VaccinesAvaccineis a biological preparation that provides active acquired immunity to a particulardisease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins. The agent stimulates the body'simmune systemto recognize the agent as a threat, destroy it, and keep a record of it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters. Examples: Measles, mumps, rubella (MMR combined vaccine) Varicella (chickenpox), Influenza (nasal spray) and Rotavirus.

BENEFITS

Infections caused byHaemophilus influenzae, a major cause ofbacterial meningitisand other serious diseases in children, have decreased by over 99% in the US since the introduction of a vaccine in 1988.Full vaccination, from birth to adolescence, of all US children born in a given year saves an estimated 33,000 lives and prevents an estimated 14 million infections.

Population healthIncomplete vaccine coverage increases the risk of disease for the entire population, including those who have been vaccinated, because it reducesherd immunity. Herd immunityis a form ofimmunitythat occurs when the vaccination of a significant portion of a population (orherd) provides a measure of protection for individuals who have not developedimmunity. Increasing herd immunity during an outbreak or threatened outbreak is perhaps the most widely accepted justification for mass vaccination. Mass vaccination also helps to increase coverage rapidly, thus obtaining herd immunity, when a new vaccine is introduced.

Cost-effectivenessCommonly used vaccines are a cost-effective and preventive way of promoting health, compared to the treatment of acute or chronic disease. In the US during the year 2001, routinechildhood immunizationsagainst seven diseases were estimated to save over $40 billion per birth-year cohort in overall social costs, including $10 billion in directhealth costs, and the societal benefit-cost ratio for these vaccinations was estimated to be 16.5.

Eradication of diseaseWith some vaccines, a goal of vaccination policies is to eradicate the disease - make it disappear from Earth altogether. The World Health Organizationcoordinated the global effort to eradicatesmallpoxglobally. Victory is also claimed for getting rid of endemicmeasles,mumpsandrubellain Finland. The last naturally occurring case of smallpox occurred in Somalia in 1977. In 1988, the governing body of WHO targetedpolio for eradicationby the year 2000, but didn't succeed. The next eradication target would most likely be measles, which has declined since the introduction of measles vaccination in 1963.

Individual versus group goalsRational individualswill attempt to minimize the risk of illness, and will seek vaccination for themselves or their children if they perceive a high threat of disease and a low risk to vaccination. However, if a vaccination program successfully reduces the disease threat, it may reduce the perceived risk of disease enough so that an individual's optimal strategy is to encourage everyone but their family to be vaccinated, or (more generally) to refuse vaccination at coverage levels below those optimal for the community.For example, a 2003 study found that abioterroristattack usingsmallpoxwould result in conditions where voluntary vaccination would be unlikely to reach the optimum level for the U.S. as a whole,and a 2007 study found that severeinfluenza epidemicscannot be prevented by voluntary vaccination without offering certain incentives.Governments often allow exemptions to mandatory vaccination for religious or philosophical reasons, but decreased rates of vaccination may cause loss ofherd immunity, substantially increasing risks even to vaccinated individuals.

Events following reductions in vaccinationUK, pertussis (1970s80s)In a 1974 report ascribing 36 reactions towhooping cough(pertussis) vaccine, a prominent public-health academic claimed that the vaccine was only marginally effective and questioned whether its benefits outweigh its risks, and extended television and press coverage caused a scare. Vaccine uptake in the UK decreased from 81% to 31%, and pertussis epidemics followed, leading to the deaths of some children. Mainstream medical opinion continued to support the effectiveness and safety of the vaccine; public confidence was restored after the publication of a national reassessment of vaccine efficacy. Vaccine uptake then increased to levels above 90%, and disease incidence declined dramatically

Nigeria, polio, measles, diphtheria (2001)In the early first decade of the 21st century, conservative religious leaders in northernNigeria, suspicious ofWestern medicine, advised their followers not to have their children vaccinated with oral polio vaccine. The boycott was endorsed by the governor ofKano State, and immunization was suspended for several months. Subsequently, polio reappeared in a dozen formerly polio-free neighbors of Nigeria, and genetic tests showed the virus was the same one that originated in northern Nigeria. Nigeria had become a net exporter of the polio virus to its African neighbors. People in the northern states were also reported to be wary of other vaccinations, and Nigeria reported over 20,000 measles cases and nearly 600 deaths from measles from January through March 2005.[54]In 2006, Nigeria accounted for over half of all new polio cases worldwide.[55]Outbreaks continued thereafter; for example, at least 200 children died in a late-2007 measles outbreak inBorno State.[56]Multiple states, United States, measles (2013)In 2000, measles was declared eliminated from the United States because internal transmission had been interrupted for one year; remaining reported cases were due to importationCenters for Disease Control and Prevention(CDC) reported that the three biggest outbreaks of measles in 2013 were attributed to clusters of people who were unvaccinated due to their philosophical or religious beliefs. As of August 2013, three pockets of outbreakNew York City, North Carolina, and Texascontributed to 64% of the 159 cases of measles reported in 16 statesThe number of cases in 2014 quadrupled to 644 including transmission by unvaccinated visitors to Disneyland in California.[63]Some 97% of cases in the first half of the year were confirmed to be due directly or indirectly to importation (the remainder were unknown), and 49% from the Phillippines. 165 of the 288 victims (57%) during that time were confirmed to be unvaccinated by choice; 30 (10%) were confirmed to have been vaccinated. OPPOSTION TO VACCINESAutism controversies2011 journal article described the vaccine-autism connection as "the most damaging medical hoax of the last 100 years". 2013 Journal of Pediatrics, USA states that autism is not linked to vaccines.

Governments Should Not Infringe On an Individual's Freedom to Choose Medications, Even If That Choice Increases the Risk of Disease to Themselves and Others If a vaccination program successfully reduces the disease threat, it may reduce the perceived risk of disease enough that an individual's optimal strategy is to refuse vaccination at coverage levels below those optimal for the community. Exempting some people from mandatory vaccination results in afree-rider problem, in which a few individuals gain the advantage ofherd immunity without paying the cost; decreased rates of vaccinations such as through exemptions may cause loss of herd immunity,substantially increasing risks even to certain vaccinated individuals.

Religion1. Some Christian opponents argued, when vaccination was first becoming widespread, that if God had decreed that someone should die of smallpox, it would be a sin to thwart God's will via vaccination.Many governments allow parents to opt out of their children's otherwise mandatory vaccinations for religious reasons; some parents falsely claim religious beliefs to get vaccination exemptions. 2. TheHaredi burqa sectin Israel took a moral stand against vaccinations or medical treatments, which led to the death of at least one baby from untreated influenza. 3. The cell culture media of some viral vaccines, and the virus of therubellavaccine, are derived from tissues taken from therapeutic abortions performed in the 1960s, leading to moral questions. For example, theprinciple of double effect, originated byThomas Aquinas, holds that actions with both good and bad consequences are morally acceptable in specific circumstances, and the question is how this principle applies to vaccination4. The Vatican Curia has expressed concern about the rubella vaccine's embryonic cell origin, saying that Catholics have "a grave responsibility to use alternative vaccines and to make a conscientious objection with regard to those which have moral problems." The Vatican concluded that until an alternative becomes available, it is acceptable forCatholicsto use the existing vaccine, writing, "This is an unjust alternative choice, which must be eliminated as soon as possible."

ChiropracticIts belief that all diseases were traceable to causes in the spine and therefore could not be affected by vaccines;Daniel D. Palmer, the founder of chiropractic, wrote, "It is the very height of absurdity to strive to 'protect' any person from smallpox or any other malady by inoculating them with a filthy animal.TheAmerican Chiropractic Associationand the International Chiropractic Association support individual exemptions to compulsory vaccination laws; a 1995 survey of US chiropractors found that about one third believed there was no scientific proof that immunization prevents diseaseSome chiropractic groups still oppose attempts to limit or eliminate nonmedical exemptions to vaccination. In March 2015, the Oregon Chiropractic Association invitedAndrew Wakefield, chief author of afraudulent research paper, to testify against Senate Bill 442,[126]"a bill that would eliminate nonmedical exemptions from Oregon's school immunization law."[127]The California Chiropractic Association lobbied against a 2015 bill ending belief exemptions for vaccines. They had also opposed a 2012 bill related to vaccination exemptions.

HomeopathySeveral surveys have shown that some practitioners ofhomeopathy, particularly homeopaths without any medical training, advise patients against vaccination.[129]For example, a survey of registered homeopaths in Austria found that only 28% considered immunization an important preventive measure, and 83% of homeopaths surveyed inSydney, Australia, did not recommend vaccination. Financial motives (conspiracy theory)Critics have accused the vaccine industry of misrepresenting the safety and effectiveness of vaccines, covering up and suppressing information, and influencing health policy decisions for financial gain.[2]Conversely, many groups profit by promoting the controversiality of vaccines, such as lawyers who receive fees often totalling millions of dollars, expert witnesses paid to provide testimony and to speak at conferences, and practitioners of alternative medicine offering ineffective and expensive medications, supplements, and procedures such aschelation therapyandhyperbaric oxygen therapy.[131]In the late 20th century, vaccines were a product with lowprofit margins,[132]and the number of companies involved in vaccine manufacture declined. In addition to low profits and liability risks, manufacturers complained about low prices paid for vaccines by the CDC and other US government agencies.[133]In the early 21st century, the vaccine market greatly improved with the approval of the vaccinePrevnar, along with a small number of other high-pricedblockbuster vaccines, such asGardasilandPediarix, which each had sales revenues of over $1 billion in 2008.

POLICIES ON VACCINATION1. United StatesExemptions are typically for people who have compromised immune systems, allergies to the components used in vaccinations, or strongly held objections. All states but West Virginia and Mississippi allow religious exemptions, and twenty states allow parents to cite personal or philosophical objections. A widespread and growing number of parents claim religious and philosophical beliefs to get vaccination exemptions, and researchers have cited these exemptions as a contributing cause to an increasing number of disease outbreaks that have come from communities where herd immunity was lost due to insufficient vaccination. Supreme Court caseZucht v. King. The court decided that a school could deny admission to children who failed to provide a certification of vaccination for the protection of the public health. In 1987, a measles epidemic occurred in Maricopa County, Arizona and another court case,Maricopa County Health Department vs. Harmon, would examine the arguments of an individuals right to education over the states need to protect against the spread of disease. The court decided that it is prudent to take action to combat the spread of disease by denying un-vaccinated children back to school until the risk for the spread of measles was confirmedCurrently, in a push to eradicate Pertussis, Tetanus, Diphtheria, Polio, Measles, Mumps, Rubella, Varicella, and Hepatitis B from the population, schools across the United States require an updated immunization record for all incoming and returning students.

2. In 2006, the World Health Organization and UNICEF created the Global Immunization Vision and Strategy (GIVS). This organization created a ten-year strategy with four main goals: to immunize more people against more diseases to introduce a range of newly available vaccines and technologies to integrate other critical health interventions with immunization to manage vaccination programmes within the context of global interdependence3. Slovenia aggressive policy. While a medical exemption request can be submitted to a committee, such an application for reasons of religion or conscience wouldnt be acceptable, and isnt allowed, says Alenka Kraigher, head of the communicable diseases and environmental health center at Slovenias National Institute of Public Health. Failure to comply results in a fine and compliance rates top 95%, Kraigher says, adding that for nonmandatory vaccines, such as the one for human papilloma virus, coverage is below 50%.