Zoonoses:
The Lethal Gifts of Livestock
ILRI Livestock Live Seminar
Delia Grace
International Livestock Research Institute
31 October 2012

Overview
• Human health and disease in the 21st century
• Human diseases: legacies, souvenirs or wages?
• Lethal gifts of livestock
• Mapping poverty, zoonoses & emerging livestock
systems
• From mapping to managing

Human health in the 21st century
• 7 billion people
– 1 billion hungry;
– 2 billion with hidden hunger;
– 1.5 billion overweight or obese
• 55 million die each year
– 18 million from infection
– 1.2 million from road traffic accidents
– 170,000 from fatal agricultural accidents
– 20,000 from extreme weather events

Low income countries
Three worlds
Middle income countries
High income countries
From: WHO

Where do we get our diseases?
• Most are Earned
– Degenerative diseases: heart failure, stroke, diabetes, cancer
– Allergies, asthma, autoimmune diseases
– Sexually transmitted infections such as HSV-2, gonorrhea
• Many are Souvenirs
– Around 60% of human diseases shared with animals
– 75% of emerging infectious disease zoonotic
– Two of big burden diseases jumped species from animals to people
• Few are Legacies
– Paleolithic baseline: yaws, staph, pinworms, lice, typhoid

Spillover! Jones et al., PNAS forthcoming
•Increasing human
population and density
Pathogen flow •Human behaviour
Secondary •Expansion of agriculture
Host •Intensification of livestock
(livestock) production
Spill-over
Spill-over
Habitat change
Biodiversity
Host density Vector
Sylvatic cycle
Vector density
Reservoir Secondary
Host (wildlife) Spill-over Host (human)
Type of pathogen: mutation, Sustained transmission:
heterogeneity, host specificity - peri-domestic or urban cycle
- sub-clinical, epidemic, pandemic

Spillover + Great Societal Dislocations
= Pandemic
• Neolithic – domestication 1st epidemiological
transition
• 15th c Climate change & hunger – plague
• 16th c New world – small pox, measles
• 19th c Railways & steam ships – RP, SS
• 20th c First world war – Spanish flu
• 20th c Colonialisation & ubanisation – HIV
• 21st c Third epidemiological transition?????

Cattle 7,000 bc E
Dog 15-30,000 bc ? G. Pig 5,000 bc SA
Sahara
Donkey 4,000 bc N
Sheep 8,500 bc WA Pig 7,000 bc WA
Africa
Cat 5,800 bc Fertile Hen 6,000 bc Asia Goose 1,500 bc
crescent Germany
First epidemiological transition -- domestication leads to disease
Livestock to people: Measles, mumps, diphtheria, influenza
Rodents to people via camels?: Smallpox
People to livestock: Tuberculosis, Staph. aureus and then back again to people

Which zoonoses matter, why and to
whom?
• Neglected zoonoses
• Emerging infectious diseases: 75% zoonotic
• Food-borne diseases: 30-50% zoonotic
• Other health risks in agro-ecosystems

Overview
• Human health and disease in the 21st century
• Human diseases: legacies, souvenirs or wages?
• Lethal gifts of livestock
• Mapping poverty, zoonoses & emerging
livestock systems
• From mapping to managing

Mapping poverty and zoonoses
hotspots
• To present data and expert knowledge on
poverty and zoonoses hotspots
…….to prioritise study areas in emerging
livestock systems in the developing world,
……where prevention of zoonotic disease
might bring greatest benefit to poor people.
Commissioned by DFID

Methods
• Update global maps of poor livestock keeper
• Map rapidly emerging livestock systems
• Update map of emerging infectious diseases
(Jones et al., Nature)
• Identify priority zoonoses
• Develop first global mapping of zoonoses &
poverty burden

1. PLK
• One billion PLK depend on 19 billion livestock
• 4 countries have 44% of PLK
• 75% rural, 25% urban poor depend on livestock
• Livestock contribute typically 2-33% income
• Livestock contribute typically 6-36% protein

• Poultry in South and East Asia
• > poultry in South America
• > bovines in South and East Asia
• > poultry in sub Saharan Africa
• = pigs in sub Saharan Africa
2. ELS

• West USA & west Europe hotspots
• Last decade: S America & SE Asia
3. ZEID

4. Priority zoonoses
Top Zoonoses (multiple burdens)
• Assessed 56 zoonoses from Deaths - annual
2000000
6 listings:
responsible 2.7 billion cases, 2.5 million deaths
1800000
1600000
140000
120000
• “Unlucky 13” responsible for 2.2 billion
1400000
100000
illnesses and 2.4 million deaths
1200000
1000000 80000
800000 – All 13 have a wildlife interface
60000
600000
– 9 have a major impact on livestock
40000
400000
200000 – All 13 amenable to on-farm intervention
20000
0 0
Top 13 Next 43
zoonoses

Official reporting systems
Reporting Zoonoses Scope
system
WAHID 33 Animal
TAD Info 2 Animal
Pro Med All All
GLEWS 19 All Source: HealthMap
Health All All
Map
Africa
• 253 million SLU
• 25 million lost annually
• 12-13 million from notifiable disease
• 80,000 reported == 99.8% un-reported

Systematic literature review
• Identify databases – PubMed, AJOL, CABDirect,
Google
• Develop criteria, search algorithms
• Screen abstracts, retrieve papers, extract
information
• Map data
• Embedded case-study to compare yield of
databases with grey literature & library search

Greatest burden of endemic zoonoses falls on on
billion poor livestock keepers
• Unlucky 13 zoonoses sicken 2.4 billion
people, kill 2.2 people and affect more
than 1 in 7 livestock each year

Multiple burdens of zoonoses
currently or in the last year
• 12% of animals have brucellosis, reducing production by 8%
• 10% of livestock in Africa have HAT, reducing their production by 15%
• 7% of livestock have TB, reducing their production by 6% and from 3-10%
of human TB cases may be caused by zoonotic TB
• 17% of smallholder pigs have cysticercosis, reducing their value and
creating the enormous burden of human cysticercosis
• 27% of livestock have bacterial food-borne disease, a major source of food
contamination and illness in people
• 26% of livestock have leptospirosis reducing production and acting as a
reservoir for infection
• 25% of livestock have Q fever, and are a major source of infection of
farmers and consumers

Hotspots
• PLK: S. Asia 600 m, SSA 300 m
• ELS: India, Myanmar, Bangladesh, Pakistan
• ZEID: W Europe, W USA
• Zoonoses: S. Asia > EC Africa
• BIG SIX
– S Asia: India, Bangladesh, Pakistan
– Africa: Ethiopia, Nigeria, Congo

Overview
• Human health and disease in the 21st century
• Human diseases: legacies, souvenirs or wages?
• Lethal gifts of livestock
• Mapping poverty, zoonoses & emerging livestock
systems
• From mapping to managing

From mapping to managing
Agriculture for Nutrition and Health
WHY?
• More than 2 billion people worldwide are micronutrient deficient
• 180 million children under the age of 5 are stunted
• Agriculture associated diseases sicken billions and kill millions each year
For these reasons, and many more, progress in improving the nutrition and health of poor farmers and
consumers (especially women and young children) is vital and urgent

Key development implementers
Agriculture associated (public sector, private sector, NGOs)
diseases (AAD) and enablers
(policy makers, academia, investors)
in agriculture, health and social
development
Human are able
health (have evidence, motivation, capacity)
Animal
health to reduce multiple burdens of AAD
in high-risk populations
through effective, sustainable and
equitable agricultural
(including agro-ecosystem and agro-
Agro- food chain)
Ecosystems and innovations
value chains (technological, institutional, market,
and social)
24

Initial Research Priorities
AGRICULTURE-ASSOCIATED DISEASES –
BIG 5
• Food safety
1. Risk management in informal markets
CROSS-CUTTING
2. Mycotoxins
• Zoonoses
1. Gender & equity
3. Emerging infectious diseases
2. Capacity-building
4. Neglected zoonoses and influence
3. Communication
5. Ecohealth/ One Health

CRP 4.3 Ag Associated Disease Logic
ASSUMPTIONS / COROLLARIES
1. Informal markets are most important for poor buyers and consumers
• Current food safety regulation is ineffective and unfair
• Risk and incentive based approaches have more success
2. Rapidly intensifying and urbanizing livestock systems are an important
health risk for emerging systems and the world
• Current ignorance of disease dynamics, drivers, and emergence
• Innovative surveillance and whole-chain interventions key to reducing
burden & risk
3. Neglected zoonoses impose significant, multiple burdens on the poorest
• Current sectoral approaches leads to under-estimation & poor
management
• Integrated approaches (EH/OH) and diagnostic/control innovations
needed for sustainable cost-effective control

Highlight 1. Conducting rapid, integrated assessments of food
safety, zoonoses and nutrition in five high potential CRP 3.7
Livestock and Fish Value Chains
Hidden hunger Food insecurity Poverty Disease
THE
IMPACTS Lost income Threatened market Unsafe food
access
CRP 4.3
THE CORE PROBLEM Lost opportunities for smallholders in animal-source-food CRP 3.7
markets
THE Low Limited value High wastage & Health risks in
CAUSES productivity addition spoilage food
Limited Inappropriate Lack of market Dysfunctional Inappropriate food-
access to scale & information pricing & safety management &
inputs technologies markets regulations
INPUTS & SERVICES PRODUCTION PROCESSING MARKETING CONSUMPTION
WHOLE VALUE CHAIN

Highlight 2. Mapping & measuring the hotspots of poverty, zoonoses
and emerging livestock markets – informing donor grants

Highlight 3. Integrative approaches showing how to better
understand and manage zoonoses and emerging infections
• Published special edition on assessing • Investigating irrigation, climate • Integrated human & livestock disease
& managing urban zoonoses change & disease shifts surveys: Kenya, Laos, Vietnam, China
• Starting new project on pathogen • Made first estimate of DALYs for • Slaughter house surveys: Kenya,
flows in Nairobi RVF in Kenya Uganda, Thailand, Vietnam
• Operating platform for pathogen • Developing & testing novel
• Supporting 2 EcoHealth/OH discovery & bio-repository cysticercosis diagnostic
Resource Centers in SE Asia • Discovered virus in novel host:
• Assessed barriers & bridges to implication for human heath?
uptake of EH/OH by frontline staff

Conclusions
• Here and now, the burden of NZDs is much higher than ZEIDs
– Most are very manageable
– Pareto laws apply
• EIDs plus Great Societal Dislocations can be lethal
– Are we farming on the brink of chaos?
– When diseases is a symptom, we need to tackle the cause
– Need to better synergise NZD and EID management
• Agricultural research has an important role in integrative
approaches to improve the ‘3 healths’

Bibliography
• Grace D., (forthcoming), The Lethal Gifts of Livestock, Agriculture for Development
• Jones B., Grace D., et al. (forthcoming), Do agricultural intensification and environmental change
affect the risk of zoonoses that have a wildlife-livestock interface? PNAS
• Gannon V., Grace D. and Atwill R., (2012), Zoonotic waterborne pathogens in livestock and their
excreta – interventions. In: Dufour A and Bartram J (ed), Animal Waste, Water Quality And Human
Health, World Health Organisation, Geneva, Unites States Environmental Protection Agency, USA
and IWA publishing.
• Grace D., Kang’ethe E. and Waltner-Toews D., 2012, Participatory and integrative approaches to
food safety in developing country cities, Trop Anim Health Prod, 44 (1), 1-2.
• McDermott J. and Grace D., (2012), Agriculture-Associated Diseases: Adapting Agriculture to
Improve Human Health. Fan and Pandya-Lorch (ed). Reshaping agriculture for nutrition and health,
IFPRI publications, Washington.
• Grace D. and McDermott J., (2012), Livestock epidemics and disasters. In Kelman et al., ed
Handbook of Hazards and Disaster Risk Reduction, Routledge.
• Perry BD, Grace D and Sones K. (2011), Current drivers and future directions of global livestock
disease dynamics. PNAS,. doi 10.1073/pnas.1012953108

Acknowledgements
Mapping & Spillovers: Pam Ochungo, Flo Mutua,
Mohamed Said, An Notenbaert,………. RVC, IOZ, HSPH
CRP 4. 3 Team
Food Safety: Delia, Hung, Kristina, Kohei, Fred, Joseph, Apollinaire, Saskia,
Amos, Lucy, Bryony, Ram, Karl
Mycotoxins: Pam, Elizabeth, Teresa, Daniel, Anima
EIDs: Steve, Bernard, Alan, An, Heather, George, Richard, Tabitha, John,
Betty, Vish
Zoonoses: Eric, Phil, Elizabeth, Will, Lian, Isaiah
Ecohealth/ One Health: Jeff G, Purvi, Hung, Rainer, Korapin, Fred, Lucy, Jeff
M, Solenne, Andrew
Support: Susan, Muthoni, Peter, Nancy, Rosa, Tezira, Evelyn, Tigist, Amanda,
Diana, Rose, Joyce, Katie…….

Agriculture Associated Diseases
http://aghealth.wordpress.com/