Zoonotic pathogens in urban animals: Enough research to protect the health of the urban population?

Toward automating the diagnosis of gastrointestinal parasites in cats and dogs

Diagnosing gastrointestinal parasites by microscopy slide examination often leads to human interpretation errors, which may occur due to fatigue, lack of training and infrastructure, presence of artifacts (e.g., various types of cells, algae, yeasts), and other reasons. We have investigated the stages in automating the process to cope with the interpretation errors. This work presents advances in two stages focused on gastrointestinal parasites of cats and dogs: a new parasitological processing technique, named TF-Test VetPet, and a microscopy image analysis pipeline based on deep learning methods. TF-Test VetPet improves image quality by reducing cluttering (i.e., eliminating artifacts), which favors automated image analysis. The proposed pipeline can identify three species of parasites in cats and five in dogs, distinguishing them from fecal impurities with an average accuracy of 98,6%. We also make available the two datasets with images of parasites of dogs and cats, which were obtained by processing fecal smears with temporary staining using TF-Test VetPet.

Epidemiological connectivity between humans and animals across an urban landscape

Urbanization is predicted to be a key driver of disease emergence through human exposure to novel, animal-borne pathogens. However, while we suspect that urban landscapes are primed to expose people to novel animal-borne diseases, evidence for the mechanisms by which this occurs is lacking. To address this, we studied how bacterial genes are shared between wild animals, livestock, and humans (n = 1,428) across Nairobi, Kenya-one of the world's most rapidly developing cities. Applying a multilayer network framework, we show that low biodiversity (of both natural habitat and vertebrate wildlife communities), coupled with livestock management practices and more densely populated urban environments, promotes sharing of Escherichia coli-borne bacterial mobile genetic elements between animals and humans. These results provide empirical support for hypotheses linking resource provision, the biological simplification of urban landscapes, and human and livestock demography to urban dynamics of cross-species pathogen transmission at a landscape scale. Urban areas where high densities of people and livestock live in close association with synanthropes (species such as rodents that are more competent reservoirs for zoonotic pathogens) should be prioritized for disease surveillance and control.

Examining the paradox of urban disease ecology by linking the perspectives of Urban One Health and Ecology with Cities

The ecology of zoonotic, including vector-borne, diseases in urban social-ecological systems is influenced by complex interactions among human and environmental factors. Several characteristics contribute to the emergence and spread of infectious diseases in urban places, such as high human population densities, favorable habitat for vectors, and humans' close proximity to animals and their pathogens. On the other hand, urban living can contribute to the improvement of public health through better access to health services and creation of ecological and technological infrastructure that reduces disease burdens. Therefore, urbanization creates a disease ecology paradox through the interplay of urban health penalties and advantages for individual and community outcomes. To address this contradiction, we advocate a holistic Urban One Health perspective for managing urban systems, especially their green spaces and animal populations, in ways that more effectively control the spread of zoonotic diseases. This view should be coupled with an Ecology with Cities approach which emphasizes actionable science needed for urban planning, management and policymaking; developing disease and vector surveillance programs using citizen and community science methods; and improving education and communication actions that help diverse stakeholders understand the complexities of urban disease ecology. Such measures will enable scholars from many disciplines to collaborate with professionals, government officials, and others to tackle challenges of the urban disease paradox and create more sustainable, health-promoting environments.

Live and Wet Markets: Food Access versus the Risk of Disease Emergence

Emerging zoonotic diseases exert a significant burden on human health and have considerable socioeconomic impact worldwide. In Asia, live animals as well as animal products are commonly sold in informal markets. The interaction of humans, live domestic animals for sale, food products, and wild and scavenging animals, creates a risk for emerging infectious diseases. Such markets have been in the spotlight as sources of zoonotic viruses, for example, avian influenza viruses and coronaviruses, Here, we bring data together on the global impact of live and wet markets on the emergence of zoonotic diseases. We discuss how benefits can be maximized and risks minimized and conclude that current regulations should be implemented or revised, to mitigate the risk of new diseases emerging in the future.