Understanding the psychology of vaccination

Vaccination is the hot topic of 2021, as the world looks to escape the grip of COVID-19 and its various tentacle-like strains. Unfortunately, it’s been a rocky road thus far, not the least because of vaccine supply issues but also due to somewhat of a drug image problem.

I’m sure we’d like to think that we are generally rational people and that we make the best decisions based on the wealth of information provided to us. In reality, the way we often make our resolutions is biased and based on incomplete information.

The framing of vaccine efficacy

Imagine if I told you that there were 2 vaccines available to you:

1. Vaccine A— COVID-19 showed no symptoms in 82% of people who chose this medicine
2. Vaccine B — 1 in 5 people who have received this jab still suffered from COVID-19

Which vaccine would you choose?

My guess is that you probably went for Vaccine A, right?

A recent report by AstraZeneca stated that with two doses and a 12-week intermediate period, the drug had been 82% effective against the virus.

In the example above, both vaccines are the same — they are AstraZeneca. The reason that vaccine A looks more attractive is because I have framed its efficacy in a positive light, while for B I have focused on its inefficacy. Taking advantage of language and framing is a common technique used by people trying to influence others. You will see it all of the time in the media and from politicians. Next time you’re being presented with statistics in either a positive or negative frame, try flipping the frame and seeing if you still hold the same opinion. E.g. 9 out 10 politicians are honest vs. 10% of all politicians are corrupt (I made up this statistic).

Blood clots and the availability bias

Now let’s look into those nasty blood clots!

At last count there have been 2 deaths from the rare condition of ‘thrombosis with thrombocytopenia syndrome’ (TTS), which is specific to people who have received the AstraZeneca vaccine.

Blood clotting itself is actually a common cause of death in Australia, causing 10% of hospitalised deaths. Without making light of any loss of life, two deaths is a miniscule 0.2% of the 910 COVID-19 attributable deaths in Australia. So if vaccines have potential to save many lives and open up the world again, why is 0.2% chance of death from blood clotting holding people back?

The answer is the same reason that anti-vax has become a thing — availability bias.

As I wrote in November last year, the availability bias is where humans rely on the information that is most accessible to us. If we are bombarded by news reports of another case of blood clotting, we automatically think that the importance the media has given to this story reflects the relative size of the problem. It doesn’t, and sensationalist reporting can actually do major harm in the community. Similarly, articles showing the protests and exploits of a handful of anti-vaxxers may influence people to think that this minority is larger than it actually is.

If you are worried about blood clotting, and this is stopping you from being vaccinated, please speak to an expert and don’t just take that YouTube influencer’s word for it.

How ideas spread

Momentum is a powerful thing in spreading a message and its somewhat ironic that the misinformation about vaccines often spreads just like the viruses they are trying to protect us from. In Malcolm Gladwell’s influential book, The Tipping Point, he discusses the three rules that cause ideas to spread throughout a community.

1. The Law of the Few — where influential people play a big role in spreading the message
2. The Stickiness Factor — the memorability of the message
3. The Power of Context — what has happened recently can greatly assist the spread

One of the main reasons why the concept of anti-vaccination became a thing, is that influential people spread their opinions using personal stories, which were both emotional and memorable. A good story is always much more powerful than a bunch efficacy statistics buried within a research paper.

A study of the human psyche

Events that only occur once in a lifetime are fascinating studies into social psychology and the ways humans respond to adverse situations. While such a serious pandemic will hopefully only happen to us once, there will be countless other challenges we may face throughout our days — wars, natural disasters, alien encounters, who knows? This means that while no two disasters are alike, there is much we can learn and transfer to future situations that we meet. Hopefully we’re lucid and smart enough to apply these lessons when future trials inevitably come around.