Autism is Not Caused by Vaccines: A Response to Jenny McCarthy and Jim Carrey's Article.
Autism has become a major issue for modern parents, affecting 1 in 150 children, and can be linked to a number of exposures, including vaccines, according to a piece written last year by actress Jenny McCarthy and actor Jim Carrey and published in the New York Times (McCarthy, Carrey, 2008). Unfortunately, although some legitimate sources are cited, including statistics from the CDC, McCarthy's article uses mostly supposition and anecdotal evidence to support her arguments that vaccines "play a major role" in the development of autism. McCarthy and Carrey have apparrently had success in reversing many of their son's autism symptoms through "starting a gluten-free, casein-free diet, vitmain supplementation, detox of metals, and anti-fungals for yeast overgrowth that plagued his intestines" (McCarthy, Carrey, 2008). While they do make an excellent point that physicians that they have seen after this improvement have not investigated the factors in his recovery, an action that could potentially lead to more understanding of the disease, the improvements could be due to any one of their interventions, behavioral or cognitive therapy, or a combination of factors.
Although it is true that Autism rates have risen in recent years and is a major health problem, it is imperative to use information derived from reliable sources before rushing to stop vaccinations, an intervention that saves countless lives. The Wakefield paper published in 1998 that began the popular notion that autism is caused by vaccines was only a case series, where 12 children who were observed to have developed intestinal problems within a month of the MMR vaccine, and 8 of whom were also diagnosed with autism at that time ("A Look at What Causes", 2008). While there may be a correlation, this does not denote causation, and along with the small sample size and type of study, this paper should not be used to base any conclusions on, only the possibilty of future research. Other studies are currently looking at biochemical contributors for autism that may lead back to an environmental cause (Deth, Muratore, Benzecry, Power-Charnitsky, & Waly, 2008; Van Den Hazel, Zuurbier, Babisch, Bartonova, Bistrup, Bolte, et al., 2006), and the CHARGE Study is an ongoing large-scale case-control study investigating a wide array of possible environmental and genetic factors into the development of autism and hopes to uncover some statistically significant causational factors (Hertz-Picciotto, I., Croen, L., Hansen, R., Jones, C., Van De Water, J., & Pessah, I., 2006).
There is much epidemiologic work to be done in the search for causes of the autism epidemic. Although it is good to have these types of issues brought to the attention of the public through media, much of the media information and hype is innaccurate. In this case, because of celebrity status and media attention, McCarthy and Carrey write a heartfelt and well-intentioned piece that is presented by lay-people without the epidemiologic background to properly interpret and synthesize the current data on autism and it's contributors. This lack of scientific rigor and support in many popular media outlets unfortunately is not uncommon and spreads innacurate and potentially harmful information.
Deth, R., Muratore, C., Benzecry, J., Power-Charnitsky, V., & Waly, M. (2008). How environmental and genetic factors combine to cause autism: A redox/methylation hypothesis [Abstract]. NeuroToxicology, 29(1), 190-201. Retrieved May 10, 2009 from the EBSCO Database.
Children's Hospital of Philadelphia Vaccine Education Center. (2008) A Look at What Causes, and What Doesn't Cause, Autism. Retrieved on May 9, 2009 from: http://www.chop.edu/consumer/jsp/division/generic.jsp?id=84662#other_studies .
Hertz-Picciotto, I., Croen, L., Hansen, R., Jones, C., Van De Water, J., & Pessah, I. (2006). The CHARGE Study: An Epidemiologic Investigation of Genetic and Environmental Factors Contributing to Autism. Environmental Health Perspectives, 114(7), 1119-1125. Retrieved May 10, 2009
McCarthy, J., Carrey, J. (2008, April 4). Jenny McCarthy: My son's recovery from autism. CNN.com. Retrieved on May 8, 2009 from: http://www.cnn.com/2008/US/04/02/mccarthy.autsimtreatment/ .