Field Epidemiologists: Disease Detectives of Public Health

Asking questions, solving mysteries and telling stories are all part of a detective’s job. They also happen to be important aspects of an epidemiologist’s job.

What is epidemiology?

Epidemiology is the study of the frequency, pattern, causes and risk factors of health problems in a specific population. We use epidemiology to address health problems in neighbourhoods, schools, cities, provinces, countries, and around the world.

Epidemiologists work on a wide range of health issues. They might, for example, study groups of people who have been exposed to and affected by something in the environment, such as pesticides. Or, at the Public Health Agency of Canada (PHAC), they might track the distribution of diseases – like Ebola in West Africa, Zika in Central and Southern America, or influenza and measles outbreaks in Canada. These epidemiologists use their findings to help determine what is making people ill and to identify ways to prevent more people from getting sick.

Sometimes called “disease detectives,” epidemiologists help provide the evidence needed for other public health professionals to make informed decisions to prevent the spread of a disease or improve the population’s health. Without epidemiology, no one would know what caused outbreaks, how to limit their spread, or how to prevent them. By solving medical mysteries and understanding how diseases spread, epidemiologists are essential to programs and policies that protect the health of Canadians.

PHAC epidemiologists in the field

Imagine there is an outbreak in Canada, such as a food-borne illness caused by bacteria like Salmonella, Listeria or E. coli. If the outbreak appears to be spreading or expanding to more than one Canadian province or territory, epidemiologists at PHAC can be called upon to support a federal response and will work to identify the source of the outbreak.

PHAC epidemiologists can be deployed anywhere in Canada or around the world to help organizations respond to public health events. PHAC has been a member of the World Health Organization’s Global Outbreak Alert and Response Network for many years. Its epidemiologists are often mobilized to support international responses following natural disasters and health events, such as earthquakes, typhoons and floods and during major outbreaks of infectious diseases.

Salman Klar was an epidemiologist with PHAC when the Agency received a request for assistance with recovery and response efforts after a typhoon hit the Philippines in July 2015. Salman, along with two other epidemiologists from Canada, worked with a team of public health professionals to help minimize the risk of outbreak from infectious diseases. He also provided support in reconstruction and recovery efforts (focusing on rehabilitation of health care facilities), monitored alerts, investigated in the field, and helped respond to other ongoing public health issues. Watch this video on Salman’s role in the Philippines for more information.

Training and development – preparing for public health emergencies

PHAC epidemiologists work across a range of functions. Some are part of a group known as Public Health Officers (PHOs), which is a broad term that encompasses a variety of health professionals, such as nurses and health-related policy analysts. (For this blog post, we’ve focused on epidemiologists, but stay tuned for future posts on more PHOs.) Others are part of the Canadian Field Epidemiology Program.

Two professional programs help ensure that PHAC has expertly trained PHOs and field epidemiologists available to respond to public health events or emergencies in Canada or abroad:

Canadian Public Health Service (CPHS)

The CPHS works to improve Canada’s overall preparedness and response to public health events or emergencies by placing PHOs in public health organizations with limited resources at the federal, provincial, territorial or local level to strengthen Canada’s public health workforce, security infrastructure, knowledge and networks. Applicants must possess a Master’s degree in epidemiology, public health, or other health-related field and must have previous experience working in a public health organization or profession. For more information on how to apply, visit the CPHS webpage.

Canadian Field Epidemiology Program (CFEP)

The CFEP trains public health professionals in applied epidemiology--the specialized skills required to respond to diverse public health issues in real-life settings. The program mobilizes field epidemiologists to locations across Canada and around the world, supporting public health organizations as they respond to urgent public health events. Applicants must have a master's degree with a specialization in epidemiology, or a degree from a recognized school of medicine and hold a valid licence to practice medicine in a Canadian province or territory, or have graduated from a veterinary school accredited or approved by the Canadian Veterinary Medical Association. Visit the CFEP webpage for more information.

More information

For more information on epidemiologists and Public Health Officers, please visit the Public Health Practice section of PHAC’s website.

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