What will cause the next pandemic?
We’ve now emerged from three years of the COVID-19 pandemic, having experienced global impacts far greater than global leaders ever imagined. When I worked with the World Health Organization (WHO), we were preparing for what they called Disease ‘X’, the name that identified a high-risk pathogen that we were yet to discover or experience, be it naturally or deliberately emerging. Yet, the world was gravely under-prepared with COVID-19 struck.
The hindsight we’ve gained and the lessons we’ve discovered affect every organisation and community. The important thing to understand is that it won’t be the last pandemic, and we need to better understand the reasons why.
The causes of the next pandemic are multifaceted and stem from various factors. While it is impossible to predict the specific circumstances surrounding the next pandemic, several factors contribute to the emergence and spread of infectious diseases.
1. Zoonotic Disease transmission: Many pandemics originate from zoonotic diseases, which are infections that can jump from animals to humans. These diseases typically emerge when humans come into close contact with animals, either through direct contact or through the consumption of animal products. Factors such as deforestation, urbanisation, and the wildlife trade can disrupt ecosystems and increase the likelihood of zoonotic spill over events. In fact, 6 out of every 10 human infectious diseases are zoonotic.
2. Encroachment into Natural Habitats: As human populations expand and industries exploit new territories, humans are increasingly encroaching into previously undisturbed natural habitats. This encroachment disrupts ecosystems and brings humans into closer proximity to wildlife, increasing the risk of exposure to novel pathogens. Deforestation, agricultural expansion, and urban development can lead to the displacement and mixing of wildlife, domestic animals, and humans, facilitating the transmission of diseases. Examples include the 2012 MERS-CoV outbreak in Saudi Arabia, the 2014 Ebola outbreak in West Africa, and the more recent COVID-19 pandemic. Scarily, continued deforestation in Brazil places it at the epicentre of the next pandemic potential, due to the destruction of large bat populations.
3. Global Travel and Trade: The increasing interconnectedness of our world through global travel and trade has accelerated the spread of infectious diseases. A virus that emerges in one part of the world can quickly reach distant locations within hours. International travel allows pathogens to move across borders swiftly, making containment efforts more challenging. The globalisation of trade can also facilitate the rapid movement of infected animals, animal products, and vectors, contributing to the spread of diseases.
4. Climate Change and Environmental Factors: Climate change and environmental disruptions play a role in the emergence and spread of infectious diseases. Altered rainfall patterns, rising temperatures, and ecological disturbances can impact the distribution and behaviour of disease vectors. Changes in vector habitats and behaviours can expand the geographic range of vector-borne diseases. Examples include an array of mosquito-borne diseases like Zika and Japanese encephalitis virus spreading out of their geographic distribution. Additionally, extreme weather events and natural disasters can create conditions conducive to disease transmission and disrupt healthcare systems.
Another example is the suspected adaptation of deadly fungi to higher temperatures, making them more transmissible to humans.
5. Antibiotic Resistance: The misuse and overuse of antibiotics in humans and animals have led to the emergence of antibiotic-resistant bacteria, often referred to as "superbugs." These resistant pathogens pose a significant threat, as they can cause infections that are difficult to treat with available antibiotics. Novel or mutating bacterial outbreaks could further complicate efforts to control and treat the disease.
6. Globalisation and Urbanisation: The rapid pace of globalisation and urbanisation has created densely populated areas where infectious diseases can spread quickly. Urban centres with inadequate sanitation, overcrowding, and limited access to healthcare can become breeding grounds for the transmission of diseases. The close proximity between humans and animals in urban settings, such as live animal markets and combined human / animal housing, can also facilitate the transmission of zoonotic diseases.
Addressing the causes of the next pandemic requires a comprehensive approach. This includes investing in robust public health systems, promoting sustainable land use practices, preserving natural habitats, regulating the wildlife trade, promoting responsible antibiotic use, and mitigating the effects of climate change. International cooperation, surveillance, and research are essential to monitor and respond to emerging infectious diseases effectively. Ultimately, proactive measures and a One Health approach, which recognises the interconnection between human, animal, and environmental health, are crucial in preventing and mitigating future pandemics.
How well prepared is your organisation for the next pandemic?