I recently had a conversation with some friends about the strangeness of life during the Covid-19 pandemic five years ago. We all agreed that it seemed more recent than it was and that our lives felt divided into a pre and post pandemic era. We also spoke about the fear of another pandemic happening in our lifetime and how Covid was an example of a zoonotic disease (a disease caused by a pathogen that originates in animals and jumps to humans) that got us onto the topic of how humans and animals share the land.  

By way of coincidence, shortly after that conversation I began working on a project with my colleague Laetitia Osborne, a geospatial expert at WWF. She had been collecting data from communities in very remote villages in the mountainous landscapes of the Eastern Cape, and when we spoke about water collection, it painted the perfect example of how humans, animals and nature are all interdependent and how the health of one depends on the health of the others.

She explained to me that “the communities are dependent on nature to access water for drinking and for sanitation, as well as relying on the same rivers and springs for their livestock.”

This, she says, “reveals the deep connection between people, animals and nature.” 

On a global scale in our industrialised world, human activities, from expanding urbanisation to intensified agriculture, are bringing more people into closer contact with animals, increasing the likelihood of pathogens jumping species and resulting in zoonotic diseases. These diseases can be transmitted between animals and humans through direct contact, food, water or the environment. 

Laetitia and I got chatting about the One Health concept, an approach that she says underpins her work in the Eastern Cape and which is founded on this idea that human, animal and environmental health are all linked, and we cannot simply focus on the one at the expense of the other.

I will share more about the excellent work that Laetitia and other colleagues are doing (see below), but I first wanted to explain more about this fascinating approach to health. 

Here are six questions and answers to help us understand the approach and why it is so crucially important:

A spillover event is when a pathogen (such as a virus, bacteria or parasite) jumps from an animal host to humans, and experts warn future zoonotic diseases could be even worse than Covid. The more we disturb animals’ natural habitats, disrupt ecosystems and induce climate change, the higher chance there is of more such events. 

The University of Pretoria’s Professor Wanda Markotter, a global expert on zoonotic diseases, explains the dire impact of human activities on disturbing ecosystems and causing more spillover events. “This includes land use changes, agriculture intensification, urbanisation, climate change, international travel and trade, and wildlife consumption to name a few.” The World Health Organization (WHO) adds to that list “extractive industries, climate change, animal trade and encroachment into wild areas.”

According to the WHO, Covid killed at least 7 million people though likely far more. Covid spread very easily but did not have as high a mortality rate as other zoonotic diseases like Ebola which kills up to 90% of people who get infected. A disease that spreads as quickly as Covid and kills as readily as Ebola would be catastrophic. 

The WHO reports that over 30 new diseases in humans have been detected in the last three decades, and three quarters of those (75%) are zoonotic (originated in animals). Added to this is the fact that the rise of drug-resistant infections in animals and humans could make future zoonotic diseases harder to treat.

In addition to the stressors mentioned above, the influence of climate change is also playing a major role. For example, in some places, climate change brings increased variability and rainfall intensity allowing disease-carrying insects – like mosquitoes – to breed faster and thrive in new regions. Floods and storms can contaminate water supplies by washing harmful pollutants like sewage, chemicals and debris into water sources and damaging water treatment infrastructure. This contamination can trigger outbreaks of diseases like cholera and dysentery, while warmer temperatures may alter animal migration and behavior, accelerating pathogen transmission. Higher temperatures can also accelerate migration rates in viruses and bacteria, potentially enhancing their resistance or transmissibility.

One Health is the most promising approach to these issues. The term was coined in 2004 and was later adopted by the WHO and other global agencies, so it predated the Covid pandemic but was strongly accelerated by it. Markotter says that through zoonotic diseases like Covid, “We realised the interconnectedness of human, animal and environmental health and that we cannot take a siloed approach to diseases going forward. We need to understand what drives spillover of diseases from animal sources and identify interventions that will work, and we need to do this together with communities and policymakers.”

Because it is a global approach that recognises the interconnectedness of human, animal and environmental health, and provides a framework in which all three can be protected simultaneously, it means people from different disciplines must work together towards a common goal. Says Markotter, “A collaborative, inter- and trans-disciplinary approach (One Health) is crucial to understand this interconnectedness and to design mitigation and interventions that will reduce risk.”  

The work that Laetitia and other colleagues are doing at WWF highlights how important it is to take humans, animals and nature into consideration for the health of all. Policy can bring about real change, but it takes time for its effects to reach all corners of the country. Laetitia says that this is particularly true in remote rural areas where “a lack of an integrated policy approach to health, water and food is more pronounced.” 

These areas are “highly biodiverse and play an important role in harbouring the natural resources, such as some of our major rivers, that we all depend on for health, fresh water and food production.” 

That is why Laetitia has been collecting data from local farmers in the small villages of Upper Tsitsana, Mabua and Madlangana in the Eastern Cape. It is part of a WWF project to assess the impacts of climate change and biodiversity on food production and vice versa. 

Laetitia explains that in the Eastern Cape, natural freshwater springs emerge from rocky outcrops and water can be collected from the “eye” of the spring which themselves form meandering streams that carve through valleys, sustaining people, livestock and wildlife.  

She says that while free-flowing water provides a lifeline, it also comes with challenges in some of the villages. Animals and humans rely on the same sources, increasing the risk of contamination and depletion.  

Therefore, “protecting these springs offers a sustainable solution.” 

Work already done by WWF and partners shows the value of this: in another area of the Eastern Cape, 18 springs were selected and secured for protection and through that, 1 412 households now receive reliable access to safe drinking water while 130 temporary jobs were created during local spring protection. Forty thousand rural dwellers in the area now have access to potable water less than a kilometre from their homes, and the average cost per spring site development was only R150 000. 

Laetitia says that by protecting vital water sources through simple principles like controlled access points, natural filtration with vegetation and community-led stewardship, clean reliable water is secured for people, ecosystems and animals alike. 

“Balancing access while preserving these natural sources is key to a thriving One Health approach, where water security benefits all,” she says.