Autism causation and the Hepatitis B vaccine: no link
Posted Sep 15 2010 4:28pm
One of the primary subjects for those promoting vaccines as a primary cause of autism is the Hepatitis B vaccine. This vaccine is given at birth and represents a child’s first exposure outside the womb to a vaccine and, in the old days, to thimerosal. David Kirby attempted to link the rise in autism prevalence to the introduction of the HepB vaccine. Others have claimed that the rates of special education placements are 9 times higher amongst children given the HepB vaccine at birth. Here is the abstract for ( Hepatitis B triple series vaccine and developmental disability in US children aged 1–9 years rel=”nofollow”)
This study investigated the association between vaccination with the Hepatitis B triple series vaccine prior to 2000 and developmental disability in children aged 1– 9 years (n¼1824), proxied by parental report that their child receives early intervention or special education services (EIS). National Health and Nutrition Examination Survey 1999–2000 data were analyzed and adjusted for survey design by Taylor Linearization using SAS version 9.1 software, with SAS callable SUDAAN version 9.0.1. The odds of receiving EIS were approximately nine times as great for vaccinated boys (n¼46) as for unvaccinated boys (n¼7), after adjustment for confounders. This study found statistically significant evidence to suggest that boys in United States who were vaccinated with the triple series Hepatitis B vaccine, during the time period in which vaccines were manufactured with thimerosal, were more susceptible to developmental disability than were unvaccinated boys.
The recent study on thimerosal and autism gives us a look at how the Hepatitis B vaccine might (or might not) be linked to autism. Exhibit 16.1 on page 82 of volume 2 of the technical report is a graph of HepB vaccine uptake amongst autistic children (AD) and non-autistic children (controls)
Here is that exhibit, showing the total number of vaccines (count) and amount of thimerosal (amt) for all vaccines and for HepB alone:
The top right graph shows the number of HepB vaccines for autistic kids (solid line) and non-autistic kids (dotted line). They are, to all intents and purposes, the same.
Take a look at the birth dose. Not every kid got it. Maybe about 1/2 got the birth dose at birth, and about 2/3 got it within the first few days.
If the birth dose of HepB caused autism to any significant degree, I would expect to see a higher percentage of autistic kids than non-autistic kids getting that shot. It just didn’t happen. Take a closer look at that graph :
The same percentage of got the HepB shots—all 3 of them—as non-autistic kids.
Still wondering about that birth dose? Let’s zoom in on the graph:
Those lines are right on top of each other.
The HepB hypothesis won’t go away. Just like the thimerosal hypothesis or the MMR hypothesis. Just today, Mark Blaxill and Dan Olmsted put out a very long post at the Age of Autism blog pushing the idea. They use the bad and worse studies from Thoughtful House on infant macaques to bolster their arguments.
The funny thing about evidence is, some people never accept it.