I’ve told you in the past that when parents choose to not vaccinate their children, not only are their children at risk, but so are other children in the community. Here’s more proof of that. Continue reading
The anti-vaccination movement has no better friends than in the alternative medicine world. In the Massachusetts study mentioned in my last blog, less than one-third of the homeopaths recommended immunization, and almost 10 percent actively opposed immunization. In England, the most common reason given for not having children immunized is the recommendation parents receive from a homeopath. Continue reading
Despite overwhelming evidence that there is NO association between any vaccine in particular, or vaccines in general, and autism, just a slim majority of Americans – 52 percent – think vaccines don’t cause autism, a new Harris Interactive/HealthDay poll found. Conversely, 18 percent are convinced that vaccines, like the measles-mumps-rubella (MMR) vaccine, can cause the disorder, and another 30 percent aren’t sure. Continue reading
In an op-ed in the New York Times, Michael Willrich, an associate professor of history at Brandeis University, writes , “Despite the overwhelming evidence to the contrary, roughly one in five Americans believes that vaccines cause autism—a disturbing fact that will probably hold true even after the publication, in a British medical journal, of a report thoroughly debunking the 1998 paper that began the vaccine-autism scare.” Continue reading
In a number of previous blogs, I’ve discussed vaccine myths, in an attempt to bring you information about vaccines that is reliable, trustworthy, and medically accurate. I recently found this review of the myth that vaccines cause autism and wanted to share it with you. It’s a discussion between Robert Dachs, MD, FAAFP (Ellis Hospital Family Medicine Residency Program, Schenectady, New York), Andrea Darby-Stewart, MD (Scottsdale Healthcare, Scottsdale, Arizona), and Mark Graber, MD, FACEP (University of Iowa Carver College of Medicine, Iowa City, Iowa) and was published in the American Family Physician (2010 Sep 15;82(6):586-592).
Are childhood vaccinations associated with subsequent development of autism?
Bob: In 1998, a British gastroenterologist, Dr. Andrew Wakefield, published a report in the Lancet on eight children who developed symptoms of autism within one month of receiving the measles, mumps, and rubella (MMR) vaccine.1 Since then, the media, advocacy groups, and celebrities have promulgated the link between childhood vaccinations (particularly the MMR vaccine) and the development of autism. But, is it true?
This month’s article clearly outlines the epidemiologic and biologic studies that should reassure physicians and parents that there is no connection between childhood vaccinations and autism.2 For the family physician, the data in this article are impressive and can be used to counter most parental concerns.
What does this article say?
Bob: This article reviews the three most commonly proposed hypotheses for vaccine-induced development of autism:
- the MMR vaccine damages the intestinal lining, allowing the entrance of encephalopathic proteins;
- thimerosal induces central nervous system toxicity; and
- multiple vaccinations overwhelm and weaken the immune system.
This article looks at the genesis of each theory and the data that debunk them.2
In regard to the MMR vaccine, Dr. Wakefield noted lymphoid nodular hyperplasia on endoscopy in eight children with gastrointestinal symptoms and signs of autism within one month of receiving the MMR vaccine. He then postulated that this intestinal inflammation allowed nonpermeable peptides into the bloodstream, subsequently affecting brain development.1
There are many holes in this argument.
- First, this was a self-referred cohort without a control group.
- Second, in Great Britain, approximately 50,000 children one to two years of age receive the MMR vaccine each month; this is a time when autism typically presents, making this likely a coincidental association.
- Third, the MMR vaccine has not been found to cause chronic intestinal inflammation.
- Fourth, no toxic encephalopathic proteins traveling from the intestine to the brain have ever been identified. Instead, genes that code for endogenous proteins, which influence neuronal synapse function, have been identified in children with autism.3
Mark: The most glaring flaw in the argument connecting an MMR-induced intestinal hyperplasia and subsequent autism development is assigning cause and effect to a potential association. Association should not be confused with causation.
Without a control group in the original study by Dr. Wakefield, it is imprudent to even suggest that there is an association between the MMR vaccine and intestinal lymphoid hyperplasia. Large-scale studies are often needed to demonstrate whether an association is statistically present.
Bob: The authors of this month’s article reviewed 13 such large-scale studies that demonstrate no association between the MMR vaccine and autism.2 These are separated into three types of studies:
Ecologic (studies comparing vaccination rates with autism diagnosis). In California and the United Kingdom, the diagnosis of autism increased through the 1980s and 1990s, yet MMR vaccination rates remained stable during this time.4,5 In Quebec, Canada, autism rates increased despite a decrease in MMR vaccination.6
Retrospective observational (studies comparing vaccination status with autism diagnosis using national registries). The best study was one conducted in Denmark in which 440,655 children born between 1991 and 1998 who received the MMR vaccine were compared with 97,648 children born during the same years who were not given the MMR vaccine. There were no differences in autism rates between the two groups.7
Prospective observational (a long-term vaccination project allows researchers to prospectively record adverse events associated with the MMR vaccine). In Finland, 1.8 million children were prospectively followed after MMR vaccination, and no cases of vaccine-induced autism were recorded.8
Andrea: To further refine the concept of association and causation, there are times when an association does represent a cause and effect. A good example is smoking and lung cancer rates. Clearly, smoking is associated with increased lung cancer rates, and a randomized, placebo-controlled trial is not needed to prove this. The association between smoking and lung cancer meets all of the following criteria: strength and consistency of the scientific data; existence of a temporal relationship (between smoking history and lung cancer); existence of a biologic gradient (increased exposure results in increased risk); a scientifically plausible association; and experimental interventions that work (smoking cessation decreases cancer rates).9 However, in the case of MMR vaccine–induced autism, none of these criteria are present. The data, in fact, overwhelmingly support no association.
Bob: Let’s briefly look at the second hypothesis of thimerosal-induced neurotoxicity. Thimerosal is an antibacterial agent that has been used in multidose vaccine preparations for more than 50 years. It is 50 percent ethyl mercury by weight. However, mercury poisoning has a distinctly different presentation than autism. The CDC has also demonstrated that the mercury in vaccines has not resulted in any subtle signs or symptoms of mercury poisoning.10 The authors of this month’s article review seven large-scale studies—again, ecologic, retrospective, and prospective studies—all demonstrating no association between thimerosal and autism.2
Mark: And, by the way, live vaccines like MMR do not contain thimerosal.
Bob: The third and final theory suggests that the simultaneous administration of multiple vaccines overloads the immune system, triggering autism in a susceptible host. However, because of advances in protein chemistry and DNA technology, the immunologic load has decreased from more than 3,000 immunologic components in the seven available vaccines in 1980 to less than 200 in the 14 recommended vaccines today.2
Andrea: Two more points: (1) an infant’s immune system is capable of handling the thousands of antigens it is exposed to early in life; and (2) autism is not an autoimmune disease. Therefore, this theory has no credibility.
Should we believe this study?
Bob: This month’s article clearly provides the science and statistics to dispel the theory that childhood vaccinations induce autism.2 A Cochrane review came to the same conclusion in October 2005.11
Andrea: Large-scale studies, smaller studies, retrospective studies, prospective studies, and case-control studies (you name it) all come to the same conclusion: there is no connection between vaccines and autism. The only outlier is Dr. Wakefield’s study, which suggests this possible link.1
Mark: Lo and behold, 10 of the 13 authors of Dr. Wakefield’s Lancet article have since publicly retracted the interpretation they reported.12 The editor of the Lancet has acknowledged that, had they appreciated the full context of Dr. Wakefield’s study, “… publication would not have taken place the way that it did.”13 On further review, the Lancet also recently published an official retraction of Dr. Wakefield’s study (http://press.thelancet.com/wakefieldretraction.pdf).
What should the family physician do?
Bob: Get this month’s article. It’s an easy read. Keep it handy for when parents are apprehensive about immunizing their child.
Andrea: A national survey conducted in 2003 to 2004 indicated that more than one fourth of all U.S. parents were either unsure of vaccine safety or refused or delayed vaccination of their children because of safety concerns. However, the most important take-home point from that survey was that the parents who changed their minds and immunized their children did so because of information and assurance provided by their health care professional.14 Indeed, we do make a difference!
Mark: Understand the consequences if we just give in to fear and myths. In 2008, only three fourths of preschool children in the United Kingdom received two doses of the MMR vaccine. The result: measles infection rates have reached more than 1,000 cases per year, the highest since monitoring began in 1995.15
There are no epidemiologic or biologic studies that support a connection between childhood vaccinations and autism.
An association does not confer causation.
Multiple criteria should be examined when considering if an association implies causation, including strength, consistency, specificity, temporality, dose-response relationship, plausibility, coherence, experimental evidence, and analogy.9
- Wakefield AJ, Murch SH, Anthony A, et al. Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children [retraction published in Lancet. 2010;375(9713):445]. Lancet. 1998;35(9103):637–641.
- Gerber JS, Offit PA. Vaccines and autism: a tale of shifting hypotheses. Clin Infect Dis. 2009;48(4):456–461.
- Sutcliffe JS. Genetics: insights into the pathogenesis of autism. Science. 2008;321(5886):208–209.
- Dales L, Hammer SJ, Smith NJ. Time trends in autism and in MMR immunization coverage in California. JAMA. 2001;285(9):1183–1185.
- Kaye JA, del Mar Melero-Montes M, Jick H. Mumps, measles, and rubella vaccine and the incidence of autism recorded by general practitioners: a time trend analysis. BMJ. 2001;322(7284):460–463.
- Fombonne E, Zakarian R, Bennett A, Meng L, McLean-Heywood D. Pervasive developmental disorders in Montreal, Quebec, Canada: prevalence and links with immunizations. Pediatrics. 2006;118(1):e139–e150.
- Madsen KM, Hviid A, Vestergaard M, et al. A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med. 2002;347(19):1477–1482.
- Peltola H, Patja A, Leinikki P, Valle M, Davidkin I, Paunio M. No evidence for measles, mumps, and rubella vaccine–associated inflammatory bowel disease or autism in a 14-year prospective study. Lancet. 1998;351(9112):1327–1328.
- Simon S. Children’s Mercy Hospitals and Clinics. Causation. http://www.childrens-mercy.org/stats/ask/causation.asp. Accessed January 8, 2010.
- Thompson WW, Price C, Goodson B, et al.; Vaccine Safety Datalink Team. Early thimerosal exposure and neuropsychological outcomes at 7 to 10 years. N Engl J Med. 2007;357(13):1281–1292.
- Demicheli V, Jefferson T, Rivetti A, Price D. Vaccines for measles, mumps and rubella in children. Cochrane Database Syst Rev. 2005;(4):CD004407.
- Murch SH, Anthony A, Cassen DH, et al. Retraction of an interpretation. Lancet. 2004;363(9411):750.
- Horton R. The lessons of MMR. Lancet. 2004;363(9411):747–749.
- Gust DA, Darling N, Kennedy A, Schwartz B. Parents with doubts about vaccines and reasons why. Pediatrics. 2008;122(4):718–725.
- Health Protection Agency. Measles figures soar. http://www.hpa.org.uk/webw/HPAweb&HPAwebStandard/HPAweb_C/1227774034336?p=1204186170287. Accessed December 6, 2009.
For more information on EBM terms, see the EBM Toolkit here.
A new review is reporting that fewer tears are shed by babies when they get a sweet solution before injections. A report in HealthDay News says, “A sugar solution appears to help babies tolerate immunizations and get through the pain, researchers have found.” I’ve been doing this for years in my practice, but wanted to be sure that you knew of this new review. In fact, the approach works so well that the new report is recommending that doctors and nurses consider giving a sweet solution to all babies before immunization in children 1 month to 1 year old.
Previous research has shown that a small amount of sucrose or glucose — a few drops to half a teaspoon — in a solution can reduce pain. In the new report, released in Archives of Disease in Childhood, researchers from Canada, Australia and Brazil reviewed findings from 14 studies that examined 1,674 injections given to children 1 year or younger.
In 13 of the studies, babies who were given a bit of sugary solution — compared with those given water or nothing — were found to cry less after immunization. Babies given 30 percent glucose in the solution were about half as likely to cry, the study found.
“Health-care professionals responsible for administering immunizations should consider using sucrose or glucose during painful procedures,” study author Denise Harrison, of the Hospital for Sick Children in Toronto, and her colleagues concluded. “This information is important for health-care professionals working with infants in both inpatient and outpatient settings, as sweet solutions are readily available, have a very short onset of time to analgesia, are inexpensive and are easy to administer.”
Misinformation About Vaccine Safety Puts Kids at Risk of IllnessAbout one-third of U.S. parents surveyed had delayed or refused early childhood immunizations. As I’ve told you in previous blogs, this is a decision that can potentially harm your child and his or her friends. Here’s a report from HealthFinder that confirms my beliefs:
Physicians report that children who don’t receive recommended vaccine doses by the time they’re 2 years old are at risk of developing a variety of diseases. But some anti-vaccine activists contend that the shots can cause side effects, including autism, although health officials say repeated studies have failed to uncover such a link.
For this study, researchers analyzed the results of a 2008 national survey of parents and health-care providers and found that almost one-third of U.S. parents surveyed delayed vaccines for their very young children and 12 percent simply refused to have their children immunized, possibly making them more vulnerable to illness.
Thirty-one percent of parents with children aged 24 to 35 months reported that they’d delayed vaccine doses on purpose in 2008. In fact, the percentage of parents who either delayed or refused to immunize their children grew from 22 percent in 2003 to 39 percent in 2008.
Not all the non-vaccinating parents oppose immunization; 44 percent of the parents who didn’t vaccinate their children on schedule said their child was ill. In addition, 27 percent thought too many shots were recommended; 26 percent questioned whether vaccines were effective; 25 percent were concerned about autism; and 24 percent said they feared side effects or thought vaccines weren’t entirely safe.
The study was scheduled to be presented Tuesday at the Pediatric Academic Societies’ annual meeting in Vancouver, British Columbia, Canada. (SOURCE: American Academy of Pediatrics, news release, May 4, 2010)
Here are some of my other popular blogs on the topic:
- Misinformation About Vaccine Safety Puts Kids at Risk of Illness
- Doctors Debate Delayed Vaccine Schedule
- Survey Shows Parents Still Worry Unnecessarily About Vaccines
- More on the Risks of Not Vaccinating Your Children
- Parents continue to have unwarranted fears and delusions about pediatric vaccines
Also, I did a popular series on VACCINE MYTHS. You can review the series starting with the first one:
The New York Times, in Vital Signs, reports that one in four parents “think some vaccines cause autism in healthy children, and nearly one in eight have refused at least one recommended vaccine,” according to a study published online March 1 in the journal Pediatrics.
The USA covered the story with this article:
Most parents continue to follow the advice of their children’s doctors, according to a study based on a survey of 1,552 parents. Extensive research has found no connection between autism and vaccines.
“Nine out of 10 parents believe that vaccination is a good way to prevent diseases for their children,” said lead author Dr. Gary Freed of the University of Michigan. “Luckily their concerns don’t outweigh their decision to get vaccines so their children can be protected from life-threatening illnesses.”
In 2008, unvaccinated school-age children contributed to measles outbreaks in California, Illinois, Washington, Arizona and New York, said Dr. Melinda Wharton of the U.S. Centers for Disease Control and Prevention. Thirteen percent of the 140 who got sick that year were hospitalized.
“It’s fortunate that everybody recovered,” Wharton said, noting that measles can be deadly. “If we don’t vaccinate, these diseases will come back.”
Fear of a vaccine-autism connection stems from a flawed and speculative 1998 study that recently was retracted by a British medical journal. The retraction came after a council that regulates Britain’s doctors ruled the study’s author acted dishonestly and unethically.
The new study is based on a University of Michigan survey of parents a year ago, long before the retraction of the 1998 study. However, much has been written about research that has failed to find a link between vaccines and autism. Mainstream advocacy groups like Autism Speaks strongly encourage parents to vaccinate their children.
“Now that it’s been shown to be an outright fraud, maybe it will convince more parents that this should not be a concern,” said Freed, whose study appears in the April issue of Pediatrics, released Monday.
Some doctors are taking a tough stand, asking vaccine-refusing parents to find other doctors and calling such parents “selfish.”
A statement from a group practice near Philadelphia outlines its doctors’ adamant support for government recommended vaccines and their belief that “vaccines do not cause autism or other developmental disabilities.”
“Furthermore, by not vaccinating your child you are taking selfish advantage of thousands of other who do vaccinate their children … We feel such an attitude to be self-centered and unacceptable,” the statement says, urging those who “absolutely refuse” vaccines to find another physician.
“We call it the manifesto,” said Dr. Bradley Dyer of All Star Pediatrics in Lionville, Pa.
Dozens of doctors have asked to distribute the statement, Dyer said, and only a handful of parents have taken their children elsewhere.
“Parents have said, ‘Thank you for saying that. We feel much better about it,'” Dyer said.
The new study is based on an online survey of parents with children 17 and younger. It used a sample from a randomly selected pool of nationally representative participants. Households were given Internet access if they didn’t already have it to make sure families of all incomes were included. Vaccines weren’t mentioned in the survey invitation and vaccine questions were among others on unrelated topics.
Twenty-five% of the parents said they agreed “some vaccines cause autism in healthy children.” Among mothers, 29% agreed with that statement; among fathers, it was 17%.
Nearly 12% of the parents said they’d refused a vaccine for their children that a doctor recommended. Of those, 56% said they’d refused the relatively new vaccine against human papillomavirus, or HPV, which can cause cervical cancer. Others refused vaccines against meningococcal disease (32%), chickenpox (32%) and measles-mumps-rubella (18%).
Parents who refused the HPV vaccine, recommended for girls since 2006, cited various reasons.
Parents who refused the MMR vaccine, the shot most feared for its spurious autism link, said they’d read or heard about problems with it or felt its risks were too great.
The findings will help doctors craft better ways to talk with parents, said Dr. Gary S. Marshall of the University of Louisville School of Medicine and author of a vaccine handbook for doctors.
“For our children’s sake, we have to think like scientists,” said Marshall, who was not involved in the new study. “We need to do a better job presenting the data so parents understand how scientists have reached this conclusion that vaccines don’t cause autism.”
- Lancet formally retracts paper linking vaccine to autism
- Chelation therapy for autism not only potentially harmful, it’s based on faulty premise
- Many autism therapies are unproven and risky
- Supposed ‘miracle drug’ for autism called ‘junk’
- Parents continue to have unwarranted fears and delusions about pediatric vaccines
- Special court rules against families who claim vaccines caused autism
- U.S. study clears measles vaccine of autism link
- Fringe Autism Treatment Could Get Federal Study
- Does the MMR vaccine cause autism? A redux.
- Vaccine Myth #1: Vaccines Cause Autism
My blog, “Radio Listeners ‘Angry as Hornets’ About Dr. Walt’s Comments on Childhood Vaccination” raised howls of protest from blog constituents. Many of those who wrote comments simply do not understand how safe and effective vaccines are. They don’t seem to understand how vaccines are tested and then how throughly they are followed once licensed. If you’re interested in the truth about vaccine safety, and not the spin, read on. With this information you’ll not only share my (and virtually the entire medical world’s) about the safety of vaccines, but you’ll be able to help others who have been, unfortunately, indoctrinated (and, in some cases, brainwashed) by the fringe and fanatical antivaccine crazies.
Read More: Continue reading