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Jeffrey Gogo Climate Story

Several months before the coronavirus (Covid – 19) outbreak in China last November, scientists at Auburn University published research that hypothesised the relationship between biodiversity loss (and by extension climate change) and the global emergency of infectious diseases.

In the study titled, ‘The Coevolution Effect as a Driver of Spillover’, the researchers found “that as humans alter the landscape through habitat loss, forest fragments act as islands, and the wildlife hosts disease-causing microbes that live within them undergo rapid diversification.”

They observed that “across a fragmented landscape we would then see an increase in diversity of disease-causing microbes, increasing the probability that any one of these microbes may spill over into human populations, leading to outbreaks.”

The coevolution effect, as developed by the Auburn University scientists, is premised on “ecology and evolutionary biology, to explain the underlying mechanisms that drive this association.”

Worldwide, scientists are agreed that infectious diseases such as SARS, Ebola, Zika, West Nike virus and others are zoonotic — meaning they spread from animals to humans.

In the same context, the novel pneumonia Covid-19, which has killed about 8 000 people throughout the world, has its origins in wildlife, mainly the eating of bats by humans, even though the Malayan pangolin, illegally imported into China’s Guangdong province, contains coronaviruses similar to Covid-19. That’s the first assumption.

The second is that a progenitor of Covid -19 jumped into humans, acquiring certain features through adaptation during undetected human-to-human transmission.

Once acquired, say researchers, these adaptations enabled “the pandemic to take off and produce a sufficiently large cluster of cases to trigger the surveillance system that detected it.”

But there’s something noteworthy that these findings put to rest — the countless conspiracy theories around the origins of Covid-19, which started in Wuhan, Hubei province, China, infecting hundreds of thousands of people around the world and forcing the global economy into a tailspin.

Scientists conclude that the virus “is not a laboratory construct or a purposefully manipulated virus,” according to a research note by a group of researchers in the scientific journal Nature Medicine, published March 17.

An even more interesting aspect is how deadly viral outbreaks such as Covid-19 could be influenced, now and in the future, by climate change and other factors such as destruction of environmental habitats, —industrial agriculture and rapid urbanisation.

Harare-based climate expert professor Kenneth Odero told The Herald Finance & Business that the outbreak of infectious viruses and other pathogens have been associated with disruptions to habitats and climates caused by human activity in farming, transportation, mining and others.

“Human activities, broadly speaking, are (cumulatively) the drivers of anthropogenic climate change,” Prof Odero explained.

“The latter invariably puts pressure on wild animals and birds, whose survival and adaptation instinct often leads to migration. The outbreak of diseases in both animals and humans has been linked to such migration,” he added.

In disease ecology, the dilution effect hypothesis is heavily relied upon.

Released early in the 21st century, the hypothesis is built around the idea that “biodiversity conservation can protect humans from emerging infectious diseases.”

The Nature Medicine scientist said “the dilution effect highlights the critical role that wildlife conservation can play in protecting human health and has transformed the understanding of zoonotic infectious diseases.”

Indeed, it is crucial for humanity to address as a matter of urgency the multiple threats from cross-cutting issues such as climate change, deforestation and biodiversity loss.

“Humans and nature are of one connected system, and nature provides the food, medicine, water, clean air and many other benefits that have allowed people to thrive,” said Doreen Robinson, chief of wildlife at the United Nations Environment Programme (UNEP), in article on the agency’s website.

“Yet like all systems, we need to understand how it works so that we don’t push things too far and face increasingly negative consequences.”

According to UNEP’s Frontiers 2016 Report on Emerging Issues of Environment Concern, diseases transmitted from wildlife to humans threaten the entire fabric of social and economic development as well as ecosystem integrity.

In the last 20 years, says the report, emerging diseases have had direct costs of more than US$100 billion, “with that figure jumping to several trillion dollars if the outbreaks had become human pandemics.”

God is faithful.

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