Zoonotic host diversity increases in human-dominated ecosystems.

Area of Science:

• Ecology
• Epidemiology
• Conservation Biology

Background:

• Land use change, such as habitat conversion to agriculture or urban areas, is linked to zoonotic disease emergence.
• Predictable ecological shifts in wildlife host communities due to land use change remain poorly understood.

Purpose of the Study:

• To investigate the global, systematic effects of land use on local zoonotic host communities.
• To determine if land use change predictably alters the diversity and abundance of wildlife species that can transmit diseases to humans.

Main Methods:

• Analysis of 6,801 ecological assemblages and 376 host species globally.
• Control for research effort to ensure robust findings.
• Comparison of zoonotic host communities in human-used ecosystems versus undisturbed habitats.

Main Results:

• Land use has significant, global impacts on zoonotic host communities.
• Known wildlife zoonotic hosts are disproportionately abundant (21-144% higher) and rich (18-72% higher) in human-used sites (secondary, agricultural, urban) compared to undisturbed areas.
• Rodents, bats, and passerine birds showed the strongest increases in human-used areas, highlighting their role as key zoonotic reservoirs.

Conclusions:

• Global land use changes systematically favor species that act as reservoirs for zoonotic diseases.
• Ecological and life-history traits likely mediate host susceptibility and tolerance to human disturbance, influencing pathogen spillover risk.
• Intensified land use creates expanding interfaces between humans, livestock, and wildlife, increasing the risk of zoonotic disease emergence.