Weekend Australian - Ticks Story - Ministry of Health

MOTORING | BRIAN COX | TRAVEL | DAN WYLLIE | FASHION | HELEN YOUNG | FOOD

JULY 16 - 17, 2016

ONCE BIT TEN

By Anne Barrowclough

A LUSH SUBURB. A MYSTERIOUS CLUSTER OF ILLNESSES.

WHO COULD CRACK THE CASE?

Page 1 of 6

16 Jul 2016Weekend Australian, Australia

Author: Anne Barrowclough • Section: Magazine • Article type : News ItemClassification : National • Audience : 227,465 • Page: 1 • Printed Size: 5802.00cm²Market: National • Country: Australia • ASR: AUD 189,477 • Words: 3956Item ID: 625626015

Licensed by Copyright Agency. You may only copy or communicate this work with a licence.

THE UNUSUAL SUSPECT

It began with a puzzling cluster

of patients with severe allergic

reactions to red meat. What was causing it? The

answer surprised even doctors

By Anne Barrowclough

Photography Nick Cubbin

S

Page 2 of 6




Careful: Nicholas and Joy Cowdery

anelle Williams was flying to New York from her Sydney home, looking forward to a holiday. It was 2012, and she had taken every precaution to ensure an incident-free flight. She’d ordered a vegan meal, refused wine with dinner, and in her bag were specially sourced toothpaste and

cosmetics, their ingredients scrutinised for hidden dangers. Everything was in order.

A couple of hours after the dinner service, as Williams settled in to watch an in-flight movie and sleep, she started feeling queasy. “I thought I should stand up,” she says, “but when I tried to walk around I started gasping. I couldn’t breathe. It was very, very frightening. It’s a terrible feeling… a feeling that you are going to die.”

In the dark of the aircraft cabin, Williams was going into anaphylactic shock – the most severe, life-threatening allergic reaction possible. If the cabin crew hadn’t reacted quickly, immediately giving her an adrenalin injection and keeping her airways open, she could have died on that flight. Upon landing, she was rushed to hospital.

Later, Williams contacted the airline and asked for a list of the ingredients in the lentil stew she’d had for dinner. She spotted the culprit immedi-ately. Butter. A couple of spoonfuls of it in her meal had nearly killed her. “Now I can’t even trust the vegan options,” she says. “I take my own food when I fly. It’s the only way to stay safe.”

Williams has a little-understood allergy. She’s allergic to all mammalian meat – beef, pork, lamb, kangaroo, for example – and also allergic to meat products, including dairy and anything contain-ing gelatine. She cannot drink white wine – some winemakers use milk in the fining process – or use regular toothpaste, which contains glycerin. Even some moisturisers include traces of animal by-products. The list goes on: tablets coated with gelatine are out, and now she is trying to find an HRT medication that doesn’t include magnesium stearate, which contains a bovine derivative.

Her allergy is so strong that if her husband Stefan kisses her after he’s eaten red meat, her lips swell up. Last New Year’s Eve at a friend’s house, smoke wafting over from a neighbour’s barbecue gave her a severe reaction. “There is nothing I can put into or on my body without researching the

ingredients,” says Williams, who lives on Sydney’s northern beaches. “It takes over your life.”

Not far away, on Sydney’s Pittwater, Joy Cowdery went into anaphylactic shock one night in 2005 after eating a small piece of beef, later learning that she had somehow developed a severe allergy to red meat and dairy products. Now, even if she eats a piece of chicken that has been cooked in red meat stock or wrapped in prosciutto, she could die.

A few kilometres away in Sydney’s northern suburbs, Suzie Maher has experienced the horror of watching her son Liam, four, go into anaphy-lactic shock three times after eating meat. Liam can’t have milk or cream, he can’t eat birthday cake at day care in case it contains dairy products; he can’t have lollies, in case they contain gelatine. Liam can’t even be vaccinated as the medications contain bovine byproducts.

Janelle, Joy and Liam are among a growing group of Australians who have developed aller-gies to mammalian meat and, in many cases, its byproducts. Their lives and those of their families are hugely restricted: some can’t even cook red meat for other people without risk of a severe reaction. Some, like Janelle, who’s at the extreme end of the allergy scale, have adopted a vegan lifestyle in order – literally – to survive.

In the early 2000s, Sydney immunologist Sheryl van Nunen started seeing a cluster of patients with mysterious allergic symptoms. Some had woken in the middle of the night vomiting, some had gone into anaphylactic shock in the early hours of the morning. Others had found themselves covered in hives, their faces swollen.

In her long career as a leading expert in aller-gies, Van Nunen hadn’t seen anything quite like it. There seemed to be no reason for the allergies and the timing of the reactions didn’t fit any clas-sic pattern. Most people who are allergic to, say, eggs or prawns, react within an hour or two of eating them. But these patients were experiencing a reaction eight to 10 hours after eating.

“Some of them were waking up at 2am with fast-acting anaphylaxis – what I call ‘Drop down and drag them out’ because they go to the bath-room and drop down and you have to drag them out to the ambulance,” she says. “It was instant and severe. I had to find out what was causing this.”

J

Page 3 of 6




18 THE WEEKEND AUSTRALIAN MAGAZINE

Van Nunen was head of the Department of Allergy at Royal North Shore Hospital for 27 years, during which time she was the chief investigator in clinical trials of 75 per cent of all new treatments for allergic conditions intro-duced to Australia. She now runs an allergies clinic in Chatswood in Sydney’s north, and it was here that she first encountered this strange cluster of cases.

“Apart from latex or semen allergy there’s nothing that happens in the middle of the night,” she says. “You question people very care-fully and that didn’t come up. I thought, all I can do is ask them to bring everything they ate at the last meal, and we did pin prick tests.” Unlike many allergy experts, she does pin prick tests using food, rather than allergens in bottles. “When I pricked raw meat,” she says “we’d get quite a decent reaction on the skin – a 6x6mm weal. My colleagues at Royal North Shore were seeing the same thing; these people were aller-gic to mammalian meat.”

Van Nunen had seen isolated cases of red meat allergy since the 1980s, but it was considered extremely rare. And nothing in the new patients’ histories revealed reactions to the more common allergens such as bee stings or nuts.

But they did have one thing in common. When asked to tick off a list on a medical his-

tory form that included eczema, asthma, hives and reactions to insect stings, “people would fill in the form then add an annotation”, recalls Van Nunen. “They’d say, ‘I haven’t had any bee stings, but I have had a tick bite’.

“After a number of people said this, it seemed to me that every time there was a middle-of-the-night anaphylaxis it would turn out to be from eating mammalian meat after tick bite, even though the tick bite might have been months earlier. Not only that, but they seemed to have had a large local reaction at the site of the tick bite. We also had this problem of the time lapse between them eating the meat and having a reac-tion hours later. So I thought, ‘There must be something to this’.”

By the time Joy Cowdery appeared in her clinic in 2005, Van Nunen had seen 22 people from Sydney’s coastal areas with similar symp-toms. Joy was patient number 23.

Joy and her husband, former NSW director of public prosecutions Nicholas Cowdery, spend every other weekend at their holiday house on Pittwater, an idyllic spot in Sydney’s north. Sitting right on the water, accessible only by boat, their

house is set in natural bushland, where brush tur-keys and bandicoots are frequent visitors. That was another piece of the puzzle right there.

“The areas around Pittwater are ideal for ticks,” says entomologist Stephen Doggett, from NSW Health Pathology. “You’ve got water on both sides of the peninsula, it’s humid, there’s a lot of bush. It’s a tick hotspot.”

Any pet owner who lives in such an area will know of the precautions needed to protect their animals from the paralysis tick Ixodes holocy-clus, the most common of the 75 tick species found in Australia. Typically, ticks lie in wait among foliage until a potential host passes close by; after climbing aboard, they puncture the host’s skin with their mouthparts and begin sucking blood, feeding like this for several days before dropping off, engorged and sated.

While one tick bite can be fatal for a cat or dog, until this century it had never been regarded a potential danger to humans, the controversy over Lyme disease notwithstanding.

(Lyme disease, linked to tick bites and identifi-able by a bulls-eye rash, is a debilitating illness that causes extreme muscle pain and fatigue. While some Australian doctors claim to have diagnosed it in patients who haven’t travelled to countries where it is endemic, the government and the Australian Medical Association do not recognise it here. A Senate inquiry into “growing evidence of an emerging tick-borne disease that causes a Lyme-like illness” was halted in May when the House was dissolved for the election.)

Joy Cowdery, for one, would never have believed that the garden of her weekender might harbour a tiny insect that could kill her. And like many Australians, she was sanguine about tick bites. “Every time we would get off the boat to the house we’d be bitten,” she says. “We must have been bitten hundreds of times, but we never really thought anything of it.”

One afternoon in 2005, while making a beef casserole, Joy tasted a piece of the cooked meat. An hour later, she started to feel very ill. “I was itching, it was hard to breathe, I had hives all over me. I was cold, then hot. I knew I was in anaphy-lactic shock.” Her husband rushed her to the local Mona Vale Hospital for treatment.

A week later, after she’d recovered, she was referred to Van Nunen, who asked her to bring in all the types of food she had last eaten before she’d gone into anaphylaxis. After testing her for 10 different ingredients, the professor found that Joy was allergic to mammalian meat.

Joy and her husband found it difficult to

believe. “Nick said, ‘Let’s do an experiment. Let’s have some roast lamb.’ So we did, and at about one in the morning I woke up itchy all over. Nick had to admit she was right.”

It’s been life changing, says Joy, who works part-time as a school teacher. “I have to use dif-ferent plates and utensils at home so there’s no cross-contamination with Nick’s meals; I can’t work on a barbecue because the vapours would get to me, and I can’t be near the sausage sizzle at school. I can’t drink white wine or eat choco-late because of the milk content.

“But however careful you are when you’re eating out, you never really know. I’ve found that even if I’ve just had vegetables I suddenly have to rush to the loo because there’s been cross-contamination. Perhaps the same spoon was used to stir the vegetables as was used on a meat dish. Or the chicken was poached in veal stock. You just don’t know.”

Clues: Sheryl van Nunen; Liam Maher;

an engorged tick

Page 4 of 6




19THE WEEKEND AUSTRALIAN MAGAZINE

In 2007, Van Nunen became the first immunologist in the world to describe in a pub-lished paper the link between ticks and meat allergy. But a riddle remained: why were so many of her patients, like Joy, developing their allergies months after they’d been bitten? Such a time lag had never been seen before with food allergies.

“I wondered if a tick bite was switching people to being pro-allergy,” she says. “After all, why couldn’t a parasite alter your immune system, why couldn’t it transfer an allergen that causes a late reaction? It happens in asthma – people can have either an immediate reaction to a dust mite, or it can come four to six hours later, or both.

“So I thought, late reactions occur in other things; this might be one of those. We haven’t seen them with food before but with allergy there’s always something you haven’t seen before. It’s a weekly phenomenon.”

Meanwhile, US scientists were examining

why nearly one in four cancer patients in Tennessee and North Carolina treated with the drug cetuximab developed a severe allergic reac-tion, compared with less than one in 100 else-where. After lengthy analysis, they discovered the culprit: a substance known as alpha-gal, which came from antibodies in the drug derived from mice. A paper subsequently presented to the American Academy of Allergy Asthma & Immunology reported 10 patients with recurrent anaphylaxis triggered by eating beef or pork, all of whom were alpha-gal allergic after being bitten by ticks.

The pieces of the puzzle were coming together.Alpha-gal – or, to give it its full scientific

name, galactose-alpha-1,3-galactose – is a car-bohydrate found in the blood of all mammals except for humans and the great apes. When ticks bite a mammal such as a bandicoot, possum or rat, they pick up the alpha-gal, and when they go on to bite humans, it is trans-ferred. On the face of it, this shouldn’t matter: it’s usually proteins that cause serious allergies. But once the tick has picked up alpha-gal, it binds to a tick protein – and when the tick bites a human, the combination of protein and alpha-gal is injected into the bloodstream. While the human immune system “should” ignore the alpha-gal and attack only the protein, because they’ve arrived together the immune system regards them both as equally dangerous. After some time – weeks or sometimes months – the immune system has altered; it has become trained to react to alpha-gal.

Alpha-gal is found in all mammalian meats. So when someone whose immune system has been altered in this way eats the meat, they suffer an allergic reaction; sometimes mild, no more than an upset tummy, sometimes much more severe.

Liam Maher had his first reaction a month after he was bitten by a tick last year, when he was just three. He woke up at 10pm crying and his parents noticed a rash over his torso and neck. They rushed him to Hornsby hospital. It was only minutes away but by the time they arrived, the rash had turned into welts. Within two minutes of arriving Liam was desperately gasping for breath. And he kept going into anaphylaxis even during treatment: his little body was still digesting the meat he’d eaten at dinner, so it was releasing more allergen into his system.

His mother Suzie reported that a week earlier Liam had been bitten by a number of ticks, but the doctors at Hornsby didn’t make the connec-tion. It took two more anaphylactic reactions over

the following fortnight before a connection was made. “The third time we went back with the same thing, a doctor put it together very care-fully,” Suzie says. “He told us not to feed Liam meat. But because he said red meat, in my infinite wisdom I fed him pork. He had another reaction and I was finally advised that it was all mamma-lian meat.” Subsequent tests confirmed the diag-nosis, showing his allergy levels were very high.

“We’re now hyper vigilant,” says Suzie. “We’re always worried when we take him out to eat. I have to research everything. I’ve had to tell his school that he can’t have birthday cake when it’s another child’s birthday, he can’t eat lollies or jelly; it’s too dangerous. I have to make him his own cake when there’s a special occasion.

“But the big challenge is immunisation, because the ingredients of the vaccines are bovine derivative. The immunisation clinic at the Children’s Hospital at Westmead is trying to find one that doesn’t contain bovine by-products, but until then I can’t get him vaccinated.”

Since Van Nunen’s breakthrough paper in 2007, scientists have discovered thousands of cases of what is now known as alpha-gal allergy or Mammalian Meat Allergy (MMA) in the US and Europe. But Australia has the highest preva-lence in the world – at least 10 times that of any other country. Cases of MMA have been con-firmed along our eastern seaboard, with Sydney and Noosa particular hotspots, and a handful of cases in Victoria.

In a 2014 paper, Van Nunen reported that in the northern beaches area where most of her patients live, she had diagnosed more than 500 people with MMA. That’s one in 880 of the local population. In the two years since that report, the number of diagnoses has doubled. In the next most prevalent region – the US state of Virginia, with a population of eight million, scientists have reported 1000 people with MMA. The numbers reported in the rest of the world are scant by comparison: four in Central America, 22 in France, 44 in Sweden, one in Japan.

In 2013, a study published in the journal Emergency Medicine Australasia reported more than 500 cases of tick reactions over two years at the emergency department of Mona Vale Hospi-tal on Sydney’s northern beaches. The study found that about six per cent of those people had anaphylaxis. In just one street in nearby Oxford Falls, a bushland suburb whose residents I inter-viewed, four people have been confirmed with MMA in the past six years.

I HAD TO FIND OUT

WHAT WAS CAUSING

THIS

Page 5 of 6




20 THE WEEKEND AUSTRALIAN MAGAZINE

PHOT

OGRA

PHY:

DAV

ID S

WIF

T; S

TEPH

EN D

OGGE

TT /

WES

TMEA

D HO

SPITA

L

But MMA is not the only damage these tiny creatures can inflict on humans. Van Nunen now sees at least two people a week with either tick-induced MMA or tick anaphylaxis, but the two are very different. MMA is caused by the alpha-gal carbohydrate in meat, while tick anaphylaxis is caused by the tick itself – specifically, an allergy to a protein in its saliva. While deaths are rare – there have been no recorded deaths from MMA and just three in the world from tick anaphylaxis – both are regarded as potentially life threatening. “MMA is more common,” says Van Nunen, “but 75 per cent of people with tick anaphylaxis have a grade 3 or grade 4 reaction. Grade 3 is, ‘We can do great things for you with adrenaline and oxygen.’ Grade 4 is, ‘We hope your will’s up to date and we’ll have a crack at it.’ These are very serious.”

In Australia, tick anaphylaxis is much more prevalent than bee anaphylaxis. “Since Septem-ber 2011, I’ve seen 152 people with tick anaphy-laxis and in the same time four people with wasp and four people with bee venom anaphylaxis,” says Van Nunen. “That’s nearly 20 times as many with tick anaphylaxis. It’s quite remarkable.”

Ixodes holocyclus, the tick that causes MMA and can also kill dogs and cats, is found down the east coast of Australia, from Queensland to north-ern Victoria, and up to 100km inland. You’ll find ticks in these humid regions wherever you find leafy plants, although the idea that they will drop from trees onto your head is wrong – they seldom venture more than about 6cm from the ground. But if you have ferns or leafy shrubs in your garden, you will almost certainly have ticks.

And their numbers appear to be increasing. “We’re seeing a lot more ticks than 10 years ago,” says entomologist Stephen Doggett. “Council workers on the northern beaches are reporting that they’re seeing a huge increase.”

There is no hard scientific evidence for why tick numbers are increasing, but scientists such as Doggett and Peter Banks, Professor in Conserva-tion Biology at the University of Sydney, put it down to the introduction in 2000 of fox baiting in Sydney, which has led to a large increase in numbers of tick hosts such as bandicoots, black rats and brush turkeys, which foxes routinely prey on. Van Nunen’s 2014 paper also pointed to an increase in host numbers: she named bandicoots and, in the US, white-tailed deer.

Where I live, in Avalon on Sydney’s northern beaches – tick central, according to Doggett – neighbours say they never had ticks in their gar-dens until fox baiting started. One neighbour who

has been in Avalon for 30 years says it was only when bandicoots started digging up the garden that his family started being bitten by ticks.

Banks argues that bandicoots are being blamed unfairly for the problem and recently published a paper arguing that even if bandicoots were eradi-cated, the ticks would simply transfer to another host. “It’s become its own dogma,” he says. “The number of bandicoots compared with the num-ber of other potential hosts including black rats, possums and brush turkeys isn’t that big.”

Doggett disagrees. “I would say bandicoots are a serious host. The ticks on possums are a different type of tick, and I’ve never seen ticks on brush turkeys. Holocyclus ticks aren’t so good on birds. If we could prove the bandicoot link, we could bait. But we haven’t done those studies yet. We need other studies, as well. We wonder if there’s a link we haven’t explored between the [tick saliva] and the frequency of the bite that leads to MMA and anaphylaxis,” he says. “We wonder why there has been such an increase in cases in Australia. Why are there so many cases of MMA here compared with the rest of the world?”

There are many questions as yet unanswered. Scientists don’t know, for instance, how some

people can be bitten by ticks for years with no problems. And how in people such as Joy Cowdery, bite reactions became more severe over time. “The more I got bitten, the larger the swell-ing,” she says. “One weal was 11x14cm big.”

Dogggett and Banks, both of whom have also been bitten hundreds of times by ticks, say the risk of becoming alpha-gal allergic may well depend on what stage of growth the tick is at – larva, nymph or adult – and what host it has previously fed on, when it latches onto a human.

Alpha-gal allergy is not just a problem for people who eat meat, either; alpha-gal is widely used in medicines and vaccinations (it makes them faster acting), with potentially devastating results if given to someone with the allergy.

“Recently I had a question from a patient who was snake handler in her spare time,” says Van Nunen. “She asked, ‘What happens if I’m bitten and need to have shot of antivenin?’ Anti-venins are made in mammals so we couldn’t guarantee the safety of her treatment.” Artificial blood, which is bovine based, may also prove fatal to the wrong patient.

“You look around and someone has invented something that could be a danger to one of our people. Science is moving so fast,” says Van Nunen. The organisation TiARA (Tick induced Allergies Research & Awareness), which she’s closely involved with, is working to increase knowledge among the public, the medical profes-sions and in those organisations whose employ-ees, such as council garden workers, are vulnerable to tick bites. People who live in tick-prone areas can also take their own precautions: wearing pro-tective clothing when in the garden, for instance, and learning to remove ticks properly.

There is also some evidence that if a person with MMA isn’t bitten by ticks again, the allergy may disappear. This has happened with one of Van Nunen’s patients who has moved out of Aus-tralia and now appears allergy free.

Joy, Janelle and Liam’s mother Suzie are hop-ing that with time their allergies too will fade. In the meantime, they do all they can to avoid being bitten. Whenever Joy goes to the weekender, she sprays her limbs with insect repellent and her clothes with Permoxin – a spray vets use on dogs. If she’s doing serious gardening or bush clearing she wears disposable all-in-one suits.

Janelle is just as careful, carrying an EpiPen – an emergency adrenaline shot – everywhere with her. But she also tries to take comfort from the positive health aspects of having a meat-free diet. And at least she can still drink red wine. ●

Cause and effect: entomologist Stephen Doggett; Joy Cowdery

Page 6 of 6




Documents

Weekend Australian - Ticks Story - Ministry of Health