The One Health framework links animal, human, and environmental health, and focuses on emerging zoonotic pathogens. Understanding the interface between wildlife and human activity is critical due to the unpredictable nature of spillover of zoonotic pathogens from animals to humans. Zoos are important partners in One Health because of their contributions to education, conservation, and animal health monitoring. In addition, the housing of wildlife in captive and semi-natural settings makes zoos, especially relevant for detecting animal-related pathogens. A first step to determine the utility of zoos in contributing to pathogen surveillance is to survey the peer-reviewed literature. We, therefore, retrieved data from the previous 20 years and performed a meta-analysis to determine global patterns of viral seroprevalence in mammals housed in zoo collections from peer-reviewed literature. We analysed 50 articles, representing a total of 11,300 terrestrial mammals. Increased prevalence was found in viruses strictly targeting specific host taxonomy, especially in viruses transmitted through direct contact. Potentially complex patterns with geography were also identified, despite uneven sampling. This research highlights the role zoos could play in public health and encourages future standardized epidemiological surveillance of zoological collections.