In February, a man from Issaquah in his 30s contracted hantavirus and subsequently died. Both cases lived near Squak Mountain but in different neighborhoods. Last November, a woman was exposed to deer mice near her home in Redmond. She contracted HPS, but survived.
Public Health – Seattle & King County does not believe the two cases in Issaquah are related, but there are reports of increased numbers of deer mice seen in the area.
Hantavirus is a rare disease in Washington State. Before 2016, the last case of hantavirus infection acquired in King County was in 2003.
In Washington, the only rodents that spread hantavirus are deer mice. They have distinctive white underbellies and white sides. They are only distantly related to the common house mouse. Rats do not spread hantavirus in Washington
Deer mice do not live in urban settings in Washington, but prefer woodland areas such as the suburban foothills.
A person gets HPS by breathing in hantavirus. This can happen when dust from dried rodent urine, saliva and droppings that contain hantavirus are stirred up in the air. The disease does not spread person-to-person.
People can also get infected by touching rodent urine, droppings or nesting materials that contain the virus, and then touching their eyes, nose or mouth. It's also possible to get HPS from a rodent bite.
If the current suspect case is confirmed as HPS, Public Health – Seattle & King will continue investigating how and where this woman most likely became infected.
Health officials will be consulting with the Washington State Department of Fish and Wildlife (WDFW) to provide information on the ecology of deer mice locally, including whether there have been any changes either to the population of deer mice or to the prevalence of the hantavirus in the deer mice, and whether changes may be impacting the threat to humans.
The agency is also consulting with the Centers for Disease Control and Prevention, and the Washington State Department of Health.
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