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=== SWEET MOTHER OF GOD, WE'RE ALL GOING TO DIE, AAAAAAAAAAAAAAAAAAAA!!!!!!!! ===

We are all going to die from this within two weeks.


=== 2009 H1N1 flu outbreak ===
=== 2009 H1N1 flu outbreak ===

Revision as of 18:08, 26 April 2009

Influenza (flu)
H1N1 virus
Types
Vaccines
Treatment
Pandemics
Outbreaks
See also
Pigs can harbor influenza viruses adapted to humans and others that are adapted to birds, allowing the viruses to exchange genes and create a pandemic strain.

Swine influenza virus (referred to as Swine influenza viruses or SIV) refers to influenza cases that are caused by Orthomyxoviruses endemic to pig populations. SIV strains isolated to date have been classified either as Influenzavirus C or one of the various subtypes of the genus Influenzavirus A.[1]

Swine flu infects people every year and is found typically in people who have been in contact with pigs, although there have been cases of person-to-person transmission.[2] Symptoms include fever, disorientation, stiffness of the joints, vomiting, and loss of consciousness ending in death.[3] Swine influenza is known to be caused by influenza A subtypes H1N1,[4] H1N2,[4] H3N1,[5] H3N2,[4] and H2N3.[6]

In swine, three influenza A virus subtypes (H1N1, H3N2, and H1N2) are circulating throughout the world.[citation needed] In the United States, the H1N1 subtype was exclusively prevalent among swine populations before 1998; however, since late August 1998, H3N2 subtypes have been isolated from pigs. Most H3N2 virus isolates are triple reassortants, meaning that it contains genes from human (HA, NA, and PB1), swine (NS, NP, and M), and avian (PB2 and PA) lineages.[citation needed]

H5N1

Avian influenza virus H3N2 is endemic in pigs in China and has been detected in pigs in Vietnam, increasing fears of the emergence of new variant strains.[7] Health experts[who?] say pigs can carry human influenza viruses, which can combine (i.e. exchange homologous genome sub-units by genetic reassortment) with H5N1, passing genes and mutating into a form which can pass easily among humans.[8] H3N2 evolved from H2N2 by antigenic shift.[9] A combination of these two subtypes of the species known as the avian influenza virus in a country like China is a worst case scenario.[10] In August 2004, researchers in China found H5N1 in pigs.[11] Measured resistance to the standard antiviral drugs amantadine and rimantadine in H3N2 in humans has increased to 91% in 2005. [citation needed]

In 2005 it was discovered that H5N1 could be infecting up to half of the pig population in some areas of Indonesia, but without causing symptoms. Chairul Nidom, a virologist at Airlangga University's tropical disease center in Surabaya, East Java, conducted an independent research; he tested the blood of 10 apparently healthy pigs housed near poultry farms in West Java where avian flu had broken out, Nature reported. 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.[12][13]

History

1918 epidemic

Main article: Spanish Flu

In the spring of 1918, bird influenza mutated into a severe human form in just a few months. It was originally thought the strain evolved from a mix of swine flu which humans are more susceptible to and bird flu, with the two strains combining in a pig infected with both strains at the same time. But recovery of the actual 1918 strain from preserved tissue samples revealed it to be a mutated bird flu virus and not a swine flu virus combination.

In the U.S., approximately 675,000 people died.[14] Worldwide, the number of casualties was between 50 and 100 million.[15]

1976 U.S. outbreak

On February 5, 1976, an army recruit at Fort Dix 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 swine flu was the cause of death and that this strain of flu appeared to be closely related to the strain involved in the 1918 flu pandemic. Alarmed public-health officials decided that action must be taken to head off another major pandemic, and they urged President Gerald Ford that every person in the U.S. be vaccinated for the disease. The vaccination program was plagued by delays and public relations problems, but about 24% of the population had been vaccinated by the time the program was canceled.[16]

About 500 cases of Guillain-Barré syndrome, resulting in death from severe pulmonary complications for 25 people, were probably caused by an immunopathological reaction to the vaccine.[16] Other influenza vaccines have not been linked to Guillain-Barré syndrome.[17]

2007 Philippine outbreak

On August 20, 2007 Department of Agriculture officers investigated the outbreak of swine flu in Nueva Ecija and Central Luzon, Philippines. The mortality rate is less than 10% for swine flu, if there are no complications like hog cholera. On July 27, 2007, the Philippine National Meat Inspection Service (NMIS) raised a hog cholera "red alert" warning over Metro Manila and 5 regions of Luzon after the disease spread to backyard pig farms in Bulacan and Pampanga, even if these tested negative for the swine flu virus.[18][19]

SWEET MOTHER OF GOD, WE'RE ALL GOING TO DIE, AAAAAAAAAAAAAAAAAAAA!!!!!!!!

We are all going to die from this within two weeks.

2009 H1N1 flu outbreak

Train commuters in Mexico City wearing surgical masks.
Main article: 2009 H1N1 flu outbreak

In March and April 2009, more than 1,000 cases of swine flu in humans were detected in Mexico, and more than 80 deaths are suspected to have a connection with the virus. As of April 25, 2009 19:30 EDT there are 11 laboratory confirmed cases in the southwestern United States and in Kansas,[20] and several suspected cases in the New York City metropolitan area. Following a series of reports of isolated cases of swine flu,[21][22] the first announcement of the outbreak in Mexico was documented on April 23, 2009. Some of the cases have been confirmed by the World Health Organization to be due to a new genetic strain of H1N1.[23][24] The new strain has been confirmed in 16 of the deaths and 44 others are being tested as of April 24, 2009.[25] The Mexican fatalities are said to be mainly young adults, a hallmark of pandemic flu.[26]

At 8 p.m. on Sunday, April 26, the New Zealand Minister of Health confirmed that 22 students returning from a school trip from Mexico had flu like symptoms (most likely swine flu). 13 of the students with flu like symptoms were tested and 10 tested positive for Influenza A, their cases strongly suspected to be the swine flu strain. However there is a possibility that the infected are not infected with the swine flu but other forms of the flu. The government has suggested that citizens of New Zealand with flu-like symptoms should see their G.P. immediately.

There have been five cases of possible swine flu in Canada, according to the Canadian Press. Two in British Columbia, and three in Nova Scotia. According to the Government of Nova Scotia, four students in Windsor, Nova Scotia have confirmed cases of swine flu.[27]

The new strain appears to be a recombinant between two older strains. Preliminary genetic characterization found that the hemagglutinin (HA) gene was similar to that of swine flu viruses present in U.S. pigs since 1999, but the neuraminidase (NA) and matrix protein (M) genes resembled versions present in European swine flu isolates. Viruses with this genetic makeup had not previously been found to be circulating in humans or pigs, but there is no formal national surveillance system to determine what viruses are circulating in pigs in the U.S.[28]

According to University of Virginia virologist Frederick Hayden, the most recent flu season was dominated by H1N1 viruses, and people who had received flu shots in the U.S. may have some protection against swine flu.[29]

Veterinary swine flu vaccine

Swine influenza has become a greater problem in recent decades as the evolution of the virus 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.[30][31]

Present vaccination 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.[32][33]

The current vaccine against the seasonal influenza strain H1N1 is thought unlikely to provide protection.[34] The director of CDC's National Center for Immunization and Respiratory Diseases said that the United States' cases were found to be made up of genetic elements from four different flu viruses—North American swine influenza, North American avian influenza, human influenza A virus subtype H1N1, and swine influenza virus typically found in Asia and Europe. On two cases, a complete genome sequence had been obtained. She said that the virus is resistant to amantadine and rimantadine, but susceptible to oseltamivir (Tamiflu) and zanamivir (Relenza).[35][36][37]

See also

Further reading

References

  1. ^ Heinen P. (15 September 2003). "Swine influenza: a zoonosis". Veterinary Sciences Tomorrow. 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.
  2. ^ Cuevas Mayra, Curley Ann, Hellerman Caleb, Quijano Elaine, Candiotti Susan (25 April 2009). "More cases of swine flu reported; WHO warns of health emergency".{{cite news}}: CS1 maint: multiple names: authors list (link)
  3. ^ "World Health Organization: Swine flu could spread globally". CNN.com. Retrieved 2009-04-25.
  4. ^ a b c "Swine Influenza". Swine Diseases (Chest). Iowa State University College of Veterinary Medicine.
  5. ^ eurekalert Tips from the Journals of the American Society for Microbiology - Novel H3N1 Swine Influenza Virus Identified in Pigs in Korea
  6. ^ PNAS Published online before print December 18, 2007, doi: 10.1073/pnas.0710286104 PNAS December 26, 2007 vol. 104 no. 52 20949-20954
  7. ^ Yu, H. (2008). "Genetic evolution of swine influenza A (H3N2) viruses in China from 1970 to 2006". Journal of Clinical Microbiology. 46 (3): 1067. doi:10.1128/JCM.01257-07. PMID 18199784. {{cite journal}}: Unknown parameter |month= ignored (help)
  8. ^ "Bird flu and pandemic influenza: what are the risks?". UK Department of Health.
  9. ^ "Genetic analysis of human H2N2 and early H3N2 influenza viruses, 1957–1972: evidence for genetic divergence and multiple reassortment events". ScienceDirect.
  10. ^ "Economic impact of avian flu". The World Bank.
  11. ^ WHO (October 28, 2005). "H5N1 avian influenza: timeline" (PDF).
  12. ^ "Indonesian pigs have avian flu virus; bird cases double in China". CIDRAP. 27 May 2005.
  13. ^ . 31 March 2009 http://www.cidrap.umn.edu/cidrap/content/influenza/avianflu/news/mar3109swine-jw.html. {{cite news}}: Missing or empty |title= (help) report on Pigs as carriers
  14. ^ Pandemics and Pandemic Threats since 1900. U.S. Department of Health & Human Services
  15. ^ Taubenberger JK, Morens DM (2006). "1918 Influenza: the mother of all pandemics". Emerg Infect Dis. 12 (1). Centers for Disease Control and Prevention (CDC). {{cite journal}}: Unknown parameter |month= ignored (help)
  16. ^ a b "The sky is falling: an analysis of the swine flu affair of 1976". Haverford.edu. Retrieved 2009-04-25. [dubious – discuss]
  17. ^ "Influenza / Flu Vaccine". University of Illinois at Springfield. Retrieved 26 April 2009.
  18. ^ "DA probes reported swine flu 'outbreak' in N. Ecija". Gmanews.tv. Retrieved 2009-04-25.
  19. ^ "Gov't declares hog cholera alert in Luzon". Gmanews.tv. Retrieved 2009-04-25.
  20. ^ "Human swine influenza investigation". Center for Disease Control and Prevention. 24 April 2009. Retrieved 2009-04-25.
  21. ^ Stobbe Mike (April 21, 2009). "Officials alert doctors after 2 California children infected with unusual swine flu". Associated Press. Retrieved April 24, 2009.
  22. ^ Brown David (22 April 2009). "New Strain of Swine Flu Investigated: Two Children in San Diego Area Had No Contact With Pigs". Washington Post. Retrieved April 24, 2009.
  23. ^ "Q&A: Swine flu". BBC News.
  24. ^ "Influenza-like illness in the United States and Mexico". World Health Organization. 24 April 2009.
  25. ^ "Experts probe deadly Mexico flu". 24 April 2009.
  26. ^ "Deadly new flu virus in US and Mexico may go pandemic". New Scientist. 24 April 2009.
  27. ^ "Swine Influenza Live Webcast". Government of Nova Scotia. 2009-04-26.
  28. ^ "Swine Influenza A (H1N1) Infection in Two Children --- Southern California, March--April 2009". MMWR. Centers for Disease Control. 22 April 2009.
  29. ^ "Swine flu emergency caused by new variant of old bug". Bloomberg. 2009-04-26.
  30. ^ "Swine flu virus turns endemic". National Hog Farmer. 15 September 2007.
  31. ^ "Swine". Custom Vaccines. Novartis.
  32. ^ Gramer Marie René, Lee Jee Hoon, Choi Young Ki, Goyal Sagar M, Joo Han Soo (July 2007). "Serologic and genetic characterization of North American H3N2 swine influenza A viruses". Canadian Journal of Veterinary Research. 71 (3): 201–206. PMID 1899866.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  33. ^ Myers KP, Olsen CW, Gray GC (2007). "Cases of swine influenza in humans: a review of the literature". Clin Infect Dis. 44 (8): 1084–8. doi:10.1086/512813. PMC 1973337. PMID 17366454. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  34. ^ "Update: Swine Influenza A (H1N1) Infections --- California and Texas, April 2009". MMWR. Centrers for Disease Control. 24 April 2009.
  35. ^ Steven Reinberg (24 April 2009). "Swine Flu Cases Now Total 7: CDC". ABC News.
  36. ^ Rob Stein (23 April 2009). "In California and Texas, 5 New Swine Flu Cases". Washington Post.
  37. ^ "CDC Briefing on Public Health Investigation of Human Cases of Swine Influenza". CDC online newsroom. 23 April 2009.
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