Mono County Health and Human Services has released a statement confirming the third hantavirus death in the town of Mammoth Lakes.

Hantavirus is a serious illness, and often fatal. People can get infected through contact with infected deer mouse droppings, urine, or saliva. Deer mice are common to the region.

Officials say they don't know where this third victim may have contracted the virus, since their home had no evidence of mouse activity.

According to Dr. Tom Boo, Public Health Officer for Mono County, none of the people in Mammoth Lakes who died of hantavirus were engaged in activities typically associated with exposure, such as cleaning out poorly-ventilated indoor areas, or places that typically have a lot of mouse waste.

Instead, they think these folks may have been exposed during normal daily activities.

Officials say that the public should be vigilant for signs of any indoor rodent activity.