Zoos are ideally placed to act as epidemiological monitoring stations because for decades, many have been building up detailed collections of serum banks, tissue banks and medical record-keeping systems that could be mined for information that would be beneficial to public health. For example, in 1999 wild Crows Corvus brachyrhynchos in the United States of America started to die of unknown causes but it was not until some died in the grounds of a zoological institution that West Nile virus, which is a threat to both human and animal health, was identified. There is a serious disparity in the type and amount of biosurveillance provided for humans, agricultural livestock and wildlife agencies, often driven by economic factors. There is an argument for public-health entities to contribute funds to the cost of managing serum-banks and testing stations within zoos to enhance biosurveillance in urban settings, in a cost-effective and mutually beneficial manner. The key to sustainable and integrated biosurveillance lies in public-health professionals working with zoo professionals, who care for wild animals on a day-to-day basis, to create electronic surveillance networks. This could be of utmost benefit to everyone.