Experts have warned that the COVID-19 pandemic might just be one in a series of increasingly frequent viral outbreaks, as the human species enters what they describe as “a pandemic era”.
Anthony Fauci, leading US immunologist and director of the National Institute of Allergy and Infectious Diseases (NIAID), and David Morens, a medical epidemiologist at NIAID, predict that widespread outbreaks of diseases and epidemics will only accelerate over the coming years as populations grow, societies expand and deforestation increases.
As part of research published last month in scientific journal Cell, Fauci and Morens point out that “the past decade has witnessed unprecedented pandemic explosions”—citing swine flu, Zika virus and Ebola fever—and suggest that “COVID-19, recognized in late 2019, is but the latest example of an unexpected, novel, and devastating pandemic disease.”
“One can conclude from this recent experience that we have entered a pandemic era,” they state. “The causes of this new and dangerous situation are multifaceted, complex, and deserving of serious examination.”
Fauci and Morens explain that although newly emerging infectious diseases have been threatening humans since the Neolithic Revolution some 12,000 years ago—when hunter-gatherers settled into villages to domesticate animals and cultivate crops—the past decade has seen a sharp spike in the number of novel coronavirus outbreaks after more than a century without them.
Most of these viruses are, and historically have been, zoonotic—that is, originating in a non-human animal—spreading to humans via a process known as “host switching”. And some of the most prevalent factors contributing to this spread have to do with human behaviour.
Population growth, crowding, human movement, and other behaviors that either “perturb the environment or result in new human-created ecologic niches” all contribute to the emergence and transmission of infectious diseases—a problem for a species so engaged in globalisation and societal growth. Fauci and Morens stress that “the more populous and crowded we as a species become, and the more we travel, the more we provide opportunities for emerging diseases.”
Environmental factors such as water storage, land clearing and wet markets with poultry and other potentially infectious animals all similarly contribute to the risk of viral outbreaks—adding further weight to what Fauci and Morens describe as “a powerful argument that human activities and practices have become the key determinant of disease emergence.”
If these practices continue, they conclude, it’s likely that “COVID-19 [is] only the latest examples of a deadly barrage of coming coronavirus and other emergences [of infectious diseases].”
James Gilkerson, Professor of Veterinary Microbiology at the University of Melbourne, echoed these concerns.
Speaking to VICE News via text message, he explained that “[while] we have always had epidemics and plagues, it is the massive increase in population mobility that has led to an increased risk. Combined with habitat destruction and humans using more of the planet for living space, these three things will increase risk of future pandemics.”
Professor Gilkerson said he hopes societies will be able to learn from the COVID-19 pandemic about how to best minimise the spread of future diseases, while developing antibiotics, antivirals and vaccines to mitigate the risk.
Fauci and Morens warn, however, that unless humans make significant changes to their behaviour as a species, more deadly outbreaks like that of SARS-CoV-2 will almost inevitably continue to happen.
“As human societies grow in size and complexity, we create an endless variety of opportunities for genetically unstable infectious agents to emerge into the unfilled ecologic niches we continue to create,” they write. “There is nothing new about this situation, except that we now live in a human-dominated world in which our increasingly extreme alterations of the environment induce increasingly extreme backlashes from nature.
“There is no reason to think that [life-saving drugs and vaccines] alone can overcome the threat of ever more frequent and deadly emergences of infectious diseases,” they add. “The COVID-19 pandemic is yet another reminder ... that in a human-dominated world, in which our human activities represent aggressive, damaging, and unbalanced interactions with nature, we will increasingly provoke new disease emergences.
“We remain at risk for the foreseeable future.”
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