We Don’t Know Enough About Childhood Vaccines

By Margaret Dunkle

Researcher asks:  Are 36 doses of vaccine before age 2 too much, too little, or just right?

The topics of vaccines and vaccine safety spark emotional outbursts at scientific meetings and family dinner tables alike. But many of these debates are remarkably fact-free. Surprisingly few people — not just concerned parents but also doctors, policymakers and even immunization experts — can answer this seemingly simple question: How many immunizations does the federal government recommend for every child during the first two years of life?

The answer is important because most states, including Maryland, faithfully follow the recommendations of the federal Centers for Disease Control and Prevention, codifying CDC guidelines into requirements for children to enroll in school, kindergarten, preschool and child care.

A new Journal of Toxicology and Environmental Health study reports that the higher the proportion of infants and toddlers receiving recommended vaccines, the higher the state’s rate of children diagnosed with autism or speech-language problems just a few years later. This analysis is sure to rekindle the debate about vaccine safety.

For that conversation to produce useful results, we must start by defining terms. A “dose of vaccine” refers to each vaccine or antigen given to increase immunity against one specific disease. For chicken pox, a child receives one dose of vaccine through one shot.

By contrast, an “immunization event” refers to each separate administration of a vaccine or bundle of vaccines — through a shot, orally, or nasally. The MMR shot for mumps, measles and rubella involves three doses of vaccine but is one immunization event.

The critical number is how many doses of vaccine a child receives. Why? If a vaccine is strong enough to confer immunity against a disease, it is important enough to count separately.

Clear definitions, analysis of CDC’s “General Recommendations on Immunization,” and confirmation by Dr. Andrew Kroger, lead author of the definitive report on these recommendations, produce the answer to the not-so-simple-after-all question posed above.

Read the entire article here.