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

Three worlds Low income countries

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

Secondary

Host

(livestock)

Secondary

Host (human)

Reservoir

Host (wildlife)

Vector

Sylvatic cycle

Sustained transmission:

- peri-domestic or urban cycle

- sub-clinical, epidemic, pandemic

Type of pathogen: mutation,

heterogeneity, host specificity

Habitat change

Biodiversity

Host density

Vector density

Jones et al., PNAS forthcoming Spillover! •Increasing human population and density •Human behaviour •Expansion of agriculture •Intensification of livestock production

Pathogen flow

Spill-over

Spill-over Spill-over

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?????

Dog 15-30,000 bc ?

Sheep 8,500 bc WA Donkey 4,000 bc N

Africa

Cattle 7,000 bc E Sahara

Pig 7,000 bc WA

Cat 5,800 bc Fertile crescent

G. Pig 5,000 bc SA

Hen 6,000 bc Asia Goose 1,500 bc 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

• 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

1. PLK

• 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

Top Zoonoses (multiple burdens) • Assessed 56 zoonoses from 6 listings:

responsible 2.7 billion cases, 2.5 million deaths

• “Unlucky 13” responsible for 2.2 billion illnesses and 2.4 million deaths

– All 13 have a wildlife interface

– 9 have a major impact on livestock

– All 13 amenable to on-farm intervention

4. Priority zoonoses

0

20000

40000

60000

80000

100000

120000

140000

Deaths - annual

0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

1800000

2000000

Top 13zoonoses

Next 43

Official reporting systems

Reporting system

Zoonoses Scope

WAHID 33 Animal

TAD Info 2 Animal

Pro Med All All

GLEWS 19 All

Health Map

All All

Africa • 253 million SLU • 25 million lost annually • 12-13 million from notifiable disease • 80,000 reported == 99.8% un-reported

Source: HealthMap

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

• Unlucky 13 zoonoses sicken 2.4 billion

people, kill 2.2 people and affect more

than 1 in 7 livestock each year

Greatest burden of endemic zoonoses falls on on billion poor livestock keepers

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

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

From mapping to managing

24

Human health

Agro- Ecosystems and

value chains

Animal health

Key development implementers (public sector, private sector, NGOs)

and enablers (policy makers, academia, investors) in agriculture, health and social development are able (have evidence, motivation, capacity)

to reduce multiple burdens of AAD in high-risk populations

through effective, sustainable and equitable agricultural (including agro-ecosystem and agro-food chain)

innovations (technological, institutional, market, and social)

Agriculture associated diseases (AAD)

Initial Research Priorities

AGRICULTURE-ASSOCIATED DISEASES –

BIG 5

• Food safety

1. Risk management in informal markets

2. Mycotoxins

• Zoonoses

3. Emerging infectious diseases

4. Neglected zoonoses

5. Ecohealth/ One Health

CROSS-CUTTING

1. Gender & equity 2. Capacity-building

3. Communication and influence

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

WHOLE VALUE CHAIN

THE CORE PROBLEM

THE CAUSES

Lost opportunities for smallholders in animal-source-food markets

Limited access to

inputs

Inappropriate scale &

technologies

Lack of market information

Dysfunctional pricing & markets

Inappropriate food-safety management &

regulations

Threatened market access

Limited value addition

Low productivity

Health risks in food

Lost income

Food insecurity Hidden hunger

INPUTS & SERVICES PRODUCTION MARKETING PROCESSING CONSUMPTION

High wastage & spoilage

Unsafe food

Poverty Disease

THE IMPACTS

CRP 4.3

CRP 3.7

Highlight 1. Conducting rapid, integrated assessments of food safety, zoonoses and nutrition in five high potential CRP 3.7

Livestock and Fish Value Chains

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 & managing urban zoonoses

• Starting new project on pathogen flows in Nairobi

• Investigating irrigation, climate change & disease shifts

• Made first estimate of DALYs for RVF in Kenya

• Developing & testing novel cysticercosis diagnostic

• Operating platform for pathogen discovery & bio-repository

• Discovered virus in novel host: implication for human heath?

• Supporting 2 EcoHealth/OH Resource Centers in SE Asia

• Assessed barriers & bridges to uptake of EH/OH by frontline staff

• Integrated human & livestock disease surveys: Kenya, Laos, Vietnam, China

• Slaughter house surveys: Kenya, Uganda, Thailand, Vietnam

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

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…….

Acknowledgements

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