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Cate Bryant: Willow.

Cate Bryant: She had these big eyes and this red hair and a big smile.

Cate Bryant: Willow, are you getting wet? Willow. Are you getting wet? You're soaking!

Cate Bryant: They told us that she'd consumed a parasite called Rat Lungworm. It's just exploded inside of her.

Richard Cairns: The worst thing was seeing Grace who was, you know, a gorgeous, gorgeous little girl just get so weak.

Sam Cairns: I remember saying to the doctor at one stage "What do you really think it is? What's your gut feel?" and I remember her saying, you know, "I'm pretty sure it's the worm". She said "The scan looks like the worm. She said "We just can't find it."

Katie Ballard: My rough-and-tumble Sam. You would never, in a million years, expect that eating that slug would have done what it's done. The only picture I can bring to mind is of that 'Alien' movie when you see, you know, a picture of, you know, things growing out of people's heads. Horrific, absolutely horrific.

John D'Arcy: The public health department didn't want you to talk about this?

Michael Bryant: They were of concern that it would create fear in the community.

Sam Cairns: They didn't want to create public panic.

Richard Cairns: The disease is out there.

John D'Arcy: One of the most frightening parasites on the planet is on the move. Rats infected with Rat Lungworms have spread from Queensland to New South Wales and are now moving further south. There are few diseases more terrifying than Rat Lungworm. The worm's larvae are passed on through rat droppings which are devoured by snails and slugs who can then spread the contamination to humans through their slime - say, on a lettuce leaf - or if they're eaten. Once ingested, the larvae find their way into spinal fluid and then, to the brain, where they hatch into needle-like worms and begin burrowing. In March this year, a baby girl called Willow Mae Bryant was playing in the backyard of this Sydney home.

Cate Bryant: She had these big eyes and this red hair. And a big smile.

John D'Arcy: Cate Bryant was 38 when Willow was born. She had two older sisters who loved her dearly.

Cate Bryant: Are you waving to Willow? Say "Hi, Willow!"

John D'Arcy: On Match 20 this year, 10-month-old Willow fell ill.

Cate Bryant: Well, in the weeks leading up to her getting sick it'd been really wet, so we'd had lots of slugs out on our deck.

John D'Arcy: And Willow loved to play on the deck.

Cate Bryant: It was just an ordinary day until I went to put her to bed

and she just wouldn't sleep all night. She had this little rattle in her chest and so the doctor had said "Take her down to emergency and get a chest X-ray." They couldn't pinpoint anything.

John D'Arcy: Willow's condition was rapidly deteriorating. She was transferred to Sydney Children's Hospital.

Cate Bryant: She'd just gone like a floppy doll.

John D'Arcy: Two weeks later after falling ill, Willow slipped into a coma. Doctors had no idea what was wrong with Willow. They'd never seen a case like hers before but they soon would. A few days after Willow

was admitted to hospital, another little girl on the same street, in the next suburb, fell seriously ill with exactly the same symptoms.



Sam Cairns: I decided to take her to the GP because she'd had a really restless night of waking up crying. Maybe she had a bit of bronchitis or chest sounded a bit rattly.

John D'Arcy: Grace, who looks a lot like Willow, is the daughter of Sam and Richard Cairns.

Richard Cairns: She was, you know, learning to crawl, almost learning to walk.

John D'Arcy: And, like Willow, 15-month-old Grace loved to crawl outside. Initially, doctors thought she had a mild throat infection but her mum Sam, a former paediatric nurse, suspected something more serious. Over the next week, she took Grace to seven different doctors but none of them could tell her what was wrong. All Sam knew was that her baby was getting worse. You ended up taking Grace to the hospital?

What happened?

Sam Cairns: By that stage, I thought there was something wrong with her head. I could feel that her fontanel - so, the soft spot on her head -

was raised. It wasn't flat anymore and it was kind of a bit hard.



John D'Arcy: Most incidents of Rat Lungworm disease pass harmlessly but in the worst cases, the worms eat into the brain which is why early detection is so important. But Grace's doctors were baffled.

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