Abstract

Autism is a mental condition that affects thousands of children every year across the United States. The condition is shown to affect certain areas of the brain responsible for mental, social, and cognitive behavior of the human body. Those who suffer from this disease are given treatment; although, no cure has been established. The concern for this disease stems from common knowledge that the disease is also very rare in identifying and its cause is unknown. Within the late 1990s up until today, a study conducted by Dr. Andrew Wakefield, a gastroenterologist and medical researcher based in the United Kingdom, have sparked the debate whether vaccinations are a factor in the development of autism, causing a trend of refusal of vaccinations up to this day. Due to this anti-vaccination sentiment, research has been conducted and evaluated to prove whether or not the correlation between autism and vaccine actually exist.

Introduction

As of today, it is known that vaccinations are a key component in the development of the human body and maintaining one’s health. Vaccines are known as substances that contain a weakened or dead form of the target disease that is used to build the body’s immunity. In 1998, a study conducted by Dr. Andrew Wakefield, a gastroenterologist and medical researcher, was published in the Lancet Journal in the United Kingdom. In this journal article, Dr. Wakefield examined 8 patients in total, all children, who were diagnosed as having autism like symptoms after being vaccinated for MMR (Also known as measles, mumps, and rubella). The release of the article held mixed reactions, with the creation of the anti-vaccination sentiment that had been established in the United Kingdom, and making its way to the United States, even though hence research was based in another country. However, the research done by the British doctor would later be invalidated, resulting in Dr. Wakefield having his license revoked and having his research written off as fraudulent. Even so, studies against the statement of vaccinations causing autism have been little to none conducted on disproving this ideology. This concept is held at an all time high in being a danger to the public health, as refusal to vaccinate children over an inaccurate study can lead to the return of diseases that may become harmful and widespread in a short amount of time. As of today, there have only been a few studies conducted on actual research focusing on the biological component on how immunizations work throughout the body. Majority of the studies use surveys and other journals in order to make a conclusive argument against the connection between vaccines and autism.

Methods

As discussed, the vast amount of studies on vaccinations are based on evaluating past studies and comparing them together in order to come to a conclusion on whether or not autism is directly related to the usage of vaccines. One of the first articles on the study on why vaccines aren’t used is Parent-Reported Reasons for Nonreceipt of Recommended Adolescent Vaccinations, National Immunization Survey, published in 2009 by the National Center for Biotechnology and Information. Authors Christina Dorell and David Yankey wanted to identify the reasons as to why there was a lack of vaccination among teenagers, age ranging from 13 through 17. To do so, the researchers created a survey in the National Immunization Survey, with more than over 20,000 participants included in the survey. The main idea of the survey was to identify a method in which doctors could address why teenagers have not been vaccinated. By finding and understanding the underlying reason behind the lack of immunization, doctors and researchers alike can figure out how to tackle the idea that is holding back these teenagers from receiving treatment.

The second article evaluated in the debate was Vaccines and Autism: A Tale of Shifting Hypotheses written by Jeffrey Gerber and Paul A. Offit, and published in 2009 by the Children’s Hospital of Philadelphia. In this study, three main hypotheses were proposed in the discussion on how and why vaccines would cause autism in children. They were identified as: (1) the combination measles-mumps-rubella vaccine causes autism by damaging the intestinal lining, which allows entrance of encephalopathic proteins; (2) thimerosal, an ethylmercury-containing preservative in some vaccines, is toxic to the central nervous system; and (3) the simultaneous administration of multiple vaccines overwhelms or weakens the immune system. In this process, the researchers compared there hypotheses with preceding ecological studies conducted and observed in other countries such as the United Kingdom, Denmark, and Finland. A total of 20 different studies were analyzed in order to answer their proposed hypotheses.

The second article evaluated in the debate was Vaccines and Autism: A Tale of Shifting Hypotheses written by Jeffrey Gerber and Paul A. Offit, and published in 2009 by the Children’s Hospital of Philadelphia. In this study, three main hypotheses were proposed in the discussion on how and why vaccines would cause autism in children. They were identified as: (1) the combination measles-mumps-rubella vaccine causes autism by damaging the intestinal lining, which allows entrance of encephalopathic proteins; (2) thimerosal, an ethylmercury-containing preservative in some vaccines, is toxic to the central nervous system; and (3) the simultaneous administration of multiple vaccines overwhelms or weakens the immune system. In this process, the researchers compared there hypotheses with preceding ecological studies conducted and observed in other countries such as the United Kingdom, Denmark, and Finland. A total of 20 different studies were analyzed in order to answer their proposed hypotheses.

The first table shows the first 13 articles used to find an association between measles-mumps-rubella vaccine and autism.

The second table focuses on the last 7 articles used to find an association between thimerosal in vaccines and autism.

The next article in establishing disassociation between vaccines and autism is Vaccine Refusal, Mandatory Immunization, and the Risks of Vaccine-Preventable Diseases written by Saad B. Omer and Daniel A. Salmon, published in The New England Journal of Medicine in 2009. In this study, the researchers were concerned with the decline of immunization due to the lack of coverage and acceptance throughout country. They were highly motivated on the emphasis on how vaccination was necessary in preventing serious diseases and infections in today’s society. Similar to the first study used, the researchers used data from the National Immunization Survey from the years between 1995 and 2001. With this data, they compared the characteristics of children between the ages of 19 and 35 months who were unvaccinated, with those of characteristics who were partially vaccinated (undervaccinated). During this comparison, children who were medically exempt from receiving vaccines were exempt from the study. Secondly, a second part was conducted using the data from the NIS, in which a case controlled study on the knowledge, attitudes, and beliefs of parents of both vaccinated and unvaccinated children were compared to identify the reasons as to why the parents did not vaccinate their children.

The last study evaluated was Administration of thimerosal-containing vaccines to infant rhesus macaques does not result in autism-like behavior or neuropathology written by Bharathi S. Gadada, Wenhao Li, and others, published by the Proceedings of the National Academy of Sciences of the United States of America in 2015. The study, conducted at the University of Texas Medical Center, was centered around the idea of understanding whether the preservative used in vaccines, thimerosal, was the underlying reason for the development of autism in young children. To conduct this study, the team of scientists used a total of 79 male infant rhesus macaques, who were then split into 6 groups. In this experiment, the infant macaques receiving the vaccines were following the recommended vaccine schedules from the 1990s and 2008. These groups were composed of being (i) Control (n = 16), animals had received saline injections in place of vaccines; (ii) 1990s Pediatric (n = 12), animals received vaccines following the pediatric schedule recommended in the 1990s; (iii) 1990s Primate (n = 12), animals received vaccines recommended in the 1990s but on an accelerated schedule; (iv) TCV (n = 12), animals received all TCVs but no MMR vaccines following the accelerated schedule; (v) MMR (n = 15), animals only received the MMR vaccine but no TCVs following the accelerated schedule; and (vi) 2008 (n = 12), animals received vaccines recommended in 2008 but on an accelerated schedule. Infants were assigned to a peer group of four animals, with social behavior being evaluated on a daily basis. Changes in behavior such as withdrawal, aggression, and physical play were monitored, as well as the neurological stages of the three different brain regions,

The table above shows the amygdala that was studied in three groups of animals: Control, 1990s Primate, and 2008. The outline of the amygdala shows no change before and after the introduction of vaccines. The study on the primates followed the guidelines of the Animal Welfare Act and the Guide for Care and Use of Laboratory Animals of the National Research Council. All experimental protocols were approved by the University of Washington Institutional Animal Care and Use Committee.
responsible for behavior.

Results

After analyzing the research conducted by various sources, the evidence shows how vaccines do not cause nor are they a factor in the development of autism. Certain aspects were revealed, however, in the studies on why the records of immunizations are decreasing. In the studies using surveys and comparative studies, it was found that many children who are unvaccinated tend to belong to families who refuse vaccines. These parents believe that their children are not susceptible to the diseases, that the severity of the disease was low, and that the success rate of the vaccines are too low. The second largest group consisting of children who were partially vaccinated. This was because of the parents reporting that they did not receive a healthcare provider recommendation for their adolescent to receive the vaccine. Among those without a provider recommendation, the most common reasons for not receiving the vaccines were ‘vaccine not recommended’ and ‘not needed’. Among those with a recommendation, the most common parental reasons were ‘lack of knowledge’. Results also showed that immunizations were affected by geography, or location of the distribution. Exemption rates of vaccines tended to be higher in areas where parents did not vaccinate their kids (Saad B. Omer 4). The hypotheses proposed in the study done by researchers Jeffrey S. Gerber and Paul A. Offit were proven wrong by the 20 articles they had analyzed. Finally, the biological experiment of all 4 studies using the rhesus macaques show that there was no biological or social change in these primates after comparison of the controlled and experimental groups. In the chart displaying the region of the brain known as the amygdala, there was no change in shape or form of that area of the brain.

Conclusion

The idea that people across the United States find a revoked study from 1998 on vaccination and autism as true leads to the absence of necessary precautions that must be taken. The removal of vaccines in uneducated areas may lead to widespread disease that will affect both vaccinated and unvaccinated children. Due to this, diseases that were once eradicated may return and be more deadly to people who are unprotected. Hence the need for more funding on this issue and more education to those parents who have any concerns. Also, the persistence of doctors is crucial in answering any questions that the public may have as trust and knowledge shared between doctors and patients will lead to a more informed and safe.

 

References

Dorell, C. (2011, August 19). Parent-Reported Reasons for Nonreceipt of Recommended

Adolescent Vaccinations, National Immunization Survey. Retrieved October 28th, 2020, from http://journals.sagepub.com/doi/full/10.1177/0009922811415104

Gadad, B. S., & Li, W. (2015, August 9). Administration of thimerosal-containing vaccines to

infant rhesus macaques does not result in autism-like behavior or neuropathology. October 28th, 2020, from https://www.pnas.org/content/112/40/12498

Gerber, J. S., & Offit, P. A. (2009, February 15). Vaccines and Autism: A Tale of Shifting

Hypotheses. Retrieved October 28th, 2020, from https://academic.oup.com/cid/article/48/4/456/284219

Omer, S. B., & Simon, D. A. (2009, May 7). Vaccine Refusal, Mandatory Immunization, and the

Risks of Vaccine-Preventable Diseases | NEJM. Retrieved October 28th, 2020, from http://www.nejm.org/doi/full/10.1056/NEJMsa0806477