Trending Now - Study Reveals Increased Hantavirus Threat in US Rodents
WHO:
Fox News - Researchers from Washington State University's College of Veterinary Medicine conducted the study.
Fox News - Stephanie Seifert is the study's corresponding author and principal investigator of the Molecular Ecology of Zoonotic and Animal Pathogens lab.
Fox News - Dr. Sonja Bartolome is an expert in pulmonary and critical care at UT Southwestern Medical Center.
KOMO - Pilar Fernandez is a co-author on the study and a disease ecologist in the Allen School.
WHAT:
Fox News - The study suggests that Sin Nombre virus may be more widespread in the region than previously thought, with infections found across multiple rodent species.
KOMO - The study produced the first full genome sequences of Sin Nombre virus strains from the Northwest, showing high levels of genetic diversity and evidence of viral reassortment.
KOMO - Researchers indicated that human infections remain rare, suggesting that some infections may go unnoticed.
Fox News - The study found that nearly 30% of sampled rodents showed evidence of prior exposure to the Sin Nombre virus, and about 10% had active infections.
KOMO - The study revealed that Sin Nombre virus, which causes hantavirus pulmonary syndrome, is more common in rodent populations than previously recognized.
KOMO - A total of 864 hantavirus cases were reported in the U.S. from 1993 to 2022, with a 36% case-fatality rate.
KOMO - 109 of those cases occurred in Idaho, Oregon, and Washington.
WHERE:
Fox News - The study focused on the Palouse region, which includes parts of eastern Washington and north-central Idaho.
KOMO - Fieldwork was conducted in Whitman County, Washington, and Latah and Benewah counties in Idaho.
WHEN:
Fox News - The fieldwork for the study was conducted in summer 2023.
KOMO - The findings were published in 2026 in the journal Emerging Infectious Diseases.
WHY:
Fox News - Researchers hope to expand the work if additional funding becomes available, including studying how often people are exposed and how human behavior influences risk.
Fox News - Researchers were surprised by the commonality of the virus locally and the lack of existing data for the Northwest.
KOMO - The study aims to understand how the virus spreads and the potential for human exposure.
HOW:
KOMO - The researchers recommend taking precautions when cleaning areas where rodents may have been present, as activities that disturb droppings or nests can increase the risk of exposure.
Fox News - Researchers collected samples from 189 deer mice, voles, and chipmunks at eight farms and two forest sites.
KOMO - The study produced the first full genome sequences of Sin Nombre virus strains from the Northwest, showing high levels of genetic diversity and evidence of viral reassortment.
(UPDATED May 22, 2026 17:36 UTC)
A new study suggests that the Sin Nombre virus may be more widespread in the region than previously thought, with infections identified across various rodent species and the first full genome sequences revealing high levels of genetic diversity. Researchers emphasize that while human infections remain rare, some cases could go unnoticed, and they hope to expand their work if additional funding becomes available to better understand exposure risks. They recommend taking precautions when cleaning areas where rodents may have been present, as disturbing droppings or nests can heighten the risk of exposure.
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(UPDATED May 22, 2026 11:59 UTC)
A recent study conducted by researchers at Washington State University's College of Veterinary Medicine has revealed that nearly 30% of sampled rodents in the Palouse region, which includes parts of eastern Washington and north-central Idaho, showed evidence of prior exposure to the Sin Nombre virus, with about 10% having active infections. The findings, published in 2026 in the journal Emerging Infectious Diseases, indicate that this virus, which causes hantavirus pulmonary syndrome, is more prevalent in local rodent populations than previously recognized, with a total of 864 hantavirus cases reported in the U.S. from 1993 to 2022. Researchers collected samples from 189 deer mice, voles, and chipmunks, producing the first full genome sequences of Sin Nombre virus strains from the Northwest, highlighting significant genetic diversity and evidence of viral reassortment.