Why are only a few rodent species considered serious pests or disease carriers?

Only a small fraction of rodent species are considered serious pests or disease carriers because only those few species possess the specific genetic and behavioral traits necessary to adapt to human-altered environments.1

While most rodents live independently of humans, species such as the house mouse and rat have evolved to exploit human settlements as reliable sources of food and shelter. These synanthropic rodents are highly prolific, allowing their populations to thrive in close proximity to people. Because they live in such intimate association with human populations, they frequently act as reservoirs for diseases—such as plague, murine typhus, and Lassa fever—and cause significant damage to crops and infrastructure. In contrast, the vast majority of the world's rodent species remain in wild habitats, where they play diverse ecological roles and do not interact with humans in ways that facilitate the spread of pests or pathogens.12