Karen Libby
Pathogen Card

Sin Nombre Virus


Sin nombre virus (No-name virus in Spanish) is a member of the Hantavirus genus in the Bunyaviridae family, along with several other species, including Hantaan, Seoul, Puumala, and Prospect Hill. It is an enveloped, negative-sense, single-stranded RNA virus. Sin nombre replicates exclusively in the host cell cytoplasm, with entry thought to occur by receptor-mediated endocytosis. It was first isolated in the Four Corners Region of the United States.



HPS, caused by Sin nombre virus, is a rare disease but is frequently fatal, possessing a 50% mortality rate. The flu-like symptoms are very severe.


The virus is endemic to rodents, so it is spread to humans through contact with rodent droppings and urine. This can be accomplished by direct contact with excreta, aerosolization of urine, especially due to sweeping in rodent-infested homes, or contact with fomites, such as contaminated blankets or food storage areas. Most cases have been traced to inhabitants of closed, rodent-infested homes. A fever precedes other symptoms of myalgia, chills, headache, dizziness, cough, nausea, shortness of breath, and a cough. The patient's fluid eventually shifts from the circulation to the lungs, causing a high white blood count and a low platelet count. The prodromal period exists for 3-5 days from time of infection. Cough and shortness of breath generally develop by day 7. Once the cardiopulmonary phase begins, the disease progresses rapidly and hospitalization is generally required within 24 hours.


There is no vaccine against Sin nombre virus at this time. The best defense is proper hygiene and cleanliness. Rodents and their food sources must be eliminated from inside and anywhere near the home. All food and water should be stored in a rodent-proof metal container inside the home. Dishes should be washed immediately after use and put away in protected cupboards. Trash, clutter, and spills should be cleaned up immediately, covered in a rodent-proof container, and disposed. Rodent traps should be set within and around the home. Finally, care must also be taken to prevent rodents from gaining access to the home by sealing all openings, raising food sources, and keeping the area around the home free from woodpiles and other debris.

Game Action

See mice in your home, lose 3 life points


Small but deadly: Beware of mice in the home.


CDC: All About Hantaviruses