Vaccines Are Effective

Vaccines have saved millions of lives.

The numbers tell the story: Vaccines save lives. Scientists widely consider immunization to be one of the greatest public health achievements of the 20th century, and experts and medical science and research agree that timely immunization is vital to staying healthy.

The Centers for Disease Control and Prevention estimates that for children born in the U.S. from 1994 to 2013, vaccination will prevent an estimated 322 million illnesses, 21 million hospitalizations and 732,000 deaths over the course of their lifetimes.

Vaccines have dramatically changed medicine over the last century. Before vaccines, parents in the United States could expect that every year:

  • Polio would paralyze 10,000 children.
  • Pertussis (whooping cough) would kill 8,000 infants.
  • Measles would infect about 4 million children, killing about 500.
  • Rubella (German measles) would cause birth defects and intellectual disabilities in as many as 20,000 newborns.
  • Diphtheria would be one of the most common causes of death in school-aged children.
  • A bacterium called Haemophilus influenzae type b (Hib) would cause meningitis in 15,000 children, leaving many with permanent brain damage.

Vaccination has decreased the rate of disease dramatically.

Vaccines have reduced and, in some cases, eliminated many diseases that killed or severely disabled people just a few generations before. For most Americans today, vaccines are a routine part of health care.

Disease Baseline 20th Century Annual Cases 2015 Cases* Percent Decrease
Measles 503,282 188 99.9%
Diphtheria 175,885 0 100%
Mumps 152,209 1,308 99%
Pertussis (Whooping Cough) 147,271 20,679 87%
Smallpox 48,745 0 100%
Rubella, less than 6 years old 47,745 6 99.9%
HiB, less than 5 years old 20,000 < 50 99.9%
Polio 16,316 0 100%
Tetanus 1,314 30 97.7%

*Source: World Health Organization, 2015 counts are provisional

These drops in disease rates are primarily the result of people getting vaccinated, and not because of improved sanitation conditions or hygiene.

The diseases we vaccinate against have declined, but they haven’t disappeared. Other countries don’t have the same access to vaccines as the United States. As we have seen in the United States and in other countries, if we stop vaccinating, vaccine-preventable diseases can and will return. This is why we still vaccinate against diseases we no longer see in our country. If the majority of our country stopped vaccinating, one infected traveler from another country where a disease hasn’t been eliminated could potentially spark an outbreak.

Disease elimination and reduction by vaccines in the U.S.
Source: Data from the Journal of the American Medical Association

Have questions? Visit our FAQ section.

Children’s Hospital of Philadelphia: Vaccine Details
Immunize for Good: Benefits vs. Risks
Children’s Hospital of Philadelphia: Vaccine Developments, History by Year