Framing the Problem of Emerging Zoonotic

Disease Risk Using a One Health Approach

Hung Nguyen-Viet, Dominic Travis, Dirk Pfeiffer, Suwit Chotinun, Jakob

Zinsstag, Delia Grace, Boripat Siriaroonrat, Bruce Wilcox

Content

Conventional risk assessment

Issues of risk assessment applied for EZDs

Adjusted risk assessment framework based

on integrative methods

Conclusion

Integrative Approach

• Integrative research approaches (One Health, Ecohealth) are believed to be more effective for tackling the complexity associated with emerging infectious diseases than a single- or multi- disciplinary approach.

• Risk-based approaches have been widely used in environmental health and epidemiology to identify critical points where hazards can be controlled and hence risks to human health reduced.

• Risk assessment: effective science-based tool for informing decision-making

Hazard vs. Risk

Hazard: A biological, chemical or physical agent or condition with the potential to cause an adverse health effect (Codex Alimentarius 1999)

Risk : likelihood of identified hazards causing harm in exposed populations in a specified time frame including the severity of the consequences.

RISK = Chance*Hazard*Exposure*Consequence

Risk

assessment

Risk

management

Decision

Risk

Communication

Risk analysis

Risk analysis: describes how risks are dealt with

within the society

• Risk communication: Communication of risks to managers, stakeholders, public

officials, and the public.

• Risk management: How to manage the problem?

• Risk assessment (RA): Is there a problem and how severe the

problem is ?

Source: Codex (1999)

“Risk” development

1924

OIE

1940s

PSA

1950s

ADI

1960s

PRA

1994

SPS

1962

CODEX

1959

HACCP

1983

NAS 1945

FAO

1948

WHO

1970s

QRA

1990s

MRA

2001

OIE-FS

2000s Bioterrorism

.

1980s

PbRA

Grace (2011)

Application of Risk Assessment

• International standard risk assessment

frameworks: OIE/IUCN, Codex Alimentarius

• Import risk assessment

• Food safety risk assessment for animal source

foods

• Ecological risk assessment

• Natural disaster risk assessment

• (finances, banking…)

Codex Alimentarius risk assessment

framework

Risk

Communication

Risk

Management Risk

Assessment

Hazard

identification

Exposure

assessment Hazard

characterization

Risk

characterization

OIE/IUCN

Import risk

assessment

Release

assessment

Exposure

assessment

Consequence

assessment

Risk

assessment

Risk

management

Risk

assessment

Hazard

identification

Risk communication

Full Process

• Question formulation • Hazard ID

– Establish criteria

• Draw a picture – Identify critical control points

• Develop a model – ID and evaluate data sources – Input data (from monitoring or surveillance efforts)

• Run model • Assess results and effects of data quality

– Sensitivity analysis and uncertainty

• Collect more data • Rerun model

Issues of current risk assessment

• Conventional risk-based approaches applied to emerging infectious diseases: limitations.

• Many possible determinants and factors operating at different spatial and temporal scales

• Uncertainties resulting from both the lack of data and unpredictability of the dynamics involved in the disease emergence process

• Lack of resources to carry out risk assessment

• Specific and complex for public and policy makers

• Disconnection with reality

Emerging Infectious Diseases Research “Blue Print”

Wilcox and Colwell (2005)

Disease Emergence Multiple Causal Factors and Mechanisms

adapted from Daszak et al – Science - 2000

How to improve the current

conventional risk assessment

approach?

Adjusted risk assessment • Assessment of ecosystem vulnerability and

resilience as a component of risk

assessment.

Hazard

identification

Exposure

assessment Hazard

characterization

Risk

characterization

Adjusted risk assessment

• Assessment of ecosystem vulnerability and

resilience as a component of risk assessment.

• Risk assessment becomes interactive:

– categorizing and ranking hazards, vulnerable,

population, and ecosystems

– prioritizing risk issue in terms of funding, politic driven-

versus reality and societal needs using participation.

• Consider hazard, risk and risk drivers from

different perspectives including social aspect and

perception

Risk

Assessment

Risk

Management

Risk

Communication

Participatory methods

Participatory Risk Analysis (for food safety risk analysis in informal marketing system)

Concept of participatory risk analysis Grace et al (2011) Revue Africaine de Santé et de Productions Animales.

Conclusions and ways forward

• Risk assessment: effective science-based tool for informing decision-making but represent limitations to EZDs

• Need more integrative aspects and participation in risk assessment involving an ecosystem perspective (vulnerability and resilience of ecosystem, social, perrception…)

Thank you!

Emerging Pandemic Threats Program

PREDICT • RESPOND • PREVENT • IDENTIFY