Childhood Vaccinations – Necessary or Overkill?

Some parents of children with autism believe that there is a link between measles, mumps, rubella (MMR) vaccine and autism.However, there is no sensible reason to believe that any vaccine can cause autism or any kind of behavioral disorder. Typically, symptoms of autism are first noted by parents as their child begins to have difficulty with delays in speaking after age one. MMR vaccine is first given to children at 12-15 months of age. Since this is also an age when autism commonly becomes apparent, it is not surprising that autism follows MMR immunization in some cases. However, by far the most logical explanation is coincidence, not cause-and-effect.If measles vaccine or any other vaccine causes autism, it would have to be a very rare occurrence, because millions of children have received vaccines without ill health effects. The only "evidence" linking MMR vaccine and autism was published in the British journal Lancet in 1998 . An editorial published in the same issue, however, discussed concerns about the validity of the study . Based on data from 12 patients, Dr. Andrew Wakefield (a British gastroenterologist) and colleagues speculated that MMR vaccine may have been the possible cause of bowel problems which led to a decreased absorption of essential vitamins and nutrients which resulted in developmental disorders like autism. No scientific analyses were reported, however, to substantiate the theory. Whether this series of 12 cases represent an unusual or unique clinical syndrome is difficult to judge without knowing the size of the patient population and time period over which the cases were identified.If there happened to be selective referral of patients with autism to the researchers' practice, for example, the reported case series may simply reflect such referral bias. Moreover, the theory that autism may be caused by poor absorption of nutrients due to bowel inflammation is senseless and is not supported by the clinical data. In at least 4 of the 12 cases, behavioral problems appeared before the onset of symptoms of inflammatory bowel disease. Furthermore, since publication of their original report in February of 1998, Wakefield and colleagues have published another study in which highly specific laboratory assays in patients with inflammatory bowel disease, the posited mechanism for autism after MMR vaccination, were negative for measles virus .Other recent investigations also do not support a causal association between MMR (or other measles-containing vaccines) and autism or inflammatory bowel disease (IBD) . In one investigation, a Working Party on MMR Vaccine of the United Kingdom's Committee on Safety of Medicines (1999) was charged with the evaluation of several hundred reports, collected by a firm of lawyers, of autism, Crohn's disease, or similar disorders developing after receipt of MMR or MR vaccines. The Working Party conducted a systematic, standardized review of parental and physician information. Although acknowledging that it is impossible to prove or refute the suggested associations (because of variable data quality, biased selection of cases, and lack of a control group), the Working Party concluded that the information available "... did not support the suggested causal associations or give cause for concern about the safety of MMR or MR vaccines." In March 2000, a Medical Research Council report concludes that between March 1998 and September 1999 no new evidence had suggested a causal link between MMR and autism or IBD . The American Medical Association has reached the same conclusion.A study by Taylor and colleagues provides population-based evidence that overcomes many of the limitations faced by the Working Party and by Wakefield and colleagues . The authors identified all 498 known cases of autism spectrum disorders (ASD) in certain districts of London born in 1979 or later and linked them to an independent regional vaccination registry. ASD includes classical autism, atypical autism, and Asperger's syndrome, but the results were similar when cases of classical autism were analyzed separately. The authors noted:The first diagnosis of autism or initial signs of behavioral regression were not more likely to occur within time periods following vaccination than during other time periods.A study of the population of children in two communities in Sweden also found no evidence of an association between MMR vaccination and autism . That study found no difference in the prevalence of autism in children born after the introduction of MMR vaccination in Sweden compared with children born before.In January 1990, an Institute of Medicine committee examining possible health effects associated with DPT vaccine concluded that there was no evidence to indicate a causal relation between DPT vaccine or the pertussis component of DPT vaccine and autism . Also, data obtained from CDC's Monitoring System for Adverse Events Following Immunization (MASAEFI) system, showed no reports of autism occurring within 28 days of DPT immunization from 1978-1990, a period in which approximately 80.1 million doses of DPT vaccine were administered in the United States. From January 1990 through February 1998, only 15 cases of autism behavior disorder after immunization were reported to the Vaccine Adverse Events Reporting System (VAERS). Because of the small number of reports over an 8-year period, the cases reported are likely to represent unrelated chance occurrences that happened around the time of vaccination.The most frequent vaccines cited in the reports were diphtheria, tetanus, pertussis (DPT), oral polio vaccine (OPV), and MMR. Other vaccines reported as having a possible association with autism were Haemophilus influenzae type B and Hepatitis B.Although the possible association with MMR vaccine has received much public and political attention and there are many who have derived their own conclusions based on personal experiences, the available evidence does not support the hypothesis that MMR vaccine causes autism or associated disorders or IBD. Separate administration of measles, mumps, and rubella vaccines to children provides no benefit over administration of the combination MMR vaccine and would result in delayed or missed immunizations.

but there has been a recent increase due to resistance of parents to the MMR vaccine

Because manufacturers stopped using thimerosal in children’s vaccines in 2000, few children now under age four have ever received a thimerosal-containing vaccine. Even those born to Rh-negative mothers (who received at least one dose of thimerosal-containing RhoGam during pregnancy) have gotten far less thimerosal than older children. If thimerosal were a major cause of autism, we should see a drop in autism incidence, which has yet to materialize.

Denmark mandated removal of thimerosal from vaccines in 1992. Even allowing for continued use of thimerosal-containing stocks of vaccine, Danish children were thimerosal-free by 1995. Autism prevalence in Denmark has risen in exactly the same fashion as in the United States and the United Kingdom.

When potent natural substances are discovered, drug companies try to isolate and synthesize the active chemical in order to provide a reliable supply. They also attempt to make derivatives that are more potent, more predictable, and have fewer side effects. In the case of digitalis, derivatives provide a spectrum of speed and duration of action. Digitalis leaf is almost never used today because its effects are less predictable. Many herbs contain hundreds or even thousands of chemicals that have not been completely cataloged. Some of these chemicals may turn out to be useful as therapeutic agents, but others could well prove toxic.

In the United States, herbs intended for preventive or therapeutic use would be regulated as drugs under federal laws. To evade the law, these products are marketed as "foods" or "dietary supplements" without health claims on their labels. Since herbs are not regulated as drugs, no legal standards exist for their processing, harvesting, or packaging. In many cases, particularly for products with expensive raw ingredients, contents and potency are not accurately disclosed on the label. Many products marked as herbs contain no useful ingredients, and some even lack the principal ingredient for which people buy them. Surveys have found have found that the ingredients and doses of several products varied considerably from brand to brand.

To make a rational decision about an herbal product, it would be necessary to know what it contains, whether it is safe, and whether it has been demonstrated to be as good or better than pharmaceutical products available for the same purpose. For most herbal ingredients this information is incomplete or unavailable. Even worse, most published information about herbs is unreliable. The late Varro E. Tyler, Ph.D., former dean of the Purdue University School of Pharmacy and a leading authority on pharmacognosy (the science of medicines from natural sources), observed:More misinformation about the safety and efficacy of herbs is reaching the public currently than at any previous time, including the turn-of-the-century heyday of patent medicines. The literature promoting herbs includes pamphlets, magazine articles, and books ranging in quality from cheaply printed flyers to elaborately produced studies in fine bindings with attractive illustrations. Practically all of these writings recommend large numbers of herbs for treatment based on hearsay, folklore, and tradition. The only criterion that seems to be avoided in these publications is scientific evidence. Some writings are so comprehensive and indiscriminate that they seem to recommend everything for anything. Even deadly poisonous herbs are sometimes touted as remedies, based on some outdated report or a misunderstanding of the facts. Particularly insidious is the myth that there is something almost magical about herbal drugs that prevents them, in their natural state, from harming people [8].

A study published in 2002 found that many sites located by searching for "herbs" and "cancer cure" contained illegal claims. [9] Dr. Stephen Barrett advises consumers to ignore advice from anyone who has a financial interest in the sale of dietary supplements, herbs, or homeopathic products.

Researchers from Harvard have evaluated claims made on 443 Web sites located by searching for information about eight widely used herbal supplements (ginkgo biloba, St John's wort, echinacea, ginseng, garlic, saw palmetto, kava kava, and valerian root). [10]. The researchers concluded:Among 443 sites, 338 (76%) were retail sites either selling product or directly linked to a vendor.273 (81%) of the 338 retail Web sites made 1 or more health claims, with 149 (55%) claiming to treat, prevent, diagnose, or cure specific diseases.More than half (153/292; 52%) of sites with a health claim omitted the legally required standard federal disclaimer.Nonretail sites were more likely than retail sites to include literature references, but only 52 (12%) of the 443 Web sites provided referenced information without a link to a distributor or vendor.Consumers may be misled by vendors' claims that herbal products can treat, prevent, diagnose, or cure specific diseases, despite regulations prohibiting such statements. Physicians should be aware of this widespread and easily accessible information.More effective regulation is required to put this class of therapeutics on the same evidence-based footing as other medicinal products.