Captain James Cook arrived in the Pacific 250 years ago, triggering British colonisation of the region. We’re asking researchers to reflect on what happened and how it shapes us today. You can see other stories in the series here and an interactive here.

Aboriginal and Torres Strait Islander listeners should be aware the podcast accompanying this story contains the names of people who are deceased.

It’s 250 years since Captain James Cook set foot in Australia, and there’s a growing push to fully acknowledge the violence of Australia’s colonial past.

On today’s episode of the podcast, historian Kate Darian-Smith of the University of Tasmania explains that the way Australia has commemorated Cook’s arrival has changed over time – from military displays in 1870 to waning interest in Cook in the 1950s, followed by the fever-pitch celebrations of 1970.

Now, though, a more nuanced debate is required, she says, adding that it’s time to discuss the violence that Cook’s crew meted out to Indigenous people after stepping ashore at Botany Bay.

“I think discussing those violent moments is quite confronting for many Australians, but also sits within wider discussions about Aboriginal rights and equality in today’s Australia,” Darian-Smith told The Conversation’s Phoebe Roth.

In her companion essay here, co-authored with Katrina Schlunke, Darian-Smith argues many of the popular “re-enactments” of national “foundation moments” in Australia’s past have elements of fantasy, compressing time and history into palatable narratives for mainstream Australia.

Everything you need to know about how to listen to a podcast is here.

Additional audio credits

Kindergarten by Unkle Ho, from Elefant Traks.

Podcast episode recorded by Phoebe Roth and edited by Sophia Morris.

Tasfilm report on the 1970 commemorations of Cook’s arrival.

1970 news report of protest.

David Crosling/AAP

Captain James Cook arrived in the Pacific 250 years ago, triggering British colonisation of the region. We’re asking researchers to reflect on what happened and how it shapes us today. You can see other stories in the series here and an interactive here.

Editor’s note: This is an edited transcript of an interview with John Maynard for our podcast Trust Me, I’m An Expert. Aboriginal and Torres Strait Islander readers are advised this article contains names of deceased people.

There are a multitude of Aboriginal oral memories about Captain James Cook, right across the continent.

As the research from Deborah Bird Rose shows, many Aboriginal people in remote locations are certainly under the impression that Cook came there as well, shooting people in a kind of Cook-led invasion of Australia. Many of these communities, of course, never met James Cook; the man never even went there.

But the deep impact of James Cook that spread across the country and he came to represent the bogeyman for Aboriginal Australia.

Even back in the Protection and Welfare Board days, a government car would turn up and Aboriginal people would be running around screaming, “Lookie, lookie, here comes Cookie!”

I wrote about Uncle Ray Rose, sadly recently departed, who’d had a stroke. Someone said, “How do you feel?” And he said, “No good. I’m Captain Cooked.”

Cook, wherever he went up the coast, was giving names where names already existed. Yuin oral memory in the south coast of NSW gives the example of what they called Gulaga and Cook called “Mount Dromedary”:

[…] that name can be seen as the first of the changes that come for our people […] Cook’s maps were very good, but they did not show our names for places. He didn’t ask us.

Cook has been incorporated into songs, jokes, stories and Aboriginal oral histories right across the country.

Why? I think it’s an Aboriginal response to the way we’ve been taught about our history.

I came through a school system of the 50s and 60s, and we weren’t weren’t even mentioned in the history books except as a people belonging to the Stone Age or as a dying race.

It was all about discoverers, explorers, settlers and Phar Lap or Don Bradman. But us Aboriginal people? Not there.

We had this high exposure of the public celebration of Cook, the statues of Cook, the reenactments of Cook – it was really in your face. For Aboriginal people, how do we make sense of all of this, faced with the reality of our experience and the catastrophic impact?

We’ve got to make sense of it the best way we can, and I think that’s why Cook turns up in so many oral histories.

I think wider Australia is moving towards a more balanced understanding of our history. Lots of people now recognise the richest cultural treasure the country possesses is 65,000 years of Aboriginal cultural connection to this continent.

That’s unlike anywhere else in the world. I mean no disrespect, but 250 years is a drop in a lake compared to 65,000 years. From our perspective, in fact, we’ve always been here. Our people came out of the Dreamtime of the creative ancestors and lived and kept the Earth as it was in the very first day.

With global warming, rising sea levels, rising temperatures and catastrophic storms, Aboriginal people did keep the Earth as it was in the very first day to ensure that it was passed to each surviving generation.

There was going to be a (now-cancelled) circumnavigation of Australia in the official proceedings this year, which the prime minister supported. But James Cook didn’t circumnavigate Australia. He only sailed up the east coast. So that’s creating more myths again, which is a senseless way to go.

Personally, I have high regard for James Cook as a navigator, as a cartographer, and certainly as an inspiring captain of his crew. He encouraged incredible loyalty among those that sailed with him on those three voyages. And that has to be recognised.

But against that, of course, is the reality that he was given secret instructions by the Navy to:

With the consent of the Natives to take possession of the convenient situations in the country in the name of the king of Great Britain.

Well, consent was never given. When they went ashore at Botany Bay, two Aboriginal men brandished spears and made it quite clear they didn’t want him there. Those men were wounded and Cook was one of those firing a musket.

There was no gaining any consent when he sailed on to Possession Island and planted that flag down. Totally the opposite, in fact.

And the most insightful viewpoint is from Cook himself, who wrote that:

all they seem’d to want was for us to be gone.

James Cook wasn’t your normal British naval officer of that time period. To get into such a position, you normally had to be born into the right family, to come from money and privilege.

James Cook was none of those things. He came from a poor family. His father was a labourer. Cook got to where he was by skill, endeavour, and, unquestionably, because he was a very smart man and brilliant at sea. But it’s also from that background that he’s able to offer insight.

There’s an incredible quotation of Cook’s where he says of Aboriginal people:

They live in a Tranquillity which is not disturb’d by the Inequality of Condition… they live in a warm and fine Climate and enjoy a very wholsome Air.

Now, Cook is comparing what he is seeing in Australia with life back Britain, where there is an incredible amount of inequality. London, at the time, was filthy. Sewerage pouring through the streets. Disease was rife. Underprivilege is everywhere.

In Australia, though, Cook sees what to him looks like this incredible egalitarian society and it makes an impact on him because of where he comes from.

But deeper misunderstandings persisted. In what’s now called Cooktown there are, at first, amicable relationships with the Guugu Yimithirr people, but when they come aboard the Endeavour they see this incredible profusion of turtles that the crew has captured.

They’re probably thinking, “these are our turtles.” They would quite happily share some of those turtles but the Bristish response is: you get none.

So the Guugu Yimithirr people go off the ship and set the grass on fire. Eventually, there’s a kind of peace settlement but the incident reveals a complete blindness on the part of the British to the idea of reciprocity in Aboriginal society.

The impact of 1770 has never eased for Aboriginal people. It was a collision of catastrophic proportions. The whole impact of 1788 – of invasion, dispossession, cultural destruction, occupation onto assimilation, segregation – all of these things that came after 1770.

Anything you want to measure – Aboriginal health, education, employment, housing, youth suicide, incarceration – we have the worst stats. That has been a continuation, a reality of the failure of government to recognise what has happened in the past and actually do something about it in the present to fix it for the future.

We’ve had decades and decades of governments saying to us, “We know what’s best for you.” But the fact is that when it comes to Aboriginal well being, the only people to listen to are Aboriginal people and we’ve never been put in the position.

We’ve been raising our voices for a long time now, but some people see that as a threat and are not prepared to listen.

An honest reckoning of the reality of Cook and what came after won’t heal things overnight. But it’s a starting point, from which we can join hands and walk together toward a shared future.

A balanced understanding of the past will help us build a future – it is of critical importance.

Everything you need to know about how to listen to a podcast is here.

Additional audio credits

Kindergarten by Unkle Ho, from Elefant Traks.

Marimba On the Loose by Daniel Birch, from Free Music Archive.

Podcast episode recorded and edited by Sunanda Creagh.

Uncle Fred Deeral as little old man in the film The Message, a film by Zakpage, to be shown at the National Museum of Australia in April. Nik Lachajczak of Zakpage.

In today’s episode, Clare Collins, a Professor in Nutrition and Dietetics at the University of Newcastle, explains how our diets might need to change depending on what stage of life we’re in.

The Conversation’s Phoebe Roth started by asking: what should kids be eating and how much should parents worry about children eating vegetables?

An edited transcript is below.

Everything you need to know about how to listen to a podcast is here.

Additional audio credits

Kindergarten by Unkle Ho, from Elefant Traks.

Podcast episode recorded by Phoebe Roth and edited by Sophia Morris.

Shutterstock

Clare Collins: Parents worry so much about what children eat. But the rule of thumb is if they’re growing well, then you don’t need to worry. They are eating enough food.

And the way you know if they’re growing well is: if you take their baby book or you have a growth chart on your wall and you plot their height and weight regularly, you’ll be able to see if they’re following one of the lines on the growth chart. And that’s the best indicator.

The other thing that’s worth remembering is that a well child won’t starve themselves. But for children, their appetite is more variable than an adult. With us, we go, “Well, 12 o'clock, better eat lunch,” or “Oh, I’m awake, better have breakfast now because I’m going to be busy at work later.” But for children, they’re much more responsive to their internal cues.

And the younger the child, the more variable their appetite. So a typical thing is, a two or three year old might eat a massive breakfast and tomorrow they don’t eat any. At daycare, they might eat a huge lunch or none at all. And then the same thing happens at dinner. So if your child’s in daycare, you might want to look in the book or ask the staff, did they eat afternoon tea and lunch today? And that’ll give you a little bit of a guide as to whether you should be encouraging them to eat a little bit more dinner or just go, well, they had just had a massive afternoon tea, so they’re not really going to be hungry.

The other thing with children around the evening meal is that they often run out of steam by the end of the day. So having the evening meal as early as is practical. And for a young child, that may mean they’re having their dinner at five o'clock. And then what they eat at the family meal time is an optional extra. Because if you make them wait till 6 or 7pm, they’re over it and dinner becomes a nightmare.

The other thing that we know about kids, in terms of should we worry about them not eating vegetables, is we’ve actually done some research on this. And we found for kids around the age of three, the biggest predictor of their vegetable intake was not what mum had eaten in pregnancy. It was actually what the parents were eating now. So if you really want your children to eat heaps of veggies, it’s monkey-see-monkey-do, then that means we’ve got to look at how much we love our broccoli, mum and dad. And then that will make a big difference.

The other factor that comes into vegetable intake is genetics. And about 25% of people are what are called “super tasters”. That means they have got extra taste buds. And I wrote an article about this on The Conversation, actually. And so they taste things like the brassicas family – so Brussels sprouts, cauliflower – they taste it as more bitter than people who were either, not super tasters or, you know, have less taste buds. But more good news: even if you’re a super taster, if you don’t give up and you have repeated exposure, you even overcome that. So there’s no excuse for not liking your cauliflower.

Phoebe Roth: That’s really interesting. I had no idea about a lot of that. So you started to touch on my next question, but I wonder if there are any other tips you’ve got. I was going to ask, what does the evidence say works for developing healthy eating habits during childhood or for kids if you’re worried perhaps they’re not eating as well as they should be.

Clare Collins: The key thing for developing healthy eating habits in childhood is not giving up and trying not to stress. So really accepting there is variability. Studies have been done on toddler intake and shown that over 24 hours they pretty much eat about the same total energy intake. But if you look meal to meal, hugely variable, like I mentioned.

The other key time when I think parents, you know, the food wars can start around 18 months and then people go, you know, “the terrible twos, they just never eat anything!” Well, if you want to avoid the food wars, then around 18 months, just step back a little bit and observe how much food is your child usually eating, because up until 18 months, babies have tripled their birth weight. So, you know, born around, say you’re around three kilos, well around six months you’ll be six kilos and around 18 months you’ll be nine kilos. Now, if in the next 18 months you tripled your birth weight again, what would that be? Nine, 18, 36 kilos. Around that. So around 18 months, depending on a child’s activity, they can actually go through a period of time where their energy needs are relatively less and you are going “No, last month they’d eat a whole punnet of blueberries!” and then you may start trying to force feed them. That’s where the beginnings of the food wars can start. So, trusting, like I said, that a well child will not starve themselves.

It can be different if the child has medical requirements and need for a therapeutic diet. That’s a whole separate kettle of fish and you’d be needing to talk to your GP, maybe be referred to a dietitian for specific problems or if there’s actual feeding problems, a speech pathologist.

So for the average child, it is about exposure, letting them feed themselves, not force feeding them and rewarding the behaviour that you want to see. So picture this: dinner time at the table. One child chasing those veggies around the plate with a fork and the other child eating up the foods that they’re really hungry for. If you focus on the child doing the “right thing” – you know, “I love the way, Jodi, you’re eating that broccoli and carrots,” rather than, “hey, Sammy, you’re going to sit there til every pea has disappeared off your plate” – well, then you’re reinforcing that vegetables are disgusting. So if you focus on the behaviours you want to see, then the other children start to recognise that, “oh, I only get attention if I’m doing the ‘right thing’. ” So reward the behaviour you want to see.

Most of the dinner is consumed in 20 minutes. So don’t make the meals drawn out. And for kids with a smaller appetite, having healthy snacks will make up for what’s not eaten within 20 minutes.

Phoebe Roth: Okay, great. And today we’re discussing, obviously, the Australian Dietary Guidelines and sort of adapting diet at each stage of life. And so I wanted to know at which of life’s different stages might our dietary needs change? We’ve now talked about kids, but what about, say, for pregnant women, women going through menopause and any others?

Clare Collins: Okay. For boys and girls, their dietary needs stay about the same until adolescence. And then that’s the first time the next alarm bells ring. Once girls start menstruating then their iron requirements are much, much greater. Boys, if they’re super active and they have a big increase in lean body mass – so it’s kind of like, you know, if you go from a little car to a big car, you need a lot more fuel – so for boys, all of a sudden they’re eating a lot more food. And meeting those nutritional requirements of adolescence is important because adolescence is also the time when teenagers typically experiment with different types of diets, you know, so they might be on a vegetarian diet or a vegan diet. So just keeping an eye on that. The key nutrients are iron – and you can get that from vegetarian foods and great articles on The Conversation about that, by the way.

And there’s also articles on The Conversation about adolescents and another typical issue that arises at adolescence, where parents are going “I wonder if this is a dietary problem” is diet and acne. And I’ve actually written on that for The Conversation.

And your nutrient needs for women change again during pregnancy and breastfeeding. The growing baby is a pretty good sponge. So it’s really the mum’s nutritional status that’s most at risk and the baby will be doing its best to grow with whatever fuel’s available. But to optimise the baby’s growth and development, you do want to have a nutritious dietary pattern. But you don’t need as much extra food and nutrients as you think. Basically, it’s equivalent to an extra tub of yoghurt and a salad sandwich to meet your extra requirements. But some diet-related problems do kick off in pregnancy like heartburn or developing constipation. And, you know, pregnant women and this happened to me as well, during pregnancy, go, hey, how come this is happening? Well, during pregnancy, there are hormonal changes to essentially slow down your transit time in your gut to give your body the best chance of getting any nutrients out of the food so to support the pregnancy.

And so eating healthily in pregnancy is really important, but you may need a boost in your dietary fibre intake. And one of the articles I’ve written for The Conversation is on how to manage constipation. And there’s a whole hierarchy of nutrition things you can do. And beyond that, then you really do need to mention it to your obstetrician or your GP in case you need some other type of like medicinal help. And then it’s got to make sure it’s something that’s safe for pregnancy. And you do need to talk to them about that.

Phoebe Roth: Sure. Are there any other life stages where you might need to think about changing your diet? What if, say, you develop a particular health condition?

Clare Collins: If you develop a particular health condition, then absolutely. The most common diet-related health conditions in Australia is type 2 diabetes. And some people are now being diagnosed with pre-diabetes, which is like an alarm bell and gives you a chance to change your dietary patterns and your lifestyle behaviours like physical activity so that you don’t go on to develop type 2 diabetes. And then the other one is heart disease. Both of those have dietary components.

So for type 2 diabetes, you’re likely to moderate the type and amount of carbohydrate. And for heart disease, there’s a whole range of bioactive foods that you can boost your intake of – whole grains, vegetables and fruit, reducing your saturated fat intake. And, you know, you can find articles about all of those things on The Conversation.

But if you read those and you go, oh, wow, it’s way more complex than I thought or I really would like some personalised advice, then ask your GP to refer you to an Accredited Practising Dietitian and get a personalised plan.

Phoebe Roth: Yeah, absolutely. And the other one is menopause. I know you’re writing an article for us coming up on menopause and whether there are specific things you need to keep in mind regarding your diet.

Clare Collins: Menopause is really unfair because one of my colleagues, Lauren Williams, who’s co-authoring the article and she’s from Griffith University up there on the Gold Coast, is her whole PhD research was on this topic and she studied the Australian Longitudinal Study of Women’s Health and followed the women as they transitioned through menopause. And the average weight gain is about two and a half kilos.

But even that is not the most unfair aspect of menopause. What she discovered is that there’s no discount, if you like, on gaining weight, if you lived a healthy lifestyle already, that all women are prone to weight gain during menopause. And it’s a combination of the hormonal changes amplified by life changes. And some of those life changes are that for most women, the physical work actually reduces at that time. You know, the house might be less people living in your house and you don’t have to do as much housework.

For many women, you have more disposable income. So you actually can go out a little bit more, spend more money on eating out. And the other thing is it’s a life stage where alcohol intake increases in women. You know, the perfect storm. You know, you had this lovely, healthy lifestyle and then you gained weight.

But what she also found, which is the important message, is that during that menopausal transition, women who changed something, they went, “Right. I’m going to beat this weight gain.” And they decided to eat more vegetables or develop new, healthier recipes or walk a lot more. They did not gain that average two point, 2.5-ish kilos.

As much as I really think that sucks that we gain weight during menopause, I’m really pleased to know that it’s not inevitable, but it’s kind of like, you know, it’s like having to do a spring clean on your life stage patterns, on your dietary patterns and on your physical activity. And you can get through menopause in a healthy weight and with a healthy lifestyle and be healthier. But we have to be on guard. So unfair.

Phoebe Roth: So in the healthy eating side of things, would that just be sort of following the Australian Dietary Guidelines?

Clare Collins: Well, yes, but we need to make a little note of caution about the Dietary Guidelines. And that is not many people eat like the Australian Dietary Guidelines. In fact, the Australian Institute of Health and Welfare modelled what would happen if people did eat five serves of vegetables and two serves of fruit and had their whole grains and used reduced fat dairy and, you know, chose the leanest forms of protein.

They model that if everyone in Australia tomorrow started eating like the recommendations found in the Australian Dietary Guidelines, that heart disease rates would drop by 62% and that diabetes rates would drop by – type 2 diabetes rates, I should say – would drop by around 40%. That’s not going to happen. People aren’t going to do that. And we know that only 3 out of 100 Australians eat five serves of vegetables a day.

So, yes, definitely eat more like the Australian Guide to Healthy Eating and the Australian Dietary Guidelines, but a good place you can start is the Healthy Eating Quiz. This is a short quiz that takes less than 10 minutes to do. It’s free and it’s online. It rates your dietary patterns compared to recommendations in the Australian Dietary Guidelines. And that now links to a really fun website – we think it’s fun anyway because we invented it – called No Money, No Time. It’s got recipe recommendations to match with your Healthy Eating Quiz report.

We’ve set up some fun filters on there. So if you’ve only got a basic kitchen and you’ve got a microwave and just one pot, you can filter it for recipes matching your kitchen equipment. And we also added this other filter that allows you to say what your healthy lifestyle goals are. And we’ve catered for all ages on that. Some people told us their goal was to have glowing skin. And some people said, I want to do better in my sport. And some people have said I want to manage my weight. So you can further tailor the recipes for that. So No Money, No Time and the Healthy Eating Quiz. And that’s our way of trying to help Australians eat a little bit more healthy and feel better and have their health improve as well.

Phoebe Roth: I am already keen to jump on that straight after this and give it a try. Great. So the Dietary Guidelines, would you say they’re a really good resource and reference point, but possibly not a one size fits all approach?

Clare Collins: Absolutely. And there are some resources on the government websites called Eat for Health, and there are some resources on that. And they are designed for the predominantly healthy Australian population while recognising that overweight and obesity are relatively common and that people are commonly seeking extra advice for things like type 2 diabetes and heart disease. There’s certainly a good first place to stop. But as I mentioned, you may need extra specialised help if you have some of those common chronic diseases. And a good place to start to find out is with a health check up with your general practitioner who can do a heart health check and check your blood pressure. And you know, if you don’t have scales at home, they can do a check on your weight. But more important than that is checking on your blood to see what your cholesterol level is and whether your blood sugar levels are high, indicating you’re at a higher risk for type 2 diabetes.

Phoebe Roth: So what do people need to consider to ensure they’re following the right diet for their individual circumstances or for their stage of life?

Clare Collins: I think the key thing, when it comes to diet-related health or nutrition-related health is knowing what your risk factors are for these chronic conditions. And really to know those, you do need to check in with a health professional, with your general practitioner. You might be a lucky person who has the genes that mean you have wonderful blood sugar levels and you have wonderful cholesterol levels and your blood pressure’s great. Then that would essentially mean that you’re doing the right things for your genes and for your body. But a check-up with your GP is usually a chance to see, you know, what does need to be tweaked in my diet? One of the things about high blood pressure is that it’s really common, but there’s absolutely no signs or symptoms. So until you get it checked by your GP, you wouldn’t even know.

Phoebe Roth: What about for older people? What sort of things do they need to consider about diet?

Clare Collins: Once you start approaching 75 and above, then it’s interesting that your nutrition requirements and your dietary requirements start to shift a little bit. Once you get older, the focus moves to trying not to lose your muscle tissue. There’s a word for that malnutrition of older age and it’s called sarcopenia. And it’s really important. And so as you age to protect your body from sarcopenia, your protein requirements actually start to go up.

And people have this image of, “Oh, you know older people. They just need a cup of tea and a piece of toast.” Well, they actually don’t. They might need their coffee made on milk or they might need a nutritional supplement if their appetite’s really poor. And this is another time where you may need specialised nutrition advice. If there’s any underlying medical conditions or if the older people in your family are in a nursing home, you may need to talk to the nursing home staff about whether they’re meeting their nutritional requirements or not.

As you age physical activity and because your muscle mass decreases, your total energy intake reduces. And it’s a little bit like going from the big car down to the smaller car. You still need the same amounts of vitamins and minerals and things we call phytonutrients. You know, they’re not a vitamin or they’re not a mineral, but they help your body run better. You still need the same amount of them, but you need them in less energy. So there’s like less room for error. So the tea and toast isn’t adequate, you know, for grandma or granddad, for the older person. They’re having nutritious and nutrient dense foods.

So, you know, vegetable soup, so to put all the vegetables in, in the right texture that looks appealing is really important. The other thing as you get older is that your taste buds change. You can have less. Some of your taste buds start to decline. And so flavouring food more and to the way, you know, Nanna or Grandpa like it rather than the way you like it is really important. So it can be a life stage where for people, if they think, “Gee, food just doesn’t taste as good anymore, then trying out what herbs, spices and flavourings they like and using those to replace salt.

Because as you age you’re more prone to high blood pressure and you’re also more prone to developing diabetes. So nutrition remains important right through your life. And it’s a really important part of our social lives.

So I think, you know, if I had one final message, it’s: no matter what you do or how busy you are, still finding that time to cook, prepare and eat with other people is a really important way of preserving your own family’s food culture and looking after the nutrition-related health and the social well-being of everyone in your family.

Phoebe Roth: And the last question I have, I wonder if – it goes into all ages, for anyone that’s trying to eat healthy and follow a healthy diet – where do superfoods fit in? I know that there may not be one answer to fit all, but I think that that’s kind of a question people grapple with it when the next fad is right in front of them. And you know, what do they do? Should they eat this? Should they go out and buy it?

Clare Collins: Fad diets are just so ongoing and regular that we often write articles for The Conversation about them. But you know, my thing about superfoods is that there are super foods, there’s heaps of them and they’re actually all in the supermarket.

And when you walk in the supermarket – this is one way supermarket design does try and help us eat healthy – you walk smack bang into the super food section and they’re right there. They don’t have packages. They don’t have labels. But it’s that wide variety of vegetables and fruit. And I think if there was one important thing to remember, when you go to the supermarket every week when you went to the supermarket or you enter a market, look at those vegetable and fruits and which one has not been in your trolley, you know, in the last couple of weeks? And invite them in. Some of the research that we’ve done shows that the variety of vegetables and fruit, but particularly the variety of vegetables, predicts your long term health care costs.

And we’ve shown that in a research study over 15 years on the Australian Longitudinal study on Women’s Health. And lots of the research we’ve been doing is showing that the variety of those foods that belong to the Australian Guide to Healthy Eating in the Australian Dietary Guidelines, that it’s actually those nutrient-rich foods that predict your nutrient intake and then decide whether you’re on a path for health or you’re not on a path for health. You’re on a path for poor health.

So going for variety in your whole grains, your vegetables, your fruits, your sources of protein, which includes meat, poultry, fish and then all the wonderful vegetarian sources and whole grains. Collectively, those things make up a healthy diet pattern. They make up you when you eat them. And then that determines whether you’re going to be healthy or less healthy.

Phoebe Roth: Is there anything else you want to talk about that we didn’t touch on?

Clare Collins: The only thing is I hope people don’t feel alone when it comes to nutrition. Go and have a look at No Money, No Time. Not only have we loaded that website up with lots of recipes, we’ve also loaded up with lots of information, hacks and myths. We’ve linked a lot of The Conversation articles to it. And then the other place to go for good information is go to The Conversation and type in nutrition in the search bar. And you’ll see lots of the articles that myself, my team and lots of other academics from other universities around Australia have written on food and nutrition.

Phoebe Roth: Thank you so much, Clare, for joining us on Trust Me, I’m An Expert today. It’s been great talking to you again.

Clare Collins: Thank you. It’s my absolute pleasure.

What does the COVID-19 pandemic sound like?

For this episode, Dallas Rogers – a senior lecturer in the School of Architecture, Design and Planning at the University of Sydney – asked academic colleagues from all over the world to open up the voice recorder on their phones and record a two minute report from the field about their city.

Many of those who responded to the call are struggling, just like us, to make sense of their experience in the COVID-19 city.

The resulting stories reflect on hygiene, disease, quarantine, social control and the urban environment from cities around the world.

If you want to hear all the stories in full, you can find them here, and read more about the project here.

Roger Keil (@rkeil), Professor at York University

Jason Byrne (@CityByrne), Professor at the University of Tasmania

Kurt Iveson (@kurtiveson), Associate Professor at the University of Sydney

Tanja Dreher (@TanjaDreher), Associate Professor at the University of NSW

Carolyn Whitzman (@CWhitzman), Professor and Bank of Montreal Women’s Studies Scholar at the University of Ottawa

Tooran Alizadeh (@DrTooran), Associate Professor at the University of Sydney

Eugene McCann (@EJMcCann), Professor at Simon Fraser University

Beth Watts (@BethWatts494), a Senior Research Fellow at Heriot-Watt University

Amanda Kass (@Amanda_Kass), PhD candidate at the University of Illinois at Chicago

Elle Davidson, Aboriginal Planning Lecturer at the University of Sydney

Creighton Connolly (@Creighton88), Senior Lecturer at the University of Lincoln

Kelly Dombroski (@DombroskiKelly), Senior Lecturer at the University of Canterbury

Kate Murray (@katiemelbourne), Connected Cities Lab at the University of Melbourne

Em Dale (@carnivoresetal), at Oxford University

Matt Novacevski (@places_calling), PhD candidate at the University of Melbourne

Mirjam Büdenbender (@MBuedenbender), advisor to the chair of the social-democratic parliamentary group in Berlin

Natalie Osborne (@DrNatOsborne), Lecturer at Griffith University

Ash Alam (@urbanmargin), Lecturer at University of Otago

Cameron Murray (@DrCameronMurray), Post-doctoral fellow at the University of Sydney

Deepti Prasad (@Deepti_Prasad_), PhD candidate at the University of Sydney

Madeleine Pill (@pillmad), Senior Lecturer at the University of Sheffield

Matt Wade, (@geminidluxe), Post-doctoral Fellow at the National University of Singapore is with Renae Johnson, an independent artist, in Singapore

Susan Caldis (@SusanCaldis), PhD candidate at Macquarie University

Paul Maginn (@Planographer), Associate Professor at the University of Western Australia

Crop circles by Craft Case, Inspri8ion by Pulsed, The city below by Marten Moses, Someone else’s memories by So Vea. https://www.epidemicsound.com/

Theme beats by Unkle Ho from Elefant Traks.

Project coordinated by Dallas Rogers.

Audio edited by Miles P. Herbert, with additional audio editing by Wes Mountain.

AAP/EPA/ANDY RAIN

What do you need to know about COVID-19 and coronavirus? We asked our readers for their top questions and sought answers from two of Australia’s leading virus and vaccine experts.

Today’s podcast episode features Professor Michael Wallach and Dr Lisa Sedger – both from the School of Life Sciences at the University of Technology, Sydney – answering questions from you, our readers. An edited transcript is below.

And if you have any questions yourself, please add them to the comments below.

Everything you need to know about how to listen to a podcast is here.

Sunanda Creagh: Hi, I’m Sunanda Creagh. I’m the Digital Storytelling editor at The Conversation, and I’m here today with two of Australia’s leading researchers on viruses and vaccines.

Lisa Sedger: Hi, my name’s Lisa Sedger. I’m an academic virologist at the University of Technology Sydney. And I do research on novel anti-viral agents and teach virology.

Michael Wallach: I’m Professor Michael Wallach, the Associate Head of School for the School of Life Science (at the University of Technology Sydney) and my expertise in the area of development of vaccines.

Sunanda Creagh: And today, we’re asking these researchers to answer questions about coronavirus and COVID-19 from you guys, our readers and our audience. We’re going to kick it off with Dr. Sedger. Adam would like to know: how long can this virus survive in various temperatures on a surface, say, a door handle or a counter at a public place?

Lisa Sedger: Oh, well, that’s an interesting question, because we hear a variety of answers. Some people say that these types of envelope viruses can exist for two to three days, but it really depends on the amount of moisture and humidity and what happens on that surface afterwards, whether it’s wiped off or something. So potentially for longer than that, potentially up to a week. But with cleaning and disinfectants, etc, not very long.

Sunanda Creagh: And what’s an envelope virus?

Lisa Sedger: Well, viruses are basically nucleic acid. So DNA like is in all of the cells in our body or RNA. And then they have a protein coat and then outside of that they have an envelope that’s made of lipids. So it’s just an outer layer of the virus. And if it’s made of lipids, you can imagine any kind of detergent like when you’re doing your dishes, disrupts all the lipids in the fat. That’s how you get all the grease off your plates. Right? So any detergent like that will disrupt the envelope of the virus and make it non-infective. So cleaning surfaces is a good way to try and eliminate an infective virus particle from, for example, door handles, surfaces, et cetera.

Sunanda Creagh: And Professor Wallach, Paul would like to know: should people cancel travel plans given that this virus is already here? Does travelling make the spread worse? And that’s international travel or domestic travel.

Michael Wallach: So this question has come up to many different governments from around the world who’ve reacted very differently. Australia’s been very strategic in banning travel to certain places. And of course, those places you would not want to travel to at the time when there’s an outbreak like China, Italy, Iran, etc.. I was also asked the question on ABC Tasmania: should the Tasmanians restrict domestic travel to Tasmania? At the time, they had a single case. And I said to them, if you have one case, you most likely have more. You will not prevent the entry of the virus into Tasmania. But what restricting travel can do is restrict the number of people who are seeding that area with virus and make it more manageable. So it’s a question of timing. As I was saying to you earlier, the cost-benefit of closing off travel has to be weighed very carefully because the economic impacts are very great. So I think it’s a case by case basis. Ultimately, the planet is now seeded. And we’re moving into the stage of exponential growth and that it will affect travel very severely, where in all likelihood, travel will be very much curtailed now.

Sunanda Creagh: And this question’s from our reader, David. He wants to know: with the flu killing more people each year than coronavirus and mostly the same demographic, why is this outbreak receiving so much attention? Can’t we just catch the flu just as easily without cancelling events and travel plans?

Lisa Sedger: Yes, and I understand the question. Flu exists. We get it seasonally every year and then we get pandemic flu. And yes, people do die from influenza. I think it was 16,000 people in the US died last US winter. But the issue with this virus is that we don’t yet know how to treat it particularly well. We’re trialling anti-viral drugs in China at the very moment. There’s clinical trials on experimental drugs. There’s drugs that doctors are using. But until that data comes in and we actually know what regime of anti-viral drugs (are best) to use, then we don’t really yet know how to treat it with anti-viral drugs. The other thing is with flu, we have a vaccine. People can take the vaccine. Somebody gets sick in their family, the other family members can take the vaccine and prevent the spread of the virus. So the difference is with flu, we have ways to control it. We know about the disease. We know how it presents. This virus, we’re still understanding the clinical presentation and in different cohorts. So different age groups, different countries, different situations, we’re still understanding the symptoms. And we don’t yet fully know how to control it by antivirals. And we don’t have a vaccine yet.

Michael Wallach: Can I just add to that a bit? I think one of the reasons we’re being so careful is when it broke and Wuhan, at the beginning the mortality rate was extremely high. And with related viruses like SARS, and MERS that went as high as 35%, whereas flu mortality rates is usually around 0.1%. So it was that very high mortality rate that gave a real shock. Had it continued, it would have been devastating. We’re very fortunate that now we see it dropping down to the 2 to 3% level and some say much lower.

Lisa Sedger: And we also know now that some people get COVID, have very minimal symptoms and almost don’t even know that they’ve been sick. So I think that fear and anxiety, in that sense, is lowering.

Sunanda Creagh: And Molly wants to know: how far off is a vaccine?

Michael Wallach: So, we are working on vaccines in Australia. The group in Melbourne was the first to be able to isolate and grow the virus. And I’ve been in touch with them, in fact, this morning. We’re working collaboratively nationally as well as internationally, collaborating with people at Stanford Medical School who through Stanford, in collaborations we have with them, we have worldwide about 15 vaccine projects going, plus all sorts of industry companies are aiming to make vaccines. In fact, one company in Israel early on announced that they believe that they can get to a vaccine within a few weeks. The problem with the vaccine is you may produce it even quickly, but it’s testing it and making sure that it’s actually going to help. There’s a fear, with COVID-19, that if it is not formulated correctly, to make a long story short, it can actually exacerbate the disease. So everyone has to take it slowly and carefully so that we don’t actually cause more problems than we currently have. But I’m optimistic and believe that we’ll get there. The WHO declared it would take 18 months. I would like to present a more optimistic view, not based on anything that substantial, but I think we can do better than that. And it is a great learning curve for the next time this happens.

Lisa Sedger: Can I make a comment on that, too? Recently, we’ve just seen Africa experience a very significant outbreak of Ebola virus, and there’s been an experimental vaccine that’s been administered that has largely controlled that outbreak. I think the people working in vaccines and the people who do the safety and efficacy studies, we’ve learnt a lot from how to administer vaccines, how to get the data we need to show safety more quickly than we might have in the past. So in the sense we’ve learnt, we’re learning lessons constantly from viral outbreaks. It might not be the same virus, might not be the same country, even the same continent. But we’re learning how to do these things more efficiently and more quickly. And always the issue is weighing up safety versus the ethics of the need to administer all get it, get the drug out there as quickly as possible.

Sunanda Creagh: This reader asks: isn’t lining up at fever clinics for tests just going to spread it even more?

Michael Wallach: So for sure, the way in which people are processed at clinics is crucial and the minimal distance you should keep from a person who’s infected is, according again to the WHO, is one metre. So the clinics have to ensure that spread is minimised, not only spread between people waiting in line, but to the health workers themselves. We’ve had real problems for health workers in China. Several died. And we face that problem here. One of the things we have to do is ensure that we protect our health workers because otherwise they’re not going to want to go in and actually see the patients. Unfortunately, masks alone do not work. We can’t rely on them. So it’s a problem. In Israel, for example, testing for COVID-19, takes place in one’s home. An ambulance pulls up and takes the swab and then takes it to the lab. That actually would be the ideal approach. True, the ambulance services in Israel now are swamped and having great difficulty in coping. But as much as we can keep people separated from each other when they’re infected, it’s crucial for the success of any campaign.

Sunanda Creagh: And these questions from Jake. He wants to know for people like myself living in Victoria. How likely is it that we can catch the virus and is hand-washing really the only thing we can be doing to protect ourselves?

Lisa Sedger: I think we now know that the virus is definitely in Australia. If you go to the New South Wales or Victorian Health government websites, you can see them update the statistics daily, even less than a day so that the truth is it’s here and it’s probably in more people than we realise because we haven’t tested as many people and we now realise some people are asymptomatic or don’t show classic flu like symptoms. So it’s here and you can’t say that you’re not going to get sick. Alright? That’s the first thing to say. The second thing is, though, we can minimise what we do. Okay. So we can wash our hands constantly. We can try not to touch our face, our eyes, our ears, our nose. We’ve learned, for example, even how do you dispose of a tissue when you sneeze or cough or, you know, sneeze into your elbow? So it’s just about common sense. This is what I think. It’s no different really than protecting yourself from any respiratory virus infection. So seasonal flu or even a pandemic flu.

Sunanda Creagh: And how do you dispose of a tissue safely?

Lisa Sedger: Well, I guess you fold it in and then you put - you don’t touch it, you don’t put it up your sleeve, OK? - you put it in the garbage bin and wash your hands afterwards.

Sunanda Creagh: Michael would like to know: what can we learn from other countries that are handling this well? He says basically South Korea, as far as I can tell.

Michael Wallach: So the country that handled this outbreak the best so far has been Taiwan. The Taiwanese have been amazing in the sense that after the pandemic commenced in China, many Taiwanese returned to Taiwan. And you would have expected they’d seed that island very strongly and it would be a major outbreak. They were ready before the pandemic commenced. And that was largely because they went through a SARS outbreak. Previously, they had in place all the testing, all the people. They have the best health system in the world. And they kept the numbers down to 45 cases during a period when in China it was going into the tens of thousands. And they should be commended on that. It’s quite amazing the way they did that. The issue now in Taiwan, which concerns them, is in the end, that’s a great start. But their population now is unexposed and susceptible. So how do you release them from this sort of quarantine situation? That is the next phase. And that’s what we’re looking to see how that works, because same in Wuhan. The minute you put everyone back out to work and in the street, will there be a second wave? Most virologists, I think, would expect there will be a major second wave, third wave and maybe continued into the future. So we have to continue with our preparedness and with the hope that the vaccine will come into effect sooner rather than later. And then bringing the quarantine approach, enabling that peak of viral infection to occur when the vaccine is available. That would be the goal.

Lisa Sedger: If I could just add one point there. When you look at the number of cases on a per day basis in Wuhan, it was escalating very quickly. And then they brought in their very strict quarantine and self-isolation. But the cases continued to increase until a point where it started to look like it was under control and going down. And that was after two weeks. So quarantine only works until after the quarantine period, because only after that will you see the effect. So I would argue there’s two factors for why isolation worked in Wuhan: One was you limited the spread through the self-isolation and imposed quarantine, but at the same time, the number of people who are infected and asymptomatic were building their own immunity. The number of people who were infected and sick but who survived, one would imagine, have a robust immune response to that virus. So at the same time as limiting spread, you have also slowly built or actually quite quickly built a community with much higher levels of what we call herd immunity. So this second outbreak may come, but it may be considerably less significant.

Michael Wallach: In fact, that the areas where there are the major outbreaks maybe have better herd immunity than places where you keep it down to nothing. So it works both ways.

Sunanda Creagh: And Jane would like to know: when do we stop testing for this disease and basically just assume that everybody with the sniffles has it?

Michael Wallach: So first of all, the major symptoms are not sniffles, they are fever and coughing and shortness of breath. It’s the sniffles, though, that causes it to be spreadable more easily. That’s a good question: what the health authorities will decide to do at various stages of this pandemic. We’re now at what I would consider the early seeding phase. The world is now seeded with virus and different countries were going through exponential phases like described in Wuhan at different times. And how do they handle that will be a crucial question. I’ve seen all the different approaches from US, Israel, Iran. I think that a mixture of very strategic quarantine with travel restrictions, with bringing in other types of… certainly health authorities will need to control the number of beds that are being occupied. For example, again, in Israel, they just went over their bed limits, so patients are starting to be treated at home. So at some point, I think depending on how the epidemic goes, if we can keep it under control, we can keep the testing going. We can keep control. If the exponential rise is too fast, we will lose control and the testing will become meaningless. So the hope is that things will be sorted and I think Australia has the opportunity to do really well and big decisions have to be made now.

Lisa Sedger: There’s already a paper just this week published in The Lancet that profiles survivors versus those who have succumbed from the infection. And we’re starting to learn what some of those factors are. So as as clinicians can better predict who are likely to be the more seriously ill people, they can better predict who should go to hospital for treatment, and as Michael has said, who are better actually just treated at home.

Sunanda Creagh: And Dr. Sedger, Kardia would like to know: how does this virus respond to cold or warm temperatures? Is it like the flu, which thrives in cold weather?

Lisa Sedger: I have heard so many different things about this. I will be completely honest and say I’m not certain that we really know. What we know is when this high humidity viruses can exist for longer because they don’t dry out. So that envelope we talked about is less likely to be dried out. And once that’s dried out, the virus is less infective. It’s not actually infective at all if it’s disrupted that envelope. But whether it likes cold temperatures, high temperatures, we think it’s not a warm temperature virus. We think it’s more a cold temperature virus. China’s just been going through their winter. Maybe one of the reasons it’s been big in Italy is they’ve just had winter. We also think the coexistence of seasonal flu in Italy at the same time is probably one of the factors that’s made it more severe. So, yeah, look, different circumstances in different countries, different climates. It’s not just about climate, though. It’s about susceptibility of various populations. Therefore, it’s a hard question to answer (at the moment).

Michael Wallach: Look, I would say in working in infectious diseases for many years, it’s a very difficult thing to predict. Remember with, it doesn’t matter which disease I was working on, everyone said it can’t transmit in dry climates. And it transmitted beautifully in the desert. And you think everything’s totally dry and it still transmits and vice versa.

Lisa Sedger: Well, you’ve got MERS is another coronavirus, which is your Middle Eastern Respiratory Syndrome, and that’s in the desert climates. So that’s why I wanted to hedge my bets on my answer.

Sunanda Creagh: And Professor Wallach, this reader wants to know: once you’ve recovered from coronavirus, can you just go back to your normal, non-isolating life?

Michael Wallach: So the current understanding, according to colleagues also in the U.S., is if you go through one infection, you’re probably rendered immune against re-infection. There have been reports of cases of people getting re-infected. But the opinion that I heard so far is that it’s probably recurrence of the same infection that probably went down in terms of clinical symptoms. But the virus remained that just came back up. It happens with the flu all the time. The question is, what should be your behaviour after you go through a bout? I guess I would still be careful, which Lisa can maybe add to, it could be that the virus will continue to mutate. Although again, I fortunately heard this morning that they’re not that worried about this virus mutating at the rate that flu does. And we’re hopeful that we will develop herd immunity. People have gone through it then will be fairly safe unless, you have some immune disorder. And then it will become part of our environment just like flu is.

Sunanda Creagh: And here’s a question from me. It seems like there’s two camps. There’s the people who genuinely really concerned, quite worried about the situation. We see that in the panic buying. And then there’s the other camp of people who are saying it’s all been blown up. It’s all hype. We don’t really need to worry about it. It’s too early to panic. And I just wondered, how do you reconcile those two views out there in the community?

Michael Wallach: So early on in this outbreak, when I was interviewed also on the ABC and speaking to other groups, I took a very low panic view, maybe because I’ve been thinking about a pandemic for many years. And for me, it was always not a question of if, but when. I actually look at this, in a way, in a positive sense. We’re facing a pandemic that, yeah, as terrible as it is, is nothing in comparison to what could be if it’s a pandemic flu. For example, we experienced the Spanish flu in 1918, which killed somewhere between 20 to 50 million people. So the order of magnitude of mortality right now is extremely low compared to other potential pandemics. If you take China out of the equation, we’re at about 1500 people who died worldwide. That’s not to say we shouldn’t show great respect for the value of their lives. It’s mainly very elderly people with complicating illnesses and probably would have had the same effect if they were infected by flu. So my take on this whole thing is we all have to stay calm. We all have to accept the fact that this is part of nature. These viruses are out there all the time. We know them. I can detect now flu viruses in wildlife, birds that are coming into this country now, that can mutate and start affecting humans. So we have to be prepared. We have to face up to them, together in a collaborative way, in a scientific and professional way. And we could win. If we panic and react the way the market is, for example, of course, that’s that’s an improper way to react. Rather, this is part of being, of our biology. Viruses exist that can hurt us and they will always exist.

Lisa Sedger: Yeah. Look, I think there are a few factors that we can really learn from. So one is to work out where these viruses come from. And a lot of these RNA viruses exist in bats. They seem to be transmitted into wild animals through bat droppings. And I think one of the lessons we, the world all over, might need to learn is how we deal with the marketing and selling of wild animals that are then used for foods. That may then prevent these viruses from getting into the human population. So I think there are lessons to be learned, number one. But Michael, I would disagree with you in one sense “that it is maybe not as bad as pandemic flu”, on the other hand: we do have vaccines for flu, we do have anti-virals. And we have a whole world that has various levels of immunity to flu and different strains of flu. Whereas this virus is entering into a naive (non)-immune population. And that’s what’s so significant to start with. It may be that as our immunity at a population level increases, as a disease this will become far less significant. But the first outbreak of it in a naive, (non)-immune, (and a) “naive population” will always have the highest level of morbidity and mortality. And that’s where we have learned from other diseases like Ebola. As I mentioned, what we already know about flu, how we already control flu and the development of new and novel antiviral agents will be just as effective and important, I believe, as will the development of vaccines. So I think there’s a lot to learn to prevent this or limit, I should say, to limit these the severity of the outbreak and maybe even prevent it from happening again. As I say, if we stop trapping wild animals and eating them, we might prevent the outbreak of some of these type of RNA viruses.

Michael Wallach: So I certainly agree with that. And China is now putting into law a restriction on the sale of wildlife in their markets. What I’m trying to do, and I hope we both agree, is that in proportion to, for example, influenza, even seasonal flu that killed in one year I think up to 600,000 people worldwide, I’m just trying to put things into proportion. To prevent people from panicking. To understand that, yes, this is affecting the elderly. And anyone who is elderly, suffering from heart or respiratory conditions would certainly isolate themselves. So where my wife’s parents live, where they live in a retirement village, they made a decision to close off the entire village. Nobody’s allowed in, as a means of preventing - because they’re an elderly population - people bringing in COVID-19 and infecting that area. And I certainly agree with that sort of strategy.

Sunanda Creagh: And John would like to know: are the death rates likely to be lower in a country like Australia with lower rates of smoking than places such as China, Iran and Indonesia?

Lisa Sedger: Again, I think this is a little bit we have to watch and just wait and see. It’s very hard to predict these things. It was intriguing that some of the highest death rates in China appeared to be men as well as just the elderly. And that might be because there’s a high rate of long term smoking. So almost like an endemic lung pathology within that community that somehow exacerbated the disease. In Australia, we may find that there are different populations that are the most at risk. So we know, for example, the virus uses a receptor to get inside of cells that is a protein present on cardiac tissue. So people with known cardiac conditions may turn out to be at higher risk. And in a non-smoking type country, maybe people with existing heart conditions will turn out to be the most at risk. In America, we might find something quite different. What we might find is it’s more socio-economic. Maybe people without health insurance. Maybe people who are homeless and live on the streets will turn out to be the most affected because they have limited resources to be able to get treatment and they can’t afford treatment. So I think each country will be different. We mentioned earlier Italy has one of the highest fatality rates at the moment. That may be because they actually have a large number of people within their population that are over 65. So it might actually be not that surprising given that demographic. It might also be that they’ve had an outbreak of seasonal flu at the same time. We don’t know whether one type of virus limits the other. It’s quite possible you can get co-infections and that’s where people get the most sick. I think it’s going to pan out in different countries slightly differently. I think it’s a case of watch this space.

Michael Wallach: The other thing, just on the rate of transmission. What they go according to is the people who show up to the clinic. And the results from a study done in China indicate that they may have only picked up 5% of the people that have COVID-19. So it’s about 20-fold more than actually recorded because it’s mild and very little symptoms. The other thing that’s becoming a little disconcerting for scientists is there may be two strains of the virus. And the initial outbreak, as I said, the mortality rate was very high. It could be the virus, in order to transmit, went through a mutation that aided its transmission. And I would hope that would probably occur in pandemic flu. Maybe a little less pathogenic than the original strain was. I was surprised to see at the beginning such high mortality and then how it dropped down. That’s the results also put online by the CDC. And we’re looking and following that.

Lisa Sedger: Yes, viral evolution is a really key topic at the moment. We think RNA viruses and the rate that they mutate is much higher than DNA viruses. And it’s really a factor of how quickly the virus mutates and how quickly a person’s immune response is able to effectively control the virus replication. So the viruses that sometimes persist longer in a community are not necessarily the most virulent. So what we might also be seeing is a population, a group within the population who get a less severe disease, maybe even asymptomatic, but that may, long term, prove to be the bigger - how could I put this? - the bigger population of viruses that exist within that community.

Sunanda Creagh: And Michael would like to know: if I could shrink myself down to microscopic size and watch a virus invade a cell, what would I see?

Lisa Sedger: Well, a virus is not like a bacteria. A bacteria is a entity all of its own, and it can replicate and make another copy of itself and grow on a nutrient source. A virus, however, is sometimes called a non-living entity because outside of a human cell, it can’t replicate. It just exists as an entity. A virus is essentially just a piece of DNA, which is, you know, in the nucleus of every cell. It’s what our chromosomes are made of. So it’s either DNA or RNA surrounded by a protein coat and sometimes it’s also a lipid-based envelope outside of that, again. The virus will somehow encounter a cell. And for respiratory viruses, it’s largely by us inhaling water vapour droplets. They may contain hundreds of viruses. Those viruses then will attach or be exposed to our respiratory epithelium. If the virus can actually bind to the respiratory epithelium cell, then it might get inside. Once inside, it may or may not have the capacity to actually undergo replication, but it has to uncoat from that protein shell. Then the nucleic acid, the DNA or RNA has to make another copy of itself. Then all the genes that are in the virus have to get expressed as proteins. They then reassemble into a new viral particle and then the virus will get out of the cell. Sometimes it lyses (breaks) the cell, sometimes it will just buds out from the cell and leave the cell intact. And that’s what a virus is. That’s why we, some people call them living or non-living because they can only replicate in inside a cell, a host cell.

Michael Wallach: And it’s not like viruses have a will. So if they want to do this, it’s just part of evolution.

Lisa Sedger: Yes, I’m never a favour of the argument you sometimes see people say “it’s warfare, it’s the virus vs. immune system!” But there’s no will involved, it’s just capacity of life to replicate itself.

Sunanda Creagh: And Deidre writes in to say, I heard on the radio today that half the population is likely to get this. And with, say, a 1% death rate, the body count will add up. And I wondered what you thought of that.

Michael Wallach: So there was an announcement actually by Angela Merkel preparing Germany for 70% of the population being infected. Lisa may say the number is lower, I don’t know, until we build up herd immunity. The question of the mortality rate, as I alluded to before, I think based on what again, CDC and WHO are writing, is probably overestimated. Some estimate the mortality rate as being much lower. That’s not to say… every death is a family and has to be looked at and be concerned about. So again, I think and would like to hope that as we develop new vaccines, as we develop drugs, as we develop approaches to quarantine people, test them, keep them at home, isolate them, we’ll get the mortality rate under control. And I’m going to express an optimistic view. This world has amazing capabilities of doing amazing science. And if we apply it and work together, I think we can control this problem.

Lisa Sedger: Yes, absolutely. I would endorse that. And I’d say that the mortality rates at the moment simply reflect who is being tested. And it’s primarily people who are turning up with symptoms. But we’re now beginning to appreciate that there is a large number of people who could be quite asymptomatic, who are never tested. This virus will certainly have infected many more people than will be tested. And if we did have surveillance of every single person being tested, then there’s two questions here: Are you testing for the presence of the virus? If they’ve had virtually no symptoms and not a big illness, you might not find the virus. But if we test for the presence of an immune response to the virus, we would truly know how many people have been infected. And then we could get a true estimate or at least a much closer estimate of what the mortality rate really is. So at the moment, there’s hyperbole.

Sunanda Creagh: And Catherine asks, what is the likelihood of transmission through using a public swimming pool?

Lisa Sedger: I would think quite small because a) the virus would be quite diluted in a swimming pool. Secondly, swimming pools are all treated with chlorine, for example, and chlorine is a very effective anti-viral agent. You’d have to drink a lot of swimming pool water to get the virus.

Michael Wallach: I agree with that.

Sunanda Creagh: Candy would like to know: there are conflicting symptoms lists circulating on Facebook. One says it starts with a dry cough and if your nose is running, it is not COVID-19, which I suspect is incorrect. Can we please have an accurate list?

Michael Wallach: So, again, the major symptoms are, in fact, the cough and shortness of breath and fever. But, it’s not to say it’s not possible that you’ll have also upper respiratory effects. The virus goes into the lung and attaches to the alveolar cells or to the cells that make up our air sacs and that help our breathing. And it has to get there to really cause this disease. So if there’s upper respiratory involvement, which includes sneezing and runny nose, et cetera, it’s probably not the main effect of the virus. Again, I would say if you see that somebody is sneezing and wheezing and and that’s it, it’s probably an allergy, but it does frighten people. I was on the train this morning, and I know if I, God forbid, sneezed the whole train would empty out pretty quickly.

Lisa Sedger: You know, we’re just coming into winter. And actually, it’s a really good question because at the moment, what’s building is a sense of fear. But we must keep in perspective that there will also still be the normal seasonal cases of flu. So just because somebody sneezes or has a sore throat does not mean that they’ve got COVID-19. And we need to make sure, I think it’s really important that we don’t stigmatise people who have symptoms because it may not even be COVID. And we’re all at risk from any respiratory tract infections and already have been for years. That’s not a new thing. We just need to keep things in perspective.

Sunanda Creagh: A question from Karen: can you catch it twice?

Lisa Sedger: Normally, I would have said no, because we imagine that there’s a good immune response that will then provide you protection from re-infection. That’s what our immune system does. But this is a new virus. We don’t yet fully understand how our immune system clears it. We don’t know whether virus can remain for a longer period of time. I would would say, though, that there are only a few cases of people who have been treated, appear to have recovered, they’ve gone home, they’ve then had another relapse. There’s only a very few number of cases that have been like that. So for all intents and purposes, I don’t think that’s something we should fear and it’s not something we’ve seen with the previous SARS outbreak in 2003.

Sunanda Creagh: And Tim would like to know: how will quarantine work in a family?

Lisa Sedger: Yeah, it’s interesting, isn’t it? We think of quarantine as being away from work or away from public places. But really, if you have been infected, then the people in your family are as at risk as your work colleagues would be at work. Again, I think it’s about just common sense. Don’t share food utensils, wash your hands, don’t keep touching your face and your mouth and your nose. Get rid of tissues in a nice sort of clean manner. It’s about minimising transmission.

Michael Wallach: Let me just add to that, that all the data indicates that children likely will only get very mild symptoms, if at all. So if you’re a family member and you’re worried about your children, this is one time that you can be happy about this. All the results so far indicate that children aged zero to nine, there’s not been a single death.

Lisa Sedger: Whereas what we do know is the elderly appear to be more susceptible to a more severe disease. So that’s where if I’m sick, it’s better not to go and visit my grandparents or something like that. That’s where quarantine within the family works in a practical sense.

Sunanda Creagh: And just to finish up, is there anything else that you’d like to add?

Lisa Sedger: Yeah, I think I’d just want to finish with a really positive note. I mean, we live in an amazing era of medical research and science. Within within a very, very short period of time, parts of the virus had been sequenced. We now track the virus in its entire sequence. We know, we have clinical trials for the drugs. We have people working on vaccines. We have epidemiologists better understanding the disease susceptibility within a population. I mean, we learn a lot from other existing outbreaks of infectious diseases. And I remain positive that, you know, the medical and scientific community working together will be able to solve this. I’m quite confident that there’s a really strong response. That’s not to diminish that people have died and it’s been tragic. But we live in an era where we’re exposed to infectious agents and we are getting better and better at controlling most of those infections.

Michael Wallach: So I’ll just add and put in a plug for a program I’m very much involved with called Spark working with people at Stanford. We established a program for exactly this time, when there’s sudden outbreaks. And the program now involves 23 countries and around 70 institutions, all working together for outbreaks of Zika, Ebola and now coronavirus. It gives me great hope that, apart from what you said, we’re now working together collaboratively like never before. We’re putting our egos outside and we’re saying we have social responsibility to do better. Certainly, in the case of a pandemic. And we’re doing it. And we’re very proud to be able to say we have 15 projects going on now collaboratively that we just formed over the past two weeks, together with our colleagues all over the world. I also believe in a very bright future.

Recording by postgraduate.futures at the University of Technology Sydney.

Audio editing by Sunanda Creagh.

Theme beats by Unkle Ho from Elefant Traks.

Are we alone in the Universe? The expert opinion on that, it turns out, is surprisingly consistent.

“Is there other life in the Universe? I would say: probably,” Daniel Zucker, Associate Professor of astronomy at Macquarie University, tells astrophysics student and The Conversation’s editorial intern Antonio Tarquinio on today’s podcast episode.

“I think that we will discover life outside of Earth in my lifetime. If not that, then in your lifetime,” says his fellow Macquarie University colleague, Professor Orsola De Marco.

And Lee Spitler, a Senior Lecturer and astronomy researcher at the same institution, was similarly optimistic: “I think there’s a high likelihood that we are not alone in the Universe.”

The big question, however, is what that life might look like.

We’re also hearing from Danny C Price, project scientist for the Breakthrough Listen project scanning the southern skies for unusual patterns, on what the search for alien intelligence looks like in real life - and what it’s yielded so far.

Everything you need to know about how to listen to a podcast is here.

Additional audio credits

Kindergarten by Unkle Ho, from Elefant Traks.

Lucky Stars by Podington Bear, from Free Music Archive

Illumination by Kai Engel, from Free Music Archive

Podcast episode recorded and edited by Antonio Tarquinio.

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