Livestock can impact human health both positively and negatively. On the negative side, most human diseases originate in animals, emerging infectious diseases tend to be zoonotic, and overuse of drugs in animals can lead to antibiotic resistance in humans. However, animal source foods also provide important nutrition that helps prevent disease. A "One Health" approach is needed to manage complex interconnections between human, animal, and environmental health. Knowledge gaps remain regarding risk assessment, emerging disease management, and applying multisectoral cooperation in practice.

1. Livestock and human health: the good, the bad, the gaps Delia Grace, ILRI ILRI APM, Addis Ababa, April 2010

2. Human Health Bads & Goods Huge impact Moderate or ? impact Small impact Zoonoses EID Drug resistance An.SF & Chronic dis. Occupational hazard Nutrition Dis. resistance Psycho-social benefits Ecosystem services

3. Big Bad: Zoonoses Most diseases (60%)are zoonotic But most burden of disease is not But in poor countries 1 in 10 will die from a zoonosis Adapted from Ecker et al., BMC Microbiol. Killer infections

4. 8 diseases > 90% of burden ( Diarr, Tb, Tetanus, Schisto, Leishman, sleeping sickness, Chagas, Arbov. ) Not just human health Kill and sicken animals Add risk to production Keeping small farmers out of markets Imposing penalties on informal sector Roth et al., WHO Bull

5. Big bad: EID Newly discovered; Recently increased in incidence or prevalence; Recently expanded in geographic or climatologic range; Jumped from animals to humans

6. Big bad: EID Even more EIDs are zoonotic (75%). The worst diseases have come from animals: Smallpox, AIDS, Spanish Flu, Black Death Currently most come from wildlife. Appear to be increasing in incidence. One new disease every 7 months.

7. Moderate bad: Drug resistance Using drugs in animals causes resistance Livestock drug use in poor countries probably not so important, use by poor farmers even less 1. Human drug use far bigger cause of resistance 2. Big problem growth promoters & mass treatments > 40% livestock < 3% vet drugs -- 3.

8. The health goods Animal source foods -> better nutrition-> help fight off disease Strong relation: diarrhoea, resp infect., tb, AIDS Variable: influenza, typhus Little: malaria, plague, tetanus Ecosystem services: regulation of disease Preventing disease spillovers Offering disease control options Canaries in the mine

9. Consensus It’s big and looming larger Its complicated ‘One world, One health’ way forward

10. Randolph et al., JAS Randolph et al., JAS Animals Owned Nutritional (Growth) Status Health Status + + Probability of Zoonotic Disease Animal Production Food Crop Production Food Crop Sales Animal & Product Sales + + + + - HH Income + + (Child) Dietary Intake + Level of Care/Feeding Behaviour + Labor Allocated to Livestock + - Labor Demands on (Female) Caregiver Hired Labor - Total Labor Demands + + + Health Inputs + Food Crop Purchases ASF Purchases HH Crop Consumption HH ASF Consumption + + + - + Nutrient Interactions Chronic Disease Risk + - Land allocation to feed Traction, nutrient cycling + - + + + + + (Female) Caregiver Income + + Wage Labour by (Female) Caregiver - - + Environmental Toxin Concentration - + Cognitive Performance + + AIDS Complications - Arrows between variables indicate hypothesized causal relationships. The + or - signs indicate hypothesized direction of effects. test test

11. Controversies We’ve never had it so good versus We face unprecedented threats and impacts A warmer, wetter, sicker world versus Many other drivers more important than climate Being poor makes you sick versus Being sick makes you poor Emerging infectious disease versus Neglected tropical disease

12. Malaysia: climate and malaria 1967-1971 : MEP 1982: Vector-borne Diseases Control Program- Policy, program & strategy development 2003: National Drug Resistance Surveillance Program 1961: Pilot Malaria Eradication Project 2006: National Treatment Review Committee: ACT 1990-92 : Field trial on insecticide treated bednet (ITN) 1993: Nationwide Use of ITN 2004: Renewed studies on simian malaria 1972-1981: Anti-Malaria Program 0 50000 300000 1961 1970 1980 1990 2000 2005 Number of Cases Temperature 25 30

13. Gaps Risk assessment & communication Risk management One World, One Health into action Managing EID globally and zoonoses locally

15. Human health Bads & Goods Take homes 60% of diseases are zoonotic. One in 10 people in poor countries will die of a zoonotic disease 75% of Emerging Infectious Diseases are zoonotic. Expect a new EID every 7 months. What you worry about and what will kill you are probably not the same…

16. Thank you for your attention