Monitoring Killer Mice from Space

When I found the above title, I thought I'd be reading about a plague of deadly space mice and our efforts to keep track of them. No such luck. The story is actually about linking the satellite imagery of plant growth with the risk of contracting rodent-borne illness. After getting over my initial disappointment, I realized that the real study was interesting in its own right.

Denise Dearing and her colleagues from the University of Utah used the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on NASA's Terra satellite to generate satellite images of the plant life in Utah. Between 2003 and 2006, changes in vegetation were measured. Over an overlapping period of nine years, the researchers conducted twice yearly (spring and fall) trappings of deer mice, determining both the total number of mice and the percentage infected with hantavirus, a deadly pathogen. Hantavirus is acquired by breathing in the dried urine or feces of infected deer mice, and kills about half the people who contract it.

The scientists found that the amount of vegetation visible in the satellite images correlated very well with the total number of deer mice in an area. As the percentage of hantavirus-infected mice did not vary, more total mice meant proportionately more infected mice. Thus, the scientists were able to predict when people would be most at risk for encountering the disease.

The researchers suggest that this method could be used to create risk maps for other rodent-borne diseases. That would be pretty cool, but maybe not as cool as killer mice from space. Oh well.