Fighting aflatoxins: CGIAR scientists Delia Grace and John McDermott describe the disease threats and options for better control

In this 6-minute film, two leading scientists combatting aflatoxins in the food chains of developing countries describe some of the risks these toxins pose and new options for their better control. Aflatoxins are a naturally occurring carcinogenic byproduct of common fungi that grow on grains and other food crops, particularly maize and groundnuts, as well as in the milk and meat of livestock that have consumed feeds contaminated with aflatoxins. These toxins threaten public health in many poor countries.

In this short film, Delia Grace and John McDermott discuss on-going research to control aflatoxins in developing countries and why this research matters so much.

Delia Grace is a veterinary epidemiologist who leads research on both ‘food safety and zoonoses’ at the International Livestock Research Institute (ILRI) and ‘agriculture-associated diseases’, a flagship project of the CGIAR Research Program on Agriculture for Nutrition and Health (A4NH). John McDermott, another veterinary epidemiologist by training, who formerly served as ILRI’s deputy director general for research and now works for the International Food Policy Research Institute (IFPRI), is director of A4NH (Agriculture for Nutrition and Health), a multi-centre program led by IFPRI.

Earlier this week (4 Nov 2013), IFPRI and its 2020 Vision initiative jointly with the CGIAR Research Program on A4NH released a series of 19 briefs on the state of efforts to combat aflatoxins. ILRI’s Grace co-edited the series with IFPRI’s Laurian Unnevehr: ‘Aflatoxins: Finding solutions for improved food safety’. Grace and Unnevehr themselves developed 2 of the 19 briefs: ‘Tackling aflatoxins: An overview of challenges and solutions’  and The role of risk assessment in guiding aflatoxin policy’. In another of the briefs, Grace zeroes in on the dangers of aflatoxins in animal-source foods: ‘Animals and aflatoxins’. Jagger Harvey and Benoit Gnonlonfin, two scientists with ILRI’s Biosciences eastern and central Africa (BecA) Hub, along with colleagues in Australia and Cornell University, wrote the last brief in the series: ‘Improving diagnostics for aflatoxin detection‘.

Aflatoxins grow naturally on many farms, infesting grains and groundnuts, particularly after drought or insect damage and are a particularly common problem in developing countries, where aflatoxins not only pose a significant public health risk but also create a barrier to trade in agricultural commodities.

‘These toxins have a range of effects on human and animal health,’ says Grace. ‘High doses are lethal to both humans and animals and chronic consumption of lower levels of aflatoxins is associated with liver cancer and immunosuppression in children.’

Researchers have known about the problem of aflatoxins in developing countries for several decades but because these countries have largely informal markets and minimal trade, people have tended to minimize or ignore the problem.

‘But this is changing’, says McDermott. ‘Recent cases of aflatoxin-related deaths in Africa widened appreciation that this problem is important; there’s been a recent increase in investment in different control methods’, he says.

The series of briefs released this week brings together the experiences of researchers both within and outside CGIAR and contributes to efforts to help smallholder farmers better manage aflatoxins on their farms. It is important to know how crohn’s disease is diagnosed and what needs to be done.

The briefs describe health risks from aflatoxins and the state of research on aflatoxins, including new methods of detection, crop breeding and food storage and handling, as well as ways to overcome the market constraints imposed by aflatoxins.

‘We’ve assembled for policy- and other decision-makers the current state of knowledge on what we need to do about aflatoxins in tropical countries,’ says McDermott.

Read more about the briefs released this week:

http://www.ifpri.org/publication/aflatoxins-finding-solutions-improved-food-safety

Read the whole publication: Aflatoxins: Finding solutions for improved food safety, edited by Laurian Unnevehr and Delia Grace

Download

Table of Contents and Introduction

1. Tackling Aflatoxins: An Overview of Challenges and Solutions
by Laurian Unnevehr and Delia Grace

2. Aflatoxicosis: Evidence from Kenya
by Abigael Obura

3. Aflatoxin Exposure and Chronic Human Diseases: Estimates of Burden of Disease
by Felicia Wu

4. Child Stunting and Aflatoxins
by Jef L Leroy

5. Animals and Aflatoxins
by Delia Grace

6. Managing Mycotoxin Risks in the Food Industry: The Global Food Security Link
by David Crean

7. Farmer Perceptions of Aflatoxins: Implications for Intervention in Kenya
by Sophie Walker and Bryn Davies

8. Market-led Aflatoxin Interventions: Smallholder Groundnut Value Chains in Malawi
by Andrew Emmott

9. Aflatoxin Management in the World Food Programme through P4P Local Procurement
by Stéphane Méaux, Eleni Pantiora and Sheryl Schneider

10. Reducing Aflatoxins in Africa’s Crops: Experiences from the Aflacontrol Project
by Clare Narrod

11. Cost-Effectiveness of Interventions to Reduce Aflatoxin Risk
by Felicia Wu

12. Trade Impacts of Aflatoxin Standards
by Devesh Roy

13. Codex Standards: A Global Tool for Aflatoxin Management
by Renata Clarke and Vittorio Fattori

14. The Role of Risk Assessment in Guiding Aflatoxin Policy
by Delia Grace and Laurian Unnevehr

15. Mobilizing Political Support: Partnership for Aflatoxin Control in Africa
by Amare Ayalew, Wezi Chunga and Winta Sintayehu

16. Biological Controls for Aflatoxin Reduction
by Ranajit Bandyopadhyay and Peter J Cotty

17. Managing Aflatoxin Contamination of Maize: Developing Host Resistance
by George Mahuku, Marilyn L Warburton, Dan Makumbi and Felix San Vicente

18. Reducing Aflatoxins in Groundnuts through Integrated Management and Biocontrol
by Farid Waliyar, Moses Osiru, Hari Kishan Sudini and Samuel Njoroge

19. Improving Diagnostics for Aflatoxin Detection
by Jagger Harvey, Benoit Gnonlonfin, Mary Fletcher, Glen Fox, Stephen Trowell, Amalia Berna, Rebecca Nelson and Ross Darnell

References

 

Adapting agriculture to improve human health–new ILRI policy brief

A sleeping sickness patient in Soroti, Uganda

A child with sleeping sickness undergoes lengthy recovery treatment at a sleeping sickness clinic in Soroti, Uganda (photo credit: ILRI).

John McDermott, a Canadian deputy director general for research at the International Livestock Research Institute (ILRI) and a veterinary epidemiologist by training, and Delia Grace, an Irish veterinary epidemiologist working in food safety and many other areas of livestock health, have written a new policy brief on agriculture-associated diseases.

This policy brief has recently been disseminated by McDermott and Grace at an international conference on the agriculture, nutrition and health interface in New Delhi and a conference on the ‘One Health’ approach to tackling human and animal health, held in Melbourne.

McDermott and Grace argue that the way we approach agriculture does not serve human interests as a whole. ‘In the past, agricultural research and development largely focused on improving the production, productivity and profitability of agricultural enterprises. The nutritional and other benefits of agriculture were not always optimized, while the negative impacts on health, well-being and the environment were often ignored. This was especially problematic for livestock systems, with especially complex negative and positive impacts on human health and well-being.’

They give as an example a side effect of agricultural intensification: disease. ‘Highly pathogenic avian influenza (HPAI) is a notorious example of a disease that was fostered by intensified agricultural production and spread through lengthened poultry value chains and the global movement of people and animals. Large-scale irrigation projects, designed to increase agriculture productivity, have created ecosystems conducive to schistosomiasis and Rift Valley fever.’

And the reason we fail to foresee the negative effects of some agricultural practices, they say, is because the responses to disease threats are often compartmentalized. ‘Instead of analysing the tradeoffs between agricultural benefits and risks, the agriculture sector focuses on productivity, while the health sector focuses on managing disease. A careful look at the epidemiology of diseases associated with agriculture, and past experience of control efforts, shows that successful management must be systems-based rather than sectorally designed.’

‘At least 61% of all human pathogens are zoonotic (transmissible between animals and people),’ they write, ‘and zoonoses make up 75% of emerging infectious diseases. A new disease emerges every four months; many are trivial, but HIV, SARS, and avian influenza illustrate the huge potential impacts. Zoonoses and zoonotic diseases recently emerged from animals are responsible for 7% of the total disease burden in least-developed countries.

‘As well as sickening and killing billions of people each year, these diseases damage economies, societies and environments. While there is no metric that captures the full cost of disease, assessments of specific disease outbreaks suggest the scale of potential impacts. . . .

‘. . . There are two broad scenarios that characterize poor countries. At one extreme are neglected areas that lack even the most basic services; in these “cold spots,” diseases persist that are controlled elsewhere, with strong links to poverty, malnutrition and powerlessness. At the other extreme are areas of rapid intensification, where new and often unexpected disease threats emerge in response to rapidly changing practices and interactions between people, animals and ecosystems. These areas are hot spots for the emergence of new diseases (of which 75% are zoonotic). They also are more vulnerable to food-borne disease, as agricultural supply chains diversify and outpace workable regulatory mechanisms.

‘. . . What cannot be measured cannot be effectively and efficiently managed. Addressing agriculture-associated disease requires assessing and prioritizing its impacts, by measuring not only the multiple burdens of disease but also the multiple costs and benefits of potential interventions—across health, agriculture and other sectors. . . .

‘But these assessment tools and results have rarely been integrated to yield a comprehensive assessment of the health, economic and environmental costs of a particular disease. . . .

‘The complexities of agriculture-associated diseases call for more integrated and comprehensive approaches to analyse and address them, as envisioned in One Health and Eco- Health perspectives . . . . These integrated approaches offer a broad framework for understanding and addressing complex disease: they bring together key elements of human, animal and ecosystem health; and they explicitly address the social, economic and political determinants of health. Both of these global approaches recognize agriculture- and ecosystem-based interventions as a key component of multi-disciplinary approaches for managing diseases. For example, food-borne disease requires management throughout the field-to-fork risk pathway. Zoonoses in particular cannot be controlled, in most cases, while disease remains in the animal reservoir. Similarly, agriculture practices that create health risks require farm-level intervention.

‘Systemic One Health and EcoHealth approaches require development and testing of methods, tools and approaches to better support management of the diseases associated with agriculture. The potential impacts justify the substantial investment required. . . .

‘As a basis for framing sound policies, information is needed on the multiple (that is, cross-sectoral) burdens of disease and the multiple costs and benefits of control, as well as the sustainability, feasibility and acceptability of control options. An example of cross-disciplinary research that effectively influenced policy is the case of smallholder dairy in Kenya. In the light of research by ILRI and partners, assessing both public health risks and poverty impacts of regulation, the health regulations requiring pasteurization of milk were reversed; the economic benefits of the change were later estimated at USD26 million per year. This positive change required new collaboration between research, government and non-governmental organizations and the private sector, as well as new ways of working . . . .

‘Many agriculture-associated diseases are characterized by complexity, uncertainty and high-potential impact. They call for both analytic thinking, to break problems into manageable components that can be tackled over time, and holistic thinking, to recognize patterns and wider implications as well as potential benefits.

‘The analytic approach is illustrated in the new decision-support tool developed to address Rift Valley fever in Kenya. In savannah areas of East Africa, climate events trigger a cascade of changes in environment and vectors, causing outbreaks of Rift Valley fever among livestock and (ultimately) humans. Improving information on step-wise events can lead to better decisions about whether, when, where and how to institute control . . . .

‘An example of holistic thinking is pattern recognition applied to disease dynamics, recognizing that emerging diseases have multiple drivers. A synoptic view of apparently unrelated health threats—the unexpected establishment of chikungunya fever in northern Italy, the sudden appearance of West Nile virus in North America, the increasing frequency of Rift Valley fever epidemics in the Arabian Peninsula, and the emergence of bluetongue virus in northern Europe—strengthens the suspicion that a warming climate is driving disease expansion generally.

‘Complex problems often benefit from a synergy of various areas of expertise and approaches. . . . Complex problems also require a longer term view, informed by the understanding that short-term solutions can have unintended effects that lead to long-term problems—as in the case of agricultural intensification fostering health threats. . . .

‘New, integrative ways of working on complex problems, such as One Health and EcoHealth, require new institutional arrangements. The agriculture, environment and health sectors are not designed to promote integrated, multi-disciplinary approaches to complex, cross-sectoral problems. But many exciting initiatives provide examples of successful institutional collaboration. . . .

‘Agriculture and health are intimately linked. Many diseases have agricultural roots—food-borne diseases, water-associated diseases, many zoonoses, most emerging infectious diseases, and occupational diseases associated with agrifood chains. These diseases create an especially heavy burden for poor countries, with far-reaching impacts. This brief views agriculture-associated disease as the dimension of public health shaped by the interaction between humans, animals and agro- ecoystems. This conceptual approach presents new opportunities for shaping agriculture to improve health outcomes, in both the short and long terms.

‘Understanding the multiple burdens of disease is a first step in its rational management. As agriculture-associated diseases occur at the interface of human health, animal health, agriculture and ecosystems, addressing them often requires systems-based thinking and multi-disciplinary approaches. These approaches, in turn, require new ways of working and institutional arrangements. Several promising initiatives demonstrate convincing benefits of new ways of working across disciplines, despite the considerable barriers to cooperation.’

Read the whole ILRI policy brief by John McDermott and Delia Grace: Agriculture-associated diseases: Adapting agriculture to improve human health, February 2011.

A new, converging, world–Hans Rosling on the good news of the world’s health and wealth

Swedish global health researcher Hans Rosling, of TedTalk ‘animated data’ fame, happens to have agriculture, health and nutrition in low-income countries as his life-long research focus.

It was thus inspired of the International Food Policy Research Institute (IFPRI) to video-tape him for their Delhi conference this week, Leveraging Agriculture for Improving Nutrition and Health, introducing his passionate presentation of animated data on the progress the world’s countries have made over the last 200 years in terms of the length of their lifespans.

Just six decades ago, in 1948, Rosling explains, today’s Asia giants were still sick and poor. The world today, he says, still has huge differences between ‘the best and worst countries’, as well as huge inequalities within countries: China’s rich Shanghai Province, he says (and shows), has a level of health and wealth on a par with Italy, while China’s rural parts are on a level similar to that of Ghana, in West Africa.

‘Despite the enormous disparities today,’ he says, ‘we have seen 200 years of remarkable progress. That huge and historical gap between the West and the rest is now closing. We have become an entirely new, converging, world.’

Rosling ends his presentation with optimism. ‘I see a clear trend into the future, with aid, trade, green technology and peace, it’s fully possible that everybody can make it to the healthy, wealthy corner.’

Who can argue with that? Watch the video below.

Seeing the beast whole: When holistic approaches ‘come out of Powerpoints’ for better health

Purvi Mehta, Capacity Strengthening Officer

Head of capacity strengthening ILRI, Purvi Mehta-Bhatt delivered a lively presentation yesterday in New Delhi explaining how capacity building is an ‘impact pathway’ linking agriculture, nutrition and health for human well being (photo credit: ILRI).

Yesterday in New Delhi, Purvi Mehta-Bhatt, head of Capacity Strengthening at the International Livestock Research Institute (ILRI), was one of three speakers to make a presentation during a side session at the international conference ‘Leveraging Agriculture for Improving Nutrition and Health’ being put on this week by the International Food Policy Research Institute (IFPRI).

Saying it was ‘great to be home, in India’, Mehta-Bhatt, who is an Indian national based at ILRI’s Nairobi headquarters, started her 12-minute talk by getting down to basics—the basics of an elephant, that is. She told a ‘small story’ of an elephant that landed in a land where nobody had seen an elephant before. Everyone looked at this new beast in different ways, each seeing only a part of the animal. Even though all were looking at the same object, each interpreted the beast very differently, according to the small part they could see of it and according to their own interpretations. ‘This is pretty much the story of the three sectors we are talking about—agriculture, nutrition and health,’ said Mehta-Bhatt.  ‘We are all in our own silos’, she said, and need to see the beast whole.

Mehta-Bhatt sees capacity strengthening work as an important ‘impact pathway in linking these three sectors together’.

‘A piecemeal approach won’t work,’ she warned.  And although ‘this is nothing new’, she said, we still have limited capacity and understanding in this area, and only a few concrete case studies to show where linking different stakeholders in a health outcome has worked. As someone recently complained to her, it’s all very well talking about bringing all stakeholders together, but when has that ever ‘come out of Powerpoints’?

‘Capacity development is not just about training programs,’ says Mehta-Bhatt; ‘it goes beyond individual capacity building; it brings in systemic cognizance and impinges on institutional architecture, and all this happens in a process of co-learning, where messages are taken both from lab to land and from land to lab.’

Among ongoing ILRI initiatives that make use of multi-national, multi-disciplinary and multi-sectoral capacity building approaches are an ILRI-implemented Participatory Epidemiology Network for Animal and Public Health (PENAPH) with seven partners; a NEPAD-sponsored Biosciences eastern and central Africa Hub facility managed by ILRI in Nairobi and hosting many students from the region; a Stone Mountain Global Capacity Development Group of 11 members that is mapping existing capacities in the field of ‘one-health’ and co-led by the University of Minnesota and ILRI; and an EcoZD project coordinated by ILRI that is taking ecosystem approaches to the better management of zoonotic emerging infectious diseases in six countries of Southeast Asia and helping to set up two regional knowledge resource centres at universities in Indonesia and Thailand.

All of these projects, she explained, have capacity strengthening as a centrepiece; all are working with, and building on, what is already existing at the local and regional levels; and all are being conducted in a process of co-learning.

Mehta-Bhatt finished by finishing her elephant story. Capacity development, and collective action for capacity development, she said, can link the three sectors—agriculture, nutrition and health—allowing them not only ‘to recognize the elephant as a whole but to ride it as well.’

Watch the presentation by Purvi Mehta-Bhatt here:

Livestock boom risks aggravating animal ‘plagues,’ poses growing threat to food security and health of world’s poor

Shepherd in Rajasthan, India

Research released at conference calls for thinking through the health impacts of agricultural intensification to control epidemics that are decimating herds and endangering humans (Picture credit: ILRI/Mann).

Increasing numbers of domestic livestock and more resource-intensive production methods are encouraging animal epidemics around the world, a problem that is particularly acute in developing countries, where livestock diseases present a growing threat to the food security of already vulnerable populations, according to new assessments reported today at the International Conference on Leveraging Agriculture for Improving Nutrition & Health in New Delhi, India.

‘Wealthy countries are effectively dealing with livestock diseases, but in Africa and Asia, the capacity of veterinary services to track and control outbreaks is lagging dangerously behind livestock intensification,’ said John McDermott, deputy director general for research at the International Livestock Research Institute (ILRI), which spearheaded the work. ‘This lack of capacity is particularly dangerous because many poor people in the world still rely on farm animals to feed their families, while rising demand for meat, milk and eggs among urban consumers in the developing world is fueling a rapid intensification of livestock production.’

The global conference (http://2020conference.ifpri.info), organized by the International Food Policy Research Institute, brings together leading agriculture, nutrition and health experts to assess ways to increase agriculture’s contribution to better nutrition and health for the world’s most vulnerable people.

The new assessments from ILRI spell out how livestock diseases present ‘double trouble’ in poor countries. First, livestock diseases imperil food security in the developing world (where some 700 million people keep farm animals and up to 40 percent of household income depends on them) by reducing the availability of a critical source of protein. Second, animal diseases also threaten human health directly when viruses such as the bird flu (H5N1), SARS and Nipah viruses ‘jump’ from their livestock hosts into human populations.

McDermott is a co-author with Delia Grace, a veterinary and food safety researcher at ILRI, of a chapter on livestock epidemics in a new book called ‘Handbook of Hazards and Disaster Risk Reduction.’ This chapter focuses on animal plagues that primarily affect livestock operations—as opposed to human populations—and that are particularly devastating in the developing world.

‘In the poorest regions of the world, livestock plagues that were better controlled in the past are regaining ground,’ they warn, with ‘lethal and devastating impacts’ on livestock and the farmers and traders that depend on them. These ‘population-decimating plagues’ include diseases that kill both people and their animals and destroy livelihoods.

Livestock-specific diseases include contagious bovine ‘lung plague’ of cattle, buffalo and yaks, peste des petits ruminants (an acute respiratory ailment of goats and sheep), swine fever (‘hog cholera’) and Newcastle disease (a highly infectious disease of domestic poultry and wild birds). The world’s livestock plagues also include avian influenza (bird flu) and other ‘zoonotic’ diseases, which, being transmissible between animals and people, directly threaten human as well as animal health.

McDermott and Grace warn that new trends, including rapid urbanization and climate change, could act as ‘wild cards,’ altering the present distribution of diseases, sometimes ‘dramatically for the worse.’ The authors say developing countries need to speed up their testing and adoption of new approaches, appropriate for their development context, to detect and then to stop or contain livestock epidemics before they become widespread.

In a separate but related policy analysis to be presented at the New Delhi conference, McDermott and Grace focus on links between agricultural intensification and the spread of zoonotic diseases. The researchers warn of a dangerous disconnect: the agricultural intensification now being pursued in the developing world, they say, is typically focused on increasing food production and profitability, while potential effects on human health remain ‘largely ignored.’

A remarkable 61 percent of all human pathogens, and 75 percent of new human pathogens, are transmitted by animals, and some of the most lethal bugs affecting humans originate in our domesticated animals. Notable examples of zoonotic diseases include avian influenza, whose spread was primarily caused by domesticated birds; and the Nipah virus infection, which causes influenza-like symptoms, often followed by inflammation of the brain and death, and which spilled over to people from pigs kept in greater densities by smallholders.

The spread and subsequent establishment of avian influenza in previously disease-free countries, such as Indonesia, was a classic example, McDermott and Grace say, of the risks posed by high-density chicken and duck operations and long poultry ‘value chains,’ as well as the rapid global movement of both people and livestock. In addition, large-scale irrigation aimed at boosting agricultural productivity, they say, has created conditions that facilitate the establishment of the Rift Valley fever virus in new regions, with occasional outbreaks killing hundreds of people along with thousands of animals.

The economic impacts of such zoonotic diseases are enormous. The World Bank estimates that if avian influenza becomes transmissible from human to human, the potential cost of a resulting pandemic could be USD3 trillion. Rich countries are better equipped than poor countries to cope with new diseases—and they are investing heavily in global surveillance and risk reduction activities—but no one is spared the threat as growing numbers of livestock and easy movement across borders increase the chances of global pandemics.

But while absolute economic losses from livestock diseases are greater in rich countries, the impact on the health and livelihoods of people is worse in poor countries. McDermott and Grace point out, for example, that zoonotic diseases and food-borne illnesses associated with livestock account for at least 16 percent of the infectious disease burden in low-income countries, compared to just 4 percent in high-income nations.

Yet despite the great threats posed by livestock diseases, McDermott and Grace see a need for a more intelligent response to outbreaks that considers the local disease context as well as the livelihoods of people. They observe that ‘while few argue that disease control is a bad thing, recent experiences remind us that, if livestock epidemics have negative impacts, so too can the actions taken to control or prevent them.’

An exclusive focus on avian influenza preparedness activities in Africa relative to other more important disease concerns, they point out, invested scarce financial resources to focus on a disease that, due to a low-density of chicken operations and scarcity of domestic ducks, is unlikely to do great damage to much of the continent. And they argue that a wholesale slaughter of pigs in Cairo instituted after an outbreak of H1N1 was ‘costly and epidemiologically pointless’ because the disease was already being spread ‘by human-to-human transmission.’

McDermott and Grace conclude that to build surveillance systems able to detect animal disease outbreaks in their earliest stages, developing countries will need to work across sectors, integrating veterinary, medical, and environmental expertise in ‘one-health’ approaches to assessing, prioritizing and managing the risks posed by livestock diseases.

More information on why animals matter to health and nutrition: https://cgspace.cgiar.org/handle/10568/3152 and https://cgspace.cgiar.org/handle/10568/3149