Fast Five Quiz: Are You Ready to Face Back-to-School Health Concerns?

Germaine L. Defendi, MD, MS


August 19, 2014

According to the Centers for Disease Control and Prevention (CDC), the vast majority of states require a second dose of the MMR vaccine before school admission. Proof of vaccination varies from state to state, but parental confirmation of vaccine administration is not accepted.

The first dose of the MMR vaccine is administered to a child older than 12 months (recommended age, 12-15 mo). This initial dose induces protective immunity in 95% of recipients. Because measles virus is highly contagious, the remaining 5% susceptible population is sufficient to sustain periodic outbreaks in otherwise highly vaccinated populations.

A second dose of vaccine, typically administered between the ages of 4 and 6 years, is now recommended for all school-aged children in the United States. It induces immunity in about 95% of the 5% who did not respond to the initial dose. If the recommended schedule for the MMR vaccination must be altered, a minimal interval of 4 weeks between receiving the first and second doses is required.

The CDC reported that 1.8% of kindergartners have a vaccine exemption for any reason. Vaccine refusal has been linked to several outbreaks of preventable diseases, such as measles outbreaks in Ohio and New York in 2014.

For more on vaccination against measles, read here.


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