With the number of vaccines offered today, some parents wonder whether children receive too many immunological components that overwhelm the immune system. Do children encounter more immunological components from vaccines today than in the past? The simple answer is no.
To answer the question about the number of immunological components from current vaccines, one must look at the history of vaccines. At the beginning of the twentieth century, children received one vaccine, the smallpox vaccine. During the 1960s, children received five vaccines and as many as eight shots for diphtheria, pertussis, tetanus, polio, and smallpox by the age of two. During the 1970s and 1980s, children received vaccines that protected against seven diseases: measles, mumps, rubella, diphtheria, tetanus, pertussis, and polio. Children now receive eleven vaccines and as many as twenty shots by the age of two that protect against fourteen diseases such as diphtheria, pertussis, tetanus, polio, measles, mumps, rubella, chickenpox, hepatitis B, rotavirus, and haemophilus influenzae type B.
Despite the increase in the number of vaccines received, children nowadays receive fewer immunological components because the number of immunological components in vaccines has dramatically decreased. At the beginning of the twentieth century, the smallpox vaccine contained about 200 immunological components. Thirty years ago when children received just seven vaccines, all seven combined contained a little more than 3,000 immunological components. Today, despite the eleven vaccines that protect against fourteen diseases, children receive a total of fewer than 160 immunological components.
Why do current vaccines contain fewer immunological components than in the past? Since the advent of the modern vaccine, scientific advances have allowed for the creation of purer and safer vaccines. The improvement in vaccines has resulted in the need for fewer and fewer immunological components in each vaccine. Therefore, although children do receive a greater total number of vaccines than in the past, the total amount of immunological components in all vaccines received is significantly less now than even just thirty years ago. The number of vaccines given is not as important as the number of immunological components contained in the vaccines.
Furthermore, the number of immunological components to which children are exposed through vaccines is miniscule compared to the amount of germs (viruses, bacteria, parasites, fungi) to which children are exposed through day to day living. Upon exiting the sterile environment of the womb, a baby is colonized with trillions of bacteria. Each bacterium contains between 2,000 and 6,000 immunological components. In addition to bacteria, children are also faced with viruses, parasites, and fungi that contain immunological components on a daily basis. The total amount of immunological components in all vaccines is insignificant compared to the immunological components to which children are exposed in daily living.
To make a long story short, no, children do not receive too many immunological components from vaccines.
Addressing Parents’ Concerns: Do Multiple Vaccines Overwhelm or Weaken the Infant’s Immune System?: http://www2.aap.org/immunization/families/overwhelm.pdf
Refusing, Delaying, And Alternating The Vaccine Schedule: Helpful Or Harmful? Part 2: http://www.texaschildrensblog.org/2011/11/refusing-delaying-and-alternating-the-vaccine-schedule-helpful-or-harmful-part-2/
Too Many Vaccines? What You Should Know: http://www.chop.edu/export/download/pdfs/articles/vaccine-education-center/too-many-vaccines.pdf
Oral Polio Vaccine in India: http://commons.wikimedia.org/wiki/File:Vaccination-polio-india.jpg