Archive for September 10th, 2023

Coronacast, food sources and pandemics

September 10, 2023

Tell them the truth and let them decide for themselves.

Naomi Negata, The Expanse

coronavirus statistics on screen
Photo by Markus Spiske on

I’m a regular listener of the weekly ABC Radio National show (via podcast) Coronacast. Dr Norman Swan and health reporter Tegan Taylor have been evidence based, trusted advisors on COVID-19 and other nasties (as Tegan puts it), vaccines, masks, and ventilation since soon after the start of the pandemic.

I love the show, its roughly 10 minute duration, no-nonsense approach, and attempts at comedic levity.

The title of the episode on August 16 2023 was Hello furry mammal are you the next pandemic?

The topic of zoonosis was discussed (my highlighting, here and elsewhere below):

Tegan Taylor: And so to today’s topic, Norman, zoonoses is a word that we all became rapidly familiar with at the beginning of the pandemic, it’s when diseases come from the animal kingdom into humans and vice versa, although we are part of the animal kingdom. And it’s one thing that we have to continue to watch, especially as we become so incredibly globalised. And in the context of farming, it’s often a breeding ground not just for the animals that are being farmed, but also for potential pandemics. And it’s something that scientists are watching particularly closely at the moment because of avian influenza.

Norman Swan: Yes, and actually a new paper on COVID-19 in mink, you might remember that 2020, 2021 there were these mass slaughters of mink in the Netherlands and Denmark, because what they showed was that there was COVID-19 to a very significant extent, maybe 60% or 70% prevalence in some mink populations, farmed mink, and that it was getting into humans and humans were reinfecting the mink, so there was what they call reverse zoonosis.

Tegan Taylor: Where we are giving it to the animal.

Norman Swan: Yes, that’s right and at least catching it from the animals. And this is where the worry is with these zoonoses, and we’ll come to flu in a moment, is that you get intermingling of viruses and the virus pops out as a very different virus. And that could be a source of another pandemic in the future.

They move on to H5N1, an influenza strain that has long been watched by disease outbreak authorities.

Norman Swan: Which is why they slaughter these populations because you want to reduce these populations. Fur is a discretionary item but food isn’t, which is why pig farms become very interesting.

Tegan Taylor: So that’s coronaviruses broadly in mink but hasn’t there been flu in mink as well?

Norman Swan: Yes, a recent report from Finland of fur farms…so these are farms that have foxes, mink and raccoon dogs. Remember raccoon dogs?

Tegan Taylor: They are very cute.

Norman Swan: They are very cute, but they carry coronavirus, as we know from the market story in Wuhan. So this is a survey from Finland very recently showing that the avian flu has spread into these populations of mink, foxes and raccoon dogs. So for those who like to be technical about this, this is influenza A and the type is H5N1 avian flu.

But this is where it starts to get very close to human beings because particularly mink are thought to be very similar.

And then there’s pig flu, swine flu, and swine flu is again…a survey in Cambodia of pig farms has shown an enormous variation of swine flu amongst pig populations, about 4,000 nose swabs from pigs, also looking at humans as well, and found that these mass variations of swine flu in the pig population, and also evidence that you’re getting reverse zoonoses, that humans are infecting the pig population. This is what happens. And food is not a discretionary item like fur.

Soon thereafter, we have this exchange:

Tegan Taylor: Yeah, it is a pretty confronting reminder of where food comes from, and not just the impact on animals, also the impact on humans.

Norman Swan: But we are slaughtering chickens, we have slaughtered millions and millions of chickens on chicken farms to prevent the spread of avian flu. And the potential is there to do that for pigs as well. But these are food sources, protein sources that are needed by the world’s population.

Tegan Taylor: Should we be rethinking our farming methods if we want to be controlling for future pandemics?

Norman Swan: The interesting contrast is between flu and COVID-19, we actually have quite good…it’s not brilliant, but we have quite good influenza monitoring systems. So we’re picking it up in pigs, we’re looking at pigs, we’re picking it up in mink farms in Finland, what we’re not doing is systematically surveying for COVID-19. If we’re picking it up, it’s almost accidental along the way on PCR testing. And so we’re not monitoring all emergent viruses.

Notice that Norman’s response to Tegan’s question is to change the subject to virus monitoring in pigs and mink. But the question was not about virus monitoring, but whether farming methods should be reconsidered.

Then there are statements like this in the exchange:

  • “Fur is a discretionary item but food isn’t.”
  • “And food is not a discretionary item like fur.”
  • Chickens and pigs “…are food sources, protein sources that are needed by the world’s population.”

Tegan’s question about rethinking our farming methods is important and one that few seem to want to seriously consider the implications of.

Of course it’s true, as Dr Swan says, that food isn’t a discretionary item, but the source of that food, of protein sources, does not have to be animals.

So, fur vs food as discretionary items is a false dichotomy.

I would really like to hear Tegan’s question considered further on Coronacast.

Another ABC RN podcast is Big Ideas. A recent episode of which was titled COVID, Zoonotic diseases, and the next pandemic. The intro starts with this:

Throughout human history, infectious viruses have moved between animals and humans without much fanfare. These are known as Zoonotic diseases. But every so often, they set off a chain reaction that can’t be contained, like the bubonic plague, or COVID-19. But the collective experience of COVID has given the world many lessons about what to — and what not to do — the next time there’s a Zoonotic leap. So what are those lessons, and is humanity able to not repeat the same mistakes?

The host, Olivia Willis, interviews Eddie Holmes, NHMRC Leadership Fellow and Professor of Virology in the School of Medical Sciences, University of Sydney, and Kris Helgen Chief Scientist and Director of the Australian Museum Research Institute (AMRI).

After an interesting interview, Olivia asked asked Eddie and Kris this question:

In thinking about stopping the next pandemic, I’d love to get both your perspectives on what you think is the single most important step right now to stop that happening.

Eddie responded by giving three things, two of which he thinks are doable:

  1. Make universal vaccines rather than the virus strain specific vaccines we have now.
  2. Stop the live animal trade or have better regulation and testing for viruses on a regular basis.

The third thing he says, is stopping the consumption of meat. He admits that he is being “controversial”, and thinks it won’t happen. In his words:

Consumption of meat is the number one thing for climate change and for these emergents. It’s a really big thing, right. I hate to say it. But it really is. And that, I think, would have a major effect on the number of viruses we are exposed to.

Kris immediately followed on from Eddie’s comment by saying that:

And that reliance on meat has to do with land clearing, it has to do with the wildlife trade, it has to do with all these types of things.

Eddie agreed enthusiastically, then continued with:

Factory farming too. In countries like Australia, the pig industry is continually a threat for influenza virus and other viruses too, and these animals are kept in huge numbers…and foot and mouth…would wipe out that industry very easily. So, our reliance on meat which is getting bigger…in terms of climate change, it’s just amazing. The beef industry, particularly. The effect that has on climate change is absolutely enormous.

This brings us back to Tegan’s question about rethinking farming methods.

Yet another ABC staple is Landline. In a recent episode, in addition to a story (one of a number recently) attempting to improve the image of the live export industry (cattle in this case), there was a story about the scale of the livestock sales business and the enormous number of cattle regularly trucked into stockyards, sometimes thousands of kilometres, from various parts of Australia and sold at auction to customers in Australia and other countries.

This reality along with the enormous number of animals in factory farms probably informs Eddie’s skepticism about the likelihood of ending meat consumption.

Although elimination is highly unlikely (an understatement) in the near future, significant reduction should not be, and we as consumers have control over this.

As a vegan, I obviously want to see meat consumption reduced primarily for the sake of the animals, but climate change and health (pandemic risk, anti-microbial resistance risk, preventable diseases of lifestyle) are also incredibly important factors, and if attention to these things helps get us to a net reduction of suffering, that’s fine with me.

Although there is an increased awareness now, even compared to a few years ago, I don’t know whether we’ll do enough towards climate change mitigation, better health outcomes, or reduced animal suffering in my lifetime. I’m not currently optimistic.

Something has to change, if for example, we want to reduce the pandemic risk and mitigate the worst effects of climate change.

It’s up to us though, and no-one is coming to save us from ourselves, as Carl Sagan’s Pale Blue Dot always reminds us.

Unless someone like you cares a whole awful lot, nothing is going to get better. It’s not.

Dr Seuss, The Lorax