About This Project

Leptospirosis is a disease that can be transmitted from animals to humans and is caused by bacteria called leptospires. Leptospires are capable of infecting most mammals, and rodents are a common reservoir. We would like to look for these bacteria in Alaskan rodents. Knowing the status of leptospirosis in Alaskan rodents will allow us to better understand the dynamics of this disease in the north, and to prepare for changes in the transmission of this disease that may occur with climate change.

Ask the Scientists

What is the context of this research?

The disease leptospirosis ("lepto") is caused by bacteria called leptospires. Leptospires are classified as zoonotic bacteria because they can be transmitted from animals to people. Leptospires are capable of infecting most mammals, and rodents are a common reservoir. In addition to infecting a wide variety of animals, leptospires can survive in water, and a common source of human exposure is water that has been contaminated by the urine of rodents or other animals. As the climate warms, there is likely to be more water on the Alaskan landscape. This may mean that humans and animals in Alaska are at increased risk for contracting lepto. It is important to know how prevalent leptospirosis is in Alaskan rodent populations to plan for managing this disease if it becomes more common.

What is the significance of this project?

The World Health Organization has classified leptospirosis as a “neglected tropical disease of global importance”. It is currently more common in tropical climates, but prevalence in temperate zones is rising and there are recent reports of it in the arctic and subarctic. Very little is known about lepto in the north. We have recently identified leptospiral DNA and antibodies in Alaskan caribou and reindeer, and think that rodents are likely acting as reservoirs. Determining its prevalence in rodents on farms where we have identified positive reindeer will give us valuable information about the ecology of this important global disease in Alaska, and will better allow us to make decisions on animal and human health in the state.

What are the goals of the project?

Our goal is to trap 50 rodents (northern red-backed voles, tundra voles, masked shrews, and meadow jumping mice) in and around farms where we have identified leptospirosis positive reindeer in Fairbanks, Alaska. We will collect blood and tissue samples from them and will attempt to identify DNA from leptospires (indicating current infection) and antibodies to leptospires (indicating an immune response to a past infection). We will then calculate disease prevalence. We will also correlate the presence of leptospiral DNA with antibody presence. This data will act as pilot data: between this project and previously mentioned caribou and reindeer data, we will have more data with which to design larger, more comprehensive studies of this important global zoonotic disease.

.