Epidemiology and Ecology of Bacillus anthracis

Bacillus anthracis, the causative agent of anthrax, is a spore-forming bacterium that persists in diverse ecosystems, triggering disease outbreaks in herbivores and occasional spillover into human populations. The lifecycle of B. anthracis is tightly linked to soil and sediment reservoirs where dormant spores survive adverse conditions and germinate under favourable environmental cues. Wild and domestic grazing animals contact contaminated soils during foraging, leading to ingestion or inhalation of spores, with subsequent contamination of the environment through carcasses that release vast numbers of spores back into the soil. Human cases often follow occupational or environmental exposure at the livestock–wildlife interface, underscoring anthrax as a quintessential zoonosis. Epidemiological patterns vary geographically: tropical savannahs, temperate grasslands and arid regions each exhibit distinct seasonality driven by rainfall, temperature and land use. Climatic change can alter spore viability and host susceptibility, reshaping anthrax risk across latitudes. Advances in molecular typing and modelling have refined our understanding of transmission dynamics, revealing the role of global trade and animal movements in spore dispersal. A One Health approach integrating human, animal and environmental health is essential to design targeted surveillance, vaccination and vegetation management strategies, and to mitigate the enduring public health and economic burden of anthrax worldwide.

Research from Nature Portfolio

Recent studies have applied machine learning to predict anthrax suitability across northern latitudes by integrating temperature trends, livestock densities and wild ungulate diversity. These models have demonstrated that rising temperatures significantly expand the ecological niche of B. anthracis in permafrost and boreal regions, highlighting the need for proactive animal health measures among small and mid-size herds. Complementary field investigations have quantified pathogen concentrations at carcass sites and waterholes over multiple years, confirming that grazing at one- to two-year old carcass sites poses the highest risk of lethal exposure. Such work underscores that not all environmental reservoirs contribute equally to transmission and that targeted carcass disposal and habitat management can disrupt local transmission cycles.

Epidemiology and Ecology of Bacillus anthracis publication trend

The graph below shows the total number of articles in epidemiology and ecology of bacillus anthracis across all publications each year (not limited to Nature Index journals).

Technical terms

Bacillus anthracis: Gram-positive, spore-forming bacterium responsible for anthrax.

Spore: Dormant, highly resistant bacterial form enabling long-term environmental survival.

Zoonosis: Infectious disease transmitted between animals and humans.

Phylogenetic analysis: Comparative study of genetic relationships among microbial isolates.

One Health: Integrated strategy recognising interdependence of human, animal and environmental health.

Environmental reservoir: Natural habitat where pathogens persist outside a host, sustaining transmission.

References

1. Molecular characterization of an outbreak-involved Bacillus anthracis strain confirms the spillover of anthrax from West Africa. Infectious Diseases of Poverty (2024).
2. Retrospective Analysis of Official Data on Anthrax in Europe with a Special Reference to Ukraine. Microorganisms (2023).
3. An integrated model for anthrax-free zone development in developing countries. Journal of Infection and Public Health (2023).
4. Climatic influence on anthrax suitability in warming northern latitudes. Scientific Reports (2018).
5. Lethal exposure: An integrated approach to pathogen transmission via environmental reservoirs. Scientific Reports (2016).