The Public Health Agency of Canada (PHAC) exists because of a pandemic. SARS hit Canada in 2003, exposed gaps in public health capacity and coordination, and prompted creation of a federal agency focused specifically on protecting and promoting population health. Two decades later, COVID-19 tested PHAC more severely than SARS ever did—and raised questions about whether the lessons of SARS had been adequately learned or sustainably implemented.
Origins and Mission
Before PHAC, federal public health functions were scattered across Health Canada, lacking dedicated leadership and organizational focus. SARS revealed the consequences: inadequate surveillance, slow response, coordination failures between federal and provincial authorities. The Naylor Report recommended a dedicated public health agency, and PHAC was established in 2004.
PHAC's mission encompasses disease surveillance and outbreak response, health promotion and disease prevention, emergency preparedness, and public health infrastructure development. It provides national leadership on public health while respecting provincial jurisdiction over healthcare delivery. The Chief Public Health Officer—Canada's top public health doctor—leads the agency and serves as the federal government's principal public health spokesperson.
The agency doesn't deliver healthcare to individual Canadians (except for specific functions like quarantine). Rather, it supports and coordinates public health systems across the country, provides expertise and data, and leads response when threats exceed provincial capacity or cross provincial boundaries.
Disease Surveillance
Monitoring disease patterns across Canada enables early detection of outbreaks and understanding of health trends. PHAC operates surveillance systems for infectious diseases, chronic diseases, injuries, and other health conditions. These systems collect data from provincial and territorial partners, analyze patterns, and report findings that inform public health action.
International surveillance connections link Canadian monitoring to global health intelligence. PHAC participates in World Health Organization networks and bilateral arrangements with other countries' health agencies. Detecting threats anywhere in the world helps Canada prepare for diseases that might arrive. Global health security depends on shared surveillance capacity.
COVID-19 exposed surveillance limitations. Data systems that worked adequately for routine surveillance struggled with pandemic-scale demands. Real-time information on case counts, hospitalizations, and outcomes proved difficult to compile across different provincial systems. The experience prompted investments in surveillance modernization—whether those investments will be sustained remains to be seen.
Emergency Preparedness and Response
PHAC maintains the National Emergency Strategic Stockpile, develops pandemic plans, and coordinates health emergency response. These functions were central to the agency's creation following SARS. Yet when COVID-19 arrived, stockpiles were inadequate, plans proved largely theoretical, and coordination mechanisms were tested beyond their limits.
The gap between planning and operational capacity became painfully apparent. Pandemic plans existed but hadn't been adequately exercised. Stockpiled materials had deteriorated without replenishment. Surge capacity that plans assumed wasn't actually available. The agency that was created to ensure pandemic readiness was not ready for the pandemic that arrived.
Post-COVID assessments have prompted reforms: investments in stockpiles and domestic manufacturing, improvements to data systems, enhanced coordination frameworks. The question is whether these improvements will be maintained through years of normalcy or erode as happened after SARS. Institutional mechanisms for sustained preparedness remain works in progress.
Health Promotion and Prevention
Beyond infectious disease, PHAC addresses chronic disease prevention, injury reduction, mental health promotion, and healthy development across the lifespan. Programs targeting physical activity, healthy eating, tobacco reduction, and other health behaviors aim to prevent illness before it occurs. Early childhood development, healthy aging, and family health receive attention.
Health promotion operates differently than disease response. Rather than reacting to specific threats, it seeks to create conditions for better health outcomes across the population. Success is measured in diseases that don't occur, disabilities prevented, and quality of life maintained. These prevention investments compete for attention and resources against more visible treatment needs.
Social determinants of health—income, education, housing, employment—shape health outcomes more than healthcare does. PHAC addresses health determinants through cross-sectoral work, but its capacity to affect determinants controlled by other government departments and other levels of government is limited. Population health improvement requires whole-of-government approaches that PHAC can advocate but cannot direct.
Relationships with Provinces and Territories
PHAC coordinates with provincial and territorial public health authorities without authority over them. The Special Advisory Committee on COVID-19 brought chief medical officers together during the pandemic, but recommendations were advisory rather than binding. Provinces made their own decisions, sometimes aligning with federal advice and sometimes diverging.
This arrangement reflects Canadian federalism: health is provincial jurisdiction, and PHAC cannot override provincial public health decisions. Coordination depends on relationship-building, shared data, and persuasion rather than command. When coordination works, it produces aligned approaches; when it fails, it produces the patchwork of provincial responses that characterized parts of the COVID response.
Strengthening coordination while respecting jurisdiction remains a governance challenge. Pre-negotiated agreements, mutual aid frameworks, and binding commitments for specific emergency circumstances might enhance coordination without fundamentally altering federal-provincial balance. But such arrangements require provincial agreement that isn't always forthcoming.
The Chief Public Health Officer
The Chief Public Health Officer (CPHO) serves as Canada's lead public health authority and PHAC head. During COVID-19, Dr. Theresa Tam became one of Canada's most visible public figures, providing regular updates and guidance. The role combines scientific expertise with public communication—an unusual combination that requires both technical credibility and media effectiveness.
The CPHO provides advice to the government and information to the public, but doesn't make policy decisions. Ministers and elected officials make policy; the CPHO informs those decisions with public health expertise. This advisory role means the CPHO can be overruled by politicians—and during COVID-19, political decisions sometimes diverged from public health recommendations.
Independence of the CPHO is debated. Some argue the role should have more authority, able to direct public health action without ministerial interference. Others argue that accountability to elected officials is appropriate—that public health decisions with major social and economic implications should be made by accountable politicians, not unelected experts.
Questions for Consideration
Has Canada adequately learned from COVID-19 to improve PHAC's capacity and preparedness? Should the Chief Public Health Officer have more authority, or is the advisory role appropriate? How should PHAC's relationship with provincial public health authorities be structured? What investments in health promotion and prevention should be priorities? How can pandemic preparedness be maintained through years without emergencies?