The Mental Health Consequences of Rat Exposure

Research suggests that residents living in urban neighborhoods characterized by poverty, aging infrastructure, and high housing density are the most prone to rat infestations but often lack the resources to address the issue. Reliant on the action of landlords or municipal agencies, residents often live in neighborhoods with rodent cohabitants. Although a significant amount of research exists on rat-transmitted diseases and the physical health consequences of rat exposure, little is known about the effects of rat exposure on residents’ mental health. In this study, researchers conduct a literature review across public health, environmental health, medical, sociology, and urban planning journals to synthesize the research on the mental health effects of rat infestations on residents living in urban neighborhoods.

After scanning more than 750 articles, and excluding research based in rural settings, written in languages other than English, or focused on other rodents, the authors found eight articles that met their inclusion criteria. Six analyzed rat infestations as one element on a spectrum of housing and neighborhood factors affecting residents’ physical and mental health, one examined the psychological effects of rat infestations in the home, and another evaluated rat exposure as a community stressor.

Key findings

• Rat exposure negatively affected residents’ mental health. Awareness of an infestation and direct exposure to rats were both cited as mental health stressors and drivers of anxiety among residents.
• A three-year longitudinal study of residents living in multifamily buildings in Waterbury, Connecticut, found that residents with rat infestations had poorer mental health than those without rat infestations, and rat exposure triggered headaches, dizziness, and stomachaches.
• A qualitative study of Baltimore residents found that residents who reported daily rat sightings and perceived rat infestations to be most problematic reported greater depressive symptoms than residents exposed to rats less frequently.
• Perceptions of rat exposure were linked with other neighborhood-level environmental stressors. Residents who perceived rat infestations as problematic also lived on blocks with other indicators of neighborhood disorder, such as vacant properties.
• In two studies, researchers found that landlords’ inaction in dealing with rodent infestations elevated tenant stress levels, and, in some cases, conflicts over rat infestations led to verbal abuse and threats of eviction.

Photo by Heiko Kiera/Shutterstock