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Pediatric vaccine preservatives


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Novel paper researched 3 vaccine preservatives: Aluminum, Ethyl Mercury, and Formaldehyde to assess if concerns regarding their presence in vaccines was valid in certain patient populations. Vaccine ingredient tables and graphics were included and determination that certain populations were at risk for negative health effects. Recommendations were made.

Published in: Health & Medicine
  • The scholarly articles and the lectures by MIT research scientists reviewed report the use of Aluminum in vaccines as being harmful regardless of whether it’s an adjuvant or a preservative. It is reported by the CDC as a replacement for Thimerosal as a vaccine preservative. Bottom line: whether you believe a small amount is harmful or not, you cannot argue that all vaccine ingredients are perfectly safe. A very large number of persons who have experienced life altering events after receiving vaccines did not infact experience vaccine safety. We should be looking at ALL ingredients in vaccines (whether you deem them safe for the majority of people) and studying them to evaluate risk—this means special populations. I appreciate your opinion and my aim is to determine, what groups of individuals may be at risk and would not be candidates for certain vaccines. I merely reported what the literature search revealed. Nothing more.
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  • Aluminum is used as an adjuvant in vaccines, not a preservative - something that they mistakenly said in this paper. I find it interesting that they also only pointed out studies done with IV infusion or oral dosing of aluminum and said nothing about concentration (something commonly done by many anti-vaxxers) in this study. The very small amount of aluminum used in vaccines is delivered IM and thus, both because of small concentration and delivery method pose no risk to these children. I should also point out that scientists are actively looking at other adjuvants that would be useful in vaccines, because the more pure we can make them and the more we can minimize other chemicals or irritants in vaccines, the better. The same goes for formaldehyde! While yes formaldehyde can be toxic in large doses, this is not the case in vaccines. As well, everyone should be aware that formaldehyde is actually produced in the body at larger doses than one would ever get from a vaccine. Finally, while the fact that thimerosal has been removed from pediatric vaccines for a decade now, but we still see a rise of ASD and the other diseases that people were concerned about, tells us that thimerosal was not the culprit. On this end, I think many scientists are happy to see thimerosal removed however. Even though ethylmercury is much less of a risk than methyl mercury, I never was comfortable with seeing any amount of mercury in vaccines - even if it is much less than I get in my tuna every time I go out for sushi! Bottom line, I appreciate the concern in this article, but I think that the paper is poorly written and leads one to conclusions that are inaccurate and not backed by research. I really like a lot of the other papers you have posted though. Thank you for those!
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Pediatric vaccine preservatives

  1. 1. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives Pediatric Vaccine Preservatives Aluminum, Thimerosal, and Formaldehyde By Kimmer Collison-Ris MSN, FNP-BC, WOCN, MS CAM ACHS Chem 501 Fall 2015
  2. 2. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 1 Abstract Vaccines are used to decrease disease in humans and have been used for the past 100 years. Since the 1960’s a number of vaccines have been added to the vaccine schedule with the required pediatric doses nearly tripling since 1983 (Graphic 1 at left). Today the diseases vaccines address are less prevalent in developed nations due to modern health and hygiene practices along with aggressive vaccination programs (CDC, 2015). Pediatric autoimmune and neurodevelopmental disorders have significantly increased in the last few decades (Velasques-Manoff, 2012). Because our current vaccines contain several different preservatives which have a recognized negative health impact; health providers, researchers and parents are questioning the risk verses benefit to pediatric patients. A literature Search was performed utilizing the search engine Google Scholar and Google for information on the current vaccine schedule and each vaccine’s ingredients. Three main preservatives were chosen as the topic of interest: Aluminum, Thimerosal (Ethylmercury), and Formaldehyde. Did a reasonable concern exist regarding specific vaccine preservatives and safety in some populations? Could Aluminum, Thimersal (Ethylmercury), and Formaldehyde used as preservatives in small doses in vaccines be more harmful than beneficial to special populations? This paper seeks to analyze three preservative ingredients and their impact on health to evaluate if cautions should be considered for the current vaccine schedule in specific vulnerable populations.
  3. 3. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 2 Pediatric Vaccine Preservatives: Aluminum, Thimerosal, and Formaldehyde Introduction Vaccines are used to decrease disease in humans and have been used for the past 100 years. Since the 1960’s a number of vaccines have been added to the vaccine schedule with the required pediatric doses nearly tripling since 1983 (Graphic at left). Pediatric autoimmune and neurodevelopmental disorders have significantly increased in the last few decades (Velasques-Manoff, 2012). Because our current vaccines contain several preservatives which have a recognized negative health impact; health providers, researchers and parents are questioning the risk verses benefit to pediatric patients. There has been great controversy and concern over the safety and efficacy of the current vaccine schedule given the myriad of ingredients contained in the vaccines on the developing neurological system and the necessity regarding the types and numbers of required pediatric vaccines. Today the diseases vaccines address are less prevalent in developed nations due to modern health and hygiene practices along with aggressive vaccination programs (CDC, 2015). Many vaccine proponents believe the current vaccine schedule is necessary for continued disease control. Opponents question their safety and efficacy as preservatives used in vaccines may be to blame for the increase in pediatric neurodevelopmental disorders, immune dysfunction, and some cases of pediatric mortality. Could the rising incidence of neurodevelopmental disorders be related to a cumulative effect of increased vaccine preservatives, genetic vulnerability and immune dysfunction? Could Aluminum, Thimersal (Ethylmercury), and Formaldehyde used as preservatives in small doses in vaccines be more harmful than beneficial to special populations?
  4. 4. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 3 This paper seeks to analyze three preservative ingredients and their impact on health to evaluate if cautions should be considered for the current vaccine schedule in specific populations. Research Methodology A literature Search was performed utilizing the search engine Google Scholar and Google for information on the current vaccine schedule and each vaccine’s ingredients. Three main preservatives were chosen as the topic of interest: Aluminum, Thimerosal (Ethylmercury), and Formaldehyde. Research Parameters involved searching abstracts and articles by scientists and healthcare providers from 1985 to the present on vaccine ingredients, vaccine preservatives, Aluminum and health, Aluminum and development, Aluminum and human toxicity, Ethylmercury and vaccines, Ethylmercury and health, Ethylmercury and toxicity, Ethylmercury and Methyl Mercury, Formaldehyde and vaccines, Formaldehyde and human health, Formaldehyde absorption, Formaldehyde health effects, and Formaldehyde and development. Additionally, searches for descriptions of vulnerable populations and relationship to Aluminum, Ethylmercury, and Formaldehyde were also performed. History of Vaccination Immunization began when it was discovered that a milkmaid who contracted cowpox did not then develop smallpox when later exposed. From this observation, Edward Jenners created the world's first vaccine for smallpox in the 1790s. The Pertussis vaccine was licensed in 1949, Polio in 1955, Mumps in 1967, Measles in 1963, and Hepatitis A received licensing in 1995 and Hepatitis B in 1991. These diseases have reportedly been on the decline in developed nations believed to be due to increased nutrition, sanitation, health and hygiene practices prior to the aforementioned vaccine requirements (McKinlay, McKinlay, and Milbank; 1977). However, the WHO (2014) and the CDC (2014) report that the decline in the infectious diseases named is
  5. 5. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 4 related to their aggressive vaccination and booster programs worldwide. Pertussis has experienced a resurgence among the vaccinated (Mughal, Kazi, Bukhari, Ali, 2012). Purpose of Vaccines Prior to birth, a baby receives antibodies from the mother. These maternal antibodies provide protection against many of the previously “usual childhood infections” such as measles, mumps and chickenpox, and bacteria such as H. influenzae and Streptococcus pneumoniae. For a few weeks after birth, babies have some protection from germs that cause diseases; this protection is passed from their mother through the placenta before birth. The levels of these antibodies decrease so that by 6 months, protection is minimal. “The decision as to when to give a vaccine is based on the epidemiology of the vaccine preventable disease. Often, these diseases are more severe in younger children. Therefore, we start early to ensure that the youngest and often most fragile are protected as soon as possible” (NIH, 2015). The vaccine schedule ensures that while the levels of maternal antibody are falling, infants are developing their own antibodies due to immunizations. The goal is to protect the infant as soon as possible. Although the incidence of most vaccine-preventable diseases in the United States is very low, the CDC claims this is because the majority of U.S. children are immunized (Fisher and Bocchini 2009). Vaccine Ingredients Vaccines contain antigens, which cause the body to develop immunity. Additionally, they contain adjunctive ingredients which assist in producing the vaccine, or in prolonging shelf life and protection from viral and/or bacterial contamination (CDC, 2014). Chemicals used in the production of vaccines include suspending fluid (sterile water, saline, or fluids containing protein);
  6. 6. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 5 preservatives and stabilizers (albumin, phenols, and glycine); adjuvants or enhancers that enhance the vaccine's effectiveness, and culture material used to grow the virus or bacteria ( Key preservatives used in vaccines include Aluminum, Ethyl Mercury (Thimerosal), and Formaldehyde. The graphic lists common vaccine ingredients and their function ( For a detailed list of current vaccines and their specific ingredients see (Table 3) at the end of this paper. Key Vaccine Preservatives Aluminum Aluminum (Al) is a trivalent cation found in its ionic form in most kinds of animal and plant tissues and in natural waters everywhere. It is the third most prevalent element and the most abundant metal in the earth's crust, representing approximately 8% of total mineral components. Due to its reactivity, Al in nature is found only in combination with other elements (Bernardo, 2014). There is no known physiological role for aluminum within the body and hence this metal may produce adverse physiological effects (Nayak 2002). Al is used in vaccines as a preservative in the form of a gel or salt and added to the vaccine to enhance the vaccine by promoting an earlier, more potent response, and more persistent immune response to the vaccine (CDC, 2014). Al impact upon animal and human health Al is absorbed from the GI tract in the form of oral phosphate-binding agents (aluminum hydroxide), parenterally via immunizations, in dialysate, total parenteral nutrition contamination, via bladder irrigation, and transdermally (antiperspirants). Lactate, citrate, and ascorbate all facilitate GI absorption. If a significant Al load exceeds the body's excretory capacity, excess is deposited in various tissues (bone, brain, liver, heart, spleen, and muscle). This accumulation
  7. 7. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 6 causes morbidity and mortality through various mechanisms (Bernardo, 2014). In healthy subjects, only 0.3% of oral Al is absorbed via the GI tract and the kidneys effectively eliminate Al from the human body. When the GI barrier is bypassed, as in IV infusion or advanced renal disease, does Al accumulate. For example, 40% of IV infused Al is retained in adults but up to 75% is retained in neonates (Yokel, 2000). Decreased renal function increases human risk of Al-induced accumulation and toxicity. Brain Al entry from blood may involve transferrin-receptor mediated endocytosis and a more rapid process transporting small molecular weight Al species. Al efflux appears from the brain, possibly as Al citrate. Potential for accumulation of Al exists from repeated exposure, as there is prolonged retention of Al fraction that enters the brain. Al is a neurotoxicant in animals and humans exhibiting similar effects on the brain as mercury. This neurotoxicity, produced by several mechanisms, (Xu, Farkas, Kortbeek, Zhang, Chen, Zamponi, and Syed (2012) damages the immune system and may be key in increased pediatric autoimmune diseases. Mitochondrial disorder is suspected in association with severe vaccine-injury, including autism as Al toxicity targets the mitochondria (Piper-Terry, 2012). Al is now implicated in the etiology of sporadic Alzheimer's disease (AD) and other neurodegenerative disorders (Yokel, 2000; Mercola 2010). Excess, insoluble amyloid beta protein (A beta) contributes to AD; promoting formation and accumulation of insoluble A beta and hyperphosphorylated tau. Al mimics cortical cholinergic neuro-transmission deficit as seen in AD; Al increases Fe-induced oxidative injury. Al toxicity affects plants, aquatic life and humans; likely by common mechanisms: disruption of the inositol phosphate system and Ca regulation. Fe-induced oxidative injury facilitation and disruption of basic cell processes may mediate primary molecular mechanisms of Al-induced neurotoxicity (Yokel, 2000). Largely
  8. 8. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 7 95% of an Al load becomes bound to transferrin and albumin intravascularly; later renally excreted (Barnardo, 2014). Animal studies using rats, mice, and rabbits; found that Al is distributed transplacentally and is present in milk. Oral Al ingestion during pregnancy produces a syndrome including growth retardation, delayed ossification, and malformations at doses that also cause reduced maternal weight gain. The severity of the effects is dependent on the form of Al given. Postnatally, reduced pup weight gain and neuromotor development effects are a result of developmental exposures (Golub and Domingo, 1996). Al Injections to animals produce behavioral, neuropathological and neurochemical changes that partially model AD (Yokel, 2000). When Al Toxicity occurs the action potential is blocked, decreasing neuron transmission within the brain. Enzymes as catalysts are inhibited. This neurotransmitter inhibition of Dopamine, Norepinephrine and Serotonin (5-HTP) directly impacts attention, impulse control, mood regulation, sleep/wake cycles, hunger/satiety, voluntary/involuntary movement, and fight- or-flight responses; thus leading to ineffective sensory processing of auditory/visual stimuli; auditory processing disorder, visual processing disorder, and sensory integration dysfunction (Piper-Terry, 2012). In all cases, Aluminum toxicity is largely related to Al bioavailability, which then depends upon Al coordination chemistry in vivo. The highly polarizing power of the Al3+ ion dictates its particular affinity for oxygen donors that abound in essential biomolecules and dietary substances. The influence of these substances on Al bioavailability, metabolism and toxicity can be assessed through animal models. However, understanding the mechanisms through which Al–ligand interactions may influence physiological processes on the molecular level requires knowledge of the speciation of the metal in the main biofluids (Berthon, 2002).
  9. 9. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 8 Formaldehyde Formaldehyde is an odorless, highly toxic, slightly heavier than air, volatile organic compound, that easily becomes a vapor or flammable gas at room temperature. It has a pungent, highly irritating, suffocating odor; detectable at low concentrations, but may not provide adequate warning of hazardous concentrations for sensitized persons (ATSDR, 2015). It is also naturally produced in small, harmless amounts in the human body. The chemical symbol for formaldehyde is CH2O (Geier and Geier, 2004). Synonyms include formalin, formic aldehyde, methanal, methyl aldehyde, methylene oxide, oxomethane, and paraform (ATSDR, 2015). Formaldehyde is used in vaccines in an aqueous solution stabilized with methanol and used as a preservative to inactive bacterial toxin products for toxoid vaccines, to produce immunity, and to kill viruses during the manufacturing and storage process. A large percentage of formaldehyde is removed from the vaccine before packaging (CDC, 2015). Impact on human/animal health Formaldehyde is highly toxic to all animals, regardless of method of intake (ATSDR, 2015; ChemSee, 2015) being absorbed well by the lungs, gastrointestinal tract, and, to a lesser extent, skin. Systemic effects include metabolic acidosis, CNS depression and coma, respiratory distress, and renal failure. Formaldehyde reacts with strong oxidizers, alkalis, acids, phenols, and urea. Children may be more susceptible than adults to the respiratory effects. It interacts with proteins and DNA on cell membranes in body tissues and fluids; disrupting cellular functions. High concentrations cause precipitation of proteins, which results in cell death. It is a potent sensitizer and known human carcinogen and listed as a human carcinogen in the Thirteenth Report on Carcinogens published by the National Toxicology Program as it causes cancer of the throat, nose, and blood (ATSDR, 2015).
  10. 10. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 9 Studies on the interactions between formaldehyde and proteins at the molecular level, affect the body’s carrier protein, serum albumin. This binding loosens the skeletal structure of albumin and exposure of the aromatic ring amino acids in the internal hydrophobic region (Wikepedia, 2015). Exposure affects personal awareness, causing fatigue and if prolonged, can cause severe allergic reactions of the eyes, skin (rashes), and asthma-like symptoms (coughing, wheezing, chest tightness), menstrual disorders, and subnormal body temperature. Asthmatics appear more sensitive to formaldehyde (Geier and Geier, 2004; NIH, 2015). Thimersol (Ethylmercury) Mercury exists in several chemical forms; each with specific effects on human health: Methylmercury, Ethylmercury, Elemental mercury, inorganic and organic mercury compounds (, 2014; WHO, 2014). It is a highly toxic element second only to radioactive plutonium, when combined with other ingredients, specifically aluminum and formaldehyde, as the synergistic effects increase 10,000-fold (Laibow, 2015). Thimerosal (Ethylmercury), an organic compound, is 49.6% mercury by weight and is metabolized or degraded into Ethylmercury and thiosalicylate. Ethylmercury is a cation composed of an ethyl group bound to a mercury(II) center; its chemical formula is C2H5Hg+. Known as, C9H9HgNaO2S, it is formed from combining of ethyl mercuric chloride, thiosalicylic acid, sodium hydroxide, and ethanol. Currently, there are no existing guidelines for Ethylmercury, the metabolite of Thimerosal (, 1999). Thimerosal (sodium ethylmercurithiosalicylate), a preservative, used in some United States vaccines, was first introduced by Eli Lilly Company in the 1930's (CDC, 2014). It was added to vaccine vials containing more than one dose to prevent contamination and growth of harmful bacteria. However, it was removed from U.S.A. childhood vaccines (2001) and single-dose flu vaccines;
  11. 11. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 10 except for the multi-dose inactivated flu vaccine vial (CDC, 2015). Impact on human/animal health Thimerosal has been studied in animal models only. Blair and colleagues (1975) studied Thiomersal administered to adult squirrel monkeys who received a dose equivalent of 1 or 6 μg/kg/day Ethylmercury. Researchers noted Ethylmercury significantly converted to inorganic mercury; with the highest levels were found in the kidney but low levels were present in the brain. Adult male and female rats in another study were administered 5 daily doses of equimolar concentrations of ethyl or methylmercury by gavage and tissue distribution, neurotoxicity and nephrotoxicity assessed (Magos, Brown, Sparrow, Bailey, Snowden, Skipp; 1985). Researchers found neurotoxicities of methyl and ethyl mercury were similar in the subjects. In this study, higher levels of inorganic mercury were seen in the brains of the Ethylmercury treated rats and renal damage was greater in Ethylmercury treated rats. Researchers concluded neither time- course nor dose response attempted; they found the biological half-life in adults of ethyl mercury 30 - 50 days. Other studies report Ethylmercury clears from blood with a half-life of about 18 days in adults and is eliminated from the brain in about 14 days in infant monkeys. Comparative Critical Toxicology Studies on Thiomersal related Ethyl mercury and methylmercury have been performed. Both studied developmental neurotoxicity, assessing dose response and age dependent responses. Mechanistic studies focused on critical changes in gene function and cellular pathways. Evaluation of possible sensitive subpopulations based on genetic predisposition, diet, and cumulative risk. Biomarkers of exposure including hair need to be evaluated. “Ethylmercury is probably slightly less toxic than methylmercury. However, the database for Ethylmercury is weak which creates considerable uncertainty in risk assessment comparisons (Barrett, 2005). Ethylmercury should be considered equipotent to methylmercury as
  12. 12. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 11 a developmental neurotoxin. This conclusion is clearly public health protective. Ethylmercury exposure from vaccines (added to dietary exposures to methylmercury) probably caused neurotoxic responses (likely subtle) in some children (IOM, 2015;). Clinical manifestations of Ethylmercury poisoning include speech and vision disorders, tremor, Ataxia, spasticity, delirium, and death. Fetuses exposed to forms of mercury in utero are the most severely affected; symptoms include low birth weight, seizure disorders, profound developmental delay, incomplete visual loss or total blindness, and hearing loss (Olson, 2014). Neuronal atrophy is diffuse and widespread, found in severe in cases exposed in utero. Long- term studies may indicate that even prenatal exposure at low concentrations can cause subtle, but detectable, decrements in the areas of motor function, language, and memory. Affected children may have long-term stigmata, including motor impairment, visual loss, hearing loss, developmental delay, and seizure disorders (Olson, 2014). The severity of health effects regarding Ethylmercury exposure include: the chemical form of mercury, the dose, individual’s age at exposure (fetus most susceptible), duration of exposure, route of exposure, and health at time of exposure (IOM, 2015). Blood levels of Ethylmercury greater than 500 ppb can produce these adverse effects. Subtle measures of developmental neurotoxicity (as done for Methylmercury) have not been evaluated. The Institute of Medicine (IOM) emphasize infants are more susceptible than adults (IOM, 2015). Individuals who suffer from chronic mercury exposure will have a unique expression of symptoms (Laibow, 2015). Although Ethylmercury is approximately 5 times less acutely toxic than methylmercury, Ethylmercury is a neurotoxin (IOM, 2015). Data is not adequate to compare potencies of Ethylmercury and methylmercury for developmental neurotoxicity. The mechanisms responsible for organomercurial caused developmental neurotoxicity are unknown and this also complicates
  13. 13. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 12 evaluation of structure/ activity relationships. While the toxicity of low‐levels of Ethylmercury is still under debate, the American Academy of Pediatrics, along with the American Academy of Family Physicians, the Advisory Committee of Immunization Practices, and the US Public Health Service issued a joint recommendation that Thimerosal be removed from vaccines as quickly as possible as a precautionary measure (, 2015). Vulnerable Populations There are a variety of definitions for vulnerable populations. The World Health Organization (WHO) defines vulnerable populations as infants under 6 months, the elderly, breastfeeding or pregnant women, and persons with underlying medical conditions (WHO, 2015b). Vulnerable populations in this paper includes low birth weight or preterm infants, babies <6 months, nursing or pregnant women, young children; individuals with chronic heart, lung, metabolic, renal or liver disease; chronic neurological conditions, or immunodeficiencies, children aged 6 months to 5 years, and residents in long term care facilities. Seneff, Davidson, and Liu (2012) reported that persons on the Autism spectrum were particularly vulnerable to Aluminum and Mercury. The Mount Sinai Hospital website lists their group of vulnerable populations to Mercury exposure as infants and young children (2015). Adverse Vaccine Reactions (VAERS) The CDC recommends giving vaccinations to healthy persons; but often all infants, very young children, low birth weight, poor renal function, and immunocompromised persons are given vaccines regardless. The CDC states on the VAER website, “as with all medical products, no vaccine is perfectly safe or effective. Vaccines can cause minor adverse effects such as fever or local reactions at the injection site. Rarely, they can cause serious adverse effects such as febrile seizures or severe allergic reactions. Adverse events (AE) can also occur coincidentally
  14. 14. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 13 after vaccines…”(2015). A person can experience any of the symptoms listed in the hours, days or weeks following vaccination which should be reported to VAERS. Discussion Safety and efficacy in specific populations Children are especially sensitive to chemical exposure, particularly because their livers may not be as effective at ridding the body of toxins, they have a high rate of cell growth and division, which makes the cells more susceptible to damage. Damage to cells at an early age can lead to defects that persist throughout their lifetimes. We do not even have sufficient testing methods to evaluate the effect of chemical exposure on learning and cognitive ability. The dramatic increase in Autism and Attention Deficit Hypersensitivity Disorder (ADHD) may be linked to chemicals in the environment (IOM, 2015). "Given the large number of new chemicals introduced into the environment each year, and the lack of information about their effect on human function and health, particularly their potential effect on children, there is a growing need to measure the exposures of children to these agents more systematically and to understand better their potential effect on children's development. In addition, the levels of agents currently in the environment known to pose an appreciable risk to children need to be monitored and child populations at greater risk of environmental exposures identified (IOM, 2004). Aluminum Aluminum (Al) is a toxic metal to all living organisms; it can reach and accumulate in almost every human body organ but the CNS is targeted for these deleterious effects. Select human population can be at risk of Al neurotoxicity, and Al is implicated in neurodegenerative disease etiology. Numerous efforts and accumulating research evidence, in the mechanisms of Al neurotoxicity is still not fully understood (Verstraeten SV, Aimo L, and Oteiza PI, 2008). Yet
  15. 15. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 14 developmental aluminum (Al) toxicity is available from clinical and animal testing studies showing Al toxicity syndrome (encephalopathy, osteomalacia, and anemia) found in uremic children receiving dialysis. Other nondialyzed uremic children receiving Al-based phosphate binders, nonuremic infants receiving parenteral nutrition with Al-containing fluids, and nonuremic infants given high doses of Al antacids manifest this syndrome as well. The number of children in clinical populations that are at risk of Al toxicity is not known and needs to be determined (Golub and Domingo, 1996). The significance of these findings for human health requires better understanding of the amount and bioavailability of Al in food, drinking water, and medications and from sources unique to infants and children such as breast milk, soil ingestion, and medications used specifically by pregnant women and children (Golub and Domingo, 1996). The factors initiating AD, how Al gains access to the brain in Alzheimer’s Disease (AD), and the relative contributions of food, pharmaceuticals and skin absorption, remain unknown. The devastating nature of the disease, lack of an effective treatment or prevention, high human and health care costs; weighed against the cost of eliminating Al from vaccines to reduce exposure, indicates that this action is reasonable and timely (McLachlan, 1995). Formaldehyde Studies on the interactions between formaldehyde and proteins at the molecular level, affect the body’s carrier protein, serum albumin. This binding loosens the skeletal structure of albumin and exposure of the aromatic ring amino acids in the internal hydrophobic region (Wikepedia, 2015). Children may be more vulnerable because of relatively increased minute ventilation per kg and failure to evacuate an area promptly when exposed CNS impacts chronic exposure may be more serious for children because of their potential longer latency period (ATSDR, 2015). Formaldehyde is toxic, allergenic, and carcinogenic to most individuals (ChemSee, 2015). For
  16. 16. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 15 children with a prior history of allergies or reactions, parents should consult their child’s healthcare provider before vaccination (CDC, 2014). Thimerosal (Ethylmercury) Mercury is considered to toxic at any concentration in the body and can cause a very wide range of psychophysiological disturbances (Pizzorno and Murray, 1993). Ethylmercury exposure at high levels can harm the brain, heart, kidneys, lungs, and immune system of people of all ages. The Institute of Medicine (2015) demonstrated that high levels of Ethylmercury in the bloodstream of unborn babies and young children may harm the developing nervous system, making the child less able to think and learn. The World Health Organization reports that the half-life of ethyl mercury is short (<7 days) verses methyl mercury (1.5 months) making exposure to ethyl mercury in blood comparatively brief. Yet, recent studies reported by the Institute of Medicine state that clearance of Ethylmercury in the body may take as long as 30 days (2015). WHO reports that Ethylmercury is safer than methylmerchury as it is actively excreted via the gut (WHO, 2015) but the IOM reports that Ethylmercury is also excreted via the kidneys (2015). The General Advisory Council on Vaccine Safety (GACVS) concluded that the most recent pharmacokinetic and developmental studies do not support concerns over the safety of Thiomersal (Ethylmercury) in vaccines. They stated, “there is no reason on grounds of safety to change current immunization practices with Thiomersal-containing vaccines, as the risks are unproven. However, data for well-nourished neonates born at term cannot necessarily be extrapolated to preterm or malnourished infants” (WHO, 2015). Other researchers emphasized, that the risks associated with low-level exposures to inorganic mercury in the developing brain are unknown, and they describe other research linking persistent inorganic mercury exposure with increased activation of microglia in the brain,
  17. 17. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 16 an effect recently reported in children with autism. Further research was recommended to focus specifically on the biotransformation of Thimerosal and its neurotoxic potential (Barrett, 2005). There are many human developmental and genetic variants along with a growing list of individuals experiencing adverse vaccine reactions and vaccine injury that proof of safety for everyone is next to impossible without pre vaccine testing and individual assessments. The key vaccine preservatives, Aluminum, Thimerosal, and Formaldehyde although placed in minute doses in vaccines, do demonstrate health risks and negative health consequences. Future Implications We need a better understanding of the unique biological actions of Al that may occur during developmental periods, and unique aspects of the developing organism that make it more or less susceptible to Al toxicity (Golub and Domingo, 1996). Ethylmercury may not currently be placed in U.S.A. pediatric vaccines, but the lack of concern by several Vaccine Councils suggest it could return to market to decrease vaccine costs, so further vigilance to keep this out of vaccines is necessary. Although formaldehyde is placed in minute quantities in vaccine, numerous reports of formaldehyde-induced health problems, including poisoning and cancer exist. Minimal quality epidemiological studies and basic data on exposed populations emphasizes the need for extensive formaldehyde studies and its related health effects (Tang , Bai, Duong, Smith, Li , and Zhang 2009) especially on the developing child. Pre-vaccine Testing and Alternative Vaccine Schedules Pre-vaccine testing is not currently performed but would be reasonable before embarking on the recommended vaccine schedule. Testing for MTHFR gene deletions or variants, optimal renal function, and sensitivities/reactivity/allergies to key vaccine ingredients is a necessary option for parents and clinicians to pursue.
  18. 18. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 17 Alternative current vaccine schedules should be considered. Examples include staggering vaccines doses or eliminating certain vaccines for pediatric patients based upon individual medical history. Total abstinence of vaccines in vulnerable populations: family or personal history of adverse vaccine reaction or, genetic mutations, personal history of autoimmune dysfunction, or severe allergies to key vaccine ingredients is reasonable. Although the CDC and WHO report children need to be vaccinated early before their natural immunity wears off; it would seem prudent in populations where children have low birth weight, were preterm, have decreased renal function, are immunocompromised, have autoimmune dysfunction, demonstrate neurodevelopmental disorders, or have genetic contraindications (as in MTHFR gene deletions). Another proposal to the alternative schedule would be to stress breast-feeding up to 2 years of age (or access to breast milk banks for non-breastfed babies) and vaccinate only when the child reaches 24 months of age. Parents could decrease children’s exposure to illness through continued health and hygiene practices, limiting exposure to large crowds, and opting out of daycare centers where acquiring infectious illnesses pose a higher risk. Dr. Rima Laibow, reports there is compelling evidence of vaccine related injury linking neurological injuries and disorders, auto immune disorders, cancer, immune suppression, autism, and lethal consequences to vaccine preservatives. Early and frequent administration of vaccines multiplies this risk substantially (Laibow, 2015). Seneff and collegues state, “there are several signs and symptoms that are significantly more prevalent in vaccine reports after 2000, including cellulitis, seizure, depression, fatigue, pain and death, which are also significantly associated with aluminum-containing vaccines. We propose that children with the autism diagnosis are especially vulnerable to toxic metals such as aluminum and mercury due to insufficient serum sulfate and glutathione. A strong correlation between autism and the MMR vaccine is also
  19. 19. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 18 observed, which may be partially explained via an increased sensitivity to acetaminophen administered to control fever” (Seneff, Davidson, and Liu; 2012). Final Summary Based upon the evidence, caution should be exercised in the following areas: giving vaccines to women prior to conception, during pregnancy, and while nursing. Pre vaccination testing should be performed to assess for genetic variants, neurodevelopmental disorders, decreased renal function, and immune dysfunction. Vaccination delay is recommended for premature and low birth weight infants, and children younger under 2 years of age; as excretion of these preservatives may be poor. Key take away points: Aluminum, Thimerosal (Ethylmercury), and Formaldehyde are standard vaccine preservatives. Formaldehyde is a known carcinogen, immunosuppressive, and mutanogen. Aluminum is neurotoxic, mutanogenic and immunosuppressive. Mercury and Aluminum potentiate each other 100 fold which can occur when multiple vaccines are given together. Although Ethylmercury is not contained in single dose flu vials, potential exists to minimize its effects and to place it back in vaccines. It is also a neurotoxic, mutanogenic, and immunosuppressive. All three preservatives demonstrate increased absorption in utero, in early developmental phases, in vulnerable patients, and those with reduced renal function. Overall, children are more systemically vulnerable to Aluminum, Mercury, and Formaldehyde. Individuals with vulnerable immune systems and genetic variations should be protected from the systemic threats that any of these preservatives possess. As each individual responds uniquely, caution should be taken when mandating compulsory vaccination for the public as multiple simultaneous preservatives appear to pose a valid threat to vulnerable populations. The increase in proven vaccine injuries warrants further comprehensive analysis to study the
  20. 20. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 19 simultaneous impact of these preservatives in different populations. Currently, there is enough evidence to question the safety of the mandated vaccine schedule upon vulnerable populations. Unfortunately, other preservative alternatives have not been introduced into the market.
  21. 21. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 20 Aluminum’s HealthEffects (Table 1) EarlyToxicity: Headaches, colic, drynessof skinandmucous membranes, tendencyfor colds, burning paininthe headrelievedbyfood, heartburn, aversionto meat CNS headaches, memoryloss, lossof Coordination, confusion& disorientation -Inhibits the uptake of Dopamine, Noradrenaline (Norepinephrine), and Serotonin(5-HTP) by nerve cells -Inhibits enzymesinthe brain -Reduces nervous system activitybyblockingthe actionpotentialof nerve cells Blood& Lymph anemia, hemolysis, leukocytosis, porphoria, GI Flatulence, decreasedintestinalactivity Diseases assoc’d w/toxicity Alzheimer’s, ALS, colitis, dental cavities, hypoparathyroidism, kidneydysfunction, liver dysfunction, neuromuscular disorders, Osteomalacia, Parkinson’s disease Formaldehyde’s Systemic Affects (Table 2) System Affects Metabolism Absorptionfrom the respiratorytract is veryrapid;absorptionfromthe gastrointestinal tract is alsorapid, but maybe delayedbyingestionwith food. Once absorbed, formaldehyde is metabolizedto formic acid, which maycause acid-base imbalance anda number of other systemic effects. Accumulationof formic acid can cause ananion-gapacid-base imbalance. Respiratory Fairlylow concentrations offormaldehyde canproduce rapid onset ofnoseand throat irritation, causing cough, chest pain, shortnessof breath, andwheezing. Higher exposures can cause significant inflammation of the lower respiratorytract, resultinginswellingof the throat, inflammation ofthe windpipe andbronchi, narrowing of the bronchi, inflammationof the lungs, andaccumulationof fluidinthe lungs. Pulmonary injurymaycontinue to worsenfor 12 hours or more after exposure. Childrenmaybe more vulnerable because of relativelyincreasedminute ventilationper kg andfailure to evacuate anareapromptlywhen exposed. GI Ingestionof aqueous solutions of formaldehyde canresult insevere corrosive injuryto the esophagus and stomach. Nausea, vomiting, diarrhea, abdominal pain, inflammationof the stomach, andulcerationand perforationof the oropharynx, epiglottis, esophagus, andstomach mayoccur. Bothformaldehyde andthe methanol stabilizer are easilyabsorbed andcancontribute to systemic toxicity. Immunologic In persons whohave beenpreviouslysensitized, inhalation and skin contact maycause various skin disorders, asthma-like symptoms, anaphylactic reactions and, rarely, hemolysis. The immune system in children continues to developafter birth, and thus, childrenmaybe more susceptible to certainchemicals. CNS Malaise, headache, sleepingdisturbances, irritability, and impairment ofdexterity, memory, andequilibrium mayresult from a single, highlevel, exposure to formaldehyde. Increased prevalence of headache, depression, mood changes, insomnia, irritability, attentiondeficit, andimpairment of dexterity, memory, and equilibrium have been reported to result from long-term exposure. Chronic exposure maybe more serious for childrenbecause of their potential longer latencyperiod. Reproductive There have been reports of menstrual disorders inwomen occupationallyexposed to formaldehyde; Studies in experimental animals have reportedsome effects on spermatogenesis;has beenshownto have genotoxic properties in humanand laboratoryanimal studiesproducingsister chromatidexchange and chromosomal aberrations;Specialconsiderationregardingthe exposure of pregnant womenis warranted, since formaldehyde has beenshownto be a genotoxin;thus, medical counselingis recommendedfor the acutely exposed pregnant woman. Chronic exposure: The major concerns of repeatedformaldehyde exposure are sensitization and cancer. Insensitized persons, formaldehyde cancause asthma andcontact dermatitis.
  22. 22. Running Head: Safety Concerns Regarding Pediatric Vaccine Preservatives 21 Vaccine IngredientsTable 3 Name/Company Vaccine Ingredients Acel-ImmuneDTaP Wyeth-Ayerst #800.934.5556 diphtheria -tetanus - pertussis diphtheria and tetanus toxoids and acellular pertussis adsorbed plus: formaldehyde, aluminum hydroxide,aluminum phosphate, thimerosal, and polysorbate80 (Tween-80) andgelatin Act HIB-Haemophilus influenza Type B ConnaughtLaboratories 800.822.2463 Haemophilus influenza Type B Haemophilus influenza Type B Plus: polyribosylribitolphosphate, ammonium sulfate, formalin,and sucrose Attenuvax- Merck & Co., Inc.800-672-6372 measles measles livevirus Plus: neomycinsorbitolhydrolized gelatin, chick embryo Biavax- Merck & Co., Inc.800-672-6372 rubella rubella live virus Plus: neomycin, sorbitol,hydrolizedgelatin, human diploid cells from aborted fetal tissue DPT (diphtheria -tetanus – pertussis) GlaxoSmithKline800.366.8900 X 5231 diphtheria -tetanus - pertussis diphtheria and tetanus toxoids and acellular pertussis adsorbed plus: formaldehyde, aluminum phosphate,ammonium sulfate,and thimerosal washedsheep RBCs Engerix-B GlaxoSmithKline800.366.8900 X 5231 recombinant hepatitis B genetic sequence ofthehepatitis B virus that codes for the surfaceantigen (HbSAg), cloned into GMO yeast plus: aluminum hydroxide,andthimerosal Fluvirin Medeva Pharmaceuticals 888.MEDEVA716.274.5300 Flu influenza virus Plus: neomycin, polymyxin beta-propiolactonechick embryonicfluid FluShield Wyeth-Ayerst 800.934.5556 Flu trivalent influenza virus types A&B Plus: gentamicinsulphate, formadehyde,thimerosal, and polysorbate 80 (Tween-80) Havrix GlaxoSmithKline800.366.8900 X 5231 hepatitis A hepatitis Avirus plus: formalin, aluminum hydroxide,2-phenoxyethanol, andpolysorbate20 residualMRC5 proteins -humandiploid cells from aborted fetal Haemophilus influenza Type B Wyeth-Ayerst 800.934.5556 HiB Titer tissue Haemophilus influenza Type B Plus: polyribosylribitol phosphate, yeast ammoniumsulfate, thimerosal,and chemically definedyeast-based medium MMR- Merck & Co., Inc.800.672.6372 measles -mumps - rubella measles, mumps,rubella livevirus plus: neomycin,sorbitol, hydrolizedgelatin, chick embryonic fluid,andhuman diploid cells from aborted fetal tissue Menomune ConnaughtLaboratories 800.822.2463 -meningococcal freeze-dried polysaccharideantigens from Neisseria meningitidis bacteria Plus: thimerosal lactose ProQuad Merck & Co., Inc.800.672.6372 measles, mumps, rubella and varicella live measles (Enders'attenuated Edmonston), mumps (JerylLynnTM), rubella (Wistar RA 27/3), and varicella (oka/Merck) strains ofviruses Proquad(cont.) Plus: neomycin, monosodium L-glutamate(MSG), potassium chloride, potassium phosphatemonobasic, potassiumphosphate dibasic, sodium bicarbonate, sodiumphosphatedibasic, sorbitol,and sucrose humanalbumin, human diploid cells, residualcomponents ofMRC-5 cells including DNAand proteins, bovine serum, hydrolized gelatin,andchickenembryo Recombivax Merck & Co., Inc.800.672.6372 recombinant hepatitis B genetic sequence ofthehepatitis B virus that codes for thesurfaceantigen (HbSAg), cloned into GMO yeast Plus: aluminum hydroxide,and thimerosal Tripedia Aventis Pasteur USA 800.VACCINE -diphtheria -tetanus - pertussis Corynebacteriumdiphtheriaeand Clostridium tetanitoxoids and acellular Bordetella pertussis adsorbed Plus: aluminum potassiumsulfate, formaldehyde, thimerosal,andpolysorbate 80 (Tween-80) Typhim Aventis Pasteur USASA 800.VACCINE Vi-typhoid cell surfaceVi polysaccharide fromSalmonella typhi Ty2 strain Plus: aspartame, phenol,and polydimethylsiloxane (silicone) Varivax- Merck & Co., Inc.800.672.6372 chickenpox varicella livevirus Plus: neomycinphosphate, sucrose, and monosodium glutamate(MSG) processed gelatin, fetal bovine serum, guinea pig embryo cells, albumin from human blood,andhuman diploidcells fromaborted fetaltissue
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