Vaccine hysteria

From RationalWiki

Fears about vaccines were excusable when they were new, but are the present concerns grounded in anything?

Vaccine hysteria is a trend of mistrust of vaccination that is almost as old as the technique itself. Anti-vaccination proponents blame vaccines or their ingredients for a range of maladies (often childhood illnesses) whose mechanisms are not currently fully understood. The ubiquity of vaccination often makes them an easy target for blame.

Vaccine-preventable disease has been a major cause of illness, death, and disability throughout human history. The advent of the modern vaccine era has changed this significantly. In fact, most North Americans and Europeans have little memory of the pre-vaccine era, where diseases such as mumps and measles were very common. In more recent times, there has been much debate in the press and in the doctor's office regarding vaccine safety - namely what possible side-effect vaccines cause and whether these outweigh the risks of leaving a population without a vaccination program. Vaccines have been alleged to cause all manner of illnesses; autism is a prominent example, as its direct causes are still fairly mysterious and probably very wide-ranging, with no single cause or lifestyle risk-factor being identified. Some very prominent Americans have spoken out vociferously about the supposed danger of vaccines.^[1]

[edit] Premise

There are many beliefs, not supported by any accepted scientific evidence, that vaccines are inherently harmful. It is claimed that specific vaccines, such as MMR or specific ingredients like Thiomersal are causative factors leading to disease. Some claims are more vague, based on the feeling that vaccines are "unnatural", that they are somehow "useless", or that the diseases they prevent "aren't that bad anyway". There are, of course, well developed published data on the complication rates of vaccines and this data plays an essential role of the approval process vaccines must pass in order to be licensed for sale, and recommended for use.^[2] When faced with this, anti-vaccination activists often argue that the reporting system is not robust enough, resulting in these figures being misleading. The reality is that unexpected side-effects can occur, just as a parachute may fail to open, but the regulatory process ensures that such events are rare.

This particular pseudoscientific belief is unlikely to go away soon, despite the evidence attesting to the efficacy and safety of vaccines. It has several important factors that make it a very durable belief.

1. It involves harm to children
2. It involves science that most people do not understand
3. It is frightening
4. It seems on its face to "make sense", especially to make sense of an otherwise unexplainable tragedy

For vaccination recommendations by governments or advisory institutions, for example the World Heath Organisation (WHO), to change to an anti-vaccination stance, it must be fully demonstrated that the harms caused directly by the vaccine are greater than the harms caused by witholding the vaccine from circulation. This needs to be demonstrated at a population level, with solid and significant statistics.

[edit] Disease impact in pre-vaccine era

Adverse reactions to the HPV vaccine Ceravix, reported between April 2008 and 23 September 2009: very few, and fairly mild.

To put it simply: complications are more likely to arise from illness than from vaccination.

The current impact of vaccines on health is very simply stated here. Children who get measles have a 1 in 20 chance of developing a serious complication; however, serious complications from the vaccine number 1 or 2 per million, according to the Institute for Vaccine Safety at Johns Hopkins University.^[3] Before the introduction of measles vaccination, there were about half a million cases per year in the United States. Only 89 cases were diagnosed in 1998.^[4] Historically, the mortality rate for measles in the U.S. was about 1 to 3 deaths per every 1000 cases, with young children suffering the highest mortality rates.^[5] Most deaths occur as a result of pneumonia or encephalitis.^[6]

After the introduction of polio vaccination, cases in the United States decreased from almost 30,000 in 1955--many of which produced paralysis or death—-to 910 cases by 1962. New cases of polio in the U.S. are now a thing of the past.^[7] Of the two types of polio vaccine, the oral vaccine, while effective, is the less safe of the two. Since there are no more naturally acquired cases in the U.S., the oral vaccine had become the only cause of polio (8-9 cases). Since the vaccine risk, however small, eventually exceeded the disease risk, the oral vaccine was abandoned in favor of the killed vaccine. In regions where polio is still a major problem, the oral vaccine is still a better choice, as it can enter the water supply and vaccinate others passively. In regions with high HIV rates, this may be less true, as live vaccines are usually avoided in immunocompromised patients.

In Britain, there was concern in the early 70s about the pertussis vaccine. It was blamed for several cases of encephalitis. The connection was never proved, and vaccination rates dropped from 77% to 39%. Following this drop in immunization, the UK was hit by two large whooping cough epidemics, one in 1978, and one in 1982, both of which resulted in many deaths.^[8]

The rates of complication from vaccines are so low that the benefit of vaccines for each individual child is higher than the risk of a poor outcome, so it is not true that the few children with adverse events are being sacrificed for the health of others. For example, the CDC compiles rates of risk from disease vs. risk from vaccination.^[9] For the MMR (measles, mumps, rubella) vaccine, these are the data:

Measles Complication Rates:

Per case of measles.

• Pneumonia: 6 in 100
• Encephalitis: 1 in 1,000
• Death: 2 in 1,000
• Congenital Rubella Syndrome: 1 in 4 (if woman becomes infected early in pregnancy)

MMR Complication Rates:

Per injection given.

• Encephalitis or severe allergic reaction: 1 in 1,000,000

[edit] Negative effects of currently used vaccines

Most commonly used vaccines have a risk of severe complications that is so low that it is impossible to tell statistically whether or not the vaccine played a role in causing these problems. Certain less commonly used vaccines are known to have greater dangers. For instance, the smallpox vaccine, which is not in wide use, has a well-quantified complication rate. Given the fact that the risk of disease exposure is almost zero - due to the success of the vaccination program - it is not worth the risk to vaccinate the population at large any more.

[edit] Specific concerns

[edit] Thiomersal (also known as thimerosal)

Molecular structure of thiomersal, the Hg is the dreaded mercury atom that causes most of the controversy.

Thiomersal is a mercury-containing compound used as a preservative in many vaccines. The fact that some mercury compounds are toxic has led many to conclude that vaccines containing this compound are dangerous. Many mercury compounds - particularly those with mercury-carbon bonds - are neurotoxins, such as dimethylmercury.^[10] While in large doses thiomersal can be toxic, a 2002 study indicated that the mercury levels in infants receiving a vaccine preserved by an appropriate amount of thiomersal were low; some were so low that they could not be measured. The blood concentrations of mercury were below the EPA guidelines. The amount of mercury in stool samples was higher than normal, although this is an indicator that the body was eliminating the thiomersal, rather than accumulating it.^[11][12] Most of the concern about thiomersal derives from analogy with methylmercury, a well characterized mercury compound, but it is unclear whether the actual pharmacology is similar to thiomersal - after all, ethanol and methanol are extremely similar molecules but have quite different effects on the body. Initial studies on the pharmacokinetics indicate several differences between methylmercury and thiomersal.^[13] The amount of thimerosal actually present in vaccines is quite low and, most importantly, there are large studies available that have shown no evidence of harm.^[14]

[edit] Multiple Sclerosis

Concern has been raised about a connection between MS and vaccines, especially the Hepatitis B vaccine. One of the several studies done on the topic showed a potential link^[15], but there were methodologic problems^[16], and most other studies failed to show a link.^[17][18] The most recent CDC publication on the matter cites fifteen different studies showing no link between MS and the Hepatitis B vaccine.^[19]

[edit] SIDS

The DPaT has been suspected of causing Sudden Infant Death Syndrome that causes children to stop breathing and die.^[20] However, studies have not shown a connection between SIDS and DPT/DPaT vaccinations.^[21] Recent studies have identified abnormalities in the development and function of medullary serotonin (5-HT) pathways in the postmortem brain from sudden infant death syndrome (SIDS) cases, suggesting 5-HT-mediated dysregulation of the autonomic nervous system in SIDS.^[22][23] This is basically stating that SIDS has a strong genetic component and is more prevalent in families that have issues with serotonin reuptake, thus preventing the infant from shifting when their airway becomes blocked while asleep.

Research into SIDS is progressing, and has left behind the fictional link to vaccines.

[edit] Autism

There has been much concern about a possible link between autism and vaccines, particularly the MMR - measles, mumps and rubella - vaccine in the UK and thimerosal, a preservative found in some flu vaccines.^[24] Part of this concern is due to a possible rise in cases of diagnosed autism over the last few decades - much of it raised by parents of autistic children, and by prominent Americans such as Jenny McCarthy. More often than not, evidence given by those peddling a link is indirect and anecdotal. When such groups do attempt to be scientific, they primarily cite links between ethylmercury exposure and other neurologic problems outside the setting of vaccine administration. For instance, according to one source "In 1977, a Russian study found that adults exposed to much lower concentrations of ethylmercury than those given to American children still suffered brain damage years later".^[25]

The following, un-cited statement gives anecdotal evidence of a link between ethylmercury and "brain damage". It is hard to evaluate without a citation, but the overwhelming evidence from the medical literature is clear. This statement works to increase levels of fear, but makes no mention of actual vaccines or actual patients. It certainly doesn't mention statistics. From the same article:

Several very well done population-based studies have been conducted into the link between autism and vaccinations, although they aren't widely reported as it is a known fact that hard facts do not resonate with the public conciousness as anecdotes and sob stories from concerned individuals and interest groups. These particular studies have looked at actual populations in actual real-life conditions, exposed to the actual substance in question; none have shown any connection between autism and the thimerosal preservative or the MMR vaccine. There is overwhelming evidence that the MMR and thimerosal-containing vaccines play no role in the development of autism.^{[26][27][28][29][30][31][32]}

A small study, published in The Lancet in 1998, became famous around 2000-2002 when the UK media caught hold of it. It propositioned an alleged link between the measles vaccine and autism despite a small sample size of only 12 children. This eventually lead to what Guardian columnist and science writer Ben Goldacre described as "the media's MMR hoax" ^[33] - in reference to the evidence in favour of a link being so lacking that it may as well be described as a hoax. The paper was partially retracted several years later but continued to be the most often cited case study for the link, despite mounting evidence (including one large study into the rates of autism in adults who wouldn't have received MMR). It was finally considered "thrown out" by the media on February 2, 2010, after it was discovered that the author of the study, Andrew Wakefield, behaved unethically. Specifically, Wakefield was found guilty of not acting in the best medical interests of the children he did research on (one child was severely injured in a colonelcy), as well as not disclosing his previous involvements with anti-vaccination groups prior to the study and it hitting the news.^[34]

[edit] Shaken baby syndrome

A small group of people have tried to tie Shaken Baby Syndrome to childhood vaccinations. The "studies" that have been published are quite weak. Most are available only online from non-recognized sources, and are "based on personal experiences of the authors..."^[35] The rest of the "evidence" is based on personal testimonials of involved parents and physicians.^[36][37] These ideas are well-de-bunked here.

[edit] Intentionally tainted vaccines

A growing number of Muslims believe that Western pharmaceutical companies have intentionally tainted the polio vaccines used in their countries. They believe that Western powers secretly use the vaccines to spread AIDS and/or infertility among Muslims. Unfortunately, this wave of hysteria has led to a sharp decrease in polio vaccinations and an almost equally sharp increase in polio cases in Muslim countries.^[38] The Nigerian government further increased the hysteria by banning all polio vaccines in February, 2004.^[39] This isn't limited to the developing world; Eustace Mullins wrote an article claiming the polio vaccine was a Jewish plot to mass-poison American children.^[40]

[edit] In the news today

In the United States it is generally held, perhaps "legally held" is a better way to phrase it, that parents have the right to have their children not be inoculated if they, the parents, so desire. However as recently as today^[41][42] a parent was harassed by a bureaucrat for trying to exercise that right. America, the Land of the Free.

The H1N1 swine flu vaccine is a current hot topic among vaccine denialists, from fears the vaccine may be unsafe (stoked by reports of side effects from the old 1976 swine flu vaccine) to conspiracy theories that the new vaccine is a plot to curb overpopulation.^[43]

Safety concerns about the HPV vaccine Cervarix were raised after a girl died after being injected with the vaccine.^[44] The story was immediately jumped on by anti-vaccination groups and was widely reported in the general and scaremongering media. It was later determined that the death was due to an undiagnosed tumour but the same media that cried out for "more research" into the incident tended to bury this conclusion; undoubtedly a large part of the UK population still believe the young girl died due to a direct reaction to the vaccine. Anti-vaccination blogs and organsiations, of course, have cried conspiracy on this conclusion. The Sunday Express also hyped up fears about the jab by - one can only assume deliberately - misquoting Dr Diane Harper and claiming that the vaccine was "just as deadly as the cancer". Indeed, practically every single one of the claims, which were on the front page of the newspaper, were false; ranging from what Dr Harper actually said, to her actual level of involvement in the vaccine. In true tabloid style, the corrections were well and truly buried.^[45]

[edit] UK

Most recently, the MMR-autism link (mentioned above) hit the UK headlines after Andrew Wakefield, the lead author of a paper suggesting a link between autism and MMR, was found guilty of unethical conduct. Despite the ruling only applying to his ethical conduct in the research, which had been questioned for several years (a "conflict of interest" was raised in 2004, three years after he left the Royal Free Hospital in controversial circumstances), the UK media have taken the ruling to also mean "his work has been discredited".^[46] As those who may have seen Wakefield's original research would know, a series of 12 case studies never particularly had and credit to actually be discredited.^[47] Probably as a result of the excess publicity, The Lancet - the premier medical journal that featured the research - issued a full retraction of the study in February 2010.^[48]

[edit] Conclusions

Despite the hysteria and media coverage, there is no evidence linking currently popular vaccines and serious medical conditions. In fact, epidemiologic evidence shows that vaccines prevent a huge burden of disease and death in the world. Despite this, there is still a level of concern regarding vaccines. Public education about vaccines and health must continue, and we must continue to provide everyone with the rigorous scientific education needed so that they may better evaluate the facts themselves. If you still think that vaccines are "unsafe", then you may also want to think about many other things that unsafe, and reconsider ever doing them.

For an alternate view, without appropriate scientific citation, you can visit a number of sites, including The National Vaccine Information Center.

[edit] See also

Anti-vaccination proponents

• Jim Carrey
• Bill Maher
• Jenny McCarthy

Related topics:

• Flu shot
• Guillain-Barré syndrome
• Moral panic

[edit] External links

• Opposing Views' experts debate the link between autism and vaccines
• ‘This Question Has Been Asked And Answered’
• 'The Anti-Immunization Activists: A Pattern of Deception,' Ed Friedlander, MD

[edit] Footnotes