A Climate of Inequality: Evaluating Re-emerging Malaria Risk among Vulnerable Immigrant Populations in the Greater Toronto Area

The impacts of climate change are expected to affect certain groups disproportionately, based on the degree of inequality of social and material resources as defined by the social determinants of health (SDOH) model. One of these predicted impacts includes changes in the incidence and distribution of certain infectious diseases. In southern Ontario, this may include local sporadic outbreaks of malaria. Through travel and immigration, malaria already exists in the Greater Toronto Area (GTA) as an imported disease. Although local transmission does not occur within our current context, endemic malaria was present during the 18th and 19th centuries in southern Ontario. As such, malaria as a disease and as a cultural feature has significant presence within this region's past, its present, and possibly its future. The degree to which malaria already poses a health threat within the urban setting of the GTA, and how this may be implicated within a future climate change scenario forms the basis of this paper's investigation.

Three temporal scales (past, present, and future) were explored using various disciplines to understand the scope of both imported and potential locally-transmitted malaria. The main goals were to identify who are the vulnerable groups within the GTA and why, to explore how these themes align with historical realities of malaria in this region, and to gauge potential future vulnerability based on intersections between climatic projections and transmission requirements. These topics were investigated through literature review and through interviews with several local infectious disease specialists and health policy officials.

With regard to imported malaria, many inadequacies were recognized with respect to Canada's public health system regarding underreporting, surveillance, and disease management. Vulnerable immigrant groups were identified based on their likelihood of travelling to or immigrating from malaria-endemic regions, an overall lack of connectivity with the public health system, high rates of malaria in countries of origin, and, less directly, a disproportionate burden of TB and HIV/AIDS, a high risk of poverty, experiences of racialization, and a lack of power and influence. These circumstances have both immediate and long-term effects on health and well-being, accounting for an increased risk of exposure to malaria infection abroad, as well as determining the severity of infection. Although several groups were identified, multiple-generation south Asian and African immigrants were considered to be particularly high-risk. Historical parallels drawn between past and present susceptible immigrant groups revealed similarities of social and economic disparity and the consequent poor health outcomes. Finally, an exploration of municipal, provincial, and national literature on infectious disease generally and malaria specifically revealed certain barriers to positive social change. Most prominently, a stubborn adherence to the biomedical focus of disease within policy recommendations, associated with reactive measures such as public education and surveillance, were found to undermine the saliency of the SDOH within malaria discourse. This political and economic setting, perhaps irrespective of climate change, may further deepen existing health inequalities felt by vulnerable groups, thus providing a compelling case for the application of the SDOH as an explanatory model within all considerations of health, including infectious disease.