s to treat the swine influenza virus in cases for which they are currently unapproved. The agency issued these EUAs to allow treatment of patients younger than the current approval allows and to allow the widespread distribution of the drugs, including by non-licensed volunteers.<ref>{{cite web|url=http://www.fda.gov/bbs/topics/NEWS/2009/NEW02002.html |title='&#39;FDA Authorizes Emergency Use of Influenza Medicines, Diagnostic Test in Response to Swine Flu Outbreak in Humans.'&#39; FDA News, April 27, 2009 |publisher=Fda.gov |date=2009-04-27 |accessdate=2009-05-07}}</ref>

==See also==
{{commonscat|Swine flu}}
{{wikinews|Category:Swine flu|Swine flu}}
*]
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==Notes==
{{reflist|2}}

== Further reading ==
* {{cite journal |author=Alexander DJ |title=Ecological aspects of influenza A viruses in animals and their relationship to human influenza: a review |journal=J R Soc Med |volume=75 |issue=10 |pages=799–811 |year=1982 |month=October |pmid=6752410 |pmc=1438138 |doi= |url=}}
* {{cite journal |author=Hampson AW, Mackenzie JS |title=The influenza viruses |journal=Med. J. Aust. |volume=185 |issue=10 Suppl |pages=S39–43 |year=2006 |month=November |pmid=17115950 |doi= |url=http://www.mja.com.au/public/issues/185_10_201106/ham10884_fm.html}}
* {{cite journal |author=Lipatov AS, Govorkova EA, Webby RJ, ''et al'' |title=Influenza: emergence and control |journal=J. Virol. |volume=78 |issue=17 |pages=8951–9 |year=2004 |month=September |pmid=15308692 |pmc=506949 |doi=10.1128/JVI.78.17.8951-8959.2004 |url=}}
* {{cite journal |author=Van Reeth K |title=Avian and swine influenza viruses: our current understanding of the zoonotic risk |journal=Vet. Res. |volume=38 |issue=2 |pages=243–60 |year=2007 |pmid=17257572 |doi=10.1051/vetres:2006062 |url=}}
* {{cite journal |author=Webster RG, Bean WJ, Gorman OT, Chambers TM, Kawaoka Y |title=Evolution and ecology of influenza A viruses |journal=Microbiol. Rev. |volume=56 |issue=1 |pages=152–79 |year=1992 |month=March |pmid=1579108 |pmc=372859 |doi= |url=http://mmbr.asm.org/cgi/pmidlookup?view=long&pmid=1579108}}
* {{cite journal |author=Winkler WG |title=Influenza in animals: its possible public health significance |journal=J. Wildl. Dis. |volume=6 |issue=4 |pages=239–42; discussion 247–8 |year=1970 |month=October |pmid=16512120 |doi= |url=http://www.jwildlifedis.org/cgi/pmidlookup?view=long&pmid=16512120}}

== External links ==
* on ]
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* (NHS Direct)

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Revision as of 20:45, 13 May 2009

swine flu is caused by fucking pigs you disgusting mother fuckers leave pig pussy to the fucking pigs gahhhhh you disgusting fucks




p.S. wiki pedia does not give accurate info due to it being wrote by morons ty this will be a day that will live in infamy