Global surveillance of anthrax outbreaks in domestic animals and humans: A retrospective secondary analysis of reported cases over two decades (2005–2024)

Anthrax, caused by Bacillus anthracis , remains a significant concern in animal and public health globally. This study examines anthrax outbreak data from 2005 to 2024, utilizing reports from the World Animal Health Information System (WAHIS) and ProMED. Our analysis reveals a general decreasing trend in global anthrax incidents, with persistent endemicity in regions of Central Asia, Africa, and Southern Asia. Despite this overall decline, Türkiye maintains similar levels of anthrax incidents in livestock, while six countries demonstrate increasing trends during the studied period, a finding broadly supported by sensitivity analysis. Additionally, unexpected emergence in historically low-incidence regions demonstrates the disease's unpredictable nature. The study identifies cattle and sheep as primary hosts, underscoring their role in disease ecology. Importantly, we observe differences in reporting patterns between countries with high livestock incidence and those documenting human cases, which may reflect differential surveillance capacity, underreporting of human cases, or genuine epidemiological variation in zoonotic transmission dynamics. Notable differences between WAHIS and ProMED reports potentially reflect that animal surveillance systems and human health alert networks capture different aspects of anthrax outbreaks, underscoring the value of cross sectoral data synthesis to achieve a more comprehensive epidemiological understanding to inform risk mitigation measures.