Since a 1998 article published in the medical journal The Lancet argued that childhood vaccines--specifically the measles, mumps, and rubella (MMR) vaccine--can cause autism spectrum disorders (ASD), debate has crested and fallen, ebbed and flowed. Neither the retraction of the article--partially in 2004 and fully in 2010--nor the failure of any scientist since to replicate author Andrew Wakefield's findings has dissuaded some who still believe that autism may be caused by vaccines. In fact, earlier this year a study came out reporting that parents who are hesitant to vaccinate their children--partially or entirely because of the autism fear--are rarely persuaded to change their opinions even in the face of solid scientific evidence that vaccines do not cause autism.
Study after study has been published in the intervening years confirming no link between vaccines and autism. Meanwhile, amid growing numbers of families who do not have their children vaccinated, outbreaks of measles and other preventable diseases are on the rise. This year, measles cases have reached a 20-year high, and whooping cough was declared an epidemic in California.
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.
Image: Child getting vaccine, via Shutterstock