- Vaccines are among the most effective inventions in medical history. The twentieth century saw the successful introduction of vaccines against diphtheria, measles, mumps, and rubella, diseases that were once major killers in developed countries. Through the use of vaccines, smallpox was eradicated and polio and measles are close to being eliminated.
- Vaccines are also among the most cost-effective tools in public health. Many infectious diseases can be prevented by vaccines that cost just a few dollars per child. The immune protection conferred by vaccines can last for a lifetime.
- Vaccines, along with the availability of improved medical care, living conditions, and sanitation, helped reduce mortality from infectious disease in the United States more than 14-fold in the 20th century.
- Infectious disease remains the second leading cause of death and the leading cause of disability-adjusted life years worldwide (one disability-adjusted life year is one lost year of healthy life).
- In 2001, approximately six million deaths were attributed to three diseases, for which no effective vaccines are available: AIDS, tuberculosis and malaria. There is ongoing research to develop vaccines for these deadly pathogens.
- HIV has infected well over 60 million people worldwide, of whom more than a third of have died.
- Resistance to antimicrobial agents has been observed in virtually all classes of organisms, resulting in diminished capacity to treat many serious infections. Vaccines can prevent such antibiotic resistant organisms.
- Edward Jenner, who discovered how to protect people from smallpox, and Louis Pasteur, who developed a vaccine to protect from rabies—are credited with being the fathers of the vaccine.
Traditional Vaccines are developed from:
- Inactivated vaccines- Produced by killing the disease-causing microorganism with chemicals or heat.
- Live, Attenuated vaccines- The disease is grown under special laboratory conditions that cause it to lose its virulence, or disease-causing properties.
- Toxoids- An inactivated toxin, the harmful substance produced by a microbe, that generates immune protection against the bacteria.
New and Second Generation Vaccine Types:
- Conjugate Vaccines
- Subunit Vaccines
- Recombinant Vector Vaccines
Common Vaccine-Preventable Diseases:
- Hepatitis A
- Hepatitis B
- Hib disease
- Pertussis (whooping cough)
- Pneumococcal pneumonia
- Rubella (German measles)