Abstract
The issue of vaccines and autism has attracted a lot of attentionwithin medical circles. There are controversies in relation to the link between the two. Different people have varied opinions about this topic. Some claim there is an explicit relationship, while others oppose such arguments.
In this paper, the author sought to clarify the issue by analyzing existing evidence regarding the effects of vaccines. Information used was sourced from population studies, scientific consensus, and other independent research by individuals. It was made clear that autism has nothing to do with vaccines. Individuals who support this assertion rely on flawed research findings. Thimerosal, which is present in many vaccines, was critically scrutinized in this study.
The preservative is said to contain mercury, which is poison in itself. As a result of these concerns, the compound was removed from some vaccine products. Many people have questioned the rationale for this elimination. Findings made in studies carried out on measles, mumps, and rubella vaccines were analyzed and the relationship between autism and these drugs was found to be non-existent.
Vaccines and Autism: A Critical Analysis of Thimerosal in Relation to Measles, Mumps, and Rubella
The safety and efficacy of vaccines has been the subject of many studies in the medical field. The drugs are believed to be the causal agents behind a number of medical disorders. Most of these drugs are administered to children on a routine basis as part of post-natal care. As a result, their safety must be enhanced for the sake of these consumers.
Before a vaccine is put into commercial use, tests to verify its safety are carried out. The tests are conducted on human population to check for any side effects (Department of Health and Human Services, National Institutes of Health & National Institute of Child Health Development [DHHS, NIH & NICHHD], 2001.)
Uncertainties over the relationship between vaccines and autism have dominated many studies. The use of measles, mumps, and rubella (MMR) vaccines and autism has attracted the attention of many scholars.
According to Wakefield (2010), autism is a disorder that inhibits neural development. Wakefield asserts that the symptoms associated with this condition appear before the child attains the age of 3 years. The current study revolves around this issue. In this paper, the author analyzes various studies that highlight the relationship between vaccines and autism.
Autism
The medical condition is exhibited through various forms of mental and cognitive impairments. Social interaction is one of the cognitive abilities affected by this disorder. Autistic children find it hard to interact with other people around them. Such children are affected by significant impairments with regards to verbal and non-verbal communication.
Other traits associated with these patients include repetitious and stereotypic behavior patterns. Causes of this disorder are varied. They include genetic, cognitive, and neural factors. Other people have linked autism to vaccines and thimerosal preservatives (Wakefield, 2010).
Thimerosal is found in many vaccines manufactured from the 1930s, including those used in MMR. The climax of the alleged negative effects of this preservative was seen in 1999. Manufacturers were forced to remove the substance from their products, but not entirely. For example, traces of this chemical are still present in inactivated influenza vaccines (Wakefield, 2010).
The issue of this substance and its effects on children has stoked fears among parents, doctors, vaccines manufactures, and the media. In attempts to scrutinize the veracity of these allegations, dozens of studies have been conducted in this area.
Studies on Measles, Mumps, and Rubella Vaccines
Available studies have not established any link between vaccine and autism. According to Wakefield, “natural measles is a virus known to cause respiratory diseases and brain damage…” (2010, p. 37). Vaccines are used to counter this condition. There is no evidence to suggest that autism may arise from complications brought about by wild measles.
The strain of this virus is weakened by the measles vaccine. According to Wakefield, thimerosal, the compound found in most vaccines, “…is mercury, which is preservative in nature” (2010, p. 48). Mercury components do not exist naturally in the body. When ingested in large quantities, the compounds may cause brain damage. Such scholars as Wakefield assert that the amount of mercury present in vaccines is not enough to cause brain damage.
Stratton (2001) and Wakefield (2010) carried out independent studies to find the association between measles vaccine and autism. In their research, they found measles virus among the children in their study. The participants with this virus also had two other conditions. They had gastrointestinal disorders and autism. The studies involved 25 autistic children.
A control group of 13 young patients with gastrointestinal disorder (but without autism) was used. The disorder was observed in one participant from each of the cohorts in the experiment. In their conclusion, Stratton and Wakefield claimed that the experiment provided substantial evidence against any relationship between autism and MMR.
Another study was conducted in the UK. It was titled Measles Vaccinations and Antibody Response in Autistic Spectrum Disorders (ASD). The experiment group consisted of 98 vaccinated children between the ages of 10 and 12 years. The control group was made up of 52 children in the same age bracket.
The latter cluster involved participants with special needs. However, these childnre were not suffering from ASD. Another group of 90 ‘normal’ children was also used. It was established that there were no significant differences between autism and response to antibody control doses (Stratton, 2001).
The Thimerosal Controversy, Vaccines, and Autism
The media has contested the use of thimerosal preservative in drugs, including vaccines. The controversy revolves around the allegation that vaccines with mercury components result in autism and other brain disorders. However, scientific consensus is of the opinion that there is no evidence to support these allegations. In their view, Wakefield opines that “vaccine and autism association is the most damning medical hoax of the century” (2010, p. 34).
According to Wakefield, “thimerosal is an agro-mercury compound containing preservatives” (2010, p. 71). The substance has been used for the past 8 decades to avert fungal and bacterial infections in vaccines. The Centre for Disease Control and Prevention (CDC) issued directives to manufacturers of these drugs advising them to stop using the preservative. The move was purely precautionary. The compound was eliminated from most vaccines manufactured in the USA and Europe. As a result of this move, parents had reasons to believe that the compound caused autism (DHHS et al., 2001).
The possible effects of thimerosal have been analyzed by many professionals. Most scientific findings indicate that there is no relationship between autism and thimerosal. For instance, studies have established that the symptoms of mercury poisoning are very different from those of autism. In addition, the prevalence of autism is still high in spite of the eradication of mercury from vaccines (DHHS et al., 2001).
Scientific organizations and other renowned medical bodies have refuted the claim that the two concepts are related. Officials in these agencies claim that their studies have not found any connection between thimerosal and autism. In spite of this consensus, some people still contend that the preservative has direct link to autism (Schreibman, 2005).
Wakefield is of the opinion that “…continued increase in autism is (as a result of) the prevailing controversies” (2010, p. 42). Parents are reluctant to treat their autistic children with the correct and proven medications. Instead, they have opted for dangerous forms of treatments. In addition, parents are erroneously discouraged from vaccinating their children due to the fear of thimerosal toxicity.
As such, the resources needed to conduct research on the best form of treatment for autism are diverted to other areas. Based on this, it is fallacious to claim that vaccines cause this condition.
Population Studies, Autism, and Vaccines
The reviews are very important in the management of pandemics. As already indicated, many studies have been carried out on children to explain the link between vaccines and medical disorders. From the findings made in most of these surveys, it has been established that there is no substantive evidence to support the alleged link between autism and Thimerosal-Containing Vaccines (TVCs).
Studies that have been conducted after the removal of TVCs indicate that the prevalence of autism has not changed significantly. However, an epidemiological inquiry by Mark Geier reported an association between the two variables. A review of this report by independent scholars has not established evidence to the contrary (Schreibman, 2005).
A study was carried out on 467,450 children in Denmark to investigate the issue. The experiment established no link between TVCs and ASDs. The researchers also revealed that there was no dose-response relationship to indicate exposure to thimerosal and autism. Ecological correlation was carried out and an analysis of 956 Danish autistic children found no relationship between the two phenomena (Schreibman, 2005).
In the UK, historical cohort studies comprising of 109, 863 children were carried out. In these surveys, there was no direct link between TVCs and autism. However, potential increase in ‘tics’ was reported. Tic is a sudden muscle movement that cannot be controlled. It is repetitious and non-rhythmic. It involves motor movement.
Common examples include blinking of the eyes and clearing the throat. Another research established that the benefits of vaccines outweigh the costs linked to them. However, it should be noted that the studies carried out in the UK involved the use of Diphtheria Tetanus Pertussis (DTP). The vaccines are irrelevant in the US since they involve the use of thimerosal preservatives (Schreibman, 2005).
Other studies were carried out in Canada. One such survey comprised of 27,749 children. It was established that there was no correlation between thimerosal and Pervasive Development Disorder (PDDs). Autism is one of the five PDDs. It was established that the disorder is not associated with thimerosal preservative. On the contrary, the study found that PDDs were high among children who were vaccinated with non-TCVs (Schreibman, 2005).
Additional studies carried out in the US confirm that there is no relationship between thimerosal and autism. A review of 78,829 children from Health Maintenance Organization (HMO) affirmed this position. A research carried out in California noted that the removal of thimerosal from vaccines did not reduce the escalation of autistic disorders. As such, scholars established that thimerosal was not the causal agent of autism (Schreibman, 2005).
Scientific Consensus, Autism, and Vaccines
The National Academic of Sciences (NAS) and Institute of Medicine has established a panel of experts to ensure that the safety measures with regards to immunization are fully implemented. In the initial findings, the evidence collected by the panel was not enough to accept or reject the association between autism and thimerosal. However, a possible link was accepted on the grounds that it is biologically plausible (Geschwind, 2009).
Scientific consensus is based on reports from medical studies carried out to establish whether or not there is a link between autism and vaccines. The scientific committee mentioned above approached the issue from a theoretical perspective before reviewing in vitro and population analyses.
The explanation was simple for those in favor of in vitro or animal approach. Geschwind is of the opinion that “it is provocative to assert that experiments exhibiting effects of thimerosal on biochemical pathways in cells culture systems were associated with people with autism” (2009, p. 39). The scientific body refuted the claims that abnormalities occurring in the immune systems are associated with autism. In their conclusion, the group refuted any causal association between TCVs and autism.
Court Cases
In 1986, a vaccine court was established to deal with injuries associated with this medical practice. The institution was founded by a National Childhood Vaccine Injury Act (NCVIA). It was a reaction to a DPT vaccine scare in the early 1980s. Parents of children suffering from autism have filed lawsuits citing TCVs as the causal agent. So far, only one out of the 5,632 cases has received compensation. Slightly over 738 cases have been dismissed by the courts, while the others are pending (Kirby, 2005).
In the case that was compensated, the bench unanimously voted for the payment after it was established that the child suffered from a pre-existing mitochondria disorder. After many vaccinations, the child exhibited autism-like symptoms, including thimerosal. The rationale for payment was based on the mitochondria disorder. CDC officials warned against this judgment. They claimed that not all autistic cases portray this defect (Kirkland, 2012).
In 2009, the court passed judgments on other matters brought before it. Plaintiffs in 3 of the cases were confident about the alleged association between TCVs and autism. However, a bench comprising of three judges independently established that there was no substantive evidence linking the two issues. The plaintiffs were denied compensation. The cases formed the basis of other autistic-related legal battles. The chances of compensation in the pending cases have significantly diminished (Kirkland, 2012).
Conclusion
The author of this paper affirmed that the association between autism and vaccines is baseless. Scholars in this field should embark on research to establish the real cause of this disorder. In the studies cited in this paper, there was no evidence to back this link. The removal of thimerosal from vaccines was a precautionary move. It was instigated by the realization that mercury is poisonous when taken in large quantities. It is erroneous to link mercury poisoning to autism given the fact that the symptoms associated with the two are very different.
References
Department of Health and Human Services, National Institutes of Health, & National Institute of Child Health and Human Development. (2001). Autism and the MMR vaccine. Rockville, MD: U.S. Government Press.
Geschwind, D. (2009). The vaccine-autism controversy. Nature Medicine, 15(992), 992.
Kirby, D. (2005). Evidence of harm: Mercury in vaccines and the autism epidemic: A medical controversy. New York: St. Martin’s Press.
Kirkland, A. (2012). The legitimacy of vaccine critics: What Is left after the autism hypothesis?. Journal of Health Politics, Policy and Law, 37(1), 69-97.
Schreibman, L. (2005). The science and fiction of autism. Cambridge, Mass: Harvard University Press.
Stratton, K. (2001). Immunization safety review: Measles-mumps-rubella vaccine and autism. Washington, D.C.: National Academy Press.
Wakefield, A. (2010). Callous disregard: Autism and vaccines- The truth behind a tragedy. New York: Skyhorse Publishers.