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Absolutely Outstanding! Your paper is one of the best I have read! May I use it as an example in the future? A million gold stars for you! VACCINES: FIRST DO NO HARM by Lori Patrick ENG 102 Section 1460 November 21, 2007 Explanatory Report /MLA Format Abstract This report focuses on the debate concerning thimerosal, an additive used in vaccines, and the link to an increase in the number of cases of autism and possibly other neurodevelopmental disorders. Developed in the late 1700s in response to the smallpox epidemics of that time, the vaccine has been proven to be a solid foundation on which Americans put their health and trust. However, this trust may have been misplaced for many unfortunate parents and children. The effects of large doses of thimerosal that are received during multiple vaccines during the first year of life are thought to be the cause of autism. There has been no proof for or against this theory. Vaccines: First Do No Harm Thesis: The vaccine has been one of the best medical breakthroughs in the advancement of public health but is now being viewed as a threat to the health of those it is meant to help protect. I. II. III. IV. The vaccine is used in the prevention and eradication of many diseases. A. Definition of the vaccine B. History of the vaccine 1. Who developed and when 2. Diseases/illnesses developed for C. Ingredients used in the vaccine 1. Thimerosal a. Ethyl mercury b. Methylmercury 2. Aluminum In many cases, thimerosal is thought to be the cause of autism and other disorders. A. Autism 1. Definition of disorder 2. Symptoms of disorder 3. Causes of disorder B. Other disorders The levels of mercury received during a vaccine can cause mercury poisoning. A. Levels considered toxic B. Levels in vaccines 1. Multiple vaccines at same time 2. Last dose in vial C. Mercury toxicity D. Changes in vaccine schedule There has been no conclusive proof for or against the thimerosal-autism theory. A. Statistics in California 1. Changes in cases of autism 2. Changes in vaccination schedule B. Removal of thimerosal from vaccines C. Autism in China and other countries Nearly everyone born in the United States has received vaccines. Proof of vaccinations is required to gain admittance to daycares, public schools and the military; some employers and volunteer agencies even require proof of vaccinations. Many parents take their children to the doctor as part of the well-child visit to receive vaccines because it is a part of the routine care that children receive and which plays an important role in their health. Why are vaccines so important and what is their purpose? What if these very vaccines have the potential to cause illnesses that will impact both the lives of the parents and of their children forever? The vaccine has been one of the best medical breakthroughs in the advancement of public health but is now being viewed as a threat to the health of those it is meant to help protect. The best definition of a vaccine is put forth by Allen as “a substance that introduces a whole or partial version of a pathogenic microorganism into the body in order to train the immune system to defend itself when the organism threatens to cause in infection through natural means” (14). In our country today, many of the diseases for which vaccines were produced are no longer a threat to children or adults. Currently vaccines can prevent anthrax, cervical cancer, diphtheria, hepatitis A & B, Haemophilus influenzae type b, HPV, influenza, Japanese encephalitis, Lyme disease, measles, meningitis, monkeypox, mumps, pertussis, pneumonia, polio, rabies, rotavirus, rubella, shingles, smallpox, tetanus, tuberculosis, typhoid fever, chickenpox and yellow fever. The continuation of the majority of these vaccines will ensure that these diseases remain a thing of the past. There are some vaccines that are given as a prophylaxis against illnesses but are not required for every person and are given only if there is an immediate threat in continued health without the benefit of receiving these vaccines, such as influenza and pneumonia, which does not ensure that these diseases will not return. For those diseases that are the most serious, it is very important for children to be vaccinated starting from birth. However, the amount of vaccines that are required at one time are numerous (See Figure 1 below). By the time a child is six years of age, he or she will have potentially received a total of 34 vaccines which include a yearly flu vaccine. Figure 1: Recommended Immunization Schedule (CDC). The modern day vaccine was developed by a doctor named Edward Jenner from England during the smallpox epidemics of the 1700s. However, the very first vaccines were given in May of 1796, using a syringe made from the end of a quill and a small surgical knife. Dr. Jenner took the discharge from the sores of a girl infected with cowpox and rubbed it into two open wounds on the arm of a boy, who started displaying the symptoms of the disease. Dr. Jenner then stuck the boy with the actual smallpox virus and found that the boy did not develop any symptoms, concluding that the cowpox prevented the boy from developing smallpox (Allen). The smallpox vaccination is no longer given to the general public because of the eradication of this particular disease around the whole world. However, with the War on Terrorism that started in full force in 2001, nearly all soldiers serving in the military were given this vaccine. Many vaccines are packaged in vials that contain enough of the vaccine for multiple shots. Once a needle punctures the vial, it can become contaminated with bacteria, requiring the use of a preservative, thimerosal, to help in keeping the contents sterile (Kirby). Manufacturers have been adding thimerosal, which is a form of mercury, to vaccines since the 1930s (Jenson). There are many other ingredients used in the production of vaccines, among them aluminum (Kirby). Both mercury and aluminum are considered to be neurotoxins which “act[s] specifically on nervous tissue” (Stedman). There are three types of mercury that are organic, with the two most common being methylmercury and ethylmercury. Methylmercury is a form of mercury that is usually found in certain types of fish such as swordfish and other predatory fish. A person who includes these types of fish regularly in their diet may have a high exposure to mercury. Certainly, a pregnant woman can pass this type of mercury to her fetus. Ethylmercury is the type of mercury found in thimerosal and differs from methylmercury in that it stays in the blood longer, resulting in a buildup of the mercury. In addition is the fact that “organic compounds are a more dangerous form of mercury, which is considered to be the second most toxic substance on earth, after plutonium. Mercury is a recognized neurotoxin that can destroy cells in key centers of the brain and nervous system. It is especially hazardous to fetuses and small infants, whose vital organs are still developing” (Kirby). It is easy to see why thimerosal exposure has been thought to be the cause of several neurodevelopmental disorders including autism. Of the many other ingredients used in vaccines, one other disturbing element is aluminum, which is used in order to aid in the body’s healthy reaction to the virus in the vaccine. Interestingly, when “mercury and lead are combined, the compound becomes much more lethal than either metal alone” (Kirby). These factors would increase the likelihood of someone receiving a vaccine with the potential to be neurotoxic, even increasing the risk of developing a neurodevelopmental disorder. Recently, there has been a rise in the awareness of the alarming increase in autism, which is thought to be linked to thimerosal in vaccines. Autism is a neurodevelopmental disorder that is “characterized by ‘severe and pervasive impairment in several areas of development’” (Autism). It impairs a person’s brain function, speech and communication, and interaction with other individuals. As with many such diseases, the severity differs as well as the way in which it impacts each person. There is no specific medical test that is used in the diagnosis of autism. Instead, behaviors are evaluated in conjunction with medical testing to rule out other causes. The sudden loss of language and/or social behaviors is the most alarming of the symptoms in the onset of this disease (Autism). The Autism Society has stated that “there is no known single cause for autism, but it is generally accepted that it is caused by abnormalities in brain structure or function.” There are cases that are congenital and those that are caused by medical problems (Autism). Of those that are not born with the disorder, the others that develop autism do so between one and three years of age with normal development and then a decline in skills. This last category is what is thought to be caused by thimerosal. While thimerosal alone cannot possibly be the solitary cause of autism, it is thought that these cases are the result of a combination of a “genetic predisposition” and the exposure to thimerosal (Kirby). It is of note that sometime in the early 1940s the first case of autism was reported, which would have been just a few years after thimerosal was used in vaccines. Other neurodevelopmental disorders thought to be associated with thimerosal are attention deficit disorders, speech/language disorders, sleep disorders and tics (Kirby). The levels of mercury received during a series of vaccinations can cause mercury poisoning. Different government agencies have issued safety levels for what they consider to be the safe maximum daily exposure to ethylmercury. The Environmental Protection Agency determined that 0.5 micrograms per kilogram of weight is considered safe, whereas the Agency for Toxic Substances and Disease Registry considers 1.5 micrograms per day to be safe, and the FDA considers 2.0 micrograms per day to be safe. There are differing amounts of ethylmercury in each vaccine, with the diphtheria-tetanus shot containing 25 micrograms, the Hib shot 25 micrograms, and the hepatitis-B 12.5 micrograms. When given in a series of shots at one time, these can add up to as much 125 times the amount of what is considered safe in a single day. Additionally, a high dose of mercury exposure at one time is more damaging than a low dose given daily (Kirby). Also of concern is the last vaccine in a multi-dose vial. The total ethylmercury added to this vial, being a metal, would settle to the bottom of the vial. While the manufacturers warn to shake vigorously before each use, that may not happen each time the vial is accessed, making the last dose the most lethal (Kirby). For instance, if the Hib shot came in a ten-dose vial and each dose contained 25 micrograms of ethylmercury, the entire vial would then contain 250 micrograms. Therein lies many different variables in being able to calculate the potential exposure in that last vaccine. For instance, if the last dose in the vial contained half of the mercury in the vial, that dose would exceed the EPA limit by almost 250 times. All of these variables together would then impact each child differently in what type of exposure they received. Mercury exposure can have a wide range of side effects depending on the particular type of mercury, but these effects depend on the amount and length of exposure. Other factors include the age at which exposure occurred and the health of the person that was exposed (Risher). In addition, “individual sensitivity seemed to arise from predetermined genetic factors” (Kirby). Studies have shown that methylmercury exposure that is persistent and in low levels produces decreased ability in muscle movements that affect leg movement, deep-tendon reflexes as well as language problems (Ronchetti, et al). A physician from Baton Rouge, Dr. Stephanie Cave, has treated numerous children with autism and believes that ethylmercury “enters the brain and is converted to inorganic mercury, which cannot cross back over the blood-brain barrier” (Kirby). To date, there has been no definite proof either for or against the theory that thimerosal causes autism, but there is what could be called overwhelming circumstantial evidence for the theory. The figure below (See Figure 2) demonstrates the correlation between the rise in exposure to mercury through vaccines and the rise in autism. As of 1996 in California alone, these figures translate to one in five hundred children with autism as compared to one in two thousand children in 1985. That means that the reported cases have quadrupled in just over eleven years. Of note is the time period when cases of autism really began to increase, from 1990-1992. One possible explanation for this alarming increase is the addition of more vaccines to the schedule during that time. The Hib vaccine, which requires five doses, and the hepatitis-B vaccine, which requires three doses with the first given as soon after birth as possible were both added to the schedule during this time, which increased the mercury levels. Figure 2: Rising Levels of Cumulative Mercury Exposure from Childhood Vaccines, Compared with Rising Incidence of Autism in California (Kirby). Of the autistic children that she treats in her clinic, Dr. Cave states that “mercury had caused the autistic symptoms, because the vaccines corresponded to ‘critical periods of neuronal development’ in infants, when the blood-brain barrier is not fully developed and bile production is minimal, ‘making it more difficult for metals to be cleared from the body’” (Kirby). Sometime during 1999, the FDA started to implement a gradual removal of thimerosal from vaccines. It was during this time that President Clinton decided to send hepatitis-B vaccines that contained thimerosal to impoverished countries, which were contained in multi-dose vials. It seems as though autism has not been reported very often in some other countries such as China. Two pharmaceutical companies decided to start marketing and selling certain vaccinations such as the hepatitis-B, DTP, Hib and MMR to certain governments including China. In August of 2004, China reported that there had been an increase in the number of cases of children with autism over a period of a few years. These numbers were alarming due to the fact that there had previously been very few cases of autism reported. Suddenly, there were approximately 1.8 million children with autism. There has been a rise in the number of cases of children with autism in other countries including Indonesia, Argentina, India and Nigeria (Kirby). The vaccine will continue to be an extremely important tool in healthcare due to the likelihood of more diseases that will undoubtedly occur throughout time and also because of the new War on Terrorism. Mercury has been slowly removed from some vaccines but has not been totally removed from all of them. Since there has been no definite proof of the thimerosal-autism theory, the removal of this element from vaccines will hopefully cause a decline in the number of cases of autism. Only time will prove or disprove this theory, but then again, there may be other factors involved that have not been considered. The chance for contamination of future vaccines through other means is certainly possible, as well as new developments in producing vaccines in a safer environment to be contaminated as well. It is frightening to think that one of the most important fundamental tools that helps contribute to healthy children and adults is the very thing that may cause immeasurable harm. Works Cited Allen, Arthur. Vaccine: The Controversial Story of Medicine’s Greatest Lifesaver. New York: W. W. Norton & Company, 2007. Allen traces the vaccine’s history over the last 300 years from its discovery through the current-day controversy over its safety and the future outlook. Autism Society of America. Understanding Autism. 15 Oct 2007 <http://www.autism-society.org>. This web site contains information for those seeking answers to questions about autism. Not only does it explain the disease, symptoms, possible causes and diagnostics, but also provides links to resources, local chapters for support as well as how to get involved in supporting advancements. Center for Disease Control and Prevention. Vaccines & Immunizations. 29 Oct 2007 <http://www.cdc.gov/vaccines>. A very informative web site that provides information on just about anything someone might want to know about vaccines. There are links to other information data bases and plenty of articles. Jenson, Hal B. “How Harmful Are Additives in Childhood Vaccines?” Postgraduate Medicine. May 2002 111.5:87. EBSCO Host. Glendale Community College Library Media Center, Glendale, AZ. 15 Oct 2007. Jenson answers this question with information about the substances added to the vaccine, the role they play and their effects as well as noting that agencies have not found any evidence that thimerosal causes harm. Kirby, David. Evidence of Harm: Mercury in Vaccines and the Autism Epidemic: A Medical Controversy. New York: St. Martin’s Press, 2005. Kirby investigates the thimerosal-autism theory that is surrounding the vaccine. He tells the story of several different families who were suddenly faced with the diagnosis of autism in their children and their fight to uncover the truth and force the government to do something to help children in the future and make the vaccine safe. Risher, John F., and Christopher T. DeRosa. “Inorganic: The Other Mercury.” Journal of Environmental Health. Nov 2007 70.4:9-16. EBSCO Host. Glendale Community College Library Media Center, Glendale, AZ. 18 Oct 2007. In this article, the authors look at mercury, the sources of exposure, health effects of exposure and medical uses of mercury. Ronchetti, Roberto, et al. “Children’s Health and Mercury Exposure.” Acta Paediatrica. Oct 2006 95:36-44. EBSCO Host. Glendale Community College Library Media Center, Glendale, AZ. 29 Oct 2007. This is an informative article regarding sources of mercury with emphasis on organic mercury, particularly methylmercury. Discussed are the health consequences of exposure in children. Stedman’s Medical Dictionary for the Health Professions and Nursing: Fifth Edition. Baltimore: Lippincott Williams & Wilkins, 2005. This dictionary contains definitions to over 51,000 words used in medicine as well as 900 illustrations.