S1: From the newsrooms of the Sydney Morning Herald and The Age.
S1: This is the morning edition. I'm Tammy Mills, filling in
S1: for Samantha Selinger. Morris. It's Wednesday, May 28th. A few
S1: years ago, Australia earned the unenviable title of Allergy Capital
S1: of the world. This could well have been true with
S1: a World Allergy Organization review finding Australia had the highest
S1: rate of food allergies for children under five. But since then,
S1: something happened to turn allergy advice on its head, and
S1: parents have been introducing allergens to children at a far
S1: younger age than they used to. So where are we
S1: at now? Explainer reporter Jackson Graham is here with us
S1: today to discuss whether the new strategy has worked. Welcome, Jackson.
S2: Thanks, Tammy. Really great to be here.
S1: Jackson. First up, can you explain what allergies are and
S1: how you know if you actually have one?
S2: So if you talk to teachers, chefs and allergy specialists today,
S2: they'll basically tell you that there's been a big rise
S2: in allergies and intolerances in their jobs. Um, there's around
S2: 5 million people living with allergies in Australia, and up
S2: to a third of the population is expected to experience
S2: an allergy sometime in their lifetime. I'm one of those.
S2: I have a tree nut allergy. I found this out
S2: when I was four years old. I was at home
S2: and I was annoying my grandmother, who was living with
S2: us and recovering from a hip replacement. Uh, my mum
S2: was making a nut loaf in the kitchen, and so
S2: to distract me, she gave me a Brazil nut to
S2: try to crack open with my hands. Um, and then
S2: almost immediately, my fingers started swelling. Uh, there was this
S2: really great pressure. Uh, so it was so bad, it
S2: caused me to actually bite my fingernails, which meant that
S2: I ingested a tiny fragment of the nut. Oh, right.
S2: And from there, I started to have anaphylaxis. So coughing, wheezing,
S2: hives breaking out all over my body. Uh, fortunately, my
S2: parents got me to a doctor pretty quickly. Uh, and
S2: ever since, I've basically had to avoid anything with nuts,
S2: so I've never had an almond croissant, a Waldorf salad,
S2: a duck, a chicken, or even something like Nutella. But
S2: after all these years, I only really delved into what
S2: makes this any different from an intolerance recently. In fact,
S2: I actually used to work at a as a waiter,
S2: and I remember the endless allergies that used to come
S2: in and intolerances. Um, and I'd have to understand, ensure
S2: people didn't eat the wrong thing.
S1: So what's the difference between an allergy and an intolerance?
S2: So remarkably, around 65% of the world's population has some
S2: degree of intolerance to lactose. For example, there's a bit
S2: of a crossover between allergies and intolerances. Intolerances cause allergy
S2: like symptoms, bloating and cramps after drinking milk or a
S2: rash from soap that irritates your skin. Uh, but in general,
S2: the key difference between an allergy and intolerance is the
S2: allergy affects the immune system. It's basically because the immune
S2: system has learned that certain proteins in things like eggs,
S2: cows milk, peanuts, tree nuts, shellfish, bee venom, pollen, or
S2: even animal dander Is a threat to the immune system.
S2: It's learned that. So antibodies called IgG become attached to
S2: a person's immune cells. Uh, and basically those cells detonate almost.
S2: It's a when when the body comes into contact with
S2: the protein again. Um, so it sets off this sort
S2: of chain reaction. Um, so then, yeah, the next time
S2: the body encounters these things, it sends the immune system
S2: into meltdown. Some people will become congested. They have itchy eyes,
S2: they sneeze, they vomit, or it can be life threatening.
S2: Setting off this kind of this reaction, which is known
S2: as anaphylaxis, where someone's throat closes over or their cardiovascular
S2: system shuts down. Uh, that's of course, unless they're administered
S2: quickly with adrenaline. The difference is that the allergies have
S2: this potential to make people extremely sick through through anaphylaxis.
S1: Okay. And so where does Australia sit in comparison to
S1: the rest of the world in terms of allergy rates,
S1: like has that actually been going up and are allergies
S1: more common now.
S2: That's a great question, Tammy. So if you ask any pediatricians,
S2: there's definitely a consensus that allergy rates have gone up
S2: in recent decades. Um, but unfortunately, cases weren't really measured
S2: that well before the 1990s. Um, so there certainly are
S2: stories out there of people who suffered allergies well before then. Um, actually,
S2: in fact, my mom was one of those she, you know,
S2: would get hives from certain pollen as a child and maybe,
S2: you know, there's some genetic basis for it. Um, which
S2: is interesting. But yeah, we've had great studies in Australia.
S2: In 2011, the Murdoch Children's Research Institute found that food
S2: allergies affect about 10% of all children in Melbourne. Um,
S2: and this particular study gave rise to the catchphrase, uh,
S2: that you mentioned in the introduction that Australia is the
S2: allergy capital of the world for this young age group.
S2: That could well be true. You know, two years later,
S2: the World Allergy Organization found that there was the highest
S2: rates of food allergy, were, in fact, uh, in children
S2: under five in Australia, followed by Finland and Canada. Yeah.
S2: But for food allergies among anyone under the age of 18.
S2: Britain actually topped that list and Australia ranked 11th. Um,
S2: so I think the the data globally is is a
S2: bit patchy. Um, but there certainly is a picture emerging
S2: that that allergies are affecting a large part of the population. Uh,
S2: and hay fever is another example. It affects something like
S2: 1 in 5 people in Australia. So look, you know,
S2: there's a consensus among among allergists that that basically they
S2: are seeing more and more of these cases. And I
S2: think although the data is difficult to prove, uh, it
S2: seems to be the case.
S1: That's kind of surprising, because I guess the image or
S1: perception of Australia is that we're like outdoorsy people that
S1: are hardy and wouldn't have such things such as allergies.
S1: But what's happening in Australia, like, why do we seem
S1: to have more children with allergies?
S2: Yeah, that's that's a great point, Tammy. And uh, indeed,
S2: we're sort of seen as, you know, not being too,
S2: you know, overly cautious about, um, you know, exposing ourselves to,
S2: to allergens and germs and things like that. So probably
S2: the biggest difficulty with allergies is that we don't know
S2: exactly what causes them. Um, this this actually has a
S2: big effect on on the whole thinking around allergies. They're
S2: a bit of a challenge to know. There's certainly a
S2: challenge to know how to prevent. So there are several
S2: theories about what causes them. And you sort of touch
S2: on one there. The biggest is that, um, there's something
S2: called the hygiene hypothesis. Um, it's important to really note here, though, that,
S2: that these are just theories, like there's probably not one, uh,
S2: cause for allergies. Okay. And, well, to put it in
S2: the language of scientists, it's what they call multifactorial. So
S2: there's probably a range of things going on that are
S2: causing allergies. Okay. Um, the hygiene hypothesis basically says that
S2: that as a society, as society has industrialized more, it's
S2: become cleaner and meaning that we're less exposed to germs
S2: and dirt than in the past. There are even studies
S2: showing a relationship between living on a farm or having
S2: a dog at home. That suggests that these children are
S2: less prone to allergies. Um, there's other theories that are
S2: linked to this idea that actually zoom right into our
S2: gut and, and suggest that within something called the microbiome,
S2: we don't have the right mix of viruses and bacteria
S2: that are supporting the immune system, and that might be
S2: making us more susceptible to allergies. Other theories suggest that
S2: we don't get enough vitamin D exposure. Um, maybe the
S2: weather or our genes play a role too. Um, so
S2: as you can see, there's there's there's all of these factors.
S2: What I found really fascinating when I was working on
S2: this piece is that one researcher named Professor Sheryl van
S2: Nunen in Sydney's Northern Beaches found a tick bite was,
S2: in fact causing, uh, cases of meat anaphylaxis among, uh,
S2: sort of older, older age groups and not children. They
S2: had all never previously had an issue when eating meat.
S2: And basically the tick, uh, picked up a sugar molecule
S2: called Alpha Gal, uh, which they passed on to humans
S2: when they, when they, uh, bit the human, too. So
S2: meat anaphylaxis cases, uh, seem to have increased when fox
S2: baiting was introduced and the animals, the ticks fed off proliferated.
S2: So this is a bit of a niche allergy. It's
S2: a it's anaphylaxis from uh, to meat later in life.
S2: But what's interesting is that it perhaps sums up the
S2: challenge with with pinpointing the causes of allergies. As you
S2: can see with this case, there's this complicated interaction between
S2: the environment and our biology at play.
S1: It's surprising. Right? Because you would have thought, well, at
S1: least like I would like to think that with all
S1: that we know and how far ahead we are with science,
S1: that we would be able to find a cause for allergies.
S1: So that's super interesting. What about the age that children
S1: are exposed to allergens? Does that have anything to do
S1: with it?
S2: So around the time I was diagnosed, parents were told
S2: not to introduce children to common allergens before three years
S2: of age. And now ask any new parent and they're
S2: told basically to introduce things like nut butters, cooked egg,
S2: cow's milk to their babies from between four months and
S2: and at least before 12 months of age. What Allergists
S2: have found out in recent years is many children avoid
S2: getting food allergies if they're introduced to the food early enough.
S1: Okay.
S2: The thought here is that it seems to prime the
S2: immune system being introduced to the food.
S1: Okay.
S2: So the old advice wasn't helping, and maybe even it
S2: was contributing to people getting food allergies. It's a remarkable
S2: change to have the advice shift so dramatically, and has
S2: been a task for health professionals to teach the public about.
S1: We'll be back in a minute. This is bringing up
S1: very vivid memories for me as a new parent myself,
S1: and having gone through the list of allergens and testing
S1: your child, you know, at around six months or before
S1: they're 12 months of age. So I can definitely relate.
S1: One of the really things I found fascinating about your
S1: piece is that you spoke to the professor who was
S1: actually responsible for turning this advice. So when to introduce
S1: children to allergies on its head? Ted. So can you
S1: tell us a bit about what led him to this discovery?
S2: Yes. So his name is Gideon Lack, an allergist in London. Uh,
S2: changing advice like this, it must be the most amazing
S2: moment in any researcher's career. Um, it's. And it's fascinating
S2: to learn the backstory. Um, of course, he was soaking
S2: in the world of allergies for years. Uh, which is
S2: worth noting, uh, which obviously helped him know what the
S2: right questions were to ask. Um, but what really spurred
S2: him along was asking pediatricians at a conference in Tel
S2: Aviv in the early 2000 how many children they saw
S2: with peanut allergy. Their answer was hardly any, uh, whereas
S2: in London it would have been nearly every doctor. What
S2: he found was many parents in Israel gave their children
S2: a snack called Bamba, basically a corn puff dusted in
S2: peanut butter. He went and tested the rates between Israel
S2: and the UK, and then set up groups of British
S2: children exposed to or not exposed to peanuts from an
S2: early age, and found that exposing the children to peanuts
S2: showed a 90% reduction in peanut allergy.
S1: Huge. And did this flow on to what happened in Australia.
S2: So in 2016 we changed the guidelines to introduce allergens
S2: to children between four months and 12 months of age.
S2: And the result of that is that it appears to
S2: have slowed the rate of peanut allergies, uh, in Australia.
S2: It hasn't stopped them or reversed them, but it has
S2: certainly slowed their increase. The rates of hospital presentations have
S2: dropped for nearly every age group are following that advice.
S2: But they, interestingly, slightly rose for babies younger than one.
S2: The group who the advice applies to the most.
S1: Okay.
S2: Yet even then, when she zooms in on this age group,
S2: this group of babies who are having the allergens earlier
S2: than they otherwise would have. The rise in presentations don't
S2: actually equate to more admissions into those hospitals, and crucially,
S2: it doesn't actually result in more cases of anaphylaxis.
S1: Okay. So it's possible that there's a reaction of some kind.
S1: And because parents are giving babies these allergens earlier, so
S1: then they're rushing to the hospital to make sure it's
S1: not anaphylactic reaction.
S2: It's possible. You know, there could be, uh, you know,
S2: a skin rash as a result of, uh, the food,
S2: you know, being applied around the mouth rather than in
S2: the mouth or little triggers that, you know, make parents
S2: think perhaps, you know, this is, uh, a reaction, uh, but,
S2: you know, it's not actually leading to more admissions.
S1: Oh, interesting. Another thing that I found fascinating in your
S1: piece is this possible link between asthma and allergies. What's
S1: this about?
S2: Okay, this is fascinating. So, Gideon Lack in London has
S2: found children with dry or broken skin. So basically, eczema
S2: of varying severity are more likely to develop an allergy.
S2: I should flag here that the evidence for this is
S2: still circumstantial rather than proven through a rigorous study. But
S2: the thinking is that perhaps proteins from, say, peanut butter
S2: get passed into the baby's skin when people touch them
S2: or they're around the food.
S1: Okay.
S2: Maybe this leads to the immune system learning those proteins
S2: are a threat rather than getting to know them through
S2: the digestion process. It's an interesting theory and could be
S2: one explanation for how food allergies come about. So of course,
S2: the early introduction of food through small portions put into
S2: babies mouths, as health authorities now advise, could be one
S2: way of blocking off eczema as a possible cause or
S2: pathway for allergies.
S1: Okay, so you're kind of saying there that it's if
S1: a baby or a child has eczema and if a parent, say,
S1: touches them with peanut butter or some such on their hands,
S1: even without meaning to or like just within the throes
S1: of daily life, which you would that possibly that could
S1: be causing an allergic reaction. Yeah, potentially.
S2: Basically it's the body would be encountering that allergen for
S2: the first time through the skin rather than through the mouth.
S1: That's so interesting. But the long or the short of
S1: it is, there seems to be no solid answer for
S1: what causes allergies, which is highly annoying, but I guess
S1: that's humans for you. But what about cures for allergies?
S1: Is there a cure for one?
S2: So there have been treatments such as antihistamine, which we've
S2: many of us will have heard of. Uh, and that's
S2: been around since at least the middle of last century.
S2: And that for allergies such as hay fever and of course,
S2: there's adrenaline for anaphylaxis. Um, but for food allergy, there
S2: have been few actual cures in Australia at least. Uh,
S2: so the one that has shown the most promise is
S2: offered in the United States. And it's a form of immunotherapy,
S2: oral immunotherapy, where someone is given small doses of the
S2: food under controlled conditions over potentially months until they build
S2: up their tolerance to it. Yeah, not everyone responds to it,
S2: but it does seem to desensitize many people. Allergies can
S2: be very sensitive to the ups and downs of the
S2: immune system on any given day, so something like a
S2: cold or even exercise can actually influence how severe someone's
S2: reaction is. So that's one reason the dosages have to
S2: be tightly controlled rather than simply administered at home. Um,
S2: there have been families in Australia who have actually travelled
S2: to the US to get this treatment. Uh, but fortunately
S2: it is becoming increasingly available here, too. Uh, there's a
S2: program in ten hospitals across Australia at the moment for
S2: babies with peanut allergy. Um, it will be interesting to
S2: see if this gets expanded to more allergens and older
S2: ages and further hospitals. Um, I guess in the meantime,
S2: living with analogy makes people like me at least a
S2: little more cautious. Um, at the worst, it's it's living
S2: with a lot of worry, uh, such as navigating a
S2: trip overseas or a dinner party invitation that can feel
S2: like walking on eggshells.
S1: Given the allergy that you have. What was the most
S1: surprising thing about this piece that you've written? What did
S1: you discover that was new and interesting to you?
S2: Probably that, you know, early introduction advice, um, was really
S2: surprising to me because, yeah, obviously when I was a
S2: baby that was never around, I would have never eaten
S2: a nut before that day where I was handed, you know,
S2: a Brazil nut and basically had it in my hands.
S2: And I was four then. So the idea that, um,
S2: babies should be sort of given these to kind of
S2: prime their immune systems, you know, long before they even
S2: reach one year of age, is a big change in advice.
S1: And in such a short space of time. Really?
S2: Yeah, exactly. And I suppose the other thing that surprised
S2: me was just how alert you have to be to
S2: all of the different, you know, kind of possibilities of
S2: what could cause allergies. And it's probably as, as we
S2: talked about doesn't have one cause. So, um, it's hard
S2: for us to think about that. You know what? There
S2: could be, like, multiple things working together that are that
S2: are kind of causing us to become more prone to allergies.
S1: Well, thank you so much, Jackson, for your time. It's
S1: been a really interesting conversation.
S2: Thanks, Tammy. Thanks so much for having me on.
S1: And for anyone wanting more information, please do check out
S1: Jackson's explainer on our website so you can find a
S1: link for it in our show notes. Jackson. Thanks again.
S2: Thanks, Tammy.
S1: Today's episode of The Morning Edition was produced by Josh towers.
S1: Tom McKendrick is our head of audio. To listen to
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S1: I'm Tammy Mills, this is the morning edition. Thanks for listening.