Decline of aspens swells population of rodents that carry sin nombre virus

Susan Milius in Science News: Recent diebacks of aspen trees in the U.S. West may end up increasing the risk posed by a lethal human pathogen, a new study suggests. A tree-killing syndrome called sudden aspen decline that has wiped out swaths of trees across the West in the past decade has also changed the kinds, numbers and interactions of creatures living around the trees, researchers have found — including some carriers of human disease. Deer mice at hard-hit sites in 2009 were almost three times as likely to carry sin nombre virus — which can be fatal to humans — compared with mice in less-ravaged aspen stands, Erin Lehmer of Fort Lewis College in Durango, Colo., and her colleagues reported January 4 at the annual meeting of the Society for Integrative and Comparative Biology.

The deer mouse Peromyscus maniculatus looks ironically cute in pictures at meeting presentations, but the Centers for Disease Control and Prevention ranks it as the main rodent reservoir for sin nombre virus. Infected deer mice don’t show many symptoms, but people inhaling virus wafting from mouse urine or saliva can get quite sick with hantavirus pulmonary syndrome.

…“Both plant diseases and animal diseases are rapidly emerging globally, and we should be looking for ways that the two might interact,” said Richard Ostfeld of the Cary Institute of Ecosystem Studies in Millbrook, N.Y., who studies Lyme disease transmission….

Transmission electron micrograph of the Sin Nombre Hantavirus. Hantaviruses that cause Hantavirus pulmonary syndrome (HPS) are carried in rodent droppings, especially the deer mouse. Centers for Disease Control