Growing up in the 90s, my parents, like many others, made the choice on my behalf to not receive the MMR (Measles, Mumps, and Rubella) vaccine, fearing it may cause autism.

A lot has changed in those twenty-something years.

Firstly, I’m now an adult making my own informed medical decisions and am up-to-date with my vaccinations. More importantly, the original research claiming a link between the MMR vaccine and autism is widely refuted and the lead scientist behind the research, Andrew Wakefield, was discredited and banned from practicing medicine.

Despite this, twenty years after the fraudulent paper that gave birth to the infamous autism/MMR myth, support for anti-vaccine movements is still unwavering.

So, what exactly is a vaccine?

Shots, jabs or jags – whatever you like to call vaccinations – are typically an injection of a cocktail of immune-priming substances that protect the body from a specific disease-causing agent (or pathogen), such as some bacteria and viruses.

The main ingredient that is used to train the immune system to intercept the pathogen belongs to the pathogen itself. The key is that the pathogen is adapted so it would be able to make your body respond to the threat without causing the disease itself. Nifty, right? This ingredient comes in one of four varieties: a small bit of the ‘bug’ (subunit vaccine), a small dose of the toxin it makes (toxoid vaccine), a ‘dead’ version (inactivated vaccine) or an extremely weakened version (live attenuated vaccine).

Other substances may be added to some vaccines including aluminium salts, lipids (a fat-like substance), proteins and sugars. These substances have one of the two roles:

1) Stabilise the vaccine so that it can be stored until needed, and still work.

2) Boost the immune response towards the vaccine (known as adjuvants).

Put all these ingredients together (plus 10+ years of rigorous testing) and you have a vaccine.

But how does it work? Vaccines train your immune system to recognise a pathogen before you have encountered it; similar to a scenario where you have seen a photograph of someone before meeting them in person. By training the immune system to recognise a pathogen through vaccination, it develops a faster reaction time to recognise and also destroy an invading pathogen when it comes head to head with the real deal.

If vaccines help us, why do some people choose not to get them?

Some people’s faith in medicine has faltered. In an age of instant information, it’s easy to get lost in the pool of knowledge out there regardless of whether it’s true or false. The blame cannot be pinned entirely on that one false study published twenty years ago. However, celebrity endorsements and the misleading 2016 ‘documentary’, Vaxxed, (incidentally directed, produced by, and starring the author of the fraudulent study) certainly doesn’t help matters.

Arguments from some anti-vaxxers (people against vaccinations) span from the mistrust of health officials and governing bodies, to safety concerns for vaccine components – though the two are not mutually exclusive. Here, I’ll focus on debunking the most common misconceptions surrounding vaccine safety.

‘Vaccines cause serious health problems e.g. Autism’:

I won’t dwell on this any longer, it is simply not true. Twenty years of extensive studies by scientists across the globe have discredited this claim ¹.

‘Vaccines contain dangerous substances such as formaldehyde and aluminium’:

Formaldehyde: While it is true that formaldehyde can be one way to inactivate or ‘kill’ the pathogen to prepare it for use in a vaccine, the vaccine itself contains only trace amounts of this chemical which is not enough to cause harm. In fact, the cells in our own body produce formaldehyde and the body is equipped to remove the tiny amounts that are introduced by vaccination ².

Aluminium. You might be thinking what is aluminium, a component of drinks cans and foil, doing in vaccines? Aluminium-based products, such as aluminium salts, are used as adjuvants to help boost the immune response of the recipient to the vaccine. This is very different to what goes into making drinks cans. Aluminium salts in vaccines are harmless and are present in very low quantities, even lower than what we encounter on a daily basis and can be found naturally occurring in soil, used in antiperspirants, and even in the food you eat ³.

All in all, vaccines are extensively tested before widespread human use. Though side effects may occur, they are better than the alternative of experiencing the disease in full. The bottom line is, vaccine components are safe.

How are unvaccinated children a risk to the general public?

‘It is my child and my choice, it doesn’t affect anybody else if I choose not to vaccinate my child’

I’ve seen similar statements plastered over the internet from members of the anti-vax community. These are most likely not isolated cases. It is not a matter of one or two unvaccinated individuals in a community, there are many. This is where the problem lies.

Unvaccinated people are at risk of contracting potentially lethal pathogens. Even if there is no disease progression, that person may act more efficiently as a ‘carrier’ of pathogens (that’s not to say that vaccinated people cannot also act as carriers of certain pathogens). However, the extra time that it would take for an unvaccinated individual to destroy an invading pathogen (if at all), increases the time that they can come into contact with another unvaccinated person or the general public and allow the pathogen to spread.

This is problematic as not everybody can be vaccinated, for instance, those who are too young or too old to be vaccinated, as well as people with weaker immune systems, such as cancer patients and those with immune-related disorders. If these vulnerable individuals come into contact with a pathogen, through interactions with carriers, the disease could be life-threatening.

Herd immunity can prevent this⁴. This is when there is a high enough percentage of vaccinated people who can protect the whole population by acting as a barrier to transmission of a pathogen. The higher the percentage of elective unvaccinated people, the increased risk of herd immunity failing and risk of pathogens spreading to vulnerable individuals. Recent measles outbreaks across Europe (including in the UK) and in pockets in the United States (21/50 States at the time of writing) are classic examples of places where herd immunity has failed due to lack of vaccine uptake ^{5 6}.

Higher percentages of unvaccinated people are not only a risk to the vulnerable but to the population as a whole by acting as a ‘reservoir’ of infection. A reservoir is a population where a pathogen can exist and spread without the transmission chain being cut off. The longer a pathogen ‘grows’ and spreads, the higher the chance that pathogen adapts to better suit its host through mutations. For pathogens such as viruses, this can be an extremely quick process. Eventually, these mutations could cause infections to spill over into vaccinated populations causing an outbreak – meaning everybody is at risk of developing the disease.

By having a certain number of people in the population reach the threshold to achieve herd immunity, we decrease the chances of such events occurring.

How do we increase vaccination uptake?

The Australian government has linked child care benefit payments to vaccinations since 1998. Over the years, their government has clamped down on conscientious objection to vaccination. The most recent action saw child tax benefit reductions change from an annual reduction to a fortnightly reduction – to serve as a vaccination reminder ⁷. In addition to ‘no jab, no pay’ legislature, unvaccinated children are being turned away from childcare facilities in a ‘no jab, no play’ movement.

Benefit cuts might not be the answer. Some reports claim there is a rise in affluent anti-vaxxers – therefore targeting these groups will require more than cuts to a benefit that they are unlikely to receive ⁸.

While government intervention to encourage vaccination seems like it might be the way forward, it may be hurting the situation in cases where mistrust in the government factors into objection to vaccination. In fact, some anti-vaxxers in South Australia have established their own social services with anti-vax friendly health practitioners in order to navigate current laws there.

One way to help increase the support and uptake of vaccinations is to improve how we communicate to people about them. This includes being transparent about their components, production and most importantly their public health benefits.

#VaccinesWork

Both the title of this article and a mantra of pro-vaccine tweeps (that is Twitter users, for those not immersed in the Twitter-verse), there is no denying that #VaccinesWork. The eradication of smallpox and the fact that my generation (in the UK) first learned of polio through textbooks and not in day-to-day life, is a testament to the power of vaccination. Sadly, there are cracks in the woodwork, with more reports of vaccine-preventable diseases appearing more frequently. So my parting message is this – run with the herd, because #VaccinesWork.

This article was specialist edited by Ricardo Sanchez and copy-edited by Lavanya Sundar.

1.  A commentary of one such study was published by The Guardian  https://www.theguardian.com/society/2015/apr/21/no-link-between-mmr-and-autism-major-study-concludes  
2. https://mrc.ukri.org/news/browse/toxic-formaldehyde-is-produced-inside-our-own-cells/
3. https://www.nhs.uk/conditions/vaccinations/vaccine-ingredients/
4. Dr Adam Kucharski explains the concept of herd immunity in this short video  https://www.youtube.com/watch?v=cEn1PKyBUNc
5. https://www.independent.co.uk/news/health/measles-outbreak-latest-symptoms-vaccination-england-infection-gps-europe-romania-a8428356.html
6. https://www.paho.org/hq/index.php?option=com_docman&task=doc_view&Itemid=270&gid=44091&lang=en
7. https://www.aph.gov.au/About_Parliament/Parliamentary_Departments/Parliamentary_Library/pubs/rp/BudgetReview201516/Vaccination
8. https://www.washingtonpost.com/opinions/rich-parents-get-away-with-not-vaccinating-their-children-poor-ones-dont/2017/05/10/2ccf6d58-3106-11e7-8674-437ddb6e813e_story.html?utm_term=.92c0aac72660