A global evaluation of One Health

Thu, 02 Jan 2025 00:00:00 +0000

Human, animal and environmental health are often addressed separately, despite being deeply interconnected. This project uses a global One Health framework to ask how domestic animal disease and environmental change jointly shape infectious disease outbreaks in people.

I integrated 14,318 outbreak records for 206 human infectious diseases and 3,071,185 domestic animal disease events across 153 countries from 2005 to 2023. These records were combined with annual measures of tree-cover loss, urban expansion and temperature anomalies. Bayesian hierarchical models were used to estimate relationships within countries while accounting for population density, gross domestic product and reporting effort.

Human disease outbreaks were positively associated with domestic animal disease outbreaks, but environmental change was often the stronger predictor. A one-standard-deviation increase in tree-cover loss was associated with an estimated 22% increase in predicted human zoonotic outbreaks, compared with approximately 4% for an equivalent increase in domestic animal disease outbreaks. Urban expansion and temperature anomalies were also positively associated with zoonotic outbreaks.

These relationships varied among countries and disease types. The effects of animal disease, tree-cover loss and urban expansion were stronger in countries with larger populations and higher gross domestic product, whereas temperature anomalies had stronger effects where hospital capacity was lower. The results highlight the need to incorporate environmental indicators into disease surveillance and to tailor One Health policies to local ecological, socioeconomic and healthcare contexts.

Bayesian modelling | Zihui Wang

A global evaluation of One Health