< < Back to the main Hantavirus in Yosemite page

The National Park Service continues its public health response and outreach as a result of confirmed cases of hantavirus pulmonary syndrome (HPS) in individuals who have spent one or more nights in Yosemite National Park since June of this year. Public health officials have linked the cases to the "Signature Tent Cabins" in Curry Village with one case potentially linked to the High Sierra Camps. The National Park Service Office of Public Health is working with the Centers for Disease Control and Prevention (CDC) and state public health offices to heighten public health awareness and detection of the disease.

Frequently Asked Questions About Hantavirus

What is hantavirus pulmonary syndrome?

Hantavirus pulmonary syndrome is a rare but serious disease that occurs throughout the United States and is caused by a virus that individuals get through contact with the urine, droppings, or saliva of infected rodents. Since HPS was first identified in 1993, there have been approximately 60 cases in California residents and 602 cases nationally. Nationwide, approximately 12 percent of deer mice carry hantavirus.

For additional information on preventing HPS, visit the CDC's hantavirus website at http://www.cdc.gov/hantavirus/index.html or call their hotline at 877/232-3322 or 404/639-1510.

---

What are common symptoms for hantavirus pulmonary syndrome?

According to the CDC, symptoms of HPS generally begin from one to five weeks after exposure. Early symptoms include fatigue, fever, chills, and muscle aches. About half of patients will experience headaches, nausea, vomiting, dizziness, and abdominal pain. The disease progresses rapidly (4-10 days after initial symptoms) to include coughing, shortness of breath, and severe difficulty breathing. Early medical attention greatly increases the chance of survival in cases of HPS. It is recommended that if a recent visitor to Yosemite National Park has any of the symptoms listed above, they seek medical attention immediately and advise their health care professional of the potential exposure to hantavirus. The types of hantavirus that cause HPS in the United States cannot be transmitted from one person to another.

---

How and where does one contract hantavirus pulmonary syndrome?

According to the CDC, cases of HPS occur sporadically, usually in rural areas where forests, fields, and farms offer suitable habitat for the virus's rodent hosts. Structures around homes (for example, barns, outbuildings, and sheds) are potential sites where people may be exposed to the virus. In the United States, deer mice (along with cotton rats and rice rats in the southeastern states and the white-footed mouse in the Northeast) carry the virus. The rodents shed the virus in their urine, droppings, and saliva. The virus is mainly transmitted to people when they breathe in air contaminated with the virus.

Anyone who comes into contact with rodents that carry hantavirus is at risk of HPS. Rodent infestation in and around the home remains the primary risk for hantavirus exposure.

---

What should I do if I think I have been exposed?

It is recommended that if a recent visitor to Yosemite National Park has any of the symptoms listed above, they seek medical attention immediately and advise their health care professional of the potential exposure to hantavirus.

---

Where can I get more information?

The park is updating its website (http://www.nps.gov/yose) daily with current information on confirmed cases and other additional information. The park is distributing hantavirus information to every visitor entering Yosemite and notices are posted throughout the park.

For additional information on preventing HPS, visit the CDC's hantavirus website at: http://www.cdc.gov/hantavirus/index.html or call their hotline at 877/232-3322 or 404/639-1510.

If you are a member of the media, please contact the Yosemite Public Affairs Office:

John Quinley or Victoria Mates 209/372-0248

---

What can I do to protect myself while in Yosemite or other areas around the U.S. where this has been found?

The park is a natural environment that contains wild animals, including rodents. All visitors should be aware of safety information related to visiting Yosemite, ranging from river safety to bear awareness and hantavirus awareness.

We do suggest that you are mindful of the steps that can be taken to reduce exposure to hantavirus. These include:

• Avoid touching live or dead rodents or disturbing rodent burrows, dens, or nests.
• Keep food in tightly sealed containers (including those stored in bear boxes) and store away from rodents.
• Take care not to stir up dust.
• Minimize storage of luggage and other materials on floors.
• Contact housekeeping or maintenance if signs of rodents are present, including feces or urine.
• Do not pitch tents or place sleeping bags in proximity to rodent feces or burrows or near possible rodent habitat (for example, dense brush or woodpiles).
• Avoid sleeping on bare ground. Use a cot with the sleeping surface at least 12 inches above the ground or use a tent with a floor.
• Dispose of all trash and garbage promptly in accordance with campsite regulations by burning, discarding in rodent-proof trash containers, or packing it out in rodent-proof containers.
• If visitors notice rodent droppings, they should contact staff immediately. National Park Service and concessioner staff are trained and equipped to respond to evidence of rodent activity.

---

What is the park doing to alert visitors about hantavirus?

Beginning in August, the park reached out via email, letters or phone calls to 30,000 guests who stayed in the Curry Village Signature Tent Cabins or High Sierra Camps since early June. We advised them of the symptoms of hantavirus and to seek medical attention if symptoms developed.

Since late August, visitors to the park have received written information on hantavirus and its prevention. Additional information has been posted throughout the park and on the Yosemite website.

After hearing from other concerned park visitors, on September 12 the park sent a public service email intended to reach 230,000 additional overnight guests who stayed in the park since early June. These visitors did not stay in the lodging areas linked to hantavirus or the High Sierra Camps. The message was to raise awareness about this rare disease.