Transcript

MIC CAVAZZINI:               Welcome to Pomegranate Health, a podcast about the culture of Medicine. I’m Mic Cavazzini, for the Royal Australasian College of Physicians. In the last episode we heard how computational models have been used to make predictions about the spread of the novel coronavirus. There are many layers of public health intervention that can reduce the rate of transmission. Social distancing, mask wearing, lockdowns and vaccines each nudge the reproduction number down. But you need all of them working together to make a significant impact, and that means you need the community on board.

Later in the podcast we’ll hear an interview with Professor Allen Cheng who’s played this game harder than most. As Deputy Chief Health Officer of Victoria he advised on implementation of the lockdown that brought Melbourne’s second wave to a halt after four long months. If being part of fun police wasn’t enough responsibility, he also co-chaired the COVID-19 Panel at the Australian Technical Advisory Group on Immunisation which had to weigh up the suitability of the Astrazeneca vaccine as reports of rare side-effects and death were emerging in real time.

But first let’s hear a presentation by Jessica Kaufman, a research fellow in the Vaccine Acceptance, Uptake and Policy Research Team at the Murdoch Children's Research Institute. Her work uses mixed methods to evaluate effectiveness of public health messaging across the diverse community. She delivered this talk alongside Allen Cheng at the RACP Congress in May. At that time there was virtually no community transmission of SARS-CoV-2, so the communication strategy around vaccines had different challenges. But Jess Kaufman very clearly maps out the fundamentals in this important space.

JESSICA KAUFMAN:        So, I guess, you know, we’re presenting the very challenging policy options that had to be decided based on epidemiological modelling but the public really need to understand and accept, and trust and then adhere to those restrictions to actually control the pandemic. So, the real where the rubber meets the road, so to speak, is in the communication of these complex decisions that are based on this modelling. And effective communication in this context really relies on a range of factors, including the clarity, transparency, consistency, accessibility and the credibility of that communication.

So, clarity and transparency are related, but they’re not exactly the same thing. So, clarity is obviously about how understandable the information is that you are sharing to the people with a whole range of health literacy levels and numeracy levels in the population. But we also know that people want different levels of information and different levels of detail. If people feel like they are being over-reassured or if things are over-simplified, and if we assume people can’t understand complex information, that’s also problematic.

And then transparency is really about providing data and the reasoning behind decision-making, and we find that when there isn’t enough transparency – so when not enough detail is shared – people can feel like something is being hidden from them, or you might get external experts starting to debate decisions or restrictions because they don’t actually have enough information to understand the basis of those decisions. Being transparent and communicating transparently can build trust, which is critical if you want the public to accept and act on things like the restrictions that you’re communicating about. And transparency also means being honest about uncertainty, of which there’s a huge amount obviously, during all of these decisions.

So, putting the modelling out there, that’s an example of sort of radical transparency – would be showing people exactly all of the data points and how everything goes into those decision-making models. But we also know that modelling data can be confusing, it can actually cause unnecessary concern in people. And what we saw a little bit is that talking too much about the modelling and the numbers in particular can actually have some unintended consequences; so, for instance, our research has shown that people who tested positive for COVID during the second wave started to experience stigma when the emphasis became solely on case numbers – day to day case numbers being reported all the time. So, in Victoria, the government struck a balance around sharing information, so there were very simple action-oriented public messaging, with also a more detailed datahub that provided more information for people who wanted to seek of that detail.

We also know that consistent messaging is more trustworthy and it’s easier to remember, and it’s easier for people to act on, but of course, there was very little that was consistent during the pandemic – during the second wave in particular; we saw changing evidence constantly, obviously changing case numbers, and the restrictions changed frequently. So, I think what the government sort of seemed to do in this context was to seek consistency where it could find it; so that meant consistency of the format, the timing in many cases, and the delivery method of communication. So, we had the premier, Daniel Andrews, standing up in press conferences every single day providing a heads-up when restrictions would be announced and would be changed, and then these examples of how social media was used to communicate daily information that was relevant, such as case numbers.

We also know that information and messaging about restrictions and policies needs to be accessible in terms of language and communication channels. So, while culturally and linguistically diverse groups were a key focus of a lot of the pandemic response and restrictions, we did see a range of challenges in the communication in this area. So official translations often occurred slowly or there were gaps or flaws in the translation. The consistency, that I talked about, of the message delivery also may have missed key channels if people didn’t look to the premier’s press conferences regularly. However, in many cases the community actually stepped up and filled some of these gaps to support and disseminate and tailor information about complex policy decisions is a really important element.

And finally, the credibility of the spokespeople is critical. We saw politicians across the different states being the primary spokespeople for pandemic restrictions and policy decisions, which allowed some consistency again. However, it also allows these decisions to become politicised, and people might react to them based on political values rather than public health behaviours. So, utilising medical and scientific experts to communicate some of this information allows people to maybe listen to what they’re saying without politicising that particular issue.

So, in terms of communicating about vaccine risks and the changing nature of these vaccine risks, we want to reassure people, but we also want to be cautious and realistic when we’re presenting risk. And we also need to differentiate risk for different populations or different segments of the population, but we also want a unified message that’s simple and easy to understand. So, there’s a range of different factors that are important when people are perceiving and evaluating risk, and these are things that we need to take into account when we are developing communication about this. You might see a hotel quarantine worker is at much higher risk of exposure to COVID than someone who works from home. And likewise, someone who is maybe a young woman might feel like they are much more at risk of a vaccine adverse event than an older man. So, personal circumstances is one of the key things that we can’t change, but we can address in our tailoring of communication.

And then we also can think about the shortcuts – the mental shortcuts – which are heuristics that we use when we are making decisions about or making sense of risk. So, we know that we have trouble understanding very, very rare risks and we often overestimate them, so that’s called compression. Or a rare outcome that’s very serious and has a lot of public attention might get more weighting in our minds than it actually might warrant based on how frequent it is; that’s availability. And then also, we know from other vaccination research that people are much more likely to fear a negative consequence of doing something – of taking an action – than they are to fear a negative consequence of doing nothing; and that’s omission bias. So, people would prefer sometimes not to vaccinate and take the risk of that than to take that decisive action and actually get vaccinated. And then finally, we use our social and personal values to weigh risk, so that’s around things like fairness and justice, and self-determination, or ability to make your own decisions.

So, if we’re trying to build confidence in a vaccine program it’s very important to compare different risks with great care. So, there’s some evidence that suggest if you compare a risk that is very familiar, and people choose to take it – something like not wearing a seatbelt while you’re driving – with something that’s very unfamiliar and not voluntary; that’s not apples to apples and it can actually cause harm. For instance, some women have become quite concerned about the birth control pill because all of a sudden, we’re talking about clots from the pill all the time, and they didn’t actually know all of that, or it’s creating fear in another area. It’s important to avoid overstating precision—so, this is changing all the time—we don’t necessarily know the denominator at the moment, so we can’t be overly certain when we say exactly what the risk is when we’re comparing it to other things.

And there’s also a lot of value in considering benefits to people other than avoidance of the disease, especially where we have low community transmission at the moment. So, that’s about finding out what motivates people to vaccinate; if it’s increased ability to travel, if it’s freedom from lockdowns, freedom from school closures, things like that. If we can speak to that rather than only focusing on the disease rates, that can make the risk-benefit equation more meaningful to people. And then we can see that visuals and decision aids, and things – tools that help people work through their decisions – are more effective than numbers alone. And finally, it’s really important to test messaging with different populations because what speaks to one group may be completely irrelevant to a different group. So, even in this fast-paced environment, we really need to make sure that we’re testing messages before we’re spreading them really widely. So, I thank you.

MIC CAVAZZINI:               One of the unifying themes of all our podcasts, is the behavioural factors to healthcare. For all the cutting-edge interventions in the world, and even the low-tech ones, it’s their uptake that often makes all the difference. We can’t criticise vaccine hesitancy in the community too much, when there are many examples of inertia in the institution of medicine as well.

In March 2020, the World Health Organisation issued a Tweet about the very novel virus saying, in all caps, “FACT: #COVID19 is NOT airborne.” It was accepted science, that respiratory viruses spread by attaching to droplets larger than 5 microns diameter, right? These might be spluttered a couple of metres at most, and we were told to religiously cough into our elbows and wash our hands.

But some scientists recognised very early the incidence of superspreading events in restaurants, call centres, cruise ships, and a choir rehearsal. In a gripping article for Wired magazine, Virginia Tech aerosol scientist Linsey Marr was interviewed about the uphill battle she and others faced helping overturn the dogma about airborne viral transmission. The WHO readily accepted their advice about air pollution—how particles from smokestacks and car exhausts would float around for hours in the air—but in discussions about microbial transmission, she and another eminent atmospheric physicist were seen as “epistemic outsiders,” according to Wired journalist Megan Molteni. Back in 2011 Linsey Marr had collected particles of influenza virus using air samplers in day care centres and aeroplanes, but she was unable to get her work published in the major medical journals. 

The 5 micron rule was so established, no one even knew where the primary evidence for it came from. Linsey Marr set a graduate student on the task who eventually uncovered a 1955 book titled ‘Airborne Contagion and Air Hygiene’ by an engineer from Harvard University. William Firth Wells had done some calculations predicting that particles any smaller than 100 microns might be capable of airborne transmission, and showed that guinea pigs exposed to air exhaust from a tuberculosis ward often got sick. The infections stopped when the air was irradiated with UV light.

In other work he had tested the belief that the nose and throat could filter out particles of TB bigger than 5 microns, and it seems that this is the figure that was fixed upon by the chief epidemiologist of the newly established Centre for Disease Control. Megan Molteni writes; “5 microns [became a] stand in for a general definition of airborne spread… over time, through blind repetition, the error sank deeper into the medical canon.” Linsey Marr and others who’d contributed to the understanding of airborne transmission were finally approached for an editorial that was published in the BMJ in April 2021, and the guideline organisations quietly updated their websites.

Now, of course, sceptics of strict public health interventions have leapt on the idea that cloth masks can’t possibly filter out micron scale aerosol particles and so are a total waste of time. Adam Creighton is a journalist who I singled out in the last episode, who on top of many strident articles for the Australian has tweeted, “Imagine having an IQ above 90 and thinking mask mandates stop viruses. Just like barbed wire keeps out mozzies.” If you’re listening, Adam, not only will masks indeed trap some of the larger particles, there’s also evidence that when worn correctly they restrict the airflow that carries aerosols.

Of course out of the lab it’s much harder to conduct a controlled experiment to determine whether masks have an effect at the population level. But an Australian study published in July in PLoS One was the first in the world to present compelling observational findings of this sort. The second COVID wave in Victoria last year provided a unique opportunity to examine this question because on July 23rd a mandate for mask-wearing in public places was implemented independent of any other public health intervention. Melbourne had been in soft lockdown for two weeks already and would later escalate to stage 4, but this provided researchers at the Burnet Institute with a brief window in which to carefully scrutinise transmission rates.

They found that the when the mask mandate was introduced, the growth rate of the outbreak turned a corner. Case numbers had been doubling every sixteen and a half days, but then they flipped to decreasing by half every 30 days. I heard the lead author, Nick Scott, present these findings and he was at pains to point out that this didn’t say anything about aerosol physics or masks per se. It was simply a demonstration that the policy of mask wearing had an effect. It could just be that when you see masks everywhere you’re more conscious of standing two metres apart and other behaviours that reduce viral transmission. But you need buy in from the community, and it was encouraging to see from photography of the Melbourne streets that compliance reached 98% after the policy came in. For more discussion around the squishy filling between policy and science I can recommend a recent review in BMC Infectious Diseases titled “COVID-19 false dichotomies and a comprehensive review of the evidence regarding public health.”

As Professor Allen Cheng told me, it is hard to communicate such nuance to a public anxious for certainty. He was Deputy to Victoria’s Chief Health Officer Brett Sutton during the lockdowns late last year, is a member of the COVID-19 Group at ATAGI, the Australian Technical Advisory Group on Immunisation, and continues to chair the TGA’s Advisory Committee for Vaccines. The interview was recorded by phone on the 31^st August.

ALLEN CHENG:  So, I’m Alan Cheng, I'm Director of Infection Prevention and Healthcare Epidemiology at Alfred Health in Melbourne, and Professor of Infectious Disease Epidemiology at Monash.

MIC CAVAZZINI:               We're all pretty used to the concept of lockdowns now and pretty sick of them. But when you and Brett Sutton advise the Victorian Government to bring them in last year, it was the first time anything like this had happened in Australia, in living memory anyway. How did you think it was going to go convincing people that this was necessary? And was it enough just to point to the mayhem overseas or to the modeling?

ALLEN CHENG:  Yeah, look, I wasn't involved in the first wave in Victoria in public health. But, so in the second wave, we obviously had the experience from the first wave. And we knew that it could be controlled and actually, all the Asian countries have done fairly well, in lockdown. Obviously, they're in different contexts, and there are things you can do in China, you probably can't do in Australia—Singapore is probably another good example. But from all those different countries, we knew that it was possible to get numbers down with lockdowns. And the countries that hadn't, or had been caught unawares such as Italy, really were having a pretty tough time. So I think it was easy to make that case then.

MIC CAVAZZINI:               At that presentation you and Jess Kaufman gave in May- “the need to maintain a social licence.” It’s very easy for disgruntled members of the public, including myself at times, to complain, you know, “Why am I not allowed to drive to go for a bush walk? But am I allowed to stand in the supermarket at the hardware store with hundreds of people? Why do I have to wear a mask outdoors, when there's no evidence of outdoor transmission?” I presume, as an infectious disease specialist, you're aware of all of these apparent contradictions, but that you have to set the settings at a conservative level to buffer for a degree of randomness and non-adherence? Is that the thinking?

ALLEN CHENG:  Yeah, so it I mean, the principles are that it needs to be proportionate. But you know, above all, , there needs to be some sort of overarching principle to say, “What are we trying to do by all of this.” And the overarching rationale for us was trying to reduce mass movement and mixing. You know, probably golf courses are the classic example of that where, transmission doesn't really occur on a golf course, I'm sure. But, you know, “there are only four reasons to leave home, except you can play golf,” that just doesn't really work. So it's not really consistent with just trying to keep everyone at home, and trying to reduce mass movement and mixing.

MIC CAVAZZINI:               Yeah,  there's so many little examples of that, you know, you might not, you might not catch it on the beach, but on the bus to the beach. Or okay, you shut down the buses, but then only the privileged people can get there. And even the mask thing, I think, is one that's been beat up. People might not catch COVID standing outside queueing for the bus. But can you trust everyone to pull their mask up when they step onto the bus? So would you say you have to have a conservative setting to account for those gaps in compliance?

ALLEN CHENG:  Yep. When we're sort of considering public health measures, we're not dealing with individuals, we're dealing with a population dimension. So the question is, “does a policy of masks work?” And that's the hard bit to convey, you know, one person not wearing a mask doesn't mean the policy’s failed. And the risk of focusing on one person doing the wrong thing is that it normalizes that for everyone. So probably the best example of that is in the UK, You know, Dominic Cummings, the Prime Minister's advisor, broke the walls and drove up to Durham from London when he wasn't meant to. And having that reported everywhere, sort of just said, “Well, you know, it's okay for him.”  And that goes the same with every restriction.

MIC CAVAZZINI:               Going back to the last year—even with the demonstrated effectiveness of lockdowns, and you know, you had the Victorian public largely on board, it must have been a big step to then introduce curfews on top of that, for the first time. How hard was that decision to make? And was a good evidence behind that or was it a Hail Mary pass?

ALLEN CHENG:  Yeah, look, when it was brought in on the second of August, last year—and there was really the feeling at that time that we really needed to throw the kitchen sink at the problem. We'd already brought in stage 3 restrictions. We'd already brought in stage three restrictions. So there was that, you know, stay at home. Then I think about the middle of July, there was mandatory masks everywhere. But the cases were still going up, you know, that probably stabilized, but probably about five or six hundred cases a day. And we did have some information that, you know, people were still going to each other's places in the evenings. And so, you know, having a curfew started relatively early, you know, it sends a clear message. And I think I think we had a reasonable amount of social licence early. And as the cases turned, people could see that, you know, “We're doing this and it's having an effect.” Obviously a little bit later became harder. And everyone said, Well, why can I go and visit my friends when there's only 100 cases a day and serve 600 cases a day?

MIC CAVAZZINI:               Yeah. So continuing on the curfews. Sydney now in the current outbreak has taken a slightly different tack from Melbourne. Rather than going city-wide, curfews were just applied to the 12 areas of concern. And this has been criticized for exaggerating the socio-economic disparity and stigma of areas where there's higher transmission. You know, high density neighbourhoods—English may not be the first language—the rules aren't always clear. You know, meanwhile, those living on the harbour or the green spaces are sharing obnoxious #iso pictures. #selfawareness. From a public health messaging angle, was that perhaps an own goal from New South Wales just single out certain neighbourhoods?

ALLEN CHENG:  I think it's a hard one. And I think it's pretty hard to second guess what they—what New South Wales—might have been considering at the time, and you know, what information they had to make their decision. But the issue is about proportionality. So they made the judgment that, you know, cases were concentrated in a particular area, Sydney's a big place, so the least restrictive intervention was to apply, you know, those stay at home orders or the tightest restrictions in the areas specifically. I think it's a difficult judgement, and this one of the principles that's come up, you know, COVID, does hit the most vulnerable people. And, if the restrictions, even if they were applied across Sydney, they would still be the ones that sort of bore the brunt of it. Over and over again, we see, where is the soft underbelly of your community, you know, Melbourne, obviously, public housing and some of those communities in the north and west. In Singapore, there was the foreign worker dormitories, so very crowded, sort of an underclass in Singapore to some extent. And that theme has come out over and over. It's easy to control in affluent neighbourhoods, but it's the people that are essential workers, the people that have lower health literacy, that this is, you know, Public Health 101.

MIC CAVAZZINI:               And that disparity has also become clear in regards to vaccination rates. There are some suburbs which lag far behind the national average for all sorts of reasons; access and health literacy and so on. Like, as you said, this isn't new to anyone in public health. Did you have the enough information about tackling these challenges? Did you have the tools to communicate to specific neighbourhoods

ALLEN CHENG:  Yeah, so the first thing to say about the vaccine rollout is that there's clearly a tension between, a trade-off between, speed and equity. So you, if you want to roll things out as quickly as you can, then the people who will take it up will probably be the people that least need it. It goes up quicker in, you know, more highly-educated people who are, you know, have cars and can go to clinics, and can use the internet to book the appointments quickly, and so on.

MIC CAVAZZINI:               Take time off work.

ALLEN CHENG:  That's probably a really good example there. But then there's equity. So to roll it out in nursing homes, will necessarily be slower. But we wanted to do that because they are the most vulnerable, that's where all the deaths—most of the deaths—have occurred. We knew this from a lot of other countries so France, for example, had said, "Okay, we're going to give it to people in nursing homes first," but it just seemed to take forever to do that. But that was the decision they made to say, “We're going to sacrifice speed for protecting the most vulnerable.”

MIC CAVAZZINI:               Yeah, I mean, from the peanut gallery, it's easy for me to crit—"You know, aged care residents, well they're not going anywhere. How hard would it be to get nurses in there with vials?"

ALLEN CHENG:  Yeah, I mean, it turns out to be much harder, because—so when I got my vaccine at the hospital no one had to explain any technical terms to me—obviously, do a quick questionnaire—you know, one nurse could probably do 12 vaccines in an hour. In a nursing home, someone has to get consent before, they have to sit with the patient for 15 minutes before they can move on to the next one. So you can probably only do three or four vaccines and people you might have to circle back for and those sorts of things. So it is going to be much slower in those areas.

MIC CAVAZZINI:               I mean, even more so. Just this morning, the news was about a growing outbreak in Wilcannia and other Aboriginal communities. And yes, you could have sent resources out there a couple of months ago, but like you say, you wouldn't have got everyone in one day—there are people coming from even more remote townships, there are people harder to explain the concept to, So there's no easy wins.

ALLEN CHENG:  Yeah, but certainly First Nations before we're in Phase 1B for memory. So we knew that we'd have to give it more time for the vaccine to get out to them. And it's been a struggle, but it'll get there.

MIC CAVAZZINI:               Interestingly, from, the latest New South Wales health data for the Delta outbreak, it shows that there are twice as many infections among those in their teens or 20s, as there are for those in their 40s and 50s. And, you know, we understand that young people are more mobile and more social. They're probably the ones in those more exposed service jobs. You can slice and dice this to the nth degree and other vulnerable groups that aren't at the top of the list, are people like transport workers. Several hundred of Sydney’s bus drivers and other transport workers have been infected with SARS-CoV2 and in California last year this sector made up about a third of COVID-related deaths. Has it changed the thinking around these strategies?

ALLEN CHENG:  Yeah, so it's always known that younger people interact more than older people. It's known that children very important transmitters are flu and there's some evidence to say if you vaccinate children, then you can reduce transmission in older people. The judgment that was made for COVID was really that evidence was best for direct protection. And so we wanted to vaccinate older people because they are the people that get complicated COVID. And they're the people that would die if they got it. I still think that, you know, simplest is best. So there was a national decision that after the first cohorts- so obviously healthcare workers and hotel quarantine workers- that there wouldn't be sort of this dissection of the workforce, because it just complicates things to some extent. You know, what is it have to go and define a transport worker doesn't include the people that are doing signalling as well as the driver? You know, where do you draw that line and how do you prove it? That whole thing will slow things down.

MIC CAVAZZINI:               There’s been a lot of discussion about how to incentivise those hesitant to get the vaccine. Prime Minister Scott Morrison slammed the Opposition's admittedly uninspired idea of offering cash incentives. But it doesn’t seem so different than the No Jab No Pay policy introduced in 2015 by the then Social Services Minister, Scott Morrison. That policy withholds welfare payments from parents who do not present their children for the National Immunisation Program. What is the right balance between carrot and stick when it comes to preventative health?

ALLEN CHENG:  Yeah, look, the principle in terms of these carrots and sticks is you want the least restrictive policy to achieve your aim. So if you think that cash incentives would achieve high uptake, then yeah, that's fine. For COVID vaccines, there is also the Occupational Health lens. So for people, you know, working at a hospital, it's about providing a safe workplace. And so there's sort of this hierarchy, you know. You start with, "Okay, the vaccine is available, coming and get it." Then there's sort of actively promoting it and making sure that all the barriers are addressed; access, information, and so on.

And then, you know, to turn the screws, you might say, "Well, you need to tell your employer if you've been vaccinated or not, so that they can work out what you can or can't do." And then you if have to turn the screw a bit more you'd say, "Well, the employer has to report what proportion of their workforces are vaccinated." So obviously, aged care is a good example of that. And then, you might say, "Well, actually, for all aged care facilities, we're going to make your data public, you have to tell us how many of your employees are vaccinated, and we will tell the public so they can compare and shine the spotlight on you." And then you might say, "You can't enter aged care facility or hospital unless you've been vaccinated." So, you know, there's a graduated sort of hierarchy of and that comes down to how can you achieve your aim by the least restrictive method.

MIC CAVAZZINI:               Widely-accepted ethical frameworks recognise the principle of bodily autonomy—that you can’t force any medical intervention on unwilling participants. By and large the law is consistent with this, but not all the time, writes Maria O'Sullivan from the Castan Centre for Human Rights Law at Monash University. An exception to this principle can be found in sections 116 and 117 of the Victorian Public Health Act, which would compel people to undergo medical examination or treatment without consent if a public health crisis required such caution.

It’s hard to imagine this legislation actually being enforced, but subtler forms of coercion have already been put in place in regards to vaccines against COVID-19. In early August, big Australian companies SPC and QANTAS announced that vaccination would be mandatory for their staff. On the 20^th August the NSW Health Minister made a similar announcement with respect to all health workers a sixth of whom appear reluctant to get the jab. But does this mean you could fire an employee who refused? And what right of recourse would they have?

In an article for the Australian Financial Review, some lawyers expressed the opinion that high risk workplaces like aged care and quarantine would be seen by any jurist to meet conditions for a no jab-no job type policy. But it might not be considered “lawful and reasonable” to apply the same standards to other settings. This hasn’t been tested in the courts yet, and as usual there are gaps between state and commonwealth legislation.

In Melbourne last year a café owner did take the Deputy Public Health Commander to the Supreme Court, arguing that the 5pm curfew was "unreasonable…unlawful and a breach of her human rights". Although Australia doesn’t have a Bill of Rights in the Constitution, there is a human rights charter in Victorian law that protects the right to freedom of movement. However the judge ruled that the defence had established "that the restrictions on human rights caused by the curfew were proportionate to the purpose of protecting public health."

We’ve already talked about withholding of federal welfare payments as an incentive or coercion for parents to vaccinate children in line with the National Immunisation Program Schedule. All but three jurisdictions have a similar “No jab, no play” legislation stating that kids cannot attend daycare unless vaccinated. Interestingly, however, the presence of such policies does not predict higher rates of vaccination coverage when you compare to states that don’t have them in place. As Maria O'Sullivan writes, while there may be an argument for making clearer and more consistent legislation around vaccine requirements, there really is no shortcut to winning public trust and cooperation.

This is especially true in an environment of high anxiety and novelty. The COVID-19 vaccine developed by AstraZeneca was approved by the Therapeutic Goods Anxiety in February but not long after, there were a few reports of thrombosis among vaccine recipients in Europe. Despite Astrazeneca’s protests about the safety data, Denmark was the first country to suspend administration of the vaccine on the 11^th March, and it was soon followed by Austria, Italy, Ireland and eight more countries in the following days. Australia had not seen serious side-effects from either vaccine from around 160,000 doses administered and in a statement on the 16^th March ATAGI said we should carry on.

The European regulator conducted a review and concluded that with 25 cases of blood clots from 25 million doses, the link was plausible but that disease was still a far greater risk. Those European countries resumed their programs, and ATAGI updated its guidance to warn that any history of anaphylaxis following previous vaccines should be a contraindication for the AstraZeneca vaccine. Only later would this vaccine-induced thrombosis with thrombocytopenia be better characterised, a syndrome similar to that sometimes seen in response to heparin. I asked Allen Cheng what kind of numbers the early AZ trials gone through, and whether he and his colleagues at ATAGI were happy with the quality of the evidence.

ALLEN CHENG:  You know, vaccine trials are usually relatively being compared to other drugs. You know, Pfizer and AstraZeneca, the data they were analysing, were in tens of thousands of people, so that was fine. And they both clearly met the regulatory bar for safety and efficacy. But you know, in a trial of 30,000 people, you don't expect to see a side effect less than one in 10,000.

MIC CAVAZZINI:               Yes, the process happened quickly, but there weren't any steps that were skipped.

ALLEN CHENG:  Yeah, you know, it may meet the regulatory bar, but you still need to continue to do what's called pharmacovigilance, or post marketing surveillance to see, you know, what else might happen. And there's a group called the Brighton collaboration and they had come up with this long list of things that need to be looked for in trials and in post marketing, surveillance, and in fact, clotting was on that list. But there's a huge range of other things that might be expected.

MIC CAVAZZINI:               Interesting. As the weeks progressed—so where are we now, end of March—as the weeks progressed it seemed from overseas that younger people were more vulnerable to this clotting side effect, and the first case in Australia occurred on the 1^st April, a 44 year old man who had blood clots in his gut, his liver and his spleen. The following Thursday the 8^th, I heard that snap press conference by the PM announcing that AstraZeneca vaccine was no longer first line for people under 50. I remember thinking a bit cynically, “Oh the Government doesn’t want to be responsible for any vaccine deaths in an election year.” But no, that was entirely based on ATAGI’s call at the time?

ALLEN CHENG:  Yeah, absolutely. So when we'd met after the first case, had been reported on—memorably on Good Friday—and then the second case, we met on the seventh and the eighth of April. So what we really had was a lot of uncertainty about, you know, actually, how common is this side effect. So we had three very imperfect sources of information; there was data from the UK where they had used a case definition, but we didn't have clear line of sight to the denominator by age—how many people had had which vaccines. In the European data, they had just done a database stretch. So they looked at their reporting database and said, anything with platelets, we'll call that TTS, because they couldn't drill down to individual countries. And then in Australian data, we had all that, you know, all the denominator and numerator data, but we just didn't have very large enough numbers to make any statistical judgment on that. So there were just so many uncertainties…

MIC CAVAZZINI:               So on the 16^th April— a week later—it was announced that a 48 yo woman in Australia had died four days after receiving her first Astrazeneca shot. The TGA said this was only the third case of clotting linked to the vaccine and put the risk at one in 295,000. Within a week, three more cases were reported. On the 23^rd of May ATAGI added a few groups with specific family histories to the list of those who should opt for the Pfizer vaccine. At which point did you go from thinking, “this is what we do, this is the way we always deliver advice” to actually worrying that  “this is going to be a problem for the messaging campaign?”

ALLEN CHENG:  I mean, I think, you know, we recognize a unexpected safety signal is always going to be difficult. So I think, you know, anaphylaxis is sort of recognized as a side effect after, you know, anything, basically, so that's relatively easier to talk about. The public do understand that, you know, allergies do occur. But we didn't really know how severe it would be. The early reports from the UK suggested, you know, a quarter of the people that had this complication had died. And then what we're trying to weigh that up against is, what is the chance of a COVID outbreak in the future? Remembering that in April, there wasn't much COVID in Australia at all. So, you know, there are just too many unknowns there to message.

MIC CAVAZZINI:               Yeah so by June 17^th in Australia there had been 60 cases of thrombotic thrombocytopaenia but only 2 deaths. It seemed like the risk of vaccine-induced TTS was crystalising at around 3 per 100,000 in people aged under the age of 60. So when that came out, ATAGI recommended that the cut off be shifted to under sixties, for the Aztrazeneca vaccine. But the ATAGI statements had both been framed with lines like this, “COVID-19 Vaccine AstraZeneca can be used in adults aged under 50 years where the benefits are likely to outweigh the risks for that individual and the person has made an informed decision”… and elsewhere … “People who choose to delay vaccination until a vaccine other than AstraZeneca is available should be aware they may not be protected against COVID-19 for months.” To most of our listeners, our physicians listening, such qualifiers are what they expect from ATAGI and the TGA, you see them for every drug and jab; “Here are the numbers and it’s for a patient and their doctor to weigh these risks and benefits up” The real difference here was that it wasn’t one patient it was 20 million odd all at once?

ALLEN CHENG:  Yeah, and that's the difficulty. We're trying to provide advice that accommodates all the different people in Australia, you know, different ages, all their personal circumstances. And so what we fell back on, it's the principle of autonomy; that, you know, we present the information that we know, we spell out what we have assumed, and what we don't know. We tried to frame this in terms of that sort of absolute numbers, you know, "These are the risks, and these are the benefits" and trying to quantify that. But there is a qualitative element to this; so, protecting loved ones, there's contributing to the community, there's reduced anxiety, if you're vaccinated, you won't be as worried about getting COVID. That's not really quantifiable, and that’s subjective, so doing it at a mass scale is a lot, obviously a lot more difficult.

MIC CAVAZZINI:               As you say, there were there were few cases of COVID-19 in the country at the time. But ATAGI has criticised as being naïve or operating in some perfectionist bubble, some ivory tower, with that kind of risk judgment. But you know, ATAGI didn’t just consider the “risk of severe illness and death” but also and I quote; “The expected vaccine supply over the months ahead and the impacts of any change in recommendation on the COVID-19 vaccine program.” There's even uncertainty about the virus mutations themselves. There was I thinking that, "Surely it was always likely that a more virulent strain would come along." But I just read the other day, Professor Eddie Holmes, who published the SARS-CoV-2 genome, he said delta came around a lot sooner than expected. You know, with flu you expect significant mutation every couple of seasons, so…

ALLEN CHENG:  Yeah, so, you know, again in in April, I think delta wasn't even called delta then. But, you know, it wasn't really sure how much more transmissible it was. We were most worried about alpha as something that was spreading more quickly and in the UK, but it really wasn't known exactly how difficult delta would be to control.

MIC CAVAZZINI:               But by mid-July the public was getting nervous about how hard it was to get an appointment for a Pfizer vaccine, and vaccination centres were frustrated by the boxes of Astrazeneca lying around that no one wanted. The Prime Minister told 2GB radio that the vaccination rollout had been stalled by ATAGI’s “very cautious” advice. You were asked to respond by the Guardian and said that, “They run the program, we provide advice – those are our terms of reference,” and that “we’re always very conscious of the impacts of our recommendations on the program and vaccine confidence generally.” Given all the different hats you wear or you’ve worn, I’m sure you could see the government’s predicament about wanting to communicate a definitive message. We know that isn’t always possible in medicine. Was there a way to do this better here? Have we learned any lessons about how to resolve this tension between academic advice and government, nationwide rollout?

ALLEN CHENG:  Yeah, I mean, this is the issue that, everyone wants a black and white answer, you know, "Do this, don't do this. And everything will be fine." And public health isn't like this. And you know, for ATAGI, our terms of reference to provide advice to the Health Minister, you know, we don't have a role, a formal role, in public communication, that's the government's job to do. We thought we'd very carefully wordsmithed our advice to government, so, when this all happened, we sort, of went back to say, you know, “Have we done well enough to convey all of those uncertainties so that they can do the communications appropriately. And, you know, it's difficult, and politicians have to explain it—they're not mathematical modelers. You know, in a normal situation, for other tricky policy issues, there would be, green papers and white papers and, and in pandemic times this just as possible to do all of that. You might be lucky to have a few meetings with key stakeholders to signal what you're thinking or to test whether something's feasible or not, but we're really having to make a decision very quickly.

MIC CAVAZZINI:               And the Prime Minister and his defence did say repeatedly that people should talk to their ow their own doctor about the risks. But, I guess, many people don’t have a trusted GP, it’s this chain of communication that’s difficult to oversee. I don’t know if we can blame ATAGI or the Government too much. I wonder if we should ask questions of the media and their thirst for drama that might have freaked people out about the vaccine more than necessary?

ALLEN CHENG:  I mean, the media haven't been too bad, I understand they're doing their job. And there is that sort of—what do they call it? “If it bleeds, it leads,” you know, they focus on individuals and talking about population level, public health isn't always the most interesting story for them. I understand that there's a whole academic literature in in journalism called constructive journalism to try and come up with solutions rather than just point out problems. But probably worth talking to a journalist about that.

MIC CAVAZZINI:               I’m curious about your opinion on a very strongly worded piece a very strongly worded piece for the Sydney Morning Herald by Dr Nick Coatsworth, RACP Fellow and ex Deputy CMO of Australia. He was having a go at all the academics who’d indulged this news-hungry media and spelled out doom and gloom forecasts for the pandemic. Stepping outside their “swim lanes”, he said, to criticise government policy. He starts by presenting the NSW’s approach as very proportionate and effective until delta came along, and then, I quote, “Unfortunately, the delta variant showed the limitations of this approach. [But] the philosophy of the risk-averse experts is self-fulfilling. Complain long enough that a government hasn’t gone hard and fast enough, and eventually you will get it right, no matter how wrong you have been in the past... As experts, we need to avoid positioning ourselves behind different policy positions… leave the policy to those who actually have responsibility for the community and for weighing up the consequences of COVID-19, be they physical, mental, social or economic.” Discuss.

ALLEN CHENG:  Yeah look, I mean, I have some sympathy for that. You know, I've been on both sides, I’ve been on….

MIC CAVAZZINI:               Yeah exactly, that’s why I’m asking you.

ALLEN CHENG:  Yeah, I've been on the commentator side, I've been representing government as well. And, as before, when you asked me about New South Wales, there are things that they know that I just won't know; They know their communities better, they have access to so much more data than I would. And so I think the best role of a commentator that is not in government is to explain a complex situation. And it's not to say that if someone makes what we think is a completely strange decision that you might not question that, but you need to be very careful. No one is ever going to get back to a commentator and say, “Actually, last year said this, and turned out not to be true.” Whereas for government officials, you're always on the hook for, you know, the decisions you make. So the accountability isn't the same in that sense. Is that suitably diplomatic?

MIC CAVAZZINI:               That’s a very good answer. And Nick Coatsworth’s article is a compelling piece of writing, and to an extent, I agree with what you have said. And it's particularly relevant now that there's all these different models floating around, are we following the right model? In defence of some of the other experts who aren't in the room with the politicians, but speaking out, I guess, when some of the decisions appear to be made on the basis of political expediency rather than expert advice, and then the loudest voices in the media haven't the slightest bit of expertise or impartiality, I can understand why other experts feel compelled to step out and create some balance in the science that's been discussed.

ALLEN CHENG:  Yeah look, I mean, in Australia, you know, by and large politicians and public health have been on the same page. So I'm sure there's tensions in every cabinet and in National Cabinet. But I think in general, there are probably better ways to question that then tried to do it in a public space, or you risk undermining the public health response and confidence in public health in general. And this, Mike Daube who’s one of the great sort of anti-tobacco campaigners sort of said, there's an inside strategy and an outside strategy. So if you are within the tent, and you can influence government directly, then you should use that path and take the inside path. If you're not inside the tent, and you can lob grenades happily from outside, then you can do that. But you should do that responsibly. And, things best work if you're trying to pressure government by doing both. It's coordinated so that the people outside know what to say and look people inside, you know, have a clear path of what is the right thing to do. And then using both of those then you can achieve the best outcome from public health.

MIC CAVAZZINI:               Many thanks to Allen Cheng for giving me his time during this difficult period, and also to Jessica Kaufman for allowing me to share her presentation with you. The views expressed are their own, and not necessarily those of the Royal Australasian College of Physicians. My appreciation also to all the RACP physicians and other professionals who make up the podcast editorial group. You are all very patient with my questions. For more reading on this topic please go to our website racp.edu.au/podcast. There you can sign up to a mailing list for new episode alerts, but the easiest way to subscribe is through a phone app like Apple Podcasts, Spotify, Castbox or Overcast. Just search Pomegranate Health, and please leave a review if you want to help others find us too. Feel free to send any critical feedback to podcast@racp.edu.au. It’s always great to hear what you think, and how I can make the podcast better. I’m Mic Cavazzini. Bye for now.