Childhood Vaccines Vindicated Once More
No link to autism found in large review of previous research on measles, mumps, rubella vaccine
By Dennis Thompson
TUESDAY, July 1, 2014 (HealthDay News) -- Parents worried about getting young children vaccinated against infectious diseases have fresh cause for reassurance, researchers say.
A new review of existing scientific evidence has concluded that childhood vaccines are safe and don't cause serious health problems such as autism or leukemia.
"Our findings support that vaccines are very safe for children, and add to a substantial body of evidence that the benefits of vaccination outweigh the very low risks," said senior author Dr. Courtney Gidengil, an associate physician scientist at RAND Corporation and an instructor at Harvard Medical School. "Hopefully, this will engage hesitant parents in discussions with their health care providers."
The review found strong evidence that the MMR (measles, mumps and rubella) vaccine is not associated with autism, which is consistent with previous reviews of this rumored link.
Some parents have chosen not to have their children vaccinated because of a now-debunked and retracted study published in 1998 that suggested that the MMR vaccine might cause autism. It was later reported that the study's author, Dr. Andrew Wakefield, had altered some of the study's results.
The researchers behind the new study also found no link between childhood leukemia and vaccines for MMR, DTaP (diphtheria, tetanus and pertussis), tetanus, influenza and hepatitis B.
Overall, vaccines given to children 6 or younger are safe, causing few side effects, the review concluded. The findings are published in the July 1 online edition and the August print issue of the journal Pediatrics.
"We found that the serious adverse effects linked to vaccines are extremely rare," said lead author Margaret Maglione, a policy analyst at RAND Corporation.
These findings should provide solid support for pediatricians and family physicians in their discussions with parents about the benefits and risks of immunization, said Dr. Carrie Byington, a professor of pediatrics and vice dean of academic affairs and faculty development at the University of Utah College of Medicine.
In an accompanying editorial, Byington noted recent medical school graduates have reported themselves more skeptical of the safety and effectiveness of vaccines than did older graduates.
"I'm hopeful younger physicians who have not seen the devastating vaccine preventable infections may see the data and strengthen their will to communicate the importance of vaccines to parents," Byington said.
Doctors struggle to maintain a vaccination rate high enough to prevent outbreaks, researchers said in background material. Parents refusing to have their children vaccinated has contributed to recent outbreaks of preventable diseases like measles and whooping cough.
"Should more and more people choose not to vaccinate their children, we're going to see more and more stories like these," Gidengil said.
The U.S. Agency for Healthcare Research and Quality hired RAND Corporation to review the safety of vaccines recommended for children, adolescents, adults and pregnant women.