Marketplace sifted through mountains of studies and arguments, examined anti-vaccination documentaries and even attended an anti-vaxx rally in Washington, D.C., to get a deep sense of the information being distributed.
We also spoke with more than a dozen vaccine-hesitant and anti-vaxx Canadians, and heard from many more via email.
Many arguments and scientific studies seemed reasonable, so we ran them by specialists in that particular type of science or medicine.
We consulted with toxicologists, vaccinologists, microbiologists, psychologists and academics throughout this investigation, all of whom confirmed the safety and efficacy of vaccines.
Here are some of the most pervasive concerns Canadians brought to Marketplace, and why experts say we shouldn't worry about them:
It’s true that vaccines contain chemicals that would be considered toxic at very high doses. But so does pretty much everything humans interact with daily. Even water is toxic to humans in high enough quantities.
Although the idea of a "chemical" may sound harmful, everything we eat can be broken down into its chemical makeup. For example, here is a list of all the chemicals that make up an all-natural banana:
The vaccine ingredients that most people are concerned about — mercury, formaldehyde and aluminum — exist only in very small, non-toxic quantities.
Mercury was previously used as a preservative in some vaccines in the form of thimerosal. It was one of the first ingredients that parents took issue with, and there was so much public concern that it was removed from almost all vaccines, despite the fact that it never existed in quantities that would be considered problematic.
Vaccines only ever contained 50 micrograms of thimerosal (equal to 25 milligrams of mercury) per 0.5 millilitre dose. For comparison, that's about the same amount of elemental mercury in a three-ounce can of tuna. Nowadays, mercury only exists in certain types of flu shots.
Formaldehyde is another ingredient often of concern. There is only between 0.1 mg and 0.003 mg of formaldehyde in a single dose, depending on the vaccine. Compare that to a 200-gram pear, which contains 12 mg of formaldehyde, or 120 times as much. Formaldehyde is actually a chemical that your body creates itself as part of the metabolic process.
Aluminum is another ingredient people are concerned about. It is also found in very low quantities in vaccines for diseases like HPV and hepatitis. Aluminum is one of the most common metals found in nature and is present in air, food and water and breast milk. The reason it is added to vaccines is because it helps create the immune response needed to develop immunity.
Vaccines work by injecting a dead, weakened or partial version of the virus into the body so the immune system can learn what it looks like and how to fight it the next time it is encountered — before it gets deep within the body and causes physical harm.
Adjuvants, like aluminum, make that dead virus look more threatening than it is in order to activate an immune response, prompting the body to learn how to fight the disease instead of immediately flushing it out.
It is important to note that all traces of aluminum (and the rest of the ingredients in the vaccine) would still be flushed completely out of the body within a day or two, leaving behind only the lessons learned by your immune cells. The ingredients don't build up in the body, therefore, receiving many vaccines will not stack up the levels of aluminum or other ingredients.
Learn more about aluminum and other adjuvants here.
Vaccines and autism
The claim that links vaccines and autism originates from a now-discredited 1998 study published in the prestigious Lancet medical journal by former gastroenterologist Andrew Wakefield an, titled "Ileal-lymphoid-nodular hyperplasia, non-specific colitis and pervasive developmental disorder in children."
There were 13 authors listed on the study, with Wakefield being the lead author. But in 2004, 10 authors retracted the interpretation of the study after "serious allegations of research misconduct" were brought to the attention of The Lancet, including allegations of biased selection of patients and unethical, invasive procedures.
The journal also found Wakefield had unreported conflicts of interest, namely that some of the research was funded by lawyers who were acting on behalf of parents suing vaccine manufacturers. Two authors did not retract the interpretation (including Wakefield) and one could not be contacted. As a result, Wakefield lost his medical licence.
Many studies have since been done to test his hypothesis, but all scientifically reputable studies found no link. A 900-page analysis by the American Institute of Medicine (IOM) looked at all relevant studies and meta-analysis, finding that "the mechanistic evidence regarding an association between MMR vaccine and autism is lacking."
This may sound like the science is simply insufficient, however we checked the language with experts like microbiologist Jocelyn Sringly, who explains that the phrase "lacking" in science is the category below "weak," meaning they found zero evidence.
The biggest and most recent study looking for a correlation between vaccines and autism followed 657,461 children born in Denmark from 1999 through 2013. This study compared MMR-vaccinated with unvaccinated children and found "no increased risk for autism." This study even looked at sub-factors, like sibling history of autism, autism risk factors or other childhood vaccinations to see if those factors could combine with a vaccine to create a higher risk. But again, it found no increased risk.
Big pharma and money
Big Pharma is a wealthy industry that has behaved unethically in the past — and particularly has come under fire in recent years due to the opioid crisis.
But vaccines are not big money-makers compared to other drugs.
Only two to three per cent of the global pharmaceutical profits come from vaccines, despite the fact that most people on earth are vaccinated. In fact, most childhood vaccines have expired patents, and it's estimated that once a generic drug enters the market after a patent expiration, name-brand sales drop by 80 per cent.
Physician offices often lose money on the administration of vaccines and some governments have to incentivise drug companies to keep making them because of the fact that the profit margins are so low.
Vaccines take lots of time and money to develop because the regulatory standards are higher than other drugs since they are being injected into healthy people. They may make some money in the first few years, but they also have to carry the burden of cost for all the years of research and development.
Vaccines prevent millions of people from getting seriously sick every year. If you're worried about motives, keep in mind that Big Pharma makes a lot more money off people that are sick than people that vaccines have kept healthy.
Prevalence and danger of vaccine preventable disease
Even though we don't see much of some diseases anymore, like pertussis and polio, they are only kept at bay because of the vast majority of the population being vaccinated.
If you talk to older generations, they'll tell you stories of their friends who became deaf, blind, disabled or died from many of the diseases that vaccines have eliminated in North America.
In areas where vaccination rates drop past a certain threshold, we can see resurgence of these diseases, which can be picked up and brought back to countries that have "eliminated" status.
For example, Samoa had a significant drop in vaccination rates over the past few years due in part to anti-vaccination campaigns, and an MMR scare after a nurse accidentally mixed up two shots with an expired anesthetic, resulting in two deaths. When measles made it into the community, it quickly infected thousands of people; 81 of those infected died, and almost all of them were babies and young children.
Authorities arrested an anti-vaxxer for spreading misinformation during the epidemic while the government was frantically trying to get everyone vaccinated.
The only disease that has been entirely eradicated worldwide is smallpox. This was due to a very effective mass-vaccination initiative in the 1960s which managed to drive the disease into complete extinction. Polio is a hopeful candidate for eradication, with only three endemic countries left.
Until complete eradication is reached, vaccination is still necessary for highly contagious and dangerous diseases. Measles can live for two hours in airspace, which means if an unvaccinated person entered a room where someone with measles coughed an hour earlier, they would still be likely to catch the virus.
Here is a link to the largest, most comprehensive and most recent study discrediting any notion that there is a link between vaccines and autism https://annals.org/aim/fullarticle/2727726/measles-mumps-rubella-vaccination-autism-nationwide-cohort-study
Here is the full report by the institute of medicine (IOM) Adverse effects of Vaccines: Evidence and Causality: https://vaccine-safety-training.org/tl_files/vs/pdf/13164.pdf
Here is a list of some additional reliable, scientific sources curated by Natasha Crowcroft, Director of the Centre for Vaccine Preventable Diseases; Professor at the Dalla Lana School of Public Health and Laboratory Medicine and Pathobiology; and Adjunct Scientist ICES and Senior Fellow Massey College at the University of Toronto.
On worldwide efforts to curb vaccine misinformation:
On worldwide efforts to curb vaccine misinformation:
We don't agree Polio vaccine dosent give Autism.
Post Polio Litaff, Association A.C _APPLAC Mexico