New Washington Hantavirus Case Confirmed In Issaquah

ISSAQUAH, WA - King County health officials confirmed Thursday that an Issaquah woman in her 50s is the third person from the county to contract the deadly deer mouse-transmitted hantavirus pulmonary syndrome since December. The Issaquah woman is being treated at a local hospital and is reportedly in stable condition. She is the second person from Issaquah to contract Hantavirus this year.

Since December, two other King County residents have contracted hantavirus. One, a man in his 30s from Issaquah, died in February. He and the woman currently being treated both lived in the Squak Mountain area, but health officials do not believe the cases are connected. By that, health officials mean that the infections did not come from the same mouse; humans cannot transmit the virus.

With the confirmation of a third case, health officials are referring to the cases as a "cluster," and that means that there could be increased risk in wooded suburban areas. The first case, confirmed in December, was in a Redmond woman who may have come into contact with deer mice living in her car's air filter.

"There is potentially an increased risk for hantavirus this season," Dr. Meagan Kay, a county medical epidemiologist, said Thursday.

The county held a live Q&A about the virus on Thursday. You can watch the entire video here:

In Western Washington, only deer mice carry hantavirus. Humans contract the virus by coming into contact with feces and urine. The disease tends to spread easier in arid climates because virus particles can travel through the air more easily.

Meanwhile, data from the Centers for Disease Control show that Washington is one of the top states in the U.S. for hantavirus cases. According to the data, Washington has had 46 cases since the virus was identified in 1993, behind only New Mexico (100), Colorado (94), Arizona (74), and California (62).

These recent infections are the first in King County since 2007, according to state records. Since 1993, a total of six hantavirus infections have originated in the county, the most for a single county west of the Cascades. Infections appeared to be more common in Eastern Washington counties like Lincoln, Grant, and Yakima.

The state Department of Health provided Patch.com data on the number of cases by county of origin since 1993.

Hantavirus was identified in 1993 after an outbreak in the Southwest in the four corners area near Utah, Colorado, New Mexico, and Arizona. The disease is very deadly, with a mortality rate of about 38 percent, according to the Centers for Disease Control. Seasonal flu, by comparison, has a mortality rate of about 2.5 percent.

After the initial outbreak in 1993, researchers theorized that a wetter-than-usual winter contributed to an increase in the population of rodents that carry hantavirus there. King County is working with state ecology officials to figure out if a similar change in weather or habitat has contributed to these recent cases.
Kay said that wet weather may be a factor, driving mice closer to human areas. The rain might also create more food sources for deer mice.

Hantavirus may begin with similar symptoms to flu, including fever, muscle aches, and chills. Later, the disease causes the lungs to fill with fluid. There is no specific treatment for the virus, and no vaccine. Humans cannot spread the disease between each other.

Kay warned that anyone with symptoms needs to seek treatment as early as possible. It's also important to inform your doctor if you've been in contact with deer mice.

Health officials warned that pets can bring hantavirus into a home if they come in contact with an infected mouse or bring one into the home. It's important to remember, only deer mice in the area carry hantavirus - rats and mice found in urban areas do not carry it.

Image via Patch.com