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Another disease that has been eliminated from the US is [[Polio]], which killed over 3,000 people in the United States in 1952,<ref>http://www.cdc.gov/nchs/data/vsus/VSUS_1952_2.pdf</ref> and afflicted such noted persons as President [[Franklin Delano Roosevelt]], actor Alan Alda, and musician Itzak Perlman. When doctors began using a vaccine to fight polio, it practically eradicated the disease in the developed world.<ref>https://www.cdc.gov/polio/progress/index.htm</ref>

Another disease that has been eliminated from the US is [[Polio]], which killed over 3,000 people in the United States in 1952,<ref>http://www.cdc.gov/nchs/data/vsus/VSUS_1952_2.pdf</ref> and afflicted such noted persons as President [[Franklin Delano Roosevelt]], actor Alan Alda, and musician Itzak Perlman. When doctors began using a vaccine to fight polio, it practically eradicated the disease in the developed world.<ref>https://www.cdc.gov/polio/progress/index.htm</ref>

The incidence of other diseases such as [[diphtheria]], [[pertussis]], and [[measles]], has decreased greatly since the invention of vaccines against these diseases.<ref>https://www.unicef.org/pon96/hevaccin.htm</ref>

The incidence of other diseases such as [[diphtheria]], [[pertussis]], and [[measles]], has decreased greatly from improvements in sanitation, increased awareness of the benefits of hand-washing and other preventive measures, and the invention of vaccines against these diseases.<ref>https://www.unicef.org/pon96/hevaccin.htm</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 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 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>