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  • The first half of the 20th century

  • brought repeated outbreaks of poliomyelitis,

  • more commonly known as polio.

  • It paralyzed tens of thousands worldwide

  • and was highly prevalent in children.

  • No cure existed, so the only real hope was for a vaccine.

  • By the end of the 20th century, instances of the disease

  • had declined exponentially.

  • Today, the story of how the vaccine was developed, tested,

  • and distributed can offer numerous insights

  • into how pandemics may be combated.

  • Today, we're going to take a look

  • at what happened after the polio vaccine was developed.

  • But before we get started, be sure to subscribe to the Weird

  • History channel and let us know in the comments below what

  • other medical topics you would like to hear about.

  • OK, here we go.

  • The scientific community had been

  • working to understand the causes of polio for some time.

  • And several attempts were made at creating a vaccine.

  • Cases of polio in the United States

  • finally peaked in 1952 when 60,000 children were infected.

  • 3,000 died and thousands more were paralyzed.

  • That same year, Dr. Jonas Salk conducted

  • the first successful human trials of a vaccine

  • he and his team had developed by building

  • on the work of previous scientists.

  • In 1953, Salk showed the vaccine to his colleagues.

  • And in a nationwide address made on the CBS Radio Network

  • on March 26, 1953, Salk cautiously

  • announced his results to the world.

  • The scientist reported that the amount of antibody introduced

  • by vaccination compares favorably

  • with that which develops after natural infection.

  • Salk stated that the results gave cause for optimism

  • but warned that the objective had not yet been accomplished.

  • Shortly after the announcement, Salk

  • demonstrated his confidence in the vaccine

  • by administering it to himself, his wife, and their children.

  • And spoiler alert.

  • They were all good.

  • After Salk informed the immunization committee

  • of the National Foundation for Infantile Paralysis, or NFIP,

  • of his results, calls were made for field trials.

  • A methodology which involved one observed

  • control trial and a separate placebo-controlled trial

  • was agreed upon.

  • And groups from the United States, Canada, and Finland

  • were selected for participation.

  • More than a million first, second, and third graders

  • were given the vaccine for the observed control trial.

  • And another 750,000 were involved

  • in the placebo-controlled trial.

  • Overall, approximately 1.8 million children were involved.

  • The first to receive the vaccine injection as part of the trial

  • was a boy named Randall Kerr from McLean, Virginia, who

  • enthusiastically proclaimed, "I could hardly feel it."

  • Salk's research, which was carried out

  • at the University of Pittsburgh, was funded by the NFIP.

  • Founded by President Franklin Delano Roosevelt in 1938,

  • the organization aimed to bring together

  • researchers, educators, and volunteers

  • to combat polio, which FDR himself had contracted

  • at the age of 39.

  • The first call for donations went out

  • over the radio in January of 1938

  • when comedian Eddie Cantor told the public

  • that the March of Dimes will enable all persons, even

  • the children, to show our president that they

  • are with him in this battle against this disease.

  • He added nearly everyone can send

  • in a dime or several dimes.

  • It worked and the White House quickly

  • received nearly 2.7 million dimes.

  • The program eventually paid for trials

  • that took place in 211 countries and 44 states

  • at a cost of nearly $8 million.

  • It was so successful, in 1979, the NFIP

  • would formally adopt the name March of Dimes.

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  • In 1955, the NFIP released the results

  • of the trials which showed that Salk's vaccine was

  • 80% to 90% effective.

  • Salk for his part didn't deny that the vaccine

  • wasn't perfect.

  • But he did insist that work to improve it was continuing.

  • He held out hope that further research

  • would lead to a 100% effectiveness

  • rate against paralysis.

  • Future improvements not withstanding,

  • the trials convinced the government

  • to license the vaccine to several American pharmaceutical

  • companies.

  • And during the spring of 1955, nearly 5 million children

  • across the US received an inoculation.

  • During an interview with legendary newsman Edward R.

  • Murrow, Salk was asked about whether he

  • had patented the vaccine.

  • The scientist famously responded with a question of his own,

  • asking, could you patent the sun?

  • While the NFIP did explore the idea of patenting the vaccine,

  • they eventually concluded they didn't meet the requirements.

  • Salk himself never sought a patent, which brought him great

  • praise for what has widely been viewed

  • as a selfless act of philanthropy.

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  • In 1955, five separate labs from across the United States

  • made over four million doses of the vaccine.

  • But despite this incredible action,

  • there were still newly reported cases of paralytic polio.

  • And scientists were getting concerned.

  • An investigation showed that many of the new cases

  • had appeared in people who received

  • a vaccination from a manufacturer called

  • Cutter Laboratories.

  • And in May of 1955, Surgeon General Leonard Sheele

  • suspended all vaccinations in the US.

  • While vaccines made by Cutter were removed from the market,

  • approximately 400,000 children had already

  • been given the faulty doses.

  • Of those, 250 developed polio, which

  • was then spread to as many as 220,000 other people.

  • At least 10 died.

  • The incident led the National Institutes of Health and Public

  • Health Services to issue safety and testing standards

  • for the vaccine later the same year.

  • Vaccinations resumed in the fall of 1955.

  • But the faulty Cutter Labs vaccines

  • had left the public skeptical of Salk's formula.

  • It was at about this time that people

  • turned to the work of Dr. Albert Sabin.

  • Sabin had created an oral vaccine

  • that used an attenuated but live strain of polio

  • whereas Salk's injected vaccine used a killed virus.

  • While the NFIP financed Sabin's early research,

  • it wouldn't support large field trials in the United States.

  • So the doctor looked elsewhere.

  • In 1957, the Soviet Union granted Sabin permission

  • to conduct his field trials.

  • Over the next two years, 4.5 million people

  • in the Soviet Union as well as Malaya,

  • Mexico, Poland, and Czechoslovakia

  • would take his oral vaccine.

  • The trial showed Sabin's vaccine was safe and effective.

  • Once the news got out, medical professionals around the world

  • began to debate the pros and cons of Salk's injected vaccine

  • versus Sabin's oral vaccine.

  • Once the vaccine was widely available,

  • nations around the globe began implementing

  • their own vaccination programs.

  • The United Kingdom initiated their program in 1956

  • by offering the injected vaccine to all children

  • under 10 years of age.

  • Over time, more and more people became eligible.

  • And by 1962, after switching to the oral vaccine,

  • the UK had vaccinated most people under the age of 26.

  • Vaccinations began in Canada and Denmark in 1955.

  • Sweden and the Netherlands got started in 1957.

  • And West Germany, who had initially

  • tried a natural immunity approach,

  • began the following year.

  • By the end of the '50s, over 90 countries

  • were vaccinating their citizenry.

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  • Starting with the introduction of the Salk vaccine

  • in the 1950s, the number of polio cases in the United

  • States declined consistently.

  • By the 1960s, instances of the disease

  • numbered in the hundreds.

  • And by the 1970s, there were in double digits.

  • Studies indicated that many of these later cases

  • arose in individuals who hadn't been vaccinated

  • or hadn't completed their vaccination.

  • In 1979, the United States saw its last cases of wild polio

  • virus which presented in certain under-vaccinated religious

  • communities.

  • Once these cases were dealt with,

  • the US declared itself free of polio.

  • While the disease has occasionally

  • been brought into the country through international travel,

  • this declaration has proven mostly correct.

  • The United States is not the only country

  • to have eliminated polio thanks to large scale immunization

  • programs.

  • The UK saw its last naturally occurring

  • cases of the disease in 1984.

  • And Canada declared victory in 1994.

  • Eradicating polio worldwide was a noble goal,

  • but it wasn't entirely clear it could actually be done.

  • Many countries around the world were

  • at war, which made mass vaccination difficult, if not

  • impossible.

  • To help accomplish the goal, various international aid

  • agencies worked to broker what they

  • called days of tranquility.

  • These periods would bring cease fires

  • that could serve as national immunization days

  • where large numbers of people could receive a vaccine.

  • The Civil War in El Salvador was halted

  • for three Sundays in 1985 for such mass vaccinations.

  • During that time, 2/3 of the nation's children

  • were immunized.

  • Another national immunization day

  • took place in Lebanon in 1987.

  • Arranged by the United Nations Children's Fund or UNICEF,

  • the vaccine was made available in certain so-called corridors

  • of peace.

  • These wouldn't be the last.

  • From 1990 to 2000, days of tranquility

  • allowed mass immunizations across Eastern Europe, Africa,

  • the Middle East, Southeast Asia, South America,

  • and Central America.

  • In 1985, Rotary International initiated its PolioPlus

  • campaign.

  • According to the organization, less than half

  • of the world's children had been immunized against polio

  • at the time.

  • However, by 1992, more than 80% had received the vaccine.

  • To raise funds for distributing the vaccine,

  • Rotary worked alongside other groups

  • like UNICEF, the World Health Organization, and the Pan

  • American Health Organization.

  • And in 1988, they lobbied the World Health Assembly itself

  • for a resolution to eradicate polio.

  • Rotary International subsequently

  • became a founding member of the Global Polio Eradication

  • Initiative.

  • In the interests of combating polio, the GPEI, as it's known,

  • brings national governments together with private actors

  • like the Centers for Disease Control, the Bill and Melinda

  • Gates Foundation, and Gavi, The Vaccine Alliance.

  • Despite the fact that the World Health Organization set

  • the year 2000 as their goal for eradicating polio,

  • the fight continues to this very day.

  • Wild polio was eradicated in the Americas in 1994,

  • the Western Pacific in 2000, and Europe in 2020.

  • However, According to the GPEI, the epidemic

  • still remains in some parts of the world.

  • On the upside, in 2019, the WHO confirm the eradication

  • of type III polio virus.

  • Type II had been defeated in 2015

  • though several vaccine-derived cases have arisen

  • in Nigeria since that time.

  • Type I and vaccine-derived cases of type II,

  • however, remain widespread in both Afghanistan and Pakistan.

  • Many of these vaccine-derived cases

  • occurred because the oral vaccine, which

  • became more widely used due to its easy administration

  • and low cost, contains a live virus.

  • This means that there's a small chance of contracting the virus

  • from the oral vaccine itself.

  • How small a chance?

  • The numbers tell us it's about 1 out of every 2.5 million doses.

  • For these reasons, the oral vaccine is no longer used.

  • And as of 2019, the injected vaccine

  • is what is employed in every country.

  • Vaccines will be required until all three strains of polio

  • have been completely eliminated.

  • The GPEI continues to work toward that goal.

  • Until that mission is fulfilled, the organization

  • will continue to work towards safer vaccines and wider

  • inoculation.

  • So what do you think?

  • How long would a vaccine take to implement

  • in our current predicament?

  • Let us know in the comments below.

  • And while you're at it, check out some of these other videos

  • from our Weird History.

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What Happened After Polio Vaccine Was Developed

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    joey joey に公開 2021 年 05 月 23 日
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