Rather than waiting for the next pandemic to arrive... then struggle to limit its spread, search for treatments, and race to develop a vaccine to protect ourselves, we need to become proactive. If we can discover how pandemics start and change these factors, perhaps we can prevent them from occurring. Given the loss of lives and freedoms, and the devastation of the global economy we are seeing with COVID-19, this seems a much better strategy than reacting after another one starts.
Essentially all pandemics originate from the diverse microbes carried by animals. When we interact with these animals, the microbes they carry can jump to humans and we often have no resistance to these new organisms. Changes in human activity that increase contact with animals create an increased chance of this happening and therefore an increase in the risk of creating a pandemic. Interestingly, the underlying causes of pandemics are environmental changes, the same ones that cause loss of biodiversity and climate change, say a panel of health and environmental experts.
The IPBES (Intergovernmental Platform on Biodiversity and Ecosystem Services) held a workshop in July 2020 with 22 experts from around the world to discuss these causes and what could be done. Their goals were to investigate and discuss:
How pandemics emerge from nature,
The role of land-use change and climate change in driving pandemics,
The role of wildlife trade in driving pandemics,
Learning to better control pandemics, and
Preventing pandemics based on a “One Health” approach.
So, what are we doing that increases our risk?
Intensification of agriculture and factory farms with animals being raised in restricted quarters bring animals and people into closer contact, enhancing the sharing of microbes. Recent reports of COVID-19 infection and mutation of the virus in a population of farmed mink in Denmark have alerted us that infections are spread in both directions between animals and people.
Exponential rise in consumption and trade of animals in recent decades, further driven by developing nations adopting our consumption habits, has opened new pools of animal-borne diseases to the world stage. Global travel, even for retired folks like me, helps to carry infectious organisms from one part of the world to another quickly, once a disease is established. In 1918 it was a war that caused people to travel, carrying the deadly virus, but today we travel for pleasure and business, and just to get away from cold winters!
This pandemic has also underlined some poor strategies we’ve chosen in the past. Crowding in large nursing homes allows diseases to spread easily through a vulnerable population. Already one Canadian province has decided to limit the number of seniors who can be cared for on one institution, and they were quick to limit caregivers to one home to prevent workers from carrying organisms from one institution to another.
Basic healthcare is also less available to some minorities, resulting in more cases and worse outcomes in this pandemic. Some occupations, like cashiers and bus drivers, cause workers to be more easily exposed to infectious diseases carried by others. Keeping everyone healthy and protected from infectious diseases, within our own countries as well as around the world, helps us all resist infections that could become a pandemic. As long as the infection exists somewhere in the world, there is the possibility of it spreading to us again even after we have eliminated it here.
Pandemics come from nature
The majority of new diseases (70%), such as Ebola, Zika, and Nipah encephalitis, and almost all pandemics, like influenza, HIV/AIDS, SARS, and COVID-19, are zoonoses – caused by microbes that originated in animals and “spilled over” into humans through contact between wildlife, livestock and people.
Scientists estimate there are about 1.7 million unknown viruses in mammals and birds, and that as many as 850,000 of these could have the ability to infect humans. That’s a lot of potential for pandemics in the future. It is believed the riskiest sources are mammals (especially bats, rodents, and primates) and some birds (particularly water birds) as well as livestock (for example, pigs, camels, and poultry).
Land use change
Activities and changes in land use that bring humans closer to the natural habitat of wild animals is another factor. As humans invade their natural habitats, wildlife are forced to move, increasing and changing their contact with other species as well as humans, and creating opportunities for viral spread and mutations. Changes in the use of land that pressure wildlife habitats are believed to cause at least 30% of new diseases. When viruses jump to a new species, mutations are more common as they adapt to their new environment.
Land-use change includes deforestation, building homes in wildlife habitats, expansion of crop and livestock production areas, and urbanization, the process by which more and more people leave rural areas and move into cities.
The potential to affect human health is mostly ignored when land planning decisions are made. We just learned that a developer has bought a tract of land next to us that runs through a forested area, a wetland, and to the beach and is planning a housing development. We see deer in there often as well as blue herons, geese, ducks and fox. I’m wondering if the bald eagles we often see are nesting in those trees, and if anyone has thought to investigate the plant and animal life it supports. We have regular visits from raccoons and, while not my favourite critters, they are part of the ecology here. If these animals and some of the diverse species that live in the wetland are displaced, will that affect our environment and our health too?
Trade and consumption of wildlife
I was surprised to read that legal wildlife trade has increased 5-fold in the last 14 years, and there is a significant illegal trade as well. Many of these animals are bought for pets, leading to the introduction of new zoonoses like monkeypox. Wildlife are being farmed in some countries for this purpose. Trade in mammals and birds is particularly risky, as they are important reservoirs of potential human diseases.
Regulations that control this trade are limited, spread among numerous authorities, and inconsistently enforced or applied, according to the report of the IPBES described earlier.
How often do diseases jump to humans?
More than five new diseases emerge in people every year, and any one of these has the potential to spread and become a serious pandemic. For this to happen, it simply needs to be an organism that causes severe disease plus one that also spreads easily, often through the air.
What can we do to prevent the next pandemic? And can we afford it?
Global strategies to prevent pandemics based on reducing wildlife trade, decreasing land use change, and increasing health surveillance are estimated to cost between US$40 and 58 billion annually, 100 times less than the cost of a pandemic. So, yes, it’s affordable. With the economic impact of the current pandemic, I’d say we can’t afford not to do this…
According to the report prepared by experts at the IPBES Workshop on Biodiversity and Pandemics, pandemic prevention strategies could include:
Assessing the health impact of pandemic and emerging disease risk from major development and land-use projects before beginning the project.
Reforming financial aid for land use so benefits and risks to biodiversity and health are recognized and targeted.
Assessing effectiveness of habitat conservation measures, including protected areas and habitat restoration programs that can reduce pandemics.
Promoting changes that will reduce the types of consumption, globalized agriculture expansion and trade that have led to pandemics. Examples are consumption of palm oil, exotic wood, products that require mining, transportation infrastructure, meat and other products of globalized livestock production. This could include taxes, levies or quotas on meat consumption, livestock production or other forms of high pendemic risk consumption.
Building partnerships to reduce zoonotic disease risks in international wildlife trade.
Educating communities in infectious disease hotspots regarding the health risks associated with wildlife use and trade known to cause a pandemic risk.
Restricting wildlife species that are identified by experts as high-risk sources of human disease, testing effectiveness of market cleaning protocols, and using refrigeration more effectively in markets.
Conducting disease surveillance of wildlife in the trade, and in wildlife hunters, farmers, and traders.
Improving law enforcement on all aspects of illegal wildlife trade.
Supporting “One Health”, scientific research to design and test better strategies to prevent pandemics. One Health is an approach that recognizes that the health of people is closely connected to the health of animals and our shared environment. It is a collaboration between health sectors and disciplines working at local, regional, national, and global levels, with the goal of achieving optimal health outcomes for all.
As a society, we can contribute too. Education about the issues and ways we can change what we do, to reduce the risk of future pandemics and their origins, is important, especially for the younger generation. We can transition to healthier and more sustainable and diverse diets, including responsible amounts of meat, especially from wildlife sources. We can encourage and support incentives for companies to avoid land-use changes that increase pandemic risk, and avoid buying products from unsustainable trade or wildlife farming with increased disease risk. And we can pressure our governments to act on recommendations like those described above.
While we are hearing positive news about COVID-19 vaccine development, unfortunately many more will die from COVID-19 before enough can be manufactured, distributed, and administered to stop its spread. While we continue our actions to limit the spread of this virus, we need to consider what we and our governments can do to prevent the next pandemic that undoubtedly will emerge all too soon.
References:
International report lays out plan to ‘escape from the pandemic era’ – Medical News Today
Workshop Report on Biodiversity and Pandemics of the IPBES – Zenodo
People started coronavirus back-and-forth on mink farms, Dutch study says - CNN
One Health – Centers for Disease Control and Prevention
From the plague to MERS: A brief history of pandemics – Aljazeera
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