CIMMYT Senior Scientist Dave Hodson is a guest on Plantopia, a podcast produced by Cornell University that explains how protecting plant health can ensure a sustainable future. On the “Arms Race Part 1: Ug99” episode, Hodson discusses the striking parallels between wheat rusts and global pandemics in humans, pointing out that in both cases, we’re just one step ahead of the pathogen.
This story by Mike Listman was originally posted on the CIMMYT website.
Alarmed by the risk of global and regional food shortages triggered by the COVID-19 pandemic, a coalition of businesses, farmers’ groups, industry, non-governmental organizations, and academia has called on world leaders urgently to maintain open trade of their surplus food products.
Published by the Food and Land Use Coalition (FOLU) on April 9, 2020, and signed by 60 experts, the call to action urges world leaders to keep food supplies flowing, specially support vulnerable people, and finance sustainable, resilient food systems.
Covered by major world media, the declaration encourages governments to treat food production, processing, and distribution as an essential sector — similar to public health care — and thus to support continued, safe, and healthy activities by farmers and others who contribute to the sector, according to Martin Kropff, director general of the International Maize and Wheat Improvement Center (CIMMYT) and a signatory of the call to action.
“Consumers in low-income countries face the greatest threat of food insecurity,” said Kropff. “Their tenuous access to nutritious food is jeopardized when surplus food-producing nations choose to close trade as a defensive measure.”
Kropff added that many households in low-income countries depend on agriculture or related activities for their food and livelihoods. Their productivity and food security are compromised by illness or restrictions on movement or working.
“The call to action resonates with the findings of a landmark 2015 study by Lloyd’s of London,” he explained. “That work highlighted the fragility of global food systems in the event of coinciding shocks, an outcome that seems entirely possible now, given the health, cultural, and economic impacts of the COVID-19 pandemic.”
At the same time, the work of CIMMYT, other CGIAR centers, and their partners worldwide helps to stabilize food systems, according to Kropff.
“Our research outputs include high-yielding, climate-resilient crop varieties and more productive, profitable and sustainable farming methods,” he said. “These give farmers — and especially smallholders — the ingredients for more efficient and effective farming. They are grounded in reality through feedback from farmers and local partners, as well as socioeconomic studies on markets and value chains for food production, processing, and distribution.”
Experts share their insights on the link between biodiversity loss and emerging infectious diseases.
This story by Alison Doody was originally posted on the website of the International Maize and Wheat Improvement Center (CIMMYT). The views and opinions expressed are those of the authors and do not necessarily reflect the official policy or position of CIMMYT.
While the world’s attention is focused on controlling COVID-19, evidence points at the biodiversity crisis as a leading factor in its emergence. At first glance, the two issues might seem unrelated, but disease outbreaks and degraded ecosystems are deeply connected. Frédéric Baudron, systems agronomist at the International Maize and Wheat Improvement Center (CIMMYT) and Florian Liégeois, virologist at the Institut de Recherche pour le Développement (IRD) share their insights on the current COVID-19 crisis and the link between biodiversity loss and emerging infectious diseases.
What trends are we seeing with infectious diseases like COVID-19?
We see that outbreaks of infectious diseases are becoming more frequent, even when we account for the so-called “reporting bias::” surveillance of such events becoming better with time and surveillance being better funded in the North than in the South.
60% of infectious diseases are zoonotic, meaning that they are spread from animals to humans and 72% of these zoonoses originate from wildlife. COVID-19 is just the last in a long list of zoonoses originating from wildlife. Other recent outbreaks include SARS, Ebola, avian influenza and swine influenza. As human activities continue to disturb ecosystems worldwide, we are likely to see more pathogens crossing from wildlife to humans in the future. This should serve as a call to better manage our relationship with nature in general, and wildlife in particular.
Why are we seeing more cases of diseases crossing from animals to humans? Where are they coming from?
Evidence points to bushmeat trade and consumption as the likely driver for the emergence of COVID-19. The emergence of SARS and Ebola was also driven by bushmeat consumption and trade. However, when looking at past outbreaks of zoonoses caused by a pathogen with a wildlife origin, land use changes, generally due to changes in agricultural practices, has been the leading driver.
Pathogens tends to emerge in well known “disease hotspots,” which tend to be areas where high wildlife biodiversity overlaps with high population density. These hotspots also tend to be at lower latitude. Interestingly, many of these are located in regions where CIMMYT’s activities are concentrated: Central America, East Africa and South Asia. This, in addition to the fact that agricultural changes are a major driver of the emergence of zoonoses, means that CIMMYT researchers may have a role to play in preventing the next global pandemic.
How exactly does biodiversity loss and land use change cause an increase in zoonotic diseases?
There are at least three mechanisms at play. First, increased contact between wildlife and humans and their livestock because of encroachment in ecosystems. Second, selection of wildlife species most able to infect humans and/or their livestock — often rodents and bats — because they thrive in human-dominated landscapes. Third, more pathogens being carried by these surviving wildlife species in simplified ecosystems. Pathogens tend to be “diluted” in complex, undisturbed, ecosystems.
The fast increase in the population of humans and their livestock means that they are interacting more and more frequently with wildlife species and the pathogens they carry. Today, 7.8 billion humans exploit almost each and every ecosystem of the planet. Livestock have followed humans in most of these ecosystems and are now far more numerous than wild vertebrates: there are 4.7 billion cattle, pigs, sheep and goats and 23.7 billion chickens on Earth! We live on an increasingly “cultivated planet,” with new species assemblages and new opportunities for pathogens to move from one species to another.
Wildlife trade and bushmeat consumption have received a lot of attention as primary causes of the spread of these viruses. Why has there been so little discussion on the connection with biodiversity loss?
The problem of biodiversity loss as a driver of the emergence of zoonoses is a complex one: it doesn’t have a simple solution, such as banning wet markets in China. It’s difficult to communicate this issue effectively to the public. It’s easy to find support for ending bushmeat trade and consumption because it’s easy for the public to understand how these can lead to the emergence of zoonoses, and sources of bushmeat include emblematic species with public appeal, like apes and pangolins. Bushmeat trafficking and consumption also gives the public an easy way to shift the blame: this is a local, rather than global, issue and for most of us, a distant one.
There is an inconvenient truth in the biodiversity crisis: we all drive it through our consumption patterns. Think of your annual consumption of coffee, tea, chocolate, sugar, textiles, fish, etc. But the biodiversity crisis is often not perceived as a global issue, nor as a pressing one. Media coverage for the biodiversity crisis is eight times lower than for the climate crisis.
Agriculture is a major cause of land use change and biodiversity loss. What can farmers do to preserve biodiversity, without losing out on crop yields?
Farming practices that reduce the impact of agriculture on biodiversity are well known and form the foundation of sustainable intensification, for which CIMMYT has an entire program. A better question might be what we can do collectively to support them in doing so. Supportive policies, like replacing subsidies by incentives that promote sustainable intensification, and supportive markets, for example using certification and labeling, are part of the solution.
But these measures are likely to be insufficient alone, as a large share of the global food doesn’t enter the market, but is rather consumed by the small-scale family farmers who produce it.
Reducing the negative impact of food production on biodiversity is likely to require a global, concerted effort similar to the Paris Agreements for climate. As the COVID-19 pandemic is shocking the world, strong measures are likely to be taken globally to avoid the next pandemic. There is a risk that some of these measures will go too far and end up threatening rural livelihoods, especially the most vulnerable ones. For example, recommending “land sparing” — segregating human activities from nature by maximizing yield on areas as small as possible — is tempting to reduce the possibility of pathogen spillover from wildlife species to humans and livestock. But food production depends on ecosystem services supported by biodiversity, like soil fertility maintenance, pest control and pollination. These services are particularly important for small-scale family farmers who tend to use few external inputs.
How can we prevent pandemics like COVID-19 from happening again in the future?
There is little doubt that new pathogens will emerge. First and foremost, we need to be able to control emerging infectious diseases as early as possible. This requires increased investment in disease surveillance and in the health systems of the countries where the next infectious disease is most likely to emerge. In parallel, we also need to reduce the frequency of these outbreaks by conserving and restoring biodiversity globally, most crucially in disease hotspots.
Farming tends to be a major driver of biodiversity loss in these areas but is also a main source of livelihoods. The burden of reducing the impact of agriculture on biodiversity in disease hotspots cannot be left to local farmers, who tend to be poor small-scale farmers: it will have to be shared with the rest of us.
Disclaimer: The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the CGIAR Research Program on Wheat (WHEAT).
Daily life as
we know it has grinded to a halt and crop scientists are pondering next steps
in face of the global COVID-19 crisis. Hans Braun, Director of the Global Wheat
Program at the International Maize and Wheat Improvement Center (CIMMYT) and
the CGIAR Research Program on Wheat, joins us for a virtual chat to discuss the
need for increased investment in crop disease research as the world risks a
food security crisis.
What have you learned from
your work on contagious wheat diseases that we can take away during this time?
epidemics go back to biblical times. Wheat scientists now believe Egypt’s
“seven bad years” of harvest referenced in the Bible were due to a stem rust
So, we know what happens when we have a crop epidemic: diseases can completely wipe out a harvest. I have seen subsistence farmers stand in front of their swaying, golden wheat fields, but there is not a single grain inside the spikes. All because of wheat blast.
are a lot of parallel issues that I see with COVID-19.
epidemiology models for humans which we see now have a lot in common with plant
epidemiology. For example, if you take a wheat field sown with a variety which
is rust-resistant and then you get a spore which mutates and overcomes the
resistance — like COVID 19 overcomes the human immune system — it then takes
about two weeks for it to sporulate again and produce millions of these mutated
spores. They sporulate once more and then you have billions and trillions of
spores — then the wheat fields at the local, national and, in the worst case,
regional level are severely damaged and in worst case are going to die.
problem is that since we cannot quarantine wheat, if the weather is favorable
these spores will fly everywhere and — just like with COVID-19 — they don’t
need a passport to travel.
Could you elaborate on
that? How can wheat diseases go global?
Usually it takes around 5 years, sometimes less, until a mutation in a rust spore can overcome the resistance of a wheat variety. Every so often, we see rust epidemics which cover an entire region. To monitor this movement, the Borlaug Global Rust Initiative of Cornell University and CIMMYT, funded by the Bill & Melinda Gates Foundation and DFID, established a global rust monitoring system that provides live data on spore movements.
example, if you have a new race of stem rust in Yemen — and in Yemen wheat
matures early — and then farmers burn the straw, their action “pushes” the
spores up into the air, thus allowing them to enter the jet stream and cover
2,000 to 5,000 kilometers in a short period of time. Spores can also be carried
on clothes or shoes by people who walked into an infected wheat field. Take Australia,
for example, which has very strict quarantine laws. It is surrounded by sea and
still eventually they get the new rust races which fly around or come with
travelers. One just cannot prevent it.
Could climate change
exacerbate the spreading of crop diseases?
the climate and its variability have a lot to do with it. For example, in the
case of yellow rust, what’s extremely important is the time it takes from sporulation to sporulation. Take a rust
spore. It germinates, then it grows, it multiplies and then once it is ready it
will disperse and infect wheat plants. From one dispersal to the next it takes about
In the last decades, in particular for yellow rust, new races are better adapted to high temperature and are multiplying faster. In a Nature paper, we showed that 30 years ago yellow rust was not present in the Great Plains in the US. Today, it is the most important wheat disease there. So there really is something going on and changing and that’s why we are so concerned about new wheat disease races when they come up.
What could an
epidemiologist specialized in human viruses take from this?
I think human epidemiologists know very well what happens in a case like COVID-19.
Ordinary citizens now also start to understand what a pandemic is and what its
related exponential growth means.
Maybe you should ask what policymakers can learn from COVID-19 in order to prevent plant epidemics. When it comes to epidemics, what applies to humans applies to plants. If there is a new race of a given crop disease, in that moment, the plant does not have a defense mechanism, like humans in the case of COVID-19, because we haven’t developed any immunity. While in developed countries farmers can use chemicals to control plant diseases, resource-poor farmers do not have this option, due to lack to access or if the plant protective has not been registered in their country.
In addition to this, our lines of work share a sense of urgency. If “doomsday” happens, it will be too late to react. At present, with a human pandemic, people are worried about the supply chain from food processing to the supermarket. But if we have an epidemic in plants, then we do not have the supply chain from the field to the food processing industry. And if people have nothing to eat, they will go to the streets and we will see violence. We simply cannot put this aside.
What other lessons can
policymakers and other stakeholders take away from the current crisis?
world needs to learn that we cannot use economics as the basis for disease research.
We need to better foresee what could happen.
take the example of wheat blast, a devastating disease that can destroy the
wheat spike and was initially confined to South America. The disease arrived in
Bangladesh in 2016 and caused small economic damage, maybe 30,000 tons loss in
a small geographic area — a small fraction of the national production but a
disaster for the smallholder farmer, who thus would have lost her entire wheat
harvest. The disease is now controlled with chemicals. But what if chemical
resistance is developed and the disease spreads to the 10 million hectares in
the Indo Gangetic Plains of India and the south of Pakistan. Unlikely? But what
if it happens?
Agriculture accounts for 30% of the global GDP and the research money [going to agriculture] in comparison to other areas is small. Globally only 5% of R&D is invested in research for development related to agriculture. Such a discrepancy! A million U.S. dollars invested in wheat blast research goes a long way and if you don’t do it, you risk a disaster.
If there is any
flip side to the COVID-19 disaster, it is that hopefully our governments
realize that they have to play a much more serious role in many areas, in
particular public health and disease control in humans but also in plants.
A Lloyd’s report concluded that a global food crisis could be caused by governments taking isolating actions to protect their own countries in response to a breadbasket failure elsewhere. I’m concerned that as the COVID-19 crisis continues, governments will stop exports as some did during the 2008 food price crisis, and then, even if there is enough food around, the 2008 scenario might happen again and food prices will go through the roof, with disastrous impact on the lives of the poorest.
This article was originally posted on the CGIAR website.
The novel coronavirus (COVID-19) continues to spread rapidly. Since its start in China in December, the outbreak has spread to more than 100 countries, endangering the health and livelihoods of millions. To contain the pandemic, many cities and regions across the world have been shut down, putting a halt to day-to-day activities.
As Western economies struggle with difficult decisions – it is those in the global South that are most at risk. Economies that are dependent on tourism, trade and foreign investment have fewer options at their disposal.
An urgent and coordinated global response is needed – from the global to the local level to protect populations – and especially the most vulnerable. Food security is fragile under normal circumstances and must not be ignored as part of a One Health strategy.
CGIAR, as the world’s largest public research network on food systems, provides evidence to help understand and address threats to food and nutrition security from the COVID-19 pandemic, such as:
The food system has been significantly affected, and these impacts will grow if processing enterprises cannot restart production in a near future;
Production of staple food crops such as wheat, rice, and vegetables will be affected if the outbreak continues into critical planting periods;
Domestic and international trade disruptions may trigger food price panics;
Restrictions on mobility may lead to labor shortages.
CGIAR will make available its latest research and analysis on COVID-19 to support authorities and the public in making informed decisions during the current crisis. In the research and news featured below, CGIAR scientists provide evidence-based advice and recommendations on:
Introducing enabling policies for spring planting and increasing support for production entities;
Ensuring the smooth flow of trade and making full use of the international market as a vital tool to secure food supply and demand;
Ensuring smooth logistical operations of regional agricultural and food supply chains;
Monitoring food prices and strengthening market supervision;
Protecting vulnerable groups and providing employment services to migrant workers;
Regulating wild food markets to curb the source of the disease;
Measuring impact on small and medium-sized businesses;
Analyzing how much global poverty will increase because of COVID-19.
The CGIAR Research Program on Wheat and its lead center, the International Maize and Wheat Improvement Center (CIMMYT), based in Mexico, are responding to the threat of COVID-19 and taking measures to ensure our worldwide staff is as safe as possible. While we adjust to the “new normal” of social distancing, temperature checks and quarantines, we will continue to perform field and desk research as best we can, and share our progress and findings with you through our website, newsletter, and Facebook page.
times such as this, we step back and remember the vision that brings us all
here: a world free of poverty, hunger and environmental degradation. We would
not be able pursue this vision without your support.
We hope you, your colleagues and loved ones stay safe and healthy. We are all in this together and we look forward to continuing our conversation.