Agri-Health


Taking sheep for disease testing in Bako, Ethiopia
Taking sheep for disease testing in Bako, Ethiopia (photo credit: ILRI/Barbara Wieland).

World Zoonoses Day is marked annually on 6 July to commemorate the day in 1885 when Louis Pasteur successfully administered the first vaccine against a zoonotic disease when he treated a young boy who had been mauled by a rabid dog. The day is also an opportunity to raise awareness of the risk of zoonoses, infectious diseases that are spread between animals and people. 

Scientists estimate that 60% of known infectious diseases in people and 75% of new or emerging infectious diseases in people are transmitted from animals. Neglected zoonoses associated with livestock, such as brucellosis and cysticercosis, impose a huge health burden on poor people and reduce the value of their livestock assets.

Through its Animal and Human Health program, the International Livestock Research Institute (ILRI) carries out research with national and international partners towards improving the control of zoonotic diseases through a range of tools and approaches such as risk mapping and risk targeting, modelling of zoonotic pandemics, decision-support tools and advice on vaccination strategies. The program also generates evidence for policymakers on the cost and impact of zoonoses and the benefits of their prevention.

Some of our collaborative research on zoonoses includes work on developing optimal vaccination strategies for Rift Valley fever in East Africa, studying the epidemiology, ecology and socio-economics of disease emergence in Nairobi and developing an effective surveillance program for zoonoses in livestock in Kenya.

For an in-depth look, listed below are some of our research publications on zoonoses:

For more information on ILRI’s research on zoonoses, contact Bernard Bett, senior scientist at ILRI (b.bett@cgiar.org) or Eric Fèvre, professor of veterinary infectious diseases, Institute of Infection and Global Health, University of Liverpool on joint appointment at ILRI (eric.fevre@liverpool.ac.uk).

Researchers entering sampling data (photo credit: Zoonoses and Emerging Diseases).

In the cities of developing nations, where unregulated antibiotic use is common and livestock jostle with people amid often unsanitary conditions, scientists have found a potentially troubling vector for the dissemination of antimicrobial resistant bacteria: wildlife.

The epidemiological study published in the June 2019 issue of the journal Lancet Planetary Health shows that urban wildlife in Nairobi carry a high burden of clinically relevant antimicrobial resistant bacteria. The research team included scientists from the International Livestock Research Institute (ILRI), the University of Liverpool and the Kenya Medical Research Institute, among other research institutions.

Antimicrobial resistance is an increasingly serious threat to public health. Through misuse and overuse of antibacterial medication, more and more of the bacterial diseases that were once easily treated with antibiotics have become drug-resistant; these new strains of old germs require expensive and prolonged treatment at best and at worst can be lethal.

The study deployed teams of veterinary, medical, environmental and wildlife personnel to sample 99 households randomly chosen from Nairobi’s socio-economically diverse neighbourhoods.

The study found higher diversity of antimicrobial resistance in livestock and the environment than humans and wildlife. Rodents and birds were significantly more likely to carry resistance to multiple drugs when exposed to human and livestock waste through poor management practices, a common feature of lower-income neighbourhoods.

“This paper shows that contamination of urban environments with antimicrobial resistance is a serious issue. This is not just specific to Nairobi but findings can be extrapolated to other cities in Africa,” said Eric Fèvre, a joint appointed scientist at ILRI and professor of veterinary infectious diseases at the University of Liverpool.

“We tend to think of antimicrobial resistance in primarily medical terms, of developing new drugs and better using old ones. But we need to take an ecological approach to addressing this threat. Urban cities can address this by better urban planning, better waste disposal, better livestock husbandry practices. This can go far toward disrupting antimicrobial resistance exchange between wildlife, livestock and humans,” said Fèvre.

The lead author of the study, James Hassell, said, “Although we found no evidence to suggest that antimicrobial resistance carried by urban wildlife poses a direct threat to human health, that these animals harbour high levels of resistance to drugs used in human and animal medicine is particularly worrisome. Since wildlife are not treated with antibiotics, this is indicative of how pervasive antimicrobial resistance is in urban environments. Species that move freely across cities and further afield could disseminate resistance acquired in urban areas more widely.”

“We cannot address the rise of antimicrobial resistance without focusing on the environmental, ecological and social settings in which humans exist,” said Hassell.

Citation

Hassell, J.M., Ward, M.J., Muloi, D., Bettridge, J.M., Robinson, T.P., Kariuki, S., Ogendo, A., Kiiru, J., Imboma, T., Kang’ethe, E.K., Öghren, E.M., Williams, N.J., Begon, M., Woolhouse, M.E.J. and Fèvre, E.M. 2019. Clinically relevant antimicrobial resistance at the wildlife–livestock–human interface in Nairobi: An epidemiological study. Lancet Planetary Health 3(6): e259–e269.

CGIAR Research Program on Agriculture for Nutrition and Health 2018 annual report cover

The CGIAR Research Program on Agriculture for Nutrition and Health (A4NH) has published its 2018 annual report, highlighting program activities and research results from across A4NH’s five research flagships and five focus countries. These include:

  • research into consumer choices, motives and barriers through the lens of vegetable consumption in urban Nigeria;
  • building the evidence base with newly-published research that shows biofortified high-iron pearl millet can significantly improve nutrition and cognitive performance;
  • significant research contributions to help policymakers and consumers understand food safety issues and risks;
  • how agriculture and nutrition interventions delivered through community-based childcare centres can impact nutrient intake, dietary diversity and nutritional status;
  • improving hospital diagnostics for human brucellosis; and
  • an exploration of gender research projects being conducted under A4NH.

Farmer herds his three bulls in Nikhekhu Village, Dimapur, Nagaland, India (photo credit: ILRI/Stevie Mann).

Rapid urbanization in India has led to expansion of peri-urban fringes, where intensive, industry-style livestock rearing has led to emerging vulnerabilities at the human-animal-environment interface.

To better understand the health system and farm-level factors that influence the risk of transmission of bovine tuberculosis in animals and humans, a qualitative study was undertaken among smallholder dairy farms in peri-urban zones in three cities in India: Guwahati, Ludhiana and Bangalore. Data were collected through literature reviews, expert consultations and in-depth interviews.

The study, published in BMC Public Health (March 2019), found that farmers consulted veterinarians as a last resort after home remedies and quacks had failed. Damage control measures, especially with respect to selling or abandoning sick animals, added to the risk of disease transmission.

Although civic authorities believed in the adequacy of a functioning laboratory network, end users were aggrieved at the lack of services. Despite the presence of extension services, knowledge and awareness were limited, promoting risky behaviour.

In addition, the absence of policies on the management of bovine tuberculosis may have influenced stakeholders not to consider it to be a major animal and public health concern.

“Evidence is needed not only about the burden and risks, but also on possible options for control applied in the local Indian setting,” the authors say.

The study also recommends that the identified gaps in knowledge be addressed through collaborative research and One Health interventions involving both animal and human health sectors.

Access the article Community, system and policy level drivers of bovine tuberculosis in smallholder periurban dairy farms in India: A qualitative enquiry by A.S. Chauhan and others.

ILRI Clippings

Written by Silvia Alonso

Veterinary epidemiologist Silvia Alonso works at the International Livestock Research Institute (ILRI), where she contributes to the food safety flagship of the CGIAR Research Program for Agriculture for Nutrition and Health (A4NH), which is led by ILRI’s sister organization the International Food Policy Research Institute (IFPRI)

Alonso had some eye-popping things to say about food safety in Africa at the ‘First FAO/WHO/AU International Food Safety’ conference, held in Addis Ababa, 12–13 Feb 2019.

But first, for context, see below what The Economist Espresso had to say about this week’s food safety conference in the Ethiopian capital, where a Global Food Safety Partnership report was launched, to which ILRI scientists made many contributions (Hungry for change: Food safety (12 Feb 2019).

‘With an estimated 600m cases each year, food-borne diseases are an under-appreciated public-health problem. Africa, which suffers 137,000…

View original post 610 more words

To the grazing field, Afar, Ethiopia

Cattle going to the grazing field in Afar region, Ethiopia (photo credit: ILRI/Apollo Habtamu).

Climate change influences the occurrence and transmission of a wide range of livestock diseases through multiple pathways. Diseases caused by pathogens that spent part of their life cycle outside the host (for instance, in vectors or the environment) are more sensitive in this regard, compared to those caused by obligate pathogens.

A newly published book, The Climate-Smart Agriculture Papers, brings together some of the latest research by agricultural scientists on climate-smart agriculture in eastern and southern Africa. The 25 chapters of the book highlight ongoing efforts to better characterize climate risks, develop and disseminate climate-smart varieties and farm management practices, and integrate these technologies into well-functioning value chains.

In a chapter on climate change and livestock diseases, scientists from the International Livestock Research Institute (ILRI) use two well-studied vector-borne diseases—Rift Valley fever and tick-borne diseases—as case studies to describe direct pathways through which climate change influences infectious disease-risk in East and southern Africa.

Access the chapter, Climate change and infectious livestock diseases: The case of Rift Valley fever and tick-borne diseases by Bernard Bett, Johanna Lindahl and Delia Grace.

Johanna Lindahl, senior scientist at the International Livestock Research Institute

Johanna Lindahl, senior scientist at the International Livestock Research Institute (photo credit: ILRI/Dinesh).

We congratulate Johanna Lindahl, a senior veterinary epidemiologist at the International Livestock Research Institute (ILRI), on receiving the 2018 Swedish Institute for Global Health Transformation (SIGHT) Award and SEK 100,000 in recognition of her excellent scientific contribution to global health. The award was presented at a ceremony held in Stockholm on 25 November 2018.

The citation for her award reads: “Johanna Lindahl has, from a holistic perspective and in cooperation with researchers from low- and middle-income countries, developed our knowledge within areas of crucial relevance for the well-being and survival of mankind globally, namely human and animal interaction (One Health) as well as antibiotic resistance.”

The decision on the recipient of the SIGHT Award 2018 was taken by the board of the Royal Swedish Academy of Sciences.

Lindahl is also an associate professor at the Swedish University of Agricultural Sciences and Uppsala University.

Next Page »