Dogs, worms and long days in the home study

Each July since my graduation from vet school, I’ve been incredibly fortunate to volunteer with the West Arnhem Land Dog Health Program (WALDHeP).

Led by Professor Liz Tudor, the WALDHeP project, which I first wrote about in 2013, provides de-sexing, internal parasite and scabies treatment, and other veterinary services to dogs in remote Indigenous communities in West Arnhem Land, Australia. This involvement has given me opportunities to do great work with wonderful people in breathtakingly beautiful locations few get a chance to see.

Unfortunately, the COVID-19 pandemic will most likely put a stop to our plans for this year, as it has for almost all other remote Indigenous community veterinary work. While this may mean that several tens of thousands of dogs and cats won’t receive veterinary care this year, restricted access is a necessary step Aboriginal and Torres Strait Islander organisations have put in place to protect their communities. Higher rates of immunocompromise and chronic disease combined with reduced access to medical facilities needed for COVID-19 cases makes it an especially risky time for all remote communities.

We’re all heartbroken that we can’t deliver the program in 2020, as it’s our favourite fortnight of the year. I’m going a little stir-crazy spending so much time at home in the study, looking out my window onto the neighbours grey metal roof and the last of the autumn leaves clinging to the trees beyond. It’s a welcome distraction to look back at where this journey has taken me, what I’m up to now, and dream of the wide open spaces of Arnhem Land.

My veterinary degree has taken me to a great deal of interesting places, from the flood-irrigated dairy country of Northern Victoria, to James Herriot’s stomping ground in Yorkshire, the rolling hills of West Sussex and, of course, the majestic landscape of Arnhem Land. Through my volunteer work and a residency I undertook with the Melbourne Veterinary School, I’ve worked in over 10 different communities across Arnhem Land (an area almost half the size of Victoria), with many different languages or dialects, cultural histories, stories and practices.

I’ve gained a new appreciation for the great many ways dogs are significant within these communities: acting as companions or hunting partners, playing integral roles within the intricate kinship system, or even creating resources as critical as fresh water within dreaming stories. It has been a truly humbling experience to learn about these important roles and to share these experiences with the many other volunteer vets, final-year vet students and other volunteers. The communities we visit have been so welcoming, generous with their time and cultural teachings, and appreciative of the work that we do. I’m very proud to be part of the WALDHeP team.

Access to veterinary care is just one piece of the puzzle. The more I’ve been involved in remote community veterinary work, the more I’ve become interested in how we can do things better and how we can maximise our impact within a One Health framework. One Health is a fairly recent way of thinking in Western science, but a concept as old as time within the Indigenous knowledge sphere. At its heart, One Health is the notion that human, animal and environmental health are all interconnected, and that considering all of these areas together can lead to the formation of more effective disease control and prevention strategies. In Indigenous culture, the concept that the people, animals and the land are one is an intrinsic part of life. We can all learn a lot from First Nations People, both in Australia and overseas, in this regard.

This interest has led me to undertake a PhD with the Melbourne Veterinary School titled The effectiveness, feasibility and economic evaluation of canine deworming programs in reducing the prevalence and intensities of zoonotic ancylostomiasis and strongyloidiasis in Indigenous communities in Northern Australia.  That’s quite a mouthful, isn’t it?  I’ll elaborate…

There are a number of parasites capable of infecting dogs and people. These are known as zoonotic parasites, some examples of which are certain species of hookworm and threadworm. Hookworm and threadworm infections can have a range of symptoms in dogs and people, from mild to life-threatening, and have long been issues in Aboriginal communities across the north of Australia. There are several reasons for this.

Firstly, young worms live in the soil and infect their hosts by penetrating the skin and migrating through the body to the intestine. They thrive in warm and moist conditions, so the tropical climates up north are ideal. Secondly, these infections can have vague symptoms and are often slow or difficult to diagnose. Thirdly, there have been a range of efforts to rid communities of these parasites, but a lot have been ineffective and in many cases it’s unclear why. This is where my PhD comes in.

My research supervisor, Professor Rebecca Traub, has done a lot of work on zoonotic hookworms, showing that they are the second most common type of hookworm infection in people in the Asia-Pacific region. We suspect that dogs may play a role in infecting people with these parasites in Indigenous communities too, and that the large numbers of free-roaming dogs we see there may act as a reservoir of infection, contaminating the soil with worms when they defecate. If we only treat the people, we may not be stopping the source of infection – the dogs. If we consider the humans, the dogs and the environment, we may be able to come up with better ways to improve everyone’s health.

So, how to go about this? Well, firstly I’m performing surveys looking at how many animals harbour these parasites in several Indigenous communities. There’s very little information on this currently, so this is an important first step. To do this I collect some dog faeces, look at it under the microscope for worm eggs and then subject it to more sophisticated DNA analysis to see what species of worms are present. If they’re the same species that can infect humans, I will look more closely at the DNA sequence of the worms to see if they’re similar to the sequences we find in human infections. This provides evidence that there’s zoonotic spread occurring from animals to humans (or potentially vice versa).

Once we’ve established that the worms are present, the next step will be trialling a few different parasite treatments in dogs in Aboriginal and Torres Strait Islander communities to see which is best at reducing and eliminating worm infections in the dogs. Currently we use a couple of different parasite treatments in our veterinary work, but we don’t have much data on how effective they really are in this scenario and some treatments can only be given under veterinary supervision. We hope to determine which treatments are effective and economical in reducing dog (and in turn human) infections and can feasibly be given as a treatment by owners or as part of an ongoing One Health program driven by the community. A lot of great work is also being done by other members of my lab group in other countries in the Asia Pacific, establishing the importance of animal deworming as part of One Health programs. We hope that our work will inform best practice and encourage the adoption of a One Health approach in more health programs at local to global levels.

One Health is an exciting field of research to be involved in, the relevance of which continues to be demonstrated in events from zoonotic virus spread to climate change. My favourite part, however, is the connection I feel to my own Palawa heritage, the Aboriginal and Torres Strait Islander people I work with and the cultural background and understandings we share.

When it comes to One Health, we really are all in this together.

Banner image: Dr Cam Raw with other staff and Doctor of Veterinary Medicine students in West Arnhem Land.