With the virtual elimination of outbreaks of childhood diseases such as smallpox, polio and meningitis during the past century, it is surprising that the number of parents challenging recommended vaccine programs is rising. Encouraged by politicians, the media and anti-vaccine groups, more and more parents are choosing to exempt their children from vaccines.

Observers note, however, that most vaccine programs are administered with the public good in mind, with many communities requiring proper vaccination before children are allowed to enter day care or primary schools.

In a recent study of standardized records collected in Colorado from 1987-1998, the evidence was clear that risk of measles and pertussis disease was associated with philosophical and religious exemptions to immunization at both the individual and community levels. Colorado was chosen for the study because it has more than twice the national average of vaccination exemptors.

The authors reported that in 1998 among school-aged children in Colorado, the rates of exemption from immunization were 0.12 percent for medical, 0.19 percent for religious, and 1.87 percent for philosophical reasons. Their results showed:

• Children aged 3 to 18 who had exemptions from vaccination were 22 times more likely to acquire measles and nearly six times more likely to acquire pertussis than immunized children.

• In children of day care or primary school age (3-10 years), the risks were more than 60-fold greater for contracting measles and 16-fold greater for pertussis.

• The annual incidence rates of measles and pertussis among vaccinated children aged 3 to 18 were significantly associated with frequency of exemptors in that county, with the relative risks of 1.6 and 1.9 respectively.

Clearly, the critical issue is whether some parents should be allowed to pace other people's children at increased risk for disease by refusing immunizations for their own children. Vaccines still remain the most important strategy in the prevention of infectious diseases in children.

Source: Kathryn M. Edwards, MD, "State Mandates and Childhood Immunization," Journal of the American Medical Association, December 27, 2000