Changes

==Mechanism==

==Mechanism==

If the body produces an antibody against a particular disease or toxin it can identify the infection early on and the [[immune system]] can destroy it. Vaccines work by exposing the body to a form of the disease in such a way that it is much less likely cause illness but still allows antibodies to develop. This confers a level of immunity to the person or animal vaccinated.<ref>http://www.howstuffworks.com/immune-system7.htm How stuff works: Antibodies</ref>

If the body produces an antibody against a particular disease or toxin it can identify the infection early on and the [[immune system]] can destroy it. Vaccines work by exposing the body to a form of the disease in such a way that it is much less likely to cause illness but still allows antibodies to develop. This confers a level of immunity to the person or animal vaccinated.<ref>http://www.howstuffworks.com/immune-system7.htm How stuff works: Antibodies</ref>

Since the adoption of mass vaccination programs, many diseases have been curbed. [[Smallpox]], a contagious disease that killed 30 percent of those it infected, has been entirely eliminated through vaccination, excepting some strains maintained in labs for research purposes. Vaccination programs of the 19th and 20th century were effective at curbing the disease, and in 1979 the World Health Organization declared smallpox to be eradicated.<ref>https://www.cdc.gov/smallpox/history/history.html</ref>

Since the adoption of mass vaccination programs, many diseases have been curbed. [[Smallpox]], a contagious disease that killed 30 percent of those it infected, has been entirely eliminated through vaccination, excepting some strains maintained in labs for research purposes. Vaccination programs of the 19th and 20th century were effective at curbing the disease, and in 1979 the World Health Organization declared smallpox to be eradicated.<ref>https://www.cdc.gov/smallpox/history/history.html</ref>

While vaccines have been successful at preventing infectious disease, they have also resulted in controversy regarding their safety and effectiveness, legal and ethical issues surrounding mandatory vaccination, and whether children should be vaccinated against STDs<ref>https://www.historyofvaccines.org/content/articles/ethical-issues-and-vaccines</ref><ref>https://www.nvic.org/NVIC-Vaccine-News/January-2018/are-vaccine-ingredients-safe.aspx</ref>

While vaccines have been successful at preventing infectious disease, they have also resulted in controversy regarding their safety and effectiveness, legal and ethical issues surrounding mandatory vaccination, and whether children should be vaccinated against STDs<ref>https://www.historyofvaccines.org/content/articles/ethical-issues-and-vaccines</ref><ref>https://www.nvic.org/NVIC-Vaccine-News/January-2018/are-vaccine-ingredients-safe.aspx</ref>

There are five major types of vaccines and they are differentiated by what type of antigen is used. Live attenuated vaccines are created from the actual disease in question, however before injection the [[pathogen]] is [[attenuated]] (weakened) by growing successive generations of the pathogen in poor nutrient conditions. Because they contain live pathogens, it is still possible for these vaccines to cause infection, particularly in imunnocompromised individuals. Inactivated vaccines are created from pathogens that have been killed, usually with [[formaldehyde]]. Toxoid vaccines are created by using toxins produced by the pathogen, these toxins are exposed to heat and/or chemicals such as formaldehyde to inactivate the toxins, but [[antibodies]] that are produced to these deactivated toxins will also protect against the real toxin. Subunit vaccines use pieces of the pathogen in the vaccine. These pieces often consist of unique protein segments that stimulate the production of antibodies. Finally, conjugate vaccines protect against bacteria that are encapsulated in polysaccharides (complex sugars), which disguise the bacteria, making it hard for the immune system to recognize them. Conjugate vaccines overcome this by attaching the sugar to a protein the does stimulate the immune system, thus triggering the immune system to react to the sugar in the future even if it is not accompanied by the protein.<ref>https://www.cdc.gov/vaccines/hcp/conversations/downloads/vacsafe-understand-color-office.pdf</ref>

There are five major types of vaccines and they are differentiated by what type of antigen is used. Live attenuated vaccines are created from the actual disease in question, however before injection the [[pathogen]] is [[attenuated]] (weakened) by growing successive generations of the pathogen in poor nutrient conditions. Because they contain live pathogens, it is still possible for these vaccines to cause infection, particularly in immunocompromised individuals. Inactivated vaccines are created from pathogens that have been killed, usually with [[formaldehyde]]. Toxoid vaccines are created by using toxins produced by the pathogen, these toxins are exposed to heat and/or chemicals such as formaldehyde to inactivate the toxins, but [[antibodies]] that are produced to these deactivated toxins will also protect against the real toxin. Subunit vaccines use pieces of the pathogen in the vaccine. These pieces often consist of unique protein segments that stimulate the production of antibodies. Finally, conjugate vaccines protect against bacteria that are encapsulated in polysaccharides (complex sugars), which disguise the bacteria, making it hard for the immune system to recognize them. Conjugate vaccines overcome this by attaching the sugar to a protein the does stimulate the immune system, thus triggering the immune system to react to the sugar in the future even if it is not accompanied by the protein.<ref>https://www.cdc.gov/vaccines/hcp/conversations/downloads/vacsafe-understand-color-office.pdf</ref>

==Influenza Vaccine==

==Influenza Vaccine==

The flu vaccine is an example of modern vaccination. Due to the change in [[allele]] frequency over time in the population of the influenza virus, new influenza vaccines are created each year.  In some years the vaccines are less effective than in other years. According to the [https://www.cdc.gov/ CDC],<ref>"Inactivated Influenza Vaccine, What you need to know," a publication of the Center for Disease Control, 2006. Available online at: https://www.cdc.gov/nip/publications/VIS/vis-flu.pdf</ref>  

The flu vaccine is an example of modern vaccination. Due to the change in [[allele]] frequency over time in the population of the influenza virus, new influenza vaccines are created each year.  In some years the vaccines are less effective than in other years. According to the [https://www.cdc.gov/ CDC],<ref>"Inactivated Influenza Vaccine, What you need to know," a publication of the Center for Disease Control, 2006. Available online at: https://www.cdc.gov/nip/publications/VIS/vis-flu.pdf</ref>  

<blockquote>

<blockquote>

Influenza viruses are always changing. Therefore, influenza vaccines are updated every year, and an annual vaccination is recommended.

Influenza viruses are always changing. Therefore, influenza vaccines are updated every year, and annual vaccination is recommended.

</blockquote>

</blockquote>

Since production of the vaccine must begin many months before the influenza season starts models of the population genetics of the virus must be produced.<ref>http://www.nature.com/nrd/journal/v5/n3/full/nrd1988.html Influenza vaccines</ref> The success of vaccinations programs is dependent on the accuracy of these predictions.<ref>http://www.nature.com/news/2003/030324/full/030324-5.html Flu changes modeled</ref> The National Institute of Health recently assigned $26 million to establish a research center to better develop molecular models of influenza.<ref>http://www.spiritindia.com/health-care-news-articles-8024.html $26 million NIH contract to establish new flu/bird flu Center of Excellence</ref>

Since the production of the vaccine must begin many months before the influenza season starts models of the population genetics of the virus must be produced.<ref>http://www.nature.com/nrd/journal/v5/n3/full/nrd1988.html Influenza vaccines</ref> The success of vaccinations programs is dependent on the accuracy of these predictions.<ref>http://www.nature.com/news/2003/030324/full/030324-5.html Flu changes modeled</ref> The National Institute of Health recently assigned $26 million to establish a research center to better develop molecular models of influenza.<ref>http://www.spiritindia.com/health-care-news-articles-8024.html $26 million NIH contract to establish new flu/bird flu Center of Excellence</ref>

==Herd immunity and mandatory vaccination==

==Herd immunity and mandatory vaccination==

When a certain percentage of a population is vaccinated, those within the population who are not vaccinated are protected from the disease, this is called [[herd immunity]]. If 90 percent of a population is immune, then the chances that a carrier of the disease will come into contact with a non-immune member of the population (or "herd") is low.<ref>http://www.mathepi.com/maindir/herd.html The mathematics of herd immunity</ref> Herd immunity is the goal of most vaccination programs as it is the point where a disease can start to be eliminated from a population altogether.   

When a certain percentage of a population is vaccinated, those within the population who are not vaccinated are protected from the disease, this is called [[herd immunity]]. If 90 percent of a population is immune, then the chances that a carrier of the disease will come into contact with a non-immune member of the population (or "herd") is low.<ref>http://www.mathepi.com/maindir/herd.html The mathematics of herd immunity</ref> Herd immunity is the goal of most vaccination programs as it is the point where disease can start to be eliminated from a population altogether.   

For example, in 1962 Japan instituted mandatory vaccination against influenza in school children. This continued until 1987 when the program was changed to optional; it was abandoned in 1994. Approximately 85 percent of children were estimated to have been vaccinated.<ref>{{hnb|Glezen|2004}}</ref> Several studies examined the mortality rates due to influenza during this period of time and revealed that the death rates due to influenza in all population groups was drastically decreased, including older adult populations. Since there was no increased rate of vaccination in these populations, the decreased mortality was caused by herd immunity effects of vaccinating so many children.<ref>http://www.newsrx.com/newsletters/Vaccine-Weekly/2001-04-11/200104113335VW.html Mandatory Vaccination of Japanese Schoolchildren Demonstrates "Herd Immunity"</ref> Many researchers have written that this and other evidence argues strongly for mandatory vaccination programs worldwide as a means of controlling many diseases and preventing a [[pandemic]].<ref>http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1360502 Herd Immunity</ref>

For example, in 1962 Japan instituted mandatory vaccination against influenza in school children. This continued until 1987 when the program was changed to optional; it was abandoned in 1994. Approximately 85 percent of children were estimated to have been vaccinated.<ref>{{hnb|Glezen|2004}}</ref> Several studies examined the mortality rates due to influenza during this period of time and revealed that the death rates due to influenza in all population groups were drastically decreased, including older adult populations. Since there was no increased rate of vaccination in these populations, the decreased mortality was caused by herd immunity effects of vaccinating so many children.<ref>http://www.newsrx.com/newsletters/Vaccine-Weekly/2001-04-11/200104113335VW.html Mandatory Vaccination of Japanese Schoolchildren Demonstrates "Herd Immunity"</ref> Many researchers have written that this and other evidence argues strongly for mandatory vaccination programs worldwide as a means of controlling many diseases and preventing a [[pandemic]].<ref>http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1360502 Herd Immunity</ref>

The USA has federal vaccination recommendations according to an official CDC schedule. Requirements are up to the states. Most states have medical and religious exemptions. Some states make it very easy to opt out of vaccines, while other states strictly enforce compliance for school attendance. The difference in vaccination rates between these states is actually very slight, and usually not nearly enough to affect herd immunity.{{cn}}

The USA has federal vaccination recommendations according to an official CDC schedule. Requirements are up to the states. Most states have medical and religious exemptions. Some states make it very easy to opt-out of vaccines, while other states strictly enforce compliance for school attendance. The difference in vaccination rates between these states is actually very slight, and usually not nearly enough to affect herd immunity.{{cn}}

As of February 2008, the CDC noted that "fewer than 100 measles cases are now reported annually in the United States and virtually all of those are linked to imported cases" in which someone is infected during overseas travel. The USA maintains herd immunity for measles, even in states where it is easy to opt out of vaccination requirements.<ref>[https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5708a3.htm]</ref> Measles can be serious; according to an article in The Times, "About one in every 15 children has complications that can include [[meningitis]], [[pneumonia]], [[fits]], [[encephalitis]] (swelling of the brain), [[blindness]] and [[brain damage]]."<ref>The Sunday Times, ''How the MMR scare led to the return of measles'', February 8, 2009 [http://www.timesonline.co.uk/tol/life_and_style/health/article5683687.ece]</ref> In the England and Wales, there were 1,348 cases of measles in 2008; two children died of the disease.<ref>The Sunday Times, ''MMR doctor Andrew Wakefield fixed data on autism'', by Brian Deer, February 8, 2009 [http://www.timesonline.co.uk/tol/life_and_style/health/article5683671.ece]</ref>

As of February 2008, the CDC noted that "fewer than 100 measles cases are now reported annually in the United States and virtually all of those are linked to imported cases" in which someone is infected during overseas travel. The USA maintains herd immunity for measles, even in states where it is easy to opt-out of vaccination requirements.<ref>[https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5708a3.htm]</ref> Measles can be serious; according to an article in The Times, "About one in every 15 children has complications that can include [[meningitis]], [[pneumonia]], [[fits]], [[encephalitis]] (swelling of the brain), [[blindness]] and [[brain damage]]."<ref>The Sunday Times, ''How the MMR scare led to the return of measles'', February 8, 2009 [http://www.timesonline.co.uk/tol/life_and_style/health/article5683687.ece]</ref> In the England and Wales, there were 1,348 cases of measles in 2008; two children died of the disease.<ref>The Sunday Times, ''MMR doctor Andrew Wakefield fixed data on autism'', by Brian Deer, February 8, 2009 [http://www.timesonline.co.uk/tol/life_and_style/health/article5683671.ece]</ref>

The CDC notes that when a measles outbreak occurs, the cost to taxpayers can be substantial. Public health responsibilities include "identification of cases, isolation of patients and vaccination, administration of [[immune globulin]], and voluntary quarantine of contacts who have no evidence of measles immunity...In Iowa, the public health response to one imported measles case cost approximately $150,000."<ref>Centers for Disease Control and Prevention, Morbidity and Mortality Weekly Report, ''Outbreak of Measles --- San Diego, California, January--February 2008'', February 29, 2008 [https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5708a3.htm]</ref>

The CDC notes that when a measles outbreak occurs, the cost to taxpayers can be substantial. Public health responsibilities include "identification of cases, isolation of patients and vaccination, administration of [[immune globulin]], and voluntary quarantine of contacts who have no evidence of measles immunity...In Iowa, the public health response to one imported measles case cost approximately $150,000."<ref>Centers for Disease Control and Prevention, Morbidity and Mortality Weekly Report, ''Outbreak of Measles --- San Diego, California, January--February 2008'', February 29, 2008 [https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5708a3.htm]</ref>

===Herd Immunity in Britain===

===Herd Immunity in Britain===

Due to a decrease in vaccination, measles has become endemic in Britain. This means that measles does not need to be brought in by travelers, but instead has a large enough base of non-immune individuals for it to continuously spread inside the country. In London, only 71 percent of children receive the first dose of the vaccine and only 51 percent receive the second dose. Due to this decline, there were 461 measles cases in Britain in the first half of 2008. These cases have had tragic consequences, with the death of a 17 year old reported in 2008.<ref>[http://www.healthdirect.co.uk/2008/07/measles-endemic-in-britain-official.html Health Direct NHS watch blog]</ref> This immunization failure is due to parents opting out of the MMR vaccine program in the wake of the false claims that the MMR vaccine causes autism.<ref>http://www.timesonline.co.uk/tol/news/world/us_and_americas/article4100287.ece</ref>{{dead link}}

Due to a decrease in vaccination, measles has become endemic in Britain. This means that measles does not need to be brought in by travelers, but instead has a large enough base of non-immune individuals for it to continuously spread inside the country. In London, only 71 percent of children receive the first dose of the vaccine and only 51 percent receive the second dose. Due to this decline, there were 461 measles cases in Britain in the first half of 2008. These cases have had tragic consequences, with the death of a 17-year-old reported in 2008.<ref>[http://www.healthdirect.co.uk/2008/07/measles-endemic-in-britain-official.html Health Direct NHS watch blog]</ref> This immunization failure is due to parents opting out of the MMR vaccine program in the wake of the false claims that the MMR vaccine causes autism.<ref>https://www.thetimes.co.uk/article/no-doubt-the-mmr-vaccine-does-not-cause-autism-zpxk37ntzmh</ref>

== Adverse Reactions ==

== Adverse Reactions ==

{{See also|Vaccine Injury Compensation Program|Vaccine Adverse Event Reporting System}}

{{See also|Vaccine Injury Compensation Program|Vaccine Adverse Event Reporting System}}

Vaccines have substantial side effects, and many vaccines have a significant morbidity and mortality associated with them. In fiscal year 2017 alone, it is estimated that $220 million will be paid to victims of vaccines, and underpayments or improper denials of payment are common.<ref>http://www.wakingtimes.com/2017/05/09/whopping-vaccine-injury-payouts-us-fiscal-year-2017-released/</ref> More than Postvaccinial encephalitis is a known hazard of [[smallpox]] vaccine, for example. A recently introduced vaccine against human papilloma virus, the causative agent of cancer of the [[uterus|uterine]] cervix, has now been linked to a number of sudden deaths reported within days of its administration.<ref name=GardasilMM>Cockcroft, Lucy, "[https://www.telegraph.co.uk/news/main.jhtml?xml=/news/2007/10/29/njab129.xml Cervical cancer drug Gardasil linked to deaths]," ''[[London]] Daily Telegraph'', October 29, 2007. Retrieved November 10, 2007.</ref>

Vaccines have substantial side effects, and many vaccines have significant morbidity and mortality associated with them. In the fiscal year 2017 alone, it is estimated that $220 million will be paid to victims of vaccines, and underpayments or improper denials of payment are common.<ref>http://www.wakingtimes.com/2017/05/09/whopping-vaccine-injury-payouts-us-fiscal-year-2017-released/</ref> More than Postvaccinial encephalitis is a known hazard of [[smallpox]] vaccine, for example. A recently introduced vaccine against human papilloma virus, the causative agent of cancer of the [[uterus|uterine]] cervix, has now been linked to a number of sudden deaths reported within days of its administration.<ref name=GardasilMM>Cockcroft, Lucy, "[https://www.telegraph.co.uk/news/main.jhtml?xml=/news/2007/10/29/njab129.xml Cervical cancer drug Gardasil linked to deaths]," ''[[London]] Daily Telegraph'', October 29, 2007. Retrieved November 10, 2007.</ref>

Bulging or swollen [[fontanelle]]s have been linked with many vaccines commonly given to infants, such as the diphtheria-[[tetanus]] (DPT) vaccine. Many families, out of concern for their child's health, have sought legal justice for the potential health damage.<ref>http://legaljustice4john.com/fontanellebulging.htm</ref>

Bulging or swollen [[fontanelle]]s have been linked with many vaccines commonly given to infants, such as the diphtheria-[[tetanus]] (DPT) vaccine. Many families, out of concern for their child's health, have sought legal justice for the potential health damage.<ref>http://legaljustice4john.com/fontanellebulging.htm</ref>

===Published Adverse Reaction Rates===

===Published Adverse Reaction Rates===

Most medical journals and the CDC are heavily influenced by vaccine manufacturers, and hence their published information about side effects are one-sided.  The packaging labels on vaccines are more candid.

Most medical journals and the CDC are heavily influenced by vaccine manufacturers, and hence their published information about side effects is one-sided.  The packaging labels on vaccines are more candid.

This is what the CDC and medical journals claim:

This is what the CDC and medical journals claim:

*The Hepatitis B Vaccine (HBV) has a .000167% chance of causing [[anaphylaxis]] upon vaccination.<ref>[https://www.cdc.gov/mmwr/preview/mmwrhtml/00046738.htm]</ref>  

*The Hepatitis B Vaccine (HBV) has a .000167% chance of causing [[anaphylaxis]] upon vaccination.<ref>[https://www.cdc.gov/mmwr/preview/mmwrhtml/00046738.htm]</ref>  

*There is no correlation between the HBV and multiple sclerosis.<ref>[http://www.medsafe.govt.nz/Profs/PUarticles/vaccinenews.htm]</ref>

*There is no correlation between the HBV and multiple sclerosis.<ref>[http://www.medsafe.govt.nz/Profs/PUarticles/vaccinenews.htm]</ref>

*The Measles, Mumps, Rubbela (MMR) vaccine has a 25% chance of causing [[arthralgia]] (joint pain) and 10% chance of causing [[arthritis]]-like symptoms in women who are past puberty. This pain and stiffness begins 1–3 weeks after vaccination, persisting for 1 day to 3 weeks.<ref>[https://www.cdc.gov/vaccines/vpd-vac/combo-vaccines/mmr/faqs-mmr-hcp.htm]</ref>

*The Measles, Mumps, Rubella (MMR) vaccine has a 25% chance of causing [[arthralgia]] (joint pain) and a 10% chance of causing [[arthritis]]-like symptoms in women who are past puberty. This pain and stiffness begin 1–3 weeks after vaccination, persisting for 1 day to 3 weeks.<ref>[https://www.cdc.gov/vaccines/vpd-vac/combo-vaccines/mmr/faqs-mmr-hcp.htm]</ref>

*The MMR vaccine has a .00484% chance of causing [[thrombocytopenia]]. However, the measles and rubella both have much higher chances of causing thrombocytopenia.<ref>[http://adc.bmj.com/cgi/content/full/84/3/227 E Miller et al., Idiopathic thrombocytopenic purpura and MMR vaccine in ''Archives of Disease In Childhood'', 84:227-229]</ref>

*The MMR vaccine has a .00484% chance of causing [[thrombocytopenia]]. However, the measles and rubella both have much higher chances of causing thrombocytopenia.<ref>[http://adc.bmj.com/cgi/content/full/84/3/227 E Miller et al., Idiopathic thrombocytopenic purpura and MMR vaccine in ''Archives of Disease In Childhood'', 84:227-229]</ref>

*[http://www.909shot.com/ National Vaccine Information Center (NVIC)], a non-profit anti-vaccination organization

*[http://www.909shot.com/ National Vaccine Information Center (NVIC)], a non-profit anti-vaccination organization

*[http://www.site.stopjenny.com/uploads/Compare_Risks.pdf Compare the Risks], A PDF detailing the risks between vaccination and non-vaccination

*[http://www.site.stopjenny.com/uploads/Compare_Risks.pdf Compare the Risks], A PDF detailing the risks between vaccination and non-vaccination

*[http://www.site.stopjenny.com/Home.html Stop Jenny McCarthy], A site devoted to fighting vaccine misinformation, contains many vaccine related resources.

*[http://www.site.stopjenny.com/Home.html Stop Jenny McCarthy], A site devoted to fighting vaccine misinformation, contains many vaccine-related resources.

[[Category:Biology]]

[[Category:Biology]]

[[Category:Medicine]]

[[Category:Medicine]]