Bats and Rabies Research in Fort Collins

Transmission of rabies occurs through biting by infected mammals. In the United States rabies is now primarily a disease of wildlife, particularly small carnivores such as skunks, foxes, and raccoons. Unlike many other states, in Colorado rabies is found almost exclusively in bats. Public health monitoring has shown that people and domestic animals in Colorado are most often exposed to rabies by contact with bats in cities and towns.


Big brown bat

The big brown bat (Eptesicus fuscus) is the species most commonly associated with potential exposures to rabies in Colorado, and this species also is the bat most commonly submitted for rabies testing throughout the United States. Deaths of humans from rabies associated with bites of big brown bats or any other species of bat in the U.S. are extremely rare, due in part to the active public health surveillance system and the highly effective post-exposure prophylaxis ("rabies shots"). However, rabies is almost universally fatal in infected humans that are not treated with post-exposure prophylaxis. Despite the presence of this deadly disease in big brown bats in towns and cities of the U.S. and Colorado, surprisingly little detailed scientific information is known about the ecology of this species of bat where it lives in close proximity to humans. Similarly, nothing is known about the true frequencies of rabies in these bats, how often they are exposed to the disease, and how the disease cycles and maintains itself in city-dwelling bat populations.

We studied the ecology of big brown bats in relation to rabies in Fort Collins between 2001 and 2006. This city was selected because it is representative of many cities and towns in Colorado (and many other states) in that big brown bats appeared to be the dominant species of bat, and big brown bats were commonly submitted to state and local public health agencies for rabies testing. Like many western cities, Fort Collins is located in a river valley. Fort Collins is also experiencing rapid man-made changes due to extensive urban development and regional sprawl, perhaps providing numerous potential roosts for bats in an area that prior to human settlement was an arid short-grass prairie unsuitable for these animals. We also selected Fort Collins because of the presence of active bat researchers, biomedical experts, and ecologists in the area. This provided us with a team that could study bats and rabies literally in our own back yards, without the need for extensive travel and other logistic expenses. Currently we are no longer conducting research by capturing and sampling bats in the field, but are in the final phases of data analysis, modeling, and publishing results.

Sponsoring Organizations

This study was carried out by scientists from Colorado State University in collaboration with the U.S. Geological Survey's Fort Collins Science Center, and the Centers for Disease Control and Prevention, Atlanta.

Major funding support is provided by the National Science Foundation and National Institutes of Health, through their joint Ecology of Infectious Diseases Program. We also involve numerous students in various biological, ecological, and veterinary medicine programs at Colorado State University.

Links to Information on Rabies

CDC Rabies Homepage

Colorado Department of Health & Environment

Fort Collins Bat Project

Study Objectives

Bats in the Fort Collins Area

Rabies in Local Bat Populations

Survival & Reproduction in Big Brown Bats

Occupancy of Buildings by Bats

Bat Movements & Foraging

Migration and Hibernacula of Big Brown Bats in Colorado

Genetics and Life History Traits of Big Brown Bats

Ectoparasites of Big Brown Bats

Project Personnel

Project Publications

Links To Other Sites

U.S. Geological Survey Fort Collins Science Center

Bat Conservation International

Colorado Bat Society

Western Bat Working Group

Fort Collins Natural Areas

Organization for Bat Conservation

Larimer Country Health & Environment