According to a new study, vaccines containing the preservative thimerosal administered to macaque monkeys did not produce the same brain and behavioral changes that are linked to autism. The vaccines were administered to the monkeys based on the same schedule pediatricians used in the 1990s.
The Los Angeles Times reported that the researchers also gave a wide range of vaccines which included the MMR vaccine (measles, mumps, and rubella) — which never contained thimerosal — to the monkeys. Again, no evidence of brain changes or behavior were present to suggest that the MMR vaccine or any other vaccine combination can trigger autism.
This latest research comes on the heels of California’s mandatory vaccine bill SB277, which was signed into law early this summer – much to the dismay of anti-vaccine groups who still disseminate long-debunked claims about the harm vaccines allegedly cause.
From the Times:
The latest research, published Monday in the journal PNAS, casts further doubt on a suspected link between autism and vaccines, which has fueled widespread resistance to vaccinations currently recommended for American children. So far in 2015, 189 people in the United States have contracted measles in a series of outbreaks that the Centers for Disease Control and Prevention has linked to low vaccination rates in communities scattered across the country.
Suspicion that a link between autism and vaccines (particularly those containing the preservative thimerosal) persists despite a notable absence of proof. Since 2003, nine studies conducted or funded by the CDC have found no link between vaccines containing thimerosal and autism spectrum disorder, nor any link between the MMR vaccine and the neurodevelopmental disorder.
The research of Andrew Wakefield, the British physician who purported to establish such a link in 1998, was found to have been fraudulent and in 2010 Wakefield was stripped of his white coat in Britain.
“This study is one more piece of evidence that shows that the schedule created by CDC and recommended by the American Academy of Pediatrics is a very safe schedule to protect children from specific diseases, at the specific times when they’re most vulnerable,” Dr. Tanya Altmann, a Calabasas pediatrician and assistant clinical professor at UCLA’s Mattel Children’s Hospital told the L.A. Times.
The mercury that was present in the preservative thimerosal used for childhood vaccines was mostly phased out in 2001, although it’s still used in some influenza and meningitis vaccines. The vaccine against diptheria, tetanus and pertussis still contains trace amounts of the substance.
For the study, the 79 infant rhesus macaques were used because their physiology and brain development closely resemble those of human babies.
Featured image via Flickr