Parasitic worms could be the solution to asthma, eczema and coeliac disease

by Nicky Pellegrino / 09 January, 2019
RelatedArticlesModule - Parasitic worms asthma coeliac disease

Photo/Getty Images

Being infected with intestinal worms may not sound like an attractive proposition. Soon, however, it may be the way we treat a range of allergies and autoimmune conditions such as asthma, eczema and coeliac disease. All are on the rise in developed countries, and the helminth, or parasitic worm, is believed to hold the key to why.

“There is a theory called the absent friends hypothesis,” says Kara Filbey, a researcher at Wellington’s Malaghan Institute. “Our immune systems evolved to have worms. We’re supposed to have some inside us, but now we’ve eradicated them completely in the Western world.”

To make a home inside the gut, worms need to be able to keep a lid on our immune system so it doesn’t attack them. Without them there to control the inflammatory response, the theory is that our system starts responding to things it shouldn’t, such as allergens in the environment.

“If you look at places where they do have worms endemically, such as Africa or Southeast Asia, they have a lower rate of allergies and inflammatory disease,” says Filbey.

She has been doing helminth research for a decade and is a bit of a fan. “Worms are amazing. They are big, multicellular organisms with their own microbiome and they have immune systems themselves, so they must be having a big effect on us.”

Research is taking place worldwide to discover exactly what effect parasitic worms are having, and how that might be used to benefit our health. Filbey’s latest project has proved they are not merely manipulating the immune system.

Kara Filbey. Photo/Supplied

She worked with mice, first giving them a dose of a type of gut worm that naturally infects rodents in the wild. “That worm is inducing immune responses, obviously, as it’s a foreign object, but you wouldn’t know the mouse had it,” she says. “Some of them actually look healthier, with nice, shiny fur.”

Next, Filbey gave the same mice hookworms, which enter through the skin and migrate via the lungs to the gut. A surprising thing happened. Rather than dampening the immune system, the original gut worm induced an immune response, activating cells that circulate around the body and lodge in different organs. The immune cells attacked and killed the hookworm while it was still in the lungs.

So Filbey’s results suggest that living with a “friendly parasite” could protect humans against infection as well as autoimmune diseases.

There is still work to be done before GPs can start prescribing worms. The correct dose of the right worm is vital – a heavy burden can have disastrous consequences, stunting growth or causing anaemia, and is particularly harmful for children and pregnant women.

We also need to come up with a more streamlined way of producing helminths. At present, larvae for clinical trials are collected from the faeces of infected human hosts, before being cleaned and given as a treatment.

Gut worms can ward off hookworms. Photo/Supplied

Some people are not prepared to wait until worm therapy is mainstream. Desperate for relief from a variety of conditions, including lupus and irritable bowel disease, they are buying worms online and self-infecting.

Ultimately, the aim is to pinpoint exactly how worms are protecting us. It may be they are secreting a molecule that can be delivered in the form of a pill or vaccine. “But it may be the worm’s microbiome doing the job, not the actual worm,” says Filbey. “We don’t know yet.”

Her latest work focuses on how worm infections can reduce inflammatory skin diseases such as dermatitis. So far, results are looking good.

“Atopic dermatitis and eczema is the first allergic disease you see early on in life. People then go on to develop other allergic diseases such as hayfever, food allergy and asthma. This is called the allergic march.

“We think when your skin is damaged at that early stage, allergens are able to sensitise your immune system and prime it to have an inflammatory response later on when you ingest that allergen or breathe it in. If we can target dermatitis and that early skin barrier dysfunction, then maybe we could stop the whole allergic cascade throughout your life from happening.”

This article was first published in the December 22, 2018 issue of the New Zealand Listener.

Latest

Acclaimed writer Greg McGee on his family's stolen children
108138 2019-07-13 00:00:00Z History

Acclaimed writer Greg McGee on his family's stolen…

by Clare de Lore

Greg McGee always knew his great-grandfather had kidnapped his father and uncles as infants, but now for the first time he’s revealing that...

Read more
Video-streaming platforms are failing their impaired customers
108303 2019-07-13 00:00:00Z Tech

Video-streaming platforms are failing their impair…

by Peter Griffin

When it comes to video streaming, the hearing- and visually impaired can only dream about the technology that’s passing them by.

Read more
We like big vehicles and we cannot lie
108312 2019-07-12 00:00:00Z Politics

We like big vehicles and we cannot lie

by The Listener

It would take a psychologist to explain Kiwis’ love for utes and SUVs. But it’s not the only reason people are revved up over the attempt to reduce...

Read more
Booker winner Arundhati Roy on democracy in peril
108043 2019-07-12 00:00:00Z Profiles

Booker winner Arundhati Roy on democracy in peril

by Sally Blundell

Soon to speak in New Zealand, Booker Prize winner Arundhati Roy discusses her complex relationship with her native India with Sally Blundell.

Read more
Girl: A powerful drama about a trans teen with dancing dreams
108346 2019-07-12 00:00:00Z Movies

Girl: A powerful drama about a trans teen with dan…

by James Robins

Belgian film Girl follows the anxious life of a transgender ballerina as she transitions.

Read more
There are many causes of mouth ulcers – and the solutions are just as varied
107588 2019-07-12 00:00:00Z Nutrition

There are many causes of mouth ulcers – and the so…

by Jennifer Bowden

A readers asks, "I’ve experienced mouth ulcers in the past and found they came when I hadn’t been eating much red meat. Why is that?"

Read more
When Sir Bob Jones once put himself at risk of becoming the Prime Minister of NZ
108045 2019-07-11 00:00:00Z History

When Sir Bob Jones once put himself at risk of bec…

by Paul Little

Many people will have forgotten Sir Bob Jones once put himself at risk of becoming the Prime Minister of New Zealand.

Read more
The mountaineer who overcame a near-death experience to blaze a trail for women
108038 2019-07-11 00:00:00Z Profiles

The mountaineer who overcame a near-death experien…

by Poppie Johnson

The road has sometimes been rocky for this humble mountaineer, but Morris is quietly blazing a trail for a new generation of “girl guides”.

Read more