Environmental Health II: Blood Safety Quiz

Bite of Blood Safety: Environmental Health II

• Ontario and Quebec experienced an epidemic of West Nile virus in 2002, causing public concern about possible blood-borne transmission.

• Public health officials were concerned about a recurrence of blood-borne illnesses like HIV and hepatitis C, leading to the implementation of a nucleic acid amplification test (NAT) program to screen potential blood donors.

• This case involves several policy issues, spanning evidence, framework creation, screening processes, trade-offs, cost-effectiveness, ethics (especially the precautionary principle), and intergovernmental roles/responsibilities.

Agenda

• Environmental Health (Vector-borne diseases, blood safety)
• Krever Commission (1997): Blood safety matters
• Naylor Report (2003): Emerging infectious diseases, globalization, and bioterrorism.
• Precautionary Principle: Background & practical applications.
• Risk management science, Failure mode and effects analysis (FMEA)
• Cost-effectiveness analysis
• Cost-utility analysis
• Ethical decision-making in policy

Related/Support Readings in Chapter 1

• Federal vs. Unitary models
• Federalism in Canada: The Constitution Act, 1867
• Framing
• Precautionary Principle
• Public Health
• Canada Health Act
• Economic Analysis (cost-effectiveness)
• Screening

Learning Objectives

• Understand the importance of vector-borne diseases (VBD) and blood safety.
• Summarize the key findings of the Krever Commission and Naylor Report regarding blood safety and beyond.
• Identify how framing processes influence policy instrument selection.
• Describe the origin and application of the precautionary principle in policymaking.
• Summarize the role of risk management science in public health policy.
• Differentiate between cost-effectiveness and cost-utility analysis methods.
• Define the Incremental Cost-Effectiveness Ratio (ICER).

General VBD Overview

• Vector-borne diseases (VBD) are spread through the bite of an infected arthropod (e.g., mosquito, tick).
• Examples of VBD discussed include West Nile Virus, Eastern Equine Encephalitis, Zika, and Lyme disease.

West Nile Virus

• First recognized in Africa in the 1930s.
• Circulates between birds and mosquitoes.
• Specific mosquito species (e.g., Culex pipiens and Culex restuans) act as vectors to humans.
• First detected in New York in 1999, and later spread across North America.
• First detected in Ontario, Canada in 2001, becoming a public health concern in 2003.

Mosquitoes

• West Nile Virus, Eastern Equine Encephalitis, and Zika are all mosquito-borne viruses.
• A significant portion of infections (up to 80%) are asymptomatic.
• Severe symptomatic cases can include brain inflammation, muscle weakness, paralysis, and death.

Naylor Report (2003): Emerging Infectious Diseases

• Emerging infectious diseases are those newly identified or showing increasing incidence.
• Examples mentioned include Ebola virus (1977), Legionnaires' disease (1977), and HIV/AIDS (1983).

Framing (Problem Identification)

• Nature of the condition (potential or available tests)
• Alternative policy options
• Risk to blood supply (Krever Commission)
• Zero tolerance / Precautionary Principle
• Costs of doing something vs. not doing something (ethical implications)

Understanding the Nature of the Problem

• Recognizing what we know and what we don't know about emerging issues.
• Identifying potential or available tests.
• Developing plans to rapidly address emerging problems.
• Exploring alternative policy solutions.

Precautionary Principle

• Precautionary action should be taken in the face of potential harm, regardless of the certainty of the scientific evidence.
• Principle 15 of Rio Declaration 1992, emphasizes precautionary approach in environmental protection.
• The precautionary principle is used to justify preventive action when significant risks exist, even if risks are not fully understood.

Precautionary Principle Principles

• Proportionality (Tailoring measures of protection to the risk level).
• Non-discrimination (Similar risks should be treated similarly).
• Consistency (Consistent preventive measures across similar situations).
• Examination of costs and benefits (comparing short and long-term effects).
• Review in light of new evidence (Adjusting or revising the level of protection based on new information).

Risk Management Science

• The systematic identification and evaluation of risks.
• Prioritization of risks according to probability and impact.
• Implementation of measures to minimize or control risks.
• Includes failure modes & effects analysis (FMEA).

Risk Assessment

• Site-specific information.
• Hazard identification.
• Toxicity assessment.
• Exposure assessment.

Risk Management

• Evaluation of public, economic, and social consequences.
• Development of risk mitigation strategies.

Cost-Economic Evaluation

• Cost of interventions involve monetary and non-monetary costs.
• Opportunity costs, which represent the value of the next best option forgone.

Trade-offs

• The tension between infinite desires and finite resources.
• The prioritization of certain benefits in relation to their costs.

Cost-Effectiveness Analysis

• Comparing the cost of interventions with the resulting outcomes.
• Natural units (e.g., heart attacks prevented, life years gained) are used for comparison.
• Incremental Cost-effectiveness Ratio (ICER) is a metric for comparison.

Cost-Utility Analysis

• A method for evaluating interventions' cost-effectiveness using QALYs.
• Comparison of health outcomes in terms of QALYs, also considering various values related to a life year.

Cost-Benefit Analysis

• Compares all costs and benefits in assessing intervention value.
• Considers intangible costs and benefits comprehensively.

Ethical Decision Making

• Ethical frameworks used in public health decisions
• Structural Functionalism, Precautionary Principle
• Virtue Ethics, Deontological theories, and Principilism.

This quiz covers critical aspects of environmental health related to blood safety, particularly in the context of the West Nile virus epidemic. It examines policy issues, the implications of the Krever and Naylor reports, and the precautionary principle in screening processes. Test your knowledge on risk management strategies and the ethics surrounding blood safety.