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Your Next Vacation: Quarantine on Grosse le

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Grosse Ile is a place defined by disease. The two-mile long island is in the St. Lawrence River off the coast of Quebec, Canada. It functioned for over one hundred years as a quarantine station for victims of major infectious diseases. It was opened in 1832 per the recommendation of the British government: quarantine and sanitize the immigrants. The cholera outbreaks in 1832 and 1848 stand out as the most grisly periods in the island’s history; up to thirty thousand immigrants died and were buried at Grosse Ile and the surrounding ocean.

Between 1832 and 1848, emigrants poured out of Ireland. A deadly combination of an agricultural pathogen, and draconian colonial policy left millions starving. Great Britain operated Ireland under a “cottage” or “cottier” system. Irish tenants rented a plot of land in exchange for agricultural labor. The most fecund plots were reserved for British grain production. The Irish were often left with land that lacked adequate topsoil and key nutrients and supported only the monoculture of potatoes. When Phytopthora infestans caused the repeated failure of the potato crop, millions of Irish were left with no food or resources. British land holdings continued to produce grains for export during the famine, but the Irish were not allowed access to this food.

There is disagreement about whether these colonial policies were deliberately oppressive, or simply in stride with prevailing laissez-faire economic mores. The British government is purported to have viewed the famine as an opportunity to implement long-desired changes within Ireland – it was not a secret that they wished the Irish would leave Great Britain. The British in part subsidized the Irish exodus from Ireland by offering places on timber ships for the destitute – but these ships were meant for lumber, not people. These ill-equipped and dank ships were often turned away from major North American cities and diverted to Canada. As a British colony, Canada could not refuse British ships. The immigrants underwent a mandatory medical inspection when entering the country. Those who did not pass the inspection were held at Grosse Ile.


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Starved people in close quarters for a long boat ride over rough seas is a pathogen’s wildest fantasy. Many arrived suffering from cholera, dysentery, and typhus. However, Grosse Ile did not provide respite from the suffering. Patients were ushered off of boats and into a crisis situation. The Medical Commission of Canada reported miserable conditions on Grosse Ile in the summer of 1847: corpses remained in beds with living patients and vermin ate the dead laying on the beach. Inexperienced staff, improvised facilities, and ignorance of disease prevented effective management of quarantined individuals.

Neither the British nor Canadian government took action to improve conditions on Grosse Ile. Canadian nationalists at the time believed that the Irish immigrants had habits that caused a predisposition to infection and sickness, and the well-documented anti-Irish sentiments in the United States were mirrored in Canada. Policies were in place that allowed disease and starvation to “naturally” decimate a disenfranchised population. Epidemics should be managed using empirically gathered evidence, not by prejudice against a group of people.

A large commemorative Celtic cross and a memorial listing the names of the dead stand on Grosse Ile. However, it’s easy to forget that Grosse Ile is the site of a mass grave when you’re participating in the nature walks and historical reenactments advertised on the Parks Canada website. Descriptions of the island’s tourism activities do not seem to reflect the somber atmosphere apropos of an island with such a morbid past. A mock medical exam and a tour of the mercury disinfection showers do not communicate the dismal conditions faced by quarantined immigrants.

In the coming decades, we will face novel disease as a result of our dramatically changing lifestyles. The only hope of aiding the victims of future epidemics in humane and effective ways is to understand the environmental milieus that leave populations uniquely susceptible to disease.

Images: Library and Archives Canada and Parks Canada

Caitlin Contag recently graduated from USC with a degree in Policy, Planning and Development. She is in her final semester of a pre-medical post-baccalaureate program at Scripps College. When she is not underwater or studying for class, she works with the gene that confers resistance to macrolides in M. tuberculosis.

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