Frequent and intense human-bat interactions occur in buildings of rural Kenya

Simultaneous use of domestic spaces by humans and wildlife is little understood, despite global ubiquity, and can create an interface for human exposure to wildlife pathogens. Bats are a pervasive synanthropic taxon and are associated with several pathogens that can spill over and cause disease in humans. Urbanization has destroyed much natural bat habitat and, in response, many species increasingly use buildings as roosts. The purpose of this study was to characterize human interactions with bats in shared buildings to assess potential for human exposure to and spillover of bat-borne pathogens. We surveyed 102 people living and working in buildings used as bat roosts in Taita-Taveta county, Kenya between 2021 and 2023. We characterized and quantified the duration, intensity, and frequency of human-bat interactions occurring in this common domestic setting. Survey respondents reported living with bats in buildings year-round, with cohabitation occurring consistently for at least 10 years in 38% of cases. Human contact with bats occurred primarily through direct and indirect routes, including exposure to excrement (90% of respondents), and direct touching of bats (39% of respondents). Indirect contacts most often occurred daily, and direct contacts most often occurred yearly. Domestic animal consumption of bats was also reported (16% of respondents). We demonstrate that shared building use by bats and humans in rural Kenya leads to prolonged, frequent, and sometimes intense interactions between bats and humans, consistent with interfaces that can facilitate exposure to bat pathogens and subsequent spillover. Identifying and understanding the settings and practices that may lead to zoonotic pathogen spillover is of great global importance for developing countermeasures, and this study establishes bat roosts in buildings as such a setting. Many bat species share space with people and domestic animals. Bat use of buildings, which serve as roosts where they raise young and sleep, is increasing globally with the loss of natural habitat. In such settings, interactions between bats, people, and domestic animals may occur. This may be cause for concern as bats can carry pathogens that infect people or domestic animals and interactions with bats may create opportunities for exposure to these pathogens. Until now, the characteristics of human-bat interactions in buildings, and their potential for exposing humans and domestic animals to bat-borne parasites, were unknown. In our study, people living and working in buildings used simultaneously by bats reported frequent interactions with bats and their feces, which can facilitate human exposure to bat pathogens. These interactions happened frequently and over many years. We demonstrate that shared building use by bats and people in rural Kenya leads to prolonged, frequent, and sometimes intense interactions between bats, humans, and domestic animals, consistent with exposure opportunities that can lead to pathogen spillover. Identifying the settings that may lead to human contact with pathogens is critical for developing countermeasures to mitigate public health hazards.