Conspiracy theories are nothing new, and it's not surprising many have sprung up around COVID-19.
Julie Leask is a professor in the Susan Wakil School of Nursing and Midwifery at the University of Sydney. She has spent decades studying how people approach vaccination, why those who oppose it do, and how to communicate with anti-vaxxers.
Recently, she has found that the COVID-19 pandemic has resulted in an environment that's ripe for conspiracy theories around vaccines to spread - as people have had their lives upended and are spending more time at home, with more time on the internet.
"We have what I call 'causal hunger'. We want to understand what's going on, why we've got this massive pandemic, why that virus became one that transmits from human to human," she said.
"It's understandable that people would be looking for answers and things that give them certainty in a time that feels very uncertain."
According to Leask, understanding the environment in which a conspiracy theory takes hold is vital for understanding them.
"The people who are attracted to these ideas are often people who like to see themselves as on the edge, highly critical of the mainstream, not wanting to follow like sheep the mainstream ideas," she said.
The subtext around vaccination had been going on since vaccines began, Leask said - the idea that there is "a conspiracy between the modern medicine industry and government to hide these so-called facts".
These suspicions had led to the advent of anti-vaccination activists, who Leask said presented themselves as "brave whistle-blowers, who are willing to break rank at great personal and professional cost to put their claims forward".
One such example was Judy Mikovits, a former biochemistry research scientist turned anti-vaccination activist. Her recently released video Plandemic - centered around conspiracies about the COVID-19 pandemic - spread virally on social media, before being removed for misinformation by various platforms like Facebook, YouTube and Twitter.
"The problem is that they usually take what I call a homeopathic dose of truth and then litter it with a kind of smoke and mirrors exercise that makes vaccines look terribly dangerous," Leask said.
One argument often touted by anti-vaccination activists was around the package insert included with vaccines, which lists all the potential side effects - some of which are serious.
Leask said these side effects came from mandatory randomised trials, where every outcome must be recorded - but this did not necessarily mean the outcome was linked to the vaccine.
"They have to list all these things in the package inserts, they haven't proven that the vaccine caused it, it's just a regulatory requirement.
"When I'm looking at what the safety profile of a vaccine is, I will be going to a reputable organisation that have made sense of the evidence of whether there's a causal link between the vaccine and that particular outcome."
However, she said there was a difference between the hardcore anti-vaccination activists encountered online and parents who were hesitant about vaccinating their children.
When engaging with people who were suspicious of vaccines, Leask said it was important to pick your battles, as some people were very fixed in their views.
"How you go into battle with them is really important, how governments go into battle with them is really important," she said. "What you don't want to do is give them a whole lot of oxygen and attention that might draw more attention to them than they might otherwise have gotten."
She said that while there actually weren't a lot of people who didn't vaccinate - usually around 2 percent in most societies - most of those who didn't were usually fairly quiet about it due to the reactions and labels given by others.
"Often people who are opposed to vaccination want their stories to be heard, they want to be treated like human beings and they don't want to be sort of stereotyped and stigmatised."
There were a range of factors around why people didn't vaccinate, she said, from believing what they read online, to negative experiences with the healthcare system or practical issues that prevented them from receiving vaccines on time.
Leask said she thought there was more of a focus globally on anti-vaccination activist than there needed to be - and the everyday vaccine hesitant parents were more important to address.
While she supported requirements around vaccines, Leask said she still had issues with the idea of mandatory vaccination with no exemptions.
"Governments will often see mandatory vaccination - 'just make them do it' - as a panacea for all the complex issues they have with their vaccine programs," she said.
"But it is not a quick fix and it should only be considered as an absolute last resort, when you have exhausted all your other options of making sure you have well-oiled systems, healthcare providers who are trained well and recommending vaccination, making vaccines easy to access and so-forth.
"Then you might consider a requirement that has exemptions that are hard to reach and only is there for the really hardcore non-believers."