Autism and Vaccine

Biology in Society Senior Seminar

Bryn Mawr College, Fall 2010
Session 4B:
Vaccination and autism

• Vaccination: Why do we do it?
• The anti-vaccination movement
• Andrew Wakefield and his article in the Lancet
• The Science seems concrete…but the anti-vaccination movement persists

What we are protected from with the MMR vaccine
Caused by a virus in the paramyxovirus family, Measles is a highly infectious disease that is responsible for the largest amount of child deaths worldwide. Despite the availability of this vaccine, 197, 000 deaths resulted from measles globally in 2007. About 10 days after exposure, an infected individual will run a fever and have other typical flu-like symptoms (cough, runny-nose, red eyes etc) as well as small white spots in the mouth on the cheeks. A rash will erupt after a few days appearing first on the face and neck, later spreading over the body. Most worrying are the complications that can occur with the measles. Encephalitis (swelling of the brain caused by infection), blindness, pneumonia and diarrhea can all occur as a result of contracting the virus (WHO-Measles).
The vaccine also provides protection against a viral infection called the Mumps. Fever, headache, fatigue and characteristic swelling of the salivary glands are the most commonly experienced symptoms (CDC- Mumps). However, much rarer and more serious complications can arise such as encephalitis, inflammation of the testes, ovaries and breasts (Mumps, 2008). Mumps is contagious from about 3 days before, to 9 days after the onset of symptoms (CDC-Mumps). The virus can be caught by exposure to a coughing infected individual, or through other respiratory fluids (Medicine plus). There is currently no treatment for Mumps and while it is not as deadly as the measles, it certainly makes sense to avoid transmitting the disease altogether by use of the effective vaccination available.
The third disease the MMR vaccine offers protection against is the Rubella virus (the German Measles). Spread by coughing and sneezing, this virus causes fever and a rash for several days (CDC-Rubella).
 
The beginning of the anti-vaccination movement:
Ø  Ironically, the success of vaccines in preventing deaths has also contributed to the increasing numbers of parents that choose not to vaccinate. Thanks to the MMR vaccine, millions of lives are saved. Many parents who decide against vaccination have never witnessed something like the measles kill a child. Inexperience in this regard renders parents inappropriately dismissive of something that’s “just the measles”.  (Calandrillo, (Abstract Only)).
-Frontline: The Vaccine War (15:20-17:50) Cases of vaccine preventable diseases.
Ø  The CDC website has a common questions section containing an interesting topic entitled; “what would happen if we stopped immunization?” It states that between 1935 and 1963, deaths due to measles were averaged to be 450 annually (CDC -What Would Happen). To give a clear idea of the effect a loss of herd immunity could have, the CDC estimates that if we stopped vaccinating altogether, we could expect measles deaths to rise to about 2.7 million per year worldwide (CDC- What Would Happen). While this is an extreme example of loss of immunization, the point is still the same; as immunization rates dwindle, the rate of measles will increase. Between January and April 25th of 2008, 64 cases of measles were reported in the US. These 4 months saw more measles cases in the nation that over the entire year of 2006 (Grady, 2008).
Ø  When immunization rates drop, ‘herd immunity’ is threatened. Herd Immunity occurs when the majority of the population has been vaccinated, and the result of that, is that the unvaccinated population is safe as well because of the lack of people available to infect them (Iannelli, 2008).
Ø  “Actress Holly Robinson Peete recalls, "When my son was two-and-a-half, he was just recovering from an ear infection and had been on antibiotics, therefore his immune system was suppressed. He had already missed several appointments for his vaccination so his pediatrician wanted to catch him up on all of them in the same day. Although I asked if he'd consider waiting or breaking up the cocktail, which contains three viruses, he laughed me out of the office and belittled me. I firmly believe that it took my son to a place of no return and his body could not handle it. He had a violent reaction with convulsions and then he stopped talking and slipped into a silence. He no longer said, 'Hi, Mommy,' he no longer responded to his name and he no longer made eye contact."
Ø  Jenny McCarthy, who has been outspoken in her criticism of vaccines, said in a Time interview, "If you ask a parent of an autistic child if they want the measles or the autism, we will stand in line for the f___ing measles."
Ø  "Those who question the benefit of mass immunisation are not all irrational non-believers. Most support vaccination but are concerned at - and question the necessity for - the large number of vaccines and the early ages at which these are given. Many have studied the research, only to find - as I have - contradiction and uncertainty. They deserve to be treated with respect and given the opportunity for an open and honest debate.” - Dr. Richard Halverson, letter to the British Medical Journal

Wakefield and his article:
Almost incredibly, the trigger for what would become a worldwide controversy was a single scientific research paper published in a medical journal - the Lancet - in February 1998. Written by a then-41-year-old laboratory researcher, Dr Andrew Wakefield, and co-authored by a dozen other doctors, it reported on the cases of 12 anonymous children with developmental disorders, who were admitted to a paediatric bowel unit at the Royal Free hospital in Hampstead, north London, between July 1996 and February 1997.
Backed by a press conference and a video news-release, the five-page paper’s claims received huge media attention, and were followed by a sustained attack on the vaccine. This included further publications by Wakefield, criticising MMR, and led to an unprecedented collapse in public confidence in the shot, which, since the late 1980s in the UK and the early 1970s in the US, has been given almost universally to children, soon after they are one year old, almost eradicating measles and rubella.
The prime cause of the alarm was findings in the paper claiming that the parents of two thirds of the 12 children blamed MMR for the sudden onset of what was described as a combination of both an inflammatory bowel disease and what Wakefield called "regressive autism", in which language and basic skills were said to have been lost. Most disturbingly, the first behavioural symptoms were reported to have appeared within only 14 days of the shot.
Although the research involved only a dozen children, and its results have never been replicated, many medical breakthroughs have begun with small-scale observations, and, if true, Wakefield's findings might have been the first snapshot of a hidden epidemic of devastating injuries. "It's a moral issue for me," he said at the 1998 press conference, where he called for a boycott of the triple MMR, in favour of breaking it up into single shots, to be given at yearly intervals. "I can't support the continued use of these three vaccines, given in combination, until this issue has been resolved."
As the doctor campaigned, UK vaccination rates slumped: below the level needed to keep measles at bay. Even Tony Blair became embroiled in the controversy when Wakefield supporters suggested - the Blairs say wrongly - that the prime minister’s youngest son was not vaccinated with MMR. Meanwhile in America, a ferocious anti-vaccine movement took off, after Wakefield appeared on the CBS network's 60 Minutes programme in November 2000, speaking of an "epidemic of autism". This was followed by claims that all vaccines are suspect: either due to their content, or because of an increase in the number given to children.
(Taken from http://briandeer.com/mmr/lancet-summary.htm)
The Science:
o   “A Population-Based Study of Measles, Mumps and Rubella Vaccination and Autism” involved a retrospective study on Danish Children born between 1991 and 1998. It examined the incidence of autism spectrum disorders in the unvaccinated group of children during these 7 years, and compared it to the incidence of vaccinated children. The study concluded that evidence indicated a lack of association between the MMR vaccine and autism (Madsen et al., 2002).

o   CDC funded this follow-up study in Italy that compared neuropsychological outcomes of children at ages 10-12 years who were randomly assigned to receive one of two forms of diphtheria-tetanus-acellular pertussis vaccine (DTaP) in the first year of life, one containing thimerosal and the other containing 2-phenoxyethanol. As a result, children who received the thimerosal-containing DTaP vaccines had a higher cumulative exposure to thimerosal from all vaccines (137.5 micrograms of ethylmercury) in their first year compared with children who received the other form of DTaP (62.5 micrograms of ethylmercury) during the same age range. Ten years after vaccination, the two groups were tested on 24 neuropsychological outcomes. The overall results of the study do not support neurological or developmental harm to children resulting from thimerosal exposure. This strong study adds to the body of scientific evidence that thimerosal in vaccines is not harmful to children. The results are published in Pediatrics (2009 Feb:123(2): 475-482).

o   The National Institute of Child Health and Human Development (NICHD) and CDC collaborated on this study of regression in autism focusing on a possible association between the onset of autism in regression cases and measles-mumps-rubella (MMR) vaccination. This case-control study was performed by Collaborative Programs of Excellence in Autism sites utilizing screening data from 351 children with ASD (both with and without regression) and 31 typically developing children to describe the children’s early acquisition and loss of social-communication milestones. The study provided no evidence of an association between regression in ASD and MMR vaccination. The results of the study were published in the Journal of Autism and Developmental Disorders (2006 Apr;36(3):299-316).

o   An interesting example following the proposed link between MMR vaccination and autism was the decision of Japan in 1993, to stop the use of the three-in-one MMR vaccine, and instead, give them separately (BBC, 2002). A study published in 2005 examined the evidence in terms of autism rates that resulted from this decision. Despite the fact that no child received the MMR vaccine after 1993 in Japan, the incidence of autism actually rose (Honda et al., 2005).

o   It is important to recognize that MMR is administered within the first few years of life; coincidentally the same time during which many children are first diagnosed with autism (“A Look at What Causes, and Doesn't Cause, Autism."- CHOP).

• From the CDC Recent estimates from CDC's Autism Developmental Disabilities Monitoring networkfound that about 1 in 150 children have ASD. This estimate is higher than estimates from the early 1990s. Some people believe increased exposure to thimerosal (from the addition of important new vaccines recommended for children) explains the higher prevalence in recent years. However, evidence from several studies examining trends in vaccine use and changes in autism frequency does not support such an association. Furthermore, a scientific review
   by the Institute of Medicine (IOM) concluded that "the evidence favors rejection of a causal relationship between thimerosal-containing vaccines an autism." CDC supports the IOM conclusion.

• Frontline: the vaccine war (18:19-19:08) The risks of vaccines

In recent news: 
FEB 2nd 2010: Lancet retracts Wakefields paper: saying it was scientifically flawed. Organizations such as Generation rescue came out in strong force in support of both Wakefield and his science.
Brian Deer exposes Andrew Wakefield as a fraud: Rather, Wakefield had been payrolled to create evidence against the shot, and, while planning extraordinary business schemes, meant to profit from the scare, he had changed and misreported data on the anonymous children to rig the results published in the journal.

Relevant/Interesting Links:

• Lancet retraction: http://www.npr.org/blogs/health/2010/02/lancet_wakefield_autism_mmr_au.html
• Jenny McCarthy’s  website: http://www.generationrescue.org/vaccines/vaccines
• State Vaccine requirements: http://www.nvic.org/Vaccine-Laws/state-vaccine-requirements.aspx
• “Treatments” for autism: http://www.generationrescue.org/recovery/biomedical
• Studies that have been done investigating the issue: http://www.cdc.gov/vaccinesafety/00_pdf/VSD_Chart_of_Autism_Studies-Updated_Aug_18_09.pdf
• Vaccination Schedule age 0-6: http://www.cdc.gov/vaccines/recs/schedules/downloads/child/2010/10_0-6yrs-schedule-pr.pdf
• Vaccination Schedule age 7-18: http://www.cdc.gov/vaccines/recs/schedules/downloads/child/2010/10_7-18yrs-schedule-pr.pdf
• Brian Deer on The Lancet scandal http://briandeer.com/mmr-lancet.htm

Summary of class discussion (kwarlizzie)

Annie started the discussion by pointing to a few articles of interest which she had posted unto the page she created for the discussion.
She showed a video of a woman who lived in a community that had a rather high non-vaccination rate, and a video of a pediatric intensivist talking about incidences of vaccine-preventable diseases she had seen over the course of her career. This led to a discussion of whether or not the woman’s (non-vaccination)stance was the right one, or whether it was even a wise one.  The general consensus seemed to be ‘no’, because vaccines are meant to be protective: the absence of incidence of disease does not mean the absence of disease-causing agents. However, Professor Grobstein noted that as mortality and morbidity for diseases reduces (as a result of vaccinations), the more serious adverse reactions from vaccinations appear to be. He also noted that, we do not know ALL the possible adverse reactions that vaccinations can cause.
The discussion moved in a different trajectory after that. We moved from questioning the wisdom of the decision not to vaccinate to the legitimacy of the decision. Naa Kwarley and Sarah seemed to be of the definite opinion that it was not a legitimate decision at all, considering that the initial study that started the fracas, a study by one Dr. James Wakefield, has since been shown to be dubious: the conclusions from the study are shady, the subject size was very small, and Dr. Wakefield has had been receiving money from dubious sources.
Hope remarked that perhaps parents who choose not to vaccinate their children are acting legitimately, because they are making their decisions out of a series of observations that they have perceived.
It seemed that the discussion ended without consensus; rather it ended with the reminder that there really is method to the madness, that the choices of whether or not to vaccinate children are taken, usually after careful consideration and observation of some sort of data, and thus, either choice cannot be dismissed lightly.
Continuing conversation in on-line forum below
Conversation and implications to date (25 September 2010, adowton)
Maybe the key here is to stop arguing about authoritativeness and what bestows it and get back to making the best decisions one can in individual cases using all relevant observations to date and accepting that decisions always have to be made in the face of some uncertainty. (Grobstein)
i think its not always good to place the opinions of doctors or accepted science over personal observation….it makes sense to me for parents, and people in general, to question their doctors. (Hope)
I don't think that parents who worry about the risks of vaccinations should be disregarded as ignorant.  But, also I think that people should trust their doctors to make the right choices for them in regards to vaccinations for children at minimum.  (Kendra)
I believe that my parents are scientifically literate enough to make an educated decision, and that decision was to follow the recommendation of a well-respected doctor who has a greater degree of scientific literacy, and therefore is more likely to make the correct decision, based on that knowledge.  (smaley)
Sometimes personal beliefs have to be overridden for the greater good. (Colette) There shouldn't be a divide between uneducated and educated observations -everyone can make observations….To me, scientists who believe that there is no possible way that vaccines can cause autism in individual cases may be as narrow minded and dogmatic as parents who believe that vaccines are the only possible way that their child developed autism. (lbonnell)
While I do feel that this rejection of vaccines for fear of the unknown seems slightly irrational, debilitating and detrimental to herd immunity, I have a hard time justifying making a vaccine mandatory regardless of philosophical or religious beliefs. While the incidence of these infections remains relatively low in our country, I think it is reasonable for parents to have the choice to vaccinate their child. (dfishervan)

• Parents/persons who are a part of the anti-vaccine movement should not be disregarded as uneducated by the scientific community/community at   large for making sensible conclusions based on observations
• Vaccine literacy should be promoted to all: How they work, why we have them, what would happen if we didn’t have them etc. With increased knowledge/understanding, perhaps there would be less conflict.
• The scientific community should aim to be less authoritative and more in pursuit of transmitting information/observations
• Despite the many epidemiological studies done to refute a connection between vaccination and autism, no one can prove that in any given individual, that won’t be one of the adverse side-effects.
• Potential consequences of both vaccinating, and not vaccinating, should be examined by  parents whose children are vaccination age, the doctors of these children, and health care officials who write the vaccine schedule.