Dr Anna Okello - Research Program Manager Livestock Systems talks about the importance of One Health
What is One Health and why is this approach more important than ever in a COVID-19 world?
One Health recognises that the health of humans, animals and our environment are all inter-connected. One Health promotes a collaborative, multi-sectoral and transdisciplinary approach to ensure the health of humans, animals and our environment, recognising that the health of one depends on the health of the other two. From a public health perspective, One Health acknowledges that you cannot achieve optimal health of the global human population if, for example our agrifood systems are broken, our environment is polluted, or veterinary systems and services are not adequately resourced to control animal disease and ensure the safety of our food that comes from them.
One Health is important at this time of COVID-19 because a joined up, holistic approach is required to address these important but increasingly complex issues in the 21st century; the global human population will never be health secure if we are not food secure, and we will never be food secure if our broader environment is not functioning optimally – this is the essence of One Health.
What is the connection between COVID-19 and animals?
You can look at the connection between COVID-19 and animals in a number of ways. In the first instance, COVID-19 has likely emerged from what we call a disease spill-over event from animals to humans - the current research is pointing to strong ‘genetic clues’ that COVID-19 originated in bats.
This is not surprising to the global health community - there are thought to be hundreds of coronaviruses, and a number of these can be found in bats. In fact we don’t need to look very far back in history to see a similar disease spill-over event caused by a coronavirus – Severe Acute Respiratory Syndrome or SARS - was also found to have originated in bats; in this case the civet cat was the intermediate host, however we don’t yet know what this is for COVID-19
We must remember that humans have lived alongside animals for thousands of years; sharing of our space with animals leads to sharing of our diseases with them and vice versa. It’s thought over 60% of the total number of diseases that infect humans come from animals, however in terms of NEW diseases this figure jumps to an estimated 75% - that is, it’s more than 75% likely that a new disease of humans that we haven’t ever seen before – such as COVID-19 – has originated in animals.
What are the implications of the COVID-19 situation for wet markets?
There has been a lot of focus in recent weeks on the role of wet markets in the COVID-19 outbreak and rightly so. This is not surprising to many of us working in this area – the risks of disease emergence in humans as a result of mixing of animal species, and the subsequent handling and consumption of animal source foods are well documented.
However, not all wet markets are equal, and by extension, not all risks associated with wet markets are equal. There are differences between well-regulated, hygienic wet/informal markets that for example, separate animal species, separate meat and vegetable sections, where vendors regularly clean hands, knives, boards etc – and those that don’t.
There are also differences between the largely ‘wildlife’ markets, where the products are often sold for medicinal or other socio-cultural purposes, compared to those markets contributing to the food security to large numbers of people.
From a research perspective, the emphasis needs to firstly be on quantifying and really understanding the risks – which is difficult in the case of COVID-19 where the disease transmission pathway, particularly in terms of the intermediate host, is not yet clear.
We also need to remember that despite the risks of wet markets – both real and perceived – simply shutting them down could result in potential rebound negative impacts ranging from food insecurity, to higher costs of food resulting from longer value chains and associated increased packaging and refrigeration, to the driving of wildlife trade underground. Many experts believe the focus should instead be on upgrading and regulating markets – including better resourcing the public veterinary services that have a stake in meat inspection and food safety – rather than simply closing them down.
How is ACIAR currently addressing the threats to food security from zoonotic diseases?
Many diseases are passed to humans from animals through the handling, preparation and consumption of animal products, and there are strong gender implications to known risk factors.
ACIAR has a long history of funding projects in a number of these areas; for example we have been funding the International Livestock Research Institute to undertake research in wet markets in Vietnam for much of the last decade. A large part of this research is to really quantify the risk of foodborne disease such as Salmonella in wet markets in order to make robust policy recommendations on how to improve these market systems based on what the risk profile actually is - which is a key priority for the Government of Vietnam.
ACIAR has also funded several years of research in Lao PDR looking at parasitic food-borne disease such as the Taenia solium tapeworm people can get from eating raw or under-cooked pork; this leads to a debilitating disease in humans called neurocysticercosis; the number one cause of acquired epilepsy in LMICs.
Another example of ACIAR-funded research in this area is in Timor-Leste, where researchers from the Australian National University are looking at the potential linkages between chronic infection of Campylobacter in childhood – as a result of environmental contamination from chickens - and childhood stunting and malnutrition as a result of chronic damage to the small intestine. This is another great example of the linkages between food security and human health that we are addressing at ACIAR through a One Health approach.
Moving forwards into a post-COVID-19 scenario, what do you think are the key areas for future research from a One Health perspective?
Whilst the concept of One Health has enjoyed a growing following particularly in the global public health sector in the last 15 years or so, examples of its operationalisation – especially outside an emergency response scenario – is still lacking.
One Health approaches in many countries start on an unequal footing; there is a very real imbalance of funding and prioritisation given to veterinary services compared to human health services in most parts of the world – particularly those aspects that deliver and oversee public veterinary goods and services that are essential to human health, such as abattoir inspection, food safety and the surveillance and control of zoonotic diseases.
While the case for more biophysical research into the epidemiology, risk factors, diagnostics and prevention of zoonotic disease is still required, the focus should also be on a much larger body of research that looks more into the operationalisation and governance aspects of One Health research that can help move One Health from essentially being a “nice idea” to it being the underlying force and driver of policy and programmatic decisions around how we produce food and manage our environment in a way that optimises human health and nutritional security across the world.
If One Health becomes ‘part of everyday life’ it will enable us to better identify and prevent risk of spillover events, whilst at the same time strengthening the systems that simultaneously keep us safe from disease and provide our food.
ACIAR currently funds a One Health research program in partnership with the DFAT Indo-Pacific Centre for Health Security that is looking at a number of these broader policy, governance and economic aspects of One Health through a range of projects including veterinary legislation in Cambodia, Anti-microbial resistance in Fiji and the risk factors of zoonotic vector-borne disease transmission in Papua New Guinea and Indonesia.