What is hantavirus?

Hantavirus is a virus that spreads through the urine, droppings (poop), or saliva of wild rodents, including deer mice, which are common in many parts of California. Hantavirus can cause serious disease in humans.

How can a person become infected with hantavirus?

People can become infected with hantavirus when they breathe in air that is contaminated with the virus. Particles containing hantavirus get into the air when dried mouse urine, saliva, or droppings are stirred up. The chances of this happening increase when opening or cleaning buildings in rural areas that have been closed for the winter where deer mice have entered, or for people working, playing, or living in closed spaces where mice are present.

Symptoms of hantavirus infection can be mild or severe, depending on whether a person's lungs become infected. There is no specific treatment for hantavirus infection, but early medical care can help if serious disease develops. 

How can I help p​revent hantavirus infection?

Because hantavirus infection can be serious, even deadly, it is important to know how to prevent it. The best way to prevent hantavirus infection is to keep wild rodents, especially mice, out of your home, workplace, cabin, shed, car, camper, or other closed space:

• Seal up holes (the width of a pencil or larger) and other openings where mice can get in.
  

• Place snap traps to catch any mice (do not use glue traps or live traps).
  

• Store all food items in rodent-proof containers to keep mice away.
  

​​Learn more: ​​ How to Seal Up to Prevent Rodents​

If you find sign​​s of mice o​​r other rodents, it’s important to clean up after them safely to reduce your chances of getting sick:

​​​Before you start cleaning

• Gather the proper supplies, including rubber or plastic gloves and a disinfectant or bleach solution made from a mixture of household bleach and water.
  

• Air out the space you will be cleaning for 30 minutes​.
  

While cleaning (wear gloves)

• Spray the contaminated area with the disinfectant or bleach solution until very wet, and let it soak for at least 5 minutes.
  

• Use paper towels, a sponge, or mop to clean up the contaminated area.
  

Key Messages for Reducing Hantavirus Risks

Click an image to view and download (right-click and select “Save image as”).​

English:  ​​​​If you need to clean out an area where rodents have made a nest, be careful not to stir up dust or droppings. Deer mice in California can be infected with hantavirus, which can spread to people through the air. Learn more: go.cdph.ca.gov/hantaviru​s Spanish:  Si tiene que limpiar una zona donde los roedores han hecho un nido, tenga cuidado de no dispersar polvo ni excrementos. Los ratones ciervo de California pueden estar infectados por el hantavirus, que puede contagiarse a las personas a través del aire. Obtenga más información:  https://www.cdph.ca.gov/Programs/CID/ DCDC/Pages/Hantavirus-es.aspx​​​
​Englis​​h:  ​​Before cleaning an area infested by mice, air out the space for 30 minutes. Then use a mop or sponge and a freshly made 10% bleach solution to clean the area. Wear gloves while cleaning, and consider wearing a respirator (face mask) if cleaning heavily infested areas. Learn more: https://www.cdc.gov/healthy-pets/rodent-control/clean-up.html Spanis​​h:  ​​Antes de limpiar una zona infestada de ratones, ventile el espacio durante 30 minutos. A continuación, utilice un trapeador o una esponja y una solución de lejía al 10 % recién preparada para limpiar la zona. Utilice guantes mientras limpia y considere la posibilidad de usar una mascarilla (protector facial) si limpia zonas muy infestadas. Obtenga más información:  https://www.cdph.ca.gov/Programs/CID/ DCDC/Pages/Hantavirus-es.aspx​​
E​​nglish:  ​​Buildings and cabins that have been closed for the winter or other long periods can be home to mice and other rodents. Deer mice can be infected with hantavirus, which can be spread to people through the air in closed spaces. If you need to clean an area contaminated with mouse droppings or nests, follow these steps: https://www.cdc.gov/healthy-pets/rodent-control/clean-up.html ​Spanish:  ​En los edificios y las cabañas que han estado cerrados durante el invierno u otros períodos prolongados, puede haber ratones y otros roedores. Los ratones ciervo pueden estar infectados por el hantavirus, que puede contagiarse a las personas a través del aire en espacios cerrados. Si tiene que limpiar una zona contaminada con excrementos o nidos de ratón, siga estos pasos (en inglés): https://www.cdc.gov/healthy-pets/rodent-control/clean-up.html​ ​
Engli​sh:  Before you open a building that’s been closed for a long time, air out the space for 30+ minutes and clean only with a wet mop or sponge. Sweeping or vacuuming stirs up mouse droppings and other rodent-contaminated materials that can spread hantavirus in the air. Learn more: ​https://bit.ly/PreventHPSAtWork Spani​​sh: ​Antes de abrir un edificio que ha estado cerrado durante mucho tiempo, ventile el espacio durante más de 30 minutos y límpielo solo con un trapeador o una esponja húmedos. Si barre o aspira, se levantan excrementos de ratón y otros materiales contaminados por roedores que pueden propagar el hantavirus en el aire. Obtenga más información:  https://www.cdph.ca.gov/Programs/CID/ DCDC/Pages/Hantavirus-es.aspx​​​​