Taking Stock: Jul 2012 round-up of news from ILRI

Remembering Jeff Haskins

Last month, we at the International Livestock Research Institute (ILRI) and within CGIAR and the wider agricultural development communities grieved over the sudden loss of American media guru Jeff Haskins, who had spent six years in Africa covering African agriculture news stories for the American PR firm Burness Communications. Haskins, who had just turned 32, died at the Kenya coast on 14 Jul 2012. See online tributes to him from the ILRI News Blog (with links to 25 major news releases and 20 major opinion pieces that ILRI produced with the help of Jeff and his Burness team over the last five years), Pictures of Jeff Haskins (ILRI Pinterest Board), Pictures by Jeff Haskins (ILRI Pinterest Board)Burness Communications Blog, Global Crop Diversity Trust, CGIARInternational Center for Tropical AgricultureLa Vie Verte and Jeff Haskins Facebook page.

Emerging Zoonotic Diseases Events 1940-2012

Before his untimely death, Jeff Haskins in early Jul orchestrated major and widespread media coverage of a groundbreaking report by ILRI revealing a heavy burden of zoonoses, or human diseases transmitted from animals, facing one billion of the world’s poor. Some 60 per cent of all human diseases originate in animal populations. The ILRI study found five countries—Bangladesh, China, Ethiopia, India and Nigeria—to be hotspots of poverty and zoonoses. The study also found that northeastern United States, Western Europe (especially the United Kingdom), Brazil and parts of Southeast Asia may be hotspots of ‘emerging zoonoses’—those that are newly infecting humans, are newly virulent, or have newly become drug resistant. The study, Mapping of Poverty and Likely Zoonoses Hotspots, examined the likely impacts of livestock intensification and climate change on the 13 zoonotic diseases currently causing the greatest harm to the world’s poor. It was developed with support from the United Kingdom’s Department for International Development (DFID).

An opinion piece by the main author of the study, ILRI veterinary epidemiologist Delia Grace, wearing her hat as a member of the Dynamic Drivers of Disease in Africa Consortium, appeared this Jul in The Guardian‘s Poverty Matters Blog.

Azage Tegegne of IPMS awarded an honorary Doctorate of Science degree

Azage Tegegne, of ILRI and the Improving Productivity and Market Success of Ethiopian Farmers (IPMS) project, was awarded an honorary doctorate of science degree by Ethiopia’s prestigious Bahir Dar University.

Bruce Scott with ILRI Addis colleagues

ILRI bid goodbye to Bruce Scott, who served ILRI as a director for 13 years, the last decade as director of ILRI’s partnerships and communications department. Bruce is moving only down the road in Nairobi, from Kabete to Westlands, where he is taking up the position of deputy director of a new initiative of Columbia University (USA): Columbia Global Centers  ⁄ Africa.

We  compiled links to ILRI inputs to the Rio+20 conference, including how to ‘turn straw into gold’ with dual-purpose crop residues and, with the International Center for Tropical Agriculture (CIAT), how livestock feed innovations can reduce poverty and livestock’s environmental ‘hoofprint’.

ILRI produced a policy brief on ‘Preventing and controlling classical swine fever in northeast India‘.

We film interviewed ILRI director general Jimmy Smith on ILRI’s evolving new livestock strategy and on ILRI’s role in providing evidence about the ‘bads’ as well as ‘goods’ of livestock production, marketing and consumption. And we interviewed ILRI scientist Joerg Jores on his research results, which, as reported in Scientific American, show that the pathogen that causes cattle pneumonia (CBPP) arose with domestication of ruminants ten thousand years ago, but only ‘heated up’ and began causing disease relatively recently.

Commissioners in Africa

An Australian contingent visited ILRI this month and launched a new initiative, the Australian International Food Security Centre, to improve food security in Africa. The centre, which falls under the Australian Centre for International Agricultural Research (ACIAR), will spend USD33.8 million over four years to support food production in Africa as well as in Asia and the Pacific region.

Visit by Korea's Rural Development Authority (RDA) to ILRI in Nairobi

We reported on the signing of a memorandum of understanding by ILRI and Korea‘s Rural Development Authority (RDA) for laboratory work in Kenya, innovative platforms in an imGoats project in India and Mozambique, and training sessions on controlling zoonoses conducted by the Vietnamese members of an ILRI-led project known by its acronym EcoZD (‘Ecosystem Approaches to the Better Management of Zoonotic Emerging Infectious Diseases in Southeast Asia’).

Curious pig in Uganda raised for sale

Azage Tegegne Livestock and irrigation value chains for Ethiopian smallholders (LIVES) project, Addis Ababa, Jun (256 views).
Danilo Pezo Smallholder pig value chain development in Uganda, Wakiso, Jun (1186 views).
Derek Baker Livestock farming in developing countries: An essential resource, World Meat Congress, Paris, Jun (874 views).
Derek Baker Interpreting trader networks as value chains: Experience with Business Development Services in smallholder dairy in Tanzania and Uganda, ILRI Nairobi, Jun (1879 views).
Peter Ballantyne Open knowledge sharing to support learning in agricultural and livestock research for development projects, Addis Ababa, Jun (1589 views).
John Lynam Applying a systems framework to research on African farming systems, CGIAR drylands workshop, Nairobi, Jun (1884 views).
Bernard Bett Spatial-temporal analysis of the risk of Rift Valley fever in Kenya, European Geosciences Union Conference, Vienna, Apr (1164 views).
Nancy Johnson The production and consumption of livestock products in developing countries: Issues facing the world’s poor, Farm Animal Integrated Research Conference, Washington DC, Mar (542 views).

Researchers strengthen their partnerships in the fight against Rift Valley fever

Typical mixed crop-livestock farming of western Kenya

A mixed crop-livestock farm in Western Kenya. Livestock researchers are working towards joint efforts of preventing and controlling Rift Valley fever in eastern Africa (photo credit: ILRI/Charlie Pye-Smith).

A new effort to align the work of partners in eastern Africa and implement more synergetic research on Rift Valley fever was the focus of a recent multi-stakeholder workshop that reviewed research strategies and approaches used by veterinarians, epidemiologists, economists and public health experts in projects across Kenya.

The meeting, which was held at the International Livestock Research Institute (ILRI) on 2 February 2012, discussed ILRI’s Rift Valley fever research program, potential collaborations with partners and options of controlling the mosquito-borne viral disease that affects cattle herds in eastern and southern Africa. Epidemics of the disease, which can also infect humans, emerge after above-average and widespread rainfall and lead to death and abortion in livestock.

Participating organizations, which are conducting research on Rift Valley fever, included Kenya’s ministries in charge of livestock development and public health, the universities of Nairobi and Egerton, Kenya Agricultural Research Institute and Kenya Medical Research Institute. Also attending the workshop were staff of the African Union Interafrican Bureau for Animal Resources (AU-IBAR), Swiss Tropical and Public Health Institute, the Nairobi office of the US Centres for Disease Control and Food and Agriculture Organization of the United Nations (FAO).

‘Our research in Rift Valley fever is benefitting from increasing collaboration,’ said Bernard Bett, an epidemiologist with ILRI. ‘These “joined up” efforts, are supporting joint assessments of the prevalence of zoonotic diseases in both animals and humans and are helping to increase the relevance of the research leading to more effective interventions.’

This strategy should lead to lower costs of doing research and implementing human and animal health interventions and a reduced burden of Rift Valley fever on the region’s livestock, people, wildlife and markets.

Esther Schelling, a epidemiologist with the Swiss Tropical and Public Health Institute, and formerly a researcher with ILRI, said: ‘Collaborative efforts in addressing the challenge of Rift Valley fever can support “one health” initiatives that seek to raise the research profile of neglected zoonotic diseases in Africa and improve the effectiveness of interventions through joint surveillance, preparedness and contingency planning to reduce the amount of time it takes to control outbreaks of these diseases.’

During the meeting, ILRI shared findings from a collaborative project known as ‘Enhancing prevention and control of Rift Valley fever in East Africa by inter-sectorial assessment of control options.’ For example, an analysis, by the project, of the public health burden of Rift Valley fever outbreaks measured in disability adjusted live years (DALYs) – the first of its kind in Kenya – shows that the 2006 and 2007 outbreak resulted in 3.4 DALYs per 1000 people and household costs of about Ksh 10,000 (USD120) for every human case reported. In 2008, ILRI estimated the disease cost the Kenyan economy USD30 million. Findings from the project also included a dynamic herd model developed for pastoral systems for simulating herd dynamics during normal and drought periods and in Rift Valley fever outbreaks. This model will be used to simulate the impacts of prevention and control options for the disease.

The Nairobi meeting discussed gaps in current research practice including the absence of climate models, sampling tools and methods to support decision support tools. Participants highlighted the need for a vector profile of the disease to enable mapping of most affected and high-risk areas and the need to understand how Rift Valley fever interacts between livestock and wildlife.

The prevention and control options discussed at the meeting will be further simulated using the herd dynamic model, which will be followed by an economic analysis using a process that was agreed on in an earlier (September 2011) workshop that discussed Rift Valley fever surveillance. A cost-benefit analysis of vaccination, vector control, surveillance, and sanitary measures is now scheduled. Results from the analysis will give much-needed evidence to support creation of policies and strategies for appropriate surveillance, prevention and control of Rift Valley fever in eastern Africa.

According to Tabitha Kimani, an agricultural economist with ILRI, ‘preliminary cost benefit analysis is already showing that it is beneficial to control Rift Valley fever through vaccination.’


Read more on Rift Valley fever research at ILRI and the region:

ILRI news archive


ILRI clippings archive





Amid soaring meat costs, officials from East Africa and Middle East seek plan to keep animal diseases from disrupting livestock trade

Orma Boran cattle crossing a river in Kenya

New approach to Rift Valley fever outbreaks aims to ensure food safety as region boosts livestock imports from Africa (photo credit: ILRI/Dolan)

With increased trade in livestock products offering a possible antidote to high food prices, livestock experts from the Middle East and 12 African countries are meeting this week (13-16 June, 2011) in Dubai to develop a strategy that eliminates the need to impose devastating bans on livestock imports from the Horn of Africa, as prevention against the spread of Rift Valley fever. The strategy should expedite the flow of livestock products while increasing safety of the overall livestock trade in the region.

Convened by the African Union’s Interafrican Bureau for Animal Resources (AU-IBAR), the International Livestock Research Institute (ILRI) and the United States Agency for International Development (USAID), the workshop will encourage officials and livestock traders to use a simple ‘Decision Support Planning Tool’ to guide and moderate their responses to Rift Valley fever outbreaks.

The ‘decision support tool’ for Rift Valley fever was developed by 30 experts and decisions-makers from across the Horn of Africa with technical assistance from researchers at ILRI, the United Nations’ Food and Agriculture Organization (FAO), and other partners. The tool will be used by chief veterinary officers and other national decision-makers. Its framework identifies the sequence of events likely to occur as the risk of a disease outbreak increases.

Rift Valley fever is a mosquito-borne virus found in eastern, western and southern Africa, Yemen and Saudi Arabia. Epidemics emerge periodically with prolonged rains. Climate and land-use changes could make outbreaks more frequent. A study done by ILRI economists Karl Rich and Francis Wanyoike indicated that the Rift Valley fever outbreak in 2007 cost Kenya at least USD32 million.

‘We must avoid unnecessary disruptions in agricultural trade between East Africa and the Middle East,’ said Ahmed El Sawalhy, director of AU-IBAR. ‘Livestock products must be safe and action concerning disease outbreaks must be in line with the actual threat.’ To this end, an animal health certification model suitable for pastoral livestock production systems and that promotes OIE standards has been developed by AU-IBAR in partnership with FAO and the Royal Veterinary College, London. The model is based on risk assessment and involves integration of both upstream animal health inspection and certification at entry points, markets and at the quarantines.

Time is also of critical importance in prevention and control of transboundary animal diseases. ‘In the last Kenyan Rift Valley fever outbreak, control measures were implemented late—not until there were definitive signs of an outbreak,’ said Jeffrey Mariner, an epidemiologist at ILRI. ‘This tool links early warning signs to control measures that can be implemented before animals or people begin falling ill. The new tool could reduce the impact of Rift Valley fever, and maybe even prevent some local outbreaks and has the potential to prevent the spread of Rift Valley fever through trade.’

‘The good news,’ says Bernard Bett, an epidemiologist at ILRI, ‘is that the impact of Rift Valley fever can be mitigated with early action during an outbreak, but veterinary officers and  decision-makers need to know what interventions to implement—and when—as the  stages of an epidemic  unfold.’

Rift Valley fever is best prevented through animal vaccination. But vaccines are expensive and few governments are willing to pay for expensive vaccines unless evidence indicates an epidemic is imminent. Regional cooperation is required to build consensus on managing the disease and to prevent trade disruptions.

Larry Meserve, USAID/EA’s regional mission director commented, ‘President Obama’s Feed the Future initiative aims to increase food security throughout Africa. To succeed, we must all help to improve the capacity of leadership in the Horn of Africa to anticipate potentially disastrous events like disease epidemics so that appropriate preventive or mitigating measures are taken before it is too late. Livestock is a vital staple crop in this part of the world, and both the private and public sectors have to do everything possible to prevent unnecessary disruptions in the trade of livestock and other commodities.’

Visit the official workshop blog site: http://rvfworkshop2011.wordpress.com

Assessing animal diseases: New paper urges use of value chain analysis and information economics to understand animal disease impacts

Mozambique, Chokwe, Lhate village

Cows standing in the compound after grazing in Chokwe, Mozambique. A new study calls for improved integration between epidemiology and economics to understand economic and poverty impacts of animal diseases (photo credit: ILRI/Mann)

A new study by researchers working with the International Livestock Research Institute (ILRI) is recommending use of ‘bottom-up’ approaches that use the strengths offered by value chain analysis and information economics in assessing the impacts of animal diseases and their interaction with socio-economic and institutional factors in developing countries.

Authors Karl Rich, from the Norwegian Institute of International Affairs (NUPI) and on joint appointment with ILRI and Brian Perry, an honorary professor of veterinary medicine at the Universities of Edinburgh and Pretoria and formerly a leader of ILRI’s research team on animal health and food safety for trade, say economists and epidemiologists need to work more closely in assessing the impact of animal diseases. They recommend use of ‘participatory disease surveillance’ approaches that feature models of disease assessment that consider the context in which animal diseases occur and how they affect markets, livelihoods and poverty reduction especially in developing countries where livestock serve diverse commercial and cultural roles which affect disease control efforts.

In a paper ‘The economic and poverty impacts of animal diseases in developing countries: New roles, new demands for economics and epidemiology’ published in the 15 September 2010, online edition of the Preventative Veterinary Medicine journal, the scientists say both value chain analysis and information economics hold particular promise and relevance towards animal disease impact assessment.

They note that ‘normative’ approaches that try to guide how agents affected by diseases should behave (for example by emphasizing elimination of disease while relegating issues of disease mitigation, equity, gender and poverty) have had limited success in reducing poverty and disease prevalence in developing countries. The scientists suggest that new models that consider the context decision makers, farmers and value chain actors face in the event of animal disease outbreaks and what they actually do (not only what they should do) will contribute to more effective pro-poor policymaking.

The paper also recommends harmonizing divergent incentives among different stakeholders in developing countries noting that, for example, integrating the views of political economy and institutions engaged in animal health research will help to focus more broadly and systematically on incentives and the behaviour of those institutions and political actors, thereby helping researchers to better understand the economic impact of diseases.

The paper reviews the livelihoods and poverty impacts of animal diseases in the developing world, with a focus on Rift Valley fever, highly pathogenic avian influenza (HPAI) and foot and mouth disease. The paper also analyses the effects of these diseases through a poverty and value chains perspective and highlights ways that lessons from these perspectives can be aligned with disease control initiatives.

Rift Valley fever outbreaks are common in eastern Africa, especially after heavy rains, which lead to rises in numbers of mosquitoes that spread this viral zoonotic disease. Rift Valley fever affects cattle, sheep, goats and camels but also infects and kills humans. A recent outbreak of the disease between 2006 and 2007 killed more than 100 people in Kenya and led to significant loss of animals and livelihoods, especially for pastoralist livestock keepers.

Rich and Perry say the response of different stakeholders to diseases is based on their unique circumstances and constraints and their incentive for compliance also depends on such contexts. Their paper stresses the importance of ‘improved integration between epidemiology of disease and its relationships with economic behaviour.’

The authors call for a holistic look at the livestock sector as a system of interacting actors, each with their own values and constraints. They say that frameworks such as those offered by value chains can help identify the impacts that animal diseases generate. The  value chain framework’s emphasis on relationships, characteristics and dynamics among actors, can help identify not only who is impacted by animal disease but also how and why they are affected and how  different actors might behave and adjust in response to disease outbreaks.

To read the complete paper and its recommendation, click here

This piece is adapted from an original story posted on the Market Opportunities Digest blog written by Tezira Lore, communications specialist for ILRI’s Markets Theme.

Tool for assessing risks to Rift Valley fever outbreaks in the Horn of Africa published

Northeastern Kenya 7

A young boy herds a flock of goats on the road to Wajir from Garissa in northeastern Kenya, an area that has experienced outbreaks of Rift Valley fever, which kills both livestock and people (photo by IRIN).

Rift Valley fever occurs in East Africa as explosive outbreaks separated by prolonged periods of 8 to 10 years when the disease disappears. The episodic nature of the disease and the rapid evolution of outbreaks create special challenges for controlling the disease. Following 2006/2007 Rift Valley fever outbreaks in East Africa, decision-makers assembled their collective experiences in the form of a risk-based decision-support tool to help guide responses in future emergencies. Because a series of natural events are indicative of an increasing risk of an outbreak of Rift Valley fever, actions should be matched to this evolving risk profile. The decision-support tool is a living document written through stakeholder input. 

At a workshop convened by the Food and Agriculture Organization of the United Nations (FAO) and the International Livestock Research Institute (ILRI) and held at ILRI's headquarters, in Nairobi, Kenya, in late March 2008, participants generated the initial material, which was then compiled and edited into the first draft of the decision-support tool.

The first draft of the decision-support tool was then exposed to critical review by close to 100 participants at the United States Centers for Disease Control's Rift Valley Fever Workshop 2008, 'Scientific pathways toward public health prevention and response,' held in Nairobi in early May 2008. A small group drawn from participants at the initial workshop reviewed the revised document at a meeting held at ILRI in September 2008 and final changes recommended by them have been incorporated into this version.

This decision-support tool has been reviewed and approved by the FAO's Emergency Center for Transboundary Animal Diseases of the Regional Animal Health Center, Nairobi. The tool was developed with stakeholders under a project managed by ILRI and funded by the FAO Emergency Coordination Office for Africa.

Read more: The American Journal of Tropical Medicine and Hygiene, Decision-support tool for prevention and control of Rift Valley fever epizootics in the Greater Horn of Africa, 2010.

Traditional knowledge key to managing outbreaks of Rift Valley fever: Study points out important role livestock keepers play in veterinary surveillance

Orma Boran cattle crossing a river in Kenya

Orma Boran cattle crossing a river in Kenya. Cattle and people both can be infected with Rift Valley fever (Photo credit: R Dolan)

Livestock researchers say the traditional knowledge of local pastoralists in East Africa needs to be included in programs to better control livestock diseases in the region.

Somali and Maasai herder early warning systems both were key in identifying the risk factors and symptoms of Rift Valley fever in an outbreak in 2006/7.

Rift Valley fever is an acute viral zoonosis spread by mosquitoes. It primarily affects domestic livestock such as cattle, camels, sheep and goats, but can also infect, and kill, people, especially those handling infected animals.

First isolated in humans in the Rift Valley region of Kenya in 1930, until the 1970s Rift Valley fever was reported mainly in southern and eastern Africa, primarily Kenya, where it was considered an animal disease, despite sporadic human cases. But after the 1970s, explosive outbreaks occurred in human populations throughout Africa, Indian Ocean states and the Arabian Peninsula. Epidemics in Egypt in 1977/8 and in Kenya in 1997/8 each killed several hundred people. Another outbreak in Kenya in 2006/7 killed more than 100 people.

In East Africa, Rift Valley fever outbreaks have coincided with heavy rainfall and local flooding, which can lead to expansion of mosquito populations. In an assessment made to review lessons from the 2006/7 outbreak in East Africa carried out by scientists from the International Livestock Research Institute (ILRI) and the Kenyan and Tanzanian departments of veterinary services, researchers found that Somali pastoralists of northeastern Kenya accurately assessed the likelihood of an outbreak based on their assessments of key risk factors, and they did so long before veterinary and public health interventions began. The study also looked at the experiences of Maasai herders of northern Tanzania, who accurately recognized symptoms such as high abortion rates as indicating the presence of the infection in their herds.

Among the environmental factors the Somali communities noticed as likely to lead to an outbreak is an increase in rainfall (usually accompanied by floods) and an increase in mosquitoes. Both preceded the 2006/7 outbreak and had been present in the last outbreak of Rift Valley fever in the region in 1997/8. The Somalis also accurately associated a ‘bloody nose’, or Sandik, in their animals with Rift Valley fever.

The role of this traditional knowledge in predicting Rift Valley fever is the subject of a paper, ‘Epidemiological assessment of the Rift Valley fever outbreak in Kenya and Tanzania in 2006 and 2007’, published in the August 2010 supplement of the American Journal of Tropical Medicine and Hygiene.

The authors say that Somali pastoralists are particularly able to predict not only the symptoms of Rift Valley fever in their animals but also the likelihood of an outbreak of the disease. Indeed, observations by local communities in risk-prone areas were often more timely and definitive than the global early warning systems in use at the time of the 2006/7 outbreak.

‘Timely outbreak response requires effective early warning and surveillance systems. This study points out the important role that livestock keepers can play in veterinary surveillance,’ the authors say.

As a result of the experiences of the 2007 outbreak, the authors recommend adopting new forecasting models and surveillance systems ‘that place more emphasis on climatic information [to] increase the lead time before events and enhance the ability of decision-makers to take timely action.’

The researchers also say that outbreaks of Rift Valley fever could be managed better if disease control workers were able to run models that combined economic with epidemiologic factors. With such models, they could better determine the benefits of implementing various disease surveillance and control methods, and the best times to implement each method selected for each circumstance.

This piece is adapted from the article New journal article: An assessment of the regional and national socio-economic impacts of the 2007 Rift Valley fever outbreak in Kenya by Tezira Lore, communications specialist for ILRI’s Markets Theme.

To read the complete report and its recommendations please visit http://www.ajtmh.org/cgi/content/abstract/83/2_Suppl/65/

A related ILRI news article addresses the full effects of the 2006/7 Rift Valley fever outbreak in East Africa, including the national and regional socioeconomic impacts of the outbreak and its effects on human and animal health.

Assessing the full costs of livestock disease: The case of the 2007 outbreak of Rift Valley fever in Kenya

Bullish market

Livestock market in Garissa, in northeastern Kenya. Closure of the cattle market and disruption of cross-border cattle trade with Somalia due to outbreaks of livestock disease can worsen food insecurity among the pastoralists and agropastoralists on both sides of the border. (Photo credit: Tze-Yun Soh)

Rift Valley fever is a mosquito-transmitted zoonotic disease that harms both human health and livestock production. It can also induce large, often overlooked, economic losses among many other stakeholders in the livestock marketing chain.

A new paper published by ILRI scientists Karl Rich and Francis Wanyoike assesses and quantifies the multi-dimensional socio-economic impacts of a 2007 outbreak of Rift Valley fever in Kenya. The study is based on a rapid assessment of livestock value chains in the northeast part of the country and a national macroeconomic analysis. As would be expected, the study results show losses among producers in food security and incomes. But the researchers also found significant losses occurred among other downstream actors in the value chain, including livestock traders, slaughterhouses, casual labourers, and butchers, as well as among those in non-agricultural sectors. To better inform policy and decision making during animal health emergencies, the authors argue that we should widen our focus to include analyses that address the multitude of economic losses resulting from an animal disease.

The authors write:

‘Rift Valley fever has had significant impacts on human and animal health alike in East Africa and the Middle East. Past outbreaks in South Africa (1951), Egypt (1977/78), Kenya (1997), and Saudi Arabia (1998–2000) resulted in the cumulative loss of thousands of human lives. The 2000 outbreak in Saudi Arabia led to the imposition of trade bans of live animals from the Horn of Africa (Ethiopia, Somalia, and Kenya) that had devastating economic impacts: one study estimated that total economic value-added in the Somali region of Ethiopia fell by US$132 million because of these trade bans, a 42% reduction compared with normal years . . . .

‘In 2007, Rift Valley fever returned to East Africa, impacting both Kenya and Tanzania. Specifically hard hit by this latest outbreak were the pastoral communities of the northeastern part of Kenya. In this region, livestock serve an important livelihood function for pastoralists, with livestock trade representing over 90% of pastoral incomes . . . . Moreover, northeastern Kenya has the highest incidence of poverty within Kenya, with poverty rates of approximately 70% in 2004 . . . .

‘An overlooked component in the socio-economic analysis of animal diseases is the multiplicity of stakeholders that are affected. Rift Valley fever does not just affect producers, but also impacts a host of other service providers within the livestock supply chain and other parts of the larger economy. Cumulatively, these downstream impacts can often dwarf the impacts of the disease at the farm level, but public policy tends to concentrate primarily on losses accruing to producers. The failure to capture these diverse impacts may have important implications on the evolution and control of disease that may accentuate its impact.

‘The 2007 Rift Valley fever outbreak in Kenya had wide-ranging impacts on the livestock sector and other segments of the economy that are often overlooked in the analysis of animal disease. These impacts included production impacts, employment losses (particularly for casual labor), and a reduction in operating capital among slaughterhouses and butchers that slowed the recovery of the livestock sector once the disease had abated. On a macroeconomic basis, we estimated that Rift Valley fever induced losses of over Ksh 2.1 billion (US$32 million) on the Kenyan economy, based on its negative impacts on agriculture and other sectors (transport, services, etc.) alike.’

Read more: An Assessment of the Regional and National Socio-Economic Impacts of the 2007 Rift Valley Fever Outbreak in Kenya, by Karl Rich and Francis Wanyoike. Rich is on joint appointment with ILRI and the Norwegian Institute of International Affairs, in Oslo. ILRI researcher Wanyoike is based in Nairobi. Their paper is published in the American Journal of Tropical Medicine and Hygiene, 83(Suppl 2), 2010, pp. 52–57.

US$4.4 million awarded for research to build a climate model able to predict outbreaks of infectious disease in Africa

Cow suffering from trypanosomosis

Scientists at the University of Liverpool, in the UK, and the International Livestock Research Institute (ILRI), in Kenya, are working with 11 other African and European partners on a US$4.4-million (UK£3 million-) project to develop climate-based models that will help predict the outbreak and spread of infectious diseases in Africa.

The researchers are working to integrate data from climate modelling and disease-forecasting systems so that the model can predict, six months in advance, the likelihood of an epidemic striking. The research, funded by the European Commission Seventh Framework, is being conducted in Ghana, Malawi and Senegal. It aims to give decision-makers the time needed to deploy intervention methods to stop large-scale spread of diseases such as Rift Valley fever and malaria, both of which are transmitted by mosquitoes.

It is thought that climate change will change global disease distributions, and although scientists know a lot about the climate triggers for some diseases, they don’t know much about how far into the future these disease events can be predicted. This new project brings together experts to investigate the links between climate and vector-borne diseases, including ‘zoonotic’ diseases, which are transmissible between animals and humans.

ILRI veterinary researcher Delia Grace says that diseases shared by people and animals are under-investigated although they are critically important for public health. ‘Fully 60% of all human diseases, and 75% of emerging diseases such as bird flu, are transmitted between animals and people,’ she said.

ILRI geneticist Steve Kemp said that the project is making use of ILRI’s advanced genomics capacities to analyse pathogens from the field and to integrate the data collected on both pathogen distribution and climatic factors. ‘From ILRI’s point of view,’ Kemp said, ‘this project is particularly exciting because it brings strong climate and weather expertise that complements systems recently built by ILRI and its partners to detect outbreaks of Rift Valley fever and to determine its spread.’

The new project also complements ILRI’s ongoing work to better control trypansomosis in West African livestock, a disease transmitted by tsetse flies. Trypanosomosis, which is related to sleeping sickness in humans, causes devastating losses of animals—along with animal milk, meat, manure, traction and other benefits—across a swath Africa as big as continental USA. Members of the new modeling project will conduct research in some of the same locations as ILRI’s West African trypanosomosis project, Kemp explained, and work with some of the same partner organizations, which should generate synergies that benefit both projects.

The risk of epidemics in tropical countries increases shortly after a season of good rainfall—when heat and humidity allow insects, such as mosquitoes, to thrive and spread diseases. Matthew Baylis, from Liverpool’s School of Veterinary Science, explained how this works with Rift Valley fever: ‘Rift Valley fever can spread amongst the human and animal population during periods of heavy rain, when floodwater mosquitoes flourish and lay their eggs. If this rainfall occurs unexpectedly during the dry season, when cattle are kept in the villages rather than out on the land, the mosquitoes can infect the animals at the drinking ponds. Humans can then contract the disease by eating infected animals. Working with partners in Africa, we can bring this information together to build a much more accurate picture of when to expect epidemics.

Andy Morse, from Liverpool’s School of Environmental Sciences, said the project combines historical and contemporary climate data with disease incidence information, including that for vector-borne diseases, as well as integrating monthly and seasonal forecasts. The resulting single, seamless, forecast system, Morse said, should allow projections of disease risk to be made beyond the conventional predictable time limit. ‘All this information will be fed into a decision-support system to be developed with decision-makers on national health issues’ in the three target countries.

The project was launched at a conference at the University of Liverpool on 19 April 2010.

For more information, contact ILRI scientist Steve Kemp. ILRI email contacts are formatted as follows: f.surname@cgiar.org: replace ‘f’ with the staff member’s first initial and replace ‘surname’ with the staff member’s surname.

The 13 research partners:
Abdus Salam International Centre for Theoretical Physics (Italy), Centre de Suivi Ecologique (Senegal), Consejo Superior de Investigaciones Cientificas (Spain), European Centre for Medium-Range Weather Forecasts (UK), Fundació Privada Institut Català de Ciències del Clima (Spain), Institut Pasteur de Dakar (Senegal), International Livestock Research Institute (Kenya), Kwame Nkrumah University of Science and Technology (Ghana), Universitaet zu Koeln (Germany), University Cheikh Anta Diop de Dakar (Senegal), University of Liverpool (UK), University of Malawi (Polytechnic & College of Medicine), University of Pretoria (South Africa)

Rift Valley fever ‘may strike again’ soon

As fears have been growing that Rift Valley fever could hit East African countries again in early 2009, a research-based 'toolkit' is helping the Kenya Government to manage the risk to human and animal lives.

Songs of PraiseThe Government of Kenya and its partners are preparing for a Rift Valley fever outbreak if the short rains of this East African region are unseasonably heavy or prolonged in high-risk areas during December 2008 and January 2009 (FEWSNET: 11 December 2008). Livestock keepers are being urged to report unusually high numbers of animal deaths or sick animals with increased rates of abortion, low milk yields, yellowing of eyes, blood-stained nasal discharges or blood in faeces.

In September 2008, EMPRES WATCH, the newsletter of the Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases, a unit of the United Nations Food and Agriculture Organization (FAO), issued a chilling warning to countries in Africa and the Arabian Peninsula that Rift Valley fever could strike again soon.

ILRI veterinary epidemiologist Christine Jost says: 'While heavy rains in northern Kenya and elsewhere generated concerns that Rift Valley fever might reappear in the rainy season (October–November 2008), there have been no outbreaks of the disease reported yet in Kenya. A reported outbreak in Saudi Arabia is being controlled.'

The last outbreak of Rift Valley fever in East Africa, in late 2006 and early 2007, killed more than 300 people in Kenya, Tanzania and Somalia and severely disrupted the local and regional livestock trade and associated livelihoods. In Kenya alone, economic losses were estimated to have exceeded US$30 million, with the country’s poorest pastoral peoples bearing the brunt of the losses.

The EMPRES warning was based on climatic models that track anomalous sea-surface temperatures in the Indian and Pacific oceans. With or without accompanying El Ñino events, these have been shown to be associated with abnormally prolonged and heavy rainfall in East Africa.

Rift Valley fever is spread initially by mosquitoes feeding on livestock; unusually heavy rainfall and subsequent widespread flooding provide ideal conditions for the generation of vast swarms of these insects. Very unusually, this year a ‘positive Indian Ocean Dipole’ has been detected for the third consecutive year. This phenomenon was associated with serious outbreaks of Rift Valley fever in East Africa in 2006/07, in Sudan in 2007 and in Madagascar in 2007/08.

Over the past 70 years or so, Rift Valley fever outbreaks in East Africa have occurred on average every 10 years; before 2006, the last outbreak had occurred in 1997/98. The apparent increase in frequency of outbreaks in the region starting in 2006 may indicate that climate change is already impacting this and other diseases associated with specific climatic conditions

What is Rift Valley fever?

Rift Valley fever is a viral disease that mostly affects cattle, sheep, goats and camels and sometimes also infects people. In arid and semi-arid part of East Africa, it is associated with abnormally heavy rainfall and flooding, which provides ideal conditions for mosquitoes to emerge and breed. Livestock bitten by mosquitoes infected with the virus that causes Rift Valley fever can themselves become infected, after which a wide range of biting insects transmit the disease further.

The females of one group of mosquitoes (Aedes) can pass the virus to their eggs, which can survive for long periods of time in the soil. When flooding occurs in an area, the eggs in the soil hatch and those carrying the virus quickly develop into adult mosquitoes already infected with virus, which then transmit the virus to livestock.

It is thought that people become infected with Rift Valley fever mostly through close contact with infected livestock: animal health workers and those involved in slaughtering and butchering infected animals are at most risk. The general public is at little risk so long as people thoroughly cook any meat they eat.

Although most human Rift Valley fever cases are mild and present as flu-like conditions, the disease can be much more severe and lead to death.

Lessons learned from the 2006/07 outbreaks
In late 2006, pastoralists in northeastern Kenya observed unusually heavy rainfall and flooding, the emergence of swarms of Aedes mosquitoes and the first cases of the livestock disease they recognized as Rift Valley fever—all before an international Rift Valley fever warning was issued. Although the pastoralists reported the situation to local authorities, the flooded roads and heavy rains, in addition to the region’s remoteness and generally poor infrastructure, made acting on the reports problematic. Many roads became impassable, for example, and much of the affected region lay outside areas with mobile phone coverage. Official action in the affected and at-risk communities was taken only with the first reports of human cases, by which time it was already too late to contain the outbreak in livestock and prevent human deaths.

  • ILRI and the Kenyan and Tanzanian veterinary departments worked together to conduct a series of studies of the 2006/07 outbreak, from which several lessons emerged.
  • A government-approved contingency plan to control outbreaks of Rift Valley fever should be in place well before a possible outbreak.
  • A system should be established to make emergency funds available at an early stage of an outbreak (before human cases occur).
  • International early warning systems should be supplemented with local systems that enable pastoralists and other people in the affected areas to report unusual weather and mosquito occurrences and suspected cases of Rift Valley fever in both animals and people. The widespread availability of mobile phones and increasing mobile phone coverage now make such an approach more feasible than in the past.
  • Existing vaccines for livestock are difficult to use effectively in East Africa because:

    • the disease occurs in remote areas with poor infrastructure
    • neither manufacturers nor veterinary authorities routinely maintain large stocks of vaccine for Rift Valley fever
    • vaccine manufacturers need several months’ warning to produce sufficient new batches of the vaccine to enable sufficient populations of at-risk animals to be vaccinated
    • the existing vaccine is not ideal; it causes abortion in pregnant animals
    • vaccinating animals after cases of Rift Valley fever have been detected in a herd risks spreading the virus further via the needle used for the vaccinations
    • the long intervals between outbreaks of Rift Valley fever make routine vaccination of large numbers of livestock against the disease appear prohibitively expensive.
  • Effective communication is vital to managing outbreaks of Rift Valley fever; all those in close contact with livestock, for example, should be informed of the risks associated with slaughtering livestock and handling carcasses. Clear, authoritative messaging is perhaps the single most important action that can be taken to prevent loss of human as well as animal life.
  • Because the disease is transmitted between livestock and people, it is essential that medical and veterinary authorities collaborate closely with each other to prevent and control outbreaks.

A decision-support tool is used for contingency planning
Once an outbreak of Rift Valley fever occurs, the disease spreads rapidly, leaving little time for authorities and affected communities to weigh options and make decisions. And due to the on-average decade-long interval between outbreaks, many of those with firsthand experience of an outbreak are no longer in their posts to tackle the next.

To address this, FAO and ILRI worked with multiple stakeholders to improve control of Rift Valley fever by developing a ‘decision-support’ tool. Targeted at directors of veterinary services in the East Africa region, the tool divides an outbreak of Rift Valley fever into a sequence of 12 key events, including the normal inter-epidemic period. For each event or period, the tool recommends a set of actions to facilitate timely, evidence-based decision-making.  The tool helps decision-makers act early for prevention and control, based on an increasing levels of outbreak risk, rather than waiting for an outbreak to occur before action is taken.

Recently, in response to the Rift Valley fever warning issued by FAO, the decision-support tool was used by the Kenyan Veterinary Department to inform the drafting of a Rift Valley fever contingency plan. 

New outbreak of fatal Rift Valley fever in the Horn of Africa

Rift Valley fever is a viral disease of people and ruminant animals transmitted by mosquitoes. Epidemics frequently present as extensive abortion storms in small ruminants and cattle combined with heavy mortality in young animals. In people, the disease is most often a febrile illness without serious consequences. In a low percentage of human cases (about 1% or less), hemorrhagic complications can arise. Blindness also occasionally results. 118 deaths have been confirmed since the outbreak in November 2006 in the North-eastern province and coastal region of Kenya.

The disease is transmitted by the bite of infected mosquitoes or heavy exposure to aerosols in situations such as the slaughtering of infected animals. Outbreaks of the disease are associated with changes in local water resource management or periods of heavy rainfall. Examples have been the construction of new dams or El Nino rain events such as the one in East Africa in 1997-98 when there was a major outbreak of Rift Valley fever in Kenya and Somalia. The virus has been shown to over-winter in infected mosquito eggs. At the onset of the rains, infected mosquitoes transmit the disease to suitable amplifying hosts such as small ruminants. If vector densities are sufficiently high due to favourable environmental conditions, this starts a cascade-like recrudescence of the virus in the host and vector populations, leading to an epidemic.

Severe human cases, although an infrequent outcome of infection, are often the event that triggers recognition that an epidemic is under way.  There is need to develop early warning systems and to validate prevention and control strategies that can mitigate the evolution of outbreaks. Rift Valley fever causes serious economic losses in livestock particularly in cattle and sheep, although goats, camels, Asian water buffalo and wild antelopes may be vulnerable.

Key research questions

A number of important research questions related to Rift Valley fever and its impact remain unanswered and worthy of further research.  These include the following:

•  What is the economic impact of an RVF outbreak, particularly in terms of distribution, livelihoods, international trade, public health, and other macro-level factors?  How does the disease affect unrelated sectors (e.g., tourism)?
•  How has the disease broadly affected trade patterns in livestock products from the horn of Africa and what are potential future impacts? How can these be mitigated?
•  How effective are current vaccines in their ability to prevent disease and how frequent are side effects? There are two types of vaccines currently in use, both of which have serious disadvantages.  For human use, a ‘killed vaccine’consists of formalin-inactivated virus for restricted use.   It requires several doses and annual revaccination.  It is not approved for general distribution and is used only for laboratory workers and other specialized groups.  A live, attenuated vaccine is approved for use in livestock.  It induces a solid, life-long immunity but may cause abortions if administered to pregnant animals. 
•  What is the epidemiological impact and cost-effectiveness of alternative types of vaccination and movement control strategies?  How can these tools be best used in the face of outbreaks like the one we are experiencing now?
•  Can diagnostic tests for the disease be improved to make them more ‘user-friendly’ for field workers and remote laboratories?  Is it possible to develop good diagnostic tests to distinguish between active and past infections, and to distinguish previously exposed animals from vaccinated animals?
•  How can we enhance decision-making and promote the application of risk-based standards to ensure safe international trade of livestock products and scientifically sound trade restrictions?

 The Nairobi-based International Livestock Research Institute (ILRI) is actively seeking to become engaged in two areas.

In diagnostics, ILRI recently held discussions with the Kenya’s Department of Veterinary Services and South Africa’s Onderstepoort Veterinary Institute (OVI).  OVI have developed a field-based test to diagnose RVF infection in cattle.  This test requires only the application of a small blood sample to the device with a result obtained in about three minutes.  Such a test has advantages over a laboratory-based test, in terms of speed of diagnosis and no need for electricity or other equipment.  Although the test has profed successful in the laboratory, it has yet to undergo extensive testing in the field to ensure that it is sufficiently accurate.  It is envisaged that ILRI will be involved in this testing, using samples from the current outbreak.

On another front, ILRI is pursuing the possibility of working with a Walter Reed Project (WRP) and the US-based Centers for Disease Control (CDC) to support their ongoing efforts to understand and control this present outbreak of Rift Valley Fever.  Internal discussions within ILRI highlight three key areas in which ILRI could contribute in this process:

• Sensitise key stakeholders, particularly in government of the epidemiological and economic magnitude and impact of the current outbreak in Kenya.
• Initiate a process to identify appropriate veterinary control strategies to reduce both animal   and human incidence of the disease
• Take advantage of the current situation to collect key epidemiological and economic data to guide further research and improve risk mitigation tools

ILRI is in discussions with the WRP-CDC teams to define roles specific for ILRI in the areas of assessing the socio-economic impacts of the disease, participatory epidemiology and surveillance, and the interface between livestock and public health.  ILRI aims to help WRP-CDC in their short-run emergency response efforts as well as to use this current outbreak to help design decision-support tools to better manage future occurrences of Rift Valley Fever.