NARRATION

Here's a great mystery. In the good old days, there was plenty of poverty, hard times and sickness, but allergies were very rare. Tell these kids about your asthma or eczema, and they'd probably look blank. Cut to today. In the Western world, there's an epidemic of allergies.

Dr Alma Fulurija
People suffer various degrees of allergies, from stomach intolerances to full-blown anaphylaxis.

Professor Barry Marshall
In the 21st century, so many people are allergic to different foods - eggwhites, milk, I'm allergic to shellfish, peanuts is one that can be quite dangerous.

NARRATION
The question is, why? What was this generation doing right that we seem to be doing so wrong? Well, the answer might be tied up with a germ. Meet Helicobacter pylori - a very unusual tummy bug.

Professor Barry Marshall
This is a germ that lives in the stomach of more than half of all the humans on Earth.

Dr Graham Phillips
Now, it has its name - 'Helicobacter' - because of its helical shape. Indeed, the way it moves around your body is it spirals around by spinning these seven flagella.

NARRATION
But are these good bacteria, or bad? Definitely bad, Barry Marshall used to say. Indeed, he won the Nobel prize for proving it.

Professor Barry Marshall
We discovered that it caused ulcers. So it wasn't stress, it wasn't your genes or family - it was just a germ in your stomach. The great news being that everybody with ulcers can be cured in a week or two now with some antibiotics.

NARRATION
But now these bacteria might have a good side - preventing allergies. And amazingly, these days, Barry's trying to recast the germ as a medicine. To appreciate this turnaround, go back to 2005, when Barry and partner Robin Warren won their Nobel prize.

Professor Robin Warren
When they rang me from Stockholm, suddenly the blood from my head went down to my... I could feel it, you know.

NARRATION
Winning was sweet revenge, because right from the beginning, the establishment refused to believe bacteria were associated with ulcers.

News report
More rapid detection of H. pylori is possible by examining...

Professor Barry Marshall
We said, 'Well, hang on, let's get back a bit and just look down the ordinary old microscope and we can see these bugs everywhere.' And they said, 'Oh, no, you can't. It's just in Western Australia. There's something wrong with that place.'

NARRATION
In the old days, treatment for ulcers was to take medication indefinitely and reduce the stress in your life. So desperate to prove bugs were the real cause, in 1984, Barry swallowed some Helicobacter, hoping to deliberately give himself ulcers.

Professor Barry Marshall
I said to my wife, 'Oh! We were right!' She said, 'What?' I said, 'I took the bacteria, I've got the illness.' And she said, 'You did what?!'

NARRATION
But Barry did cure himself just with a dose of antibiotics. By 1990, the establishment was listening.

News report
The disease heals up and this is really an unbelievable step forward.

NARRATION
But what's Helicobacter got to do with the allergy-free old days? Well, you'll see when I'm tested for the bug using a chemical tracer.

Professor Barry Marshall
So the first part is that you are going to open that capsule up.

Dr Graham Phillips
So I see that's yellow. That's a lemon flavour, eh?

Professor Barry Marshall
Yeah. OK. So you're going to swallow that with a little drink of water.

Dr Graham Phillips
One of these, little drink of water.

Professor Barry Marshall
Yeah. And see if you can get it down all the way.

Dr Graham Phillips
Down it, then?

Professor Barry Marshall
Yeah, throw it down.

NARRATION
I could have Helicobacter but be completely symptom-free.

Professor Barry Marshall
OK.

Dr Graham Phillips
Didn't taste bad.

Professor Barry Marshall
Yeah. OK, just blow into that. Blow that balloon right up.

NARRATION
In fact, in 90% of people the bug is harmless. And that's one of the curious things about Helicobacter - normally, a disease-causing bacteria makes everyone sick. The other odd thing is Helicobacter's very common, especially in the developing world, where the majority of people carry it.

Dr Graham Phillips
A bacterium that's common and relatively harmless gets biologists suspicious. Maybe the body needs it in some way.

Dr Alma Fulurija
Helicobacter has been around for a very, very long time - tens of thousands of years - and in fact you can track the migration of humans out of Africa based on what Helicobacter strain they've got. So it's a bacterium that has evolved with humans and with man and it has mechanisms that has enabled it to survive within us.

Professor Barry Marshall
And so one of the questions people have been asking for a long time is, is there some useful purpose, some reason why the human race is so commonly infected with this bacteria? Maybe not now but perhaps in the Stone Age there was a reason why we were better off if we had it.

NARRATION
And my test results the next day give a hint to that reason.

Dr Alma Fulurija
Graham, hello.

Dr Graham Phillips
Hello.

Dr Alma Fulurija
So, have you got good news or bad news for me?

Dr Graham Phillips
I've got good news for you.

Dr Alma Fulurija
Oh, that's good. You've actually come up Helicobacter pylori negative. And as your test says here, no current infection detected. So you're good to go.

Dr Graham Phillips
Very good. So what percentage of the population in Australia would be like me, would be negative?

Dr Alma Fulurija
So, in Australia, most people are actually Helicobacter pylori negative, so about 80% of the population.

Dr Graham Phillips
Yeah.

NARRATION
And that's the clue to why Helicobacter might be helpful. Unlike the developing world, in the West, most of us are like me, and don't have the bug, but we do have allergies.

Professor Barry Marshall
Because the new information is that these bacteria and some other germs dampen down the immune system and perhaps give us about 50% protection from allergic phenomena.

NARRATION
It's called the hygiene hypothesis. Many believe we have allergies these days because our world is too hygienic and bug-free. That's unlike 70 years ago when Helicobacter was common here in Australia because family sizes were bigger, drinking-water less clean and kids played around more in the dirt.

Professor Barry Marshall
In the 20th century and now the 21st century, we're too clean. My grandchildren, they probably have to look around to find some dirt. Whereas of course it was everywhere when I was a kid. And so if you don't get exposed to these natural, really not very harmful bacteria, your immune system, if you like, gets a big surprise every time it sees something new, it starts becoming hyperactive.

Dr Graham Phillips
So, give all the kids these days a good dose of Helicobacter, allergy problems solved, you might think. Well, actually, that's kind of Barry's solution. But there are a couple of issues to deal with first. Number one - Helicobacter does cause stomach ulcers in 10% of people. And in 1% it causes stomach cancer. So to turn this germ into a medicine, it first has to be made completely safe.

NARRATION
The good news is Helicobacter usually only causes problems when there's been a long-term infection, not short-term use as a medicine.

Dr Alma Fulurija
Most people with problems, with ulcers, are over 50 years old, so that means that they've had Helicobacter for 30, 40 years of their life. So it's at this point that you start to see some problems associated with a chronic infection of Helicobacter. We take a neonate, a one-week-old mouse...

NARRATION
And Barry and the team have been sifting out the safer strands of the bacteria - ones that don't cause disease.

Professor Barry Marshall
We have thousands of strains of Helicobacter to choose from, so we're selecting them down, testing them on different animals - mice, gerbils, monkeys. And now recently, in the last couple of years, we've been giving them to the poor medical students - we do pay them, so it's not all that bad, bit of pocket money.

NARRATION
The first human trials to see if the drug works will begin in a couple of years' time.

Professor Barry Marshall
I can imagine that we could possibly help people with yearly hay fever.

Dr Alma Fulurija
It could be in a pill once a month or it could be a probiotic-like drink every day. It would more likely be something that you would have to deliver on a daily basis

NARRATION
Let's hope it's not too long before there's a whole new treatment for allergies.

STORY CONTACTS

Dr Alma Fulurija 
Immunologist
UWA

Professor Barry Marshall 
Microbiologist Nobel Laureate
UWA