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Date: 7/11/2007 

Number: PH07-03 

Contact: Suanne Buggy or Lea Brooks (916)-440-7259 


A Mono County man has been confirmed with hantavirus pulmonary syndrome (HPS), a disease spread by rodents, prompting California Department of Public Health Director Dr. Mark Horton to remind Californians to take precautions when entering cabins, trailers and other buildings infested with rodents to prevent exposure to the virus that causes the disease.

Public health officials from the state and Mono County are investigating how the man was exposed to the disease. He became ill in late June, but has recovered.

“Hantavirus pulmonary syndrome is a rare, but often fatal disease spread by rodents,” Horton said. “The chances of getting the virus are greatest when entering or cleaning enclosed spaces where wild rodents have been present.”

HPS is caused by a virus that individuals contract through contact with the urine, droppings or saliva of wild mice, primarily deer mice. Breathing small particles of mouse urine or droppings that have been stirred up into the air is the most common means of infection. The illness begins with fever, headache and muscle ache and progresses rapidly to severe difficulty breathing and, in some cases, death. Treatment for HPS depends upon the severity of an individual's symptoms. Prompt diagnosis and medical treatment increase an individual's chances of recovery.

Since HPS was first identified in 1993, there have been 48 cases in California and 465 cases nationally. About 33 percent of HPS cases identified in California have been fatal. In 2006, four cases of HPS were identified in California, three of which were fatal.

To prevent HPS, Horton recommended the following precautions:

  • Avoid areas, especially indoors, where wild rodents are likely to have been present.
  • Spray diluted bleach on areas contaminated with rodent droppings and urine. Wear plastic gloves and use a wet sponge or mop to clean the contaminated area. Do not sweep or vacuum. Place the waste in double plastic bags, each tightly sealed, and discard in the trash. Wash hands thoroughly afterward.
  • Do not touch or handle live rodents and wear gloves when handling dead rodents. Spray dead rodents with diluted bleach and dispose of in the same way as droppings. Wash hands thoroughly after handling dead rodents.
  • Keep rodents out of buildings by removing stacked wood, rubbish piles and discarded junk from around homes and sealing any holes where rodents could enter. Keep food in tightly sealed containers and store away from rodents.
  • If there are large numbers of rodents present in a home or other building, contact a pest control service to remove them.

For additional information about preventing HPS, please log on to the federal Centers for Disease Control and Prevention’s Web site at http://www.cdc.gov/ncidod/diseases/hanta/hps_stc/stc_spot.htm

Last modified on: 6/2/2009 10:15 AM