Measles and MMR vaccines: benefit or risk?
Measles is a serious and highly contagious infection. However, strong scientific evidence shows that both the measles vaccine and the combined measles-mumps-rubella (MMR) vaccine virtually eliminate the risk of measles.
In recent years, there has been speculation that the measles and MMR vaccines may increase a child’s risk of developing autism—a pervasive development disorder. Research published in the June 2002 issue of Clinical Evidence , a publication of the BMJ Publishing Group, found no evidence that either vaccine is associated with an increased risk of autism.
About the study
In November 2001, researchers in the United Kingdom (UK) conducted a detailed search of the world's scientific literature on measles/MMR vaccines and autism. Their search also included national and international policy documents and data from the World Health Organization, United States Centers for Disease Control and Prevention (CDC), and the UK Public Health Laboratory Service.
The researchers evaluated the quality of each study and the reliability of the findings. Quality of a study is based on factors such as:
- The numbers of participants
- How participants were selected and assigned to treatment groups
- If a control group of healthy people was used for comparison
- If a placebo (inactive treatment) was used in the control group
- If the researchers measured and controlled for various factors, other than the factor of interest, that may influence the study results
- How the data were analyzed
Finally, they weighed the evidence from all of the studies.
As expected, the researchers found that the measles and MMR vaccines are extremely effective at preventing measles infection, with rates between 95% and 100%.
When considered together, the available research indicates there is no link between the vaccines and the development of autism. Although, there has been a rise in the number of autism cases diagnosed, this rise has not coincided with an increase in vaccination.
The research does show that these two vaccines are associated with an increased risk of moderate to high fever within three weeks of vaccination. However, this fever resolves on it’s own and is less severe than the high fever that occurs in 100% of measles infections.
Although these results are interesting, there are limitations to this study. The researchers collected data from numerous studies in an attempt to derive an overall assessment of risk. Because studies are designed differently, this method lacks a certain degree of precision, though it does help synthesize data from many similar studies.
How does this affect you?
Is it safe for your child to get the measles or MMR vaccine? Yes. These findings provide further evidence of the safety and effectiveness of these vaccines. Although a small number of children may get a self-limiting fever after vaccination, people who contract the measles become very ill and some who contract measles, mumps, or rubella die.
The CDC recommends that children receive the MMR vaccine once at 12 to 15 months old and again between ages 4 and 6 years.
Does this mean that children who receive the measles or MMR vaccine will not develop autism? Not necessarily. Autism is a poorly understood condition for which no cause has been identified, so there is no way to predict which children will develop autism.
Donald A and Muthu V. Measles and Child Health. Clinical Evidence . 2002;7:331-340.
Last reviewed June 14, 2002
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © 2007 EBSCO Publishing All rights reserved.