Beyond Zoonosis: The Mental Health Impacts of Rat Exposure of Inner-City Residents

This work was one of the 2018 Ron de Burger Student Award winners. 

Author: Raymond Lam, University of British Columbia – Master of Science in Occupational and Environmental Hygiene

Introduction

• Rats are a common problem in cities worldwide, but impoverished, inner-city neighborhoods are disproportionately affected because factors associated with poverty promote rat infestations and rat-human contact.
• Public health has mostly focused on disease transmission associated with rat infestations, but little is known about the non-physical consequences of this environmental exposure.
• Mental health is often neglected but is receiving increasing attention in public health research and practice.

Methods

• A systematic review and narrative synthesis of the published literature was conducted to explore the effect of rat exposure on mental health among inner-city residents.
• Titles and abstracts of articles were first reviewed to determine relevance to the research question; full text of included articles were subsequently reviewed and synthesized for evidence between the exposure and outcome.

Results & Discussion

• Literature addressing this topic was sparse (eight out of seven hundred and fifty-six articles) but the results consistently suggest that rat exposure has a negative impact on mental health.
• These impacts can be direct or indirect and themselves can be exacerbated by external variables.
• Evidence of the mental health impact of other pest infestations have been mixed, suggesting pest-specific factors, such as perception, also play a role in determining the outcome.
• Given the limited literature, many areas for future research remain: how rat infestation elicits stress, if a dose-response relationship exists between rat exposure and poor mental health, if different demographics are disproportionately affected, and possible interventions for the problem.

Conclusion

• By developing a better understanding of potential rat-related health risks, both mental and physical, public health officials can better evaluate, refine, and develop their policies regarding rats.

The full review is available below.