Case Synopsis

Dr. Jacob Sanders was excited to attend the Inuvik Sunrise Festival and see friends, old and new. The evening was cut short due to the snowstorm, but the next morning, Jacob was very ill. Not knowing the cause, he assumed it was the food: Muktuk (beluga blubber), beaver, caribou, bearded seal, or blue mussels. Severely dehydrated from diarrhea, he was admitted to Inuvik Regional Hospital. Insufficient lab equipment at the hospital meant the stool samples had to be sent far away to Nunavik, Quebec where the public health unit had an onsite molecular test to diagnose the problem. When the diagnosis was finally revealed, he was shocked to learn it was a disease unknown to the Inuvik region, and nearly unseen for the past decade— cryptosporidiosis.

Cryptosporidiosis is a zoonotic infectious disease transmitted by a microscopic parasite known as Cryptosporidium. This transmission occurs via oocysts that can contaminate food or water sources. Symptoms of cryptosporidiosis include diarrhea, stomach cramps, nausea, vomiting, dehydration, fever, fatigue, and weight loss. Although it is typically a tropical disease, it was first discovered in 2013 in the Canadian Arctic in Nunavik, Quebec. The recognition of widespread human cryptosporidiosis in the Canadian Arctic is a public health concern because of its possible long-term effects on the growth and development of children in Inuit communities who already face many other challenges.

Climate change has been linked to the emergence of new infectious diseases in Northern Canada. Increased precipitation from climate change will result in increased water turbidity from high water velocity. As a result, this will mix and transport more pathogens into water sources and increase the risk of water-borne infectious disease transmission. The warmer temperatures associated with climate change will also expand the range of habitats for animal hosts and allow them to migrate further north. Consequently, this will cause animal hosts to proliferate and will increase the transmission of zoonotic infections. The Centre for Food-borne, Environmental and Zoonotic Infectious Diseases at the Public Health Agency of Canada is looking to inform decision-making and adaptation strategies to mitigate infectious diseases to protect the health of Canadians, especially for those living in the Arctic Circle.

Case Objectives

1. Demonstrate knowledge about the effects of environmental factors that affect a population’s health.

2. Assess the links between the quality of the environment and population health and exposure to infectious diseases, with an emphasis on systems thinking.

3. Demonstrate knowledge about the One Health Model, which encompasses animals, humans, and the environment.

4. Learn about the public health response and the various levels of government involved in containing an infectious disease outbreak.

5. Evaluate the impact of changes in the environment on the biology, behaviour, and psychology of populations at risk.

6. Explain how globalization affects global burdens of disease.

Case Study Questions

1. Create a CASE and DPSEEA model for Cryptosporidium. Be prepared to discuss this briefly in class.
a. List the potential indirect health impacts from climate change issues (such as an increase in temperature, change in snow composition, or change in the range and activity of infective agents) on Indigenous peoples living in the Arctic.

2. Discuss the One Health Model and how this approach could be valuable in this case.

3. Create an influence diagram to show your understanding of a systems thinking approach to this problem.

4. Discuss the effects of the following issues and brainstorm coping/adaptation strategies to address them:
a. Warmer temperatures in summer and year-around
b. Increased precipitation
c. Contaminated food and water sources
d. Changing animal migration routes

5. In collaboration with Indigenous Services Canada, discuss what actions the Public Health Agency of Canada can take to limit the exposure of Indigenous communities in Northern Canada to zoonotic infectious diseases such as Cryptosporidium? Students should look at the strategic plan of the Infectious Disease Prevention and Control Branch at the agency in order to facilitate the discussion.

6. Discuss the steps that can be taken to avoid a future outbreak of cryptosporidiosis in the Canadian Arctic.


Climate change; Cryptosporidium; One Health Model; systems thinking; zoonotic infectious diseases; Arctic Region; Indigenous peoples

Additional Author Information

Sukhmeet Singh Sachal, BSc, MPH

Michel Deilgat, MD, Medical Advisor, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases

Mark Speechley, PhD, Professor



Recommended Citation

Sachal, S.S., Deilgat, M. & Speechley, M. (2019). Crypto Climate Creep: The Movement of Tropical Infectious Disease to the Arctic. In: Sibbald, S.L. & McKinley, G. [eds] Western Public Health Casebook 2019. London, ON: Public Health Casebook Publishing.