Hantavirus Outbreak in Yosemite National Park

Tent cabins in the Curry Village campgrounds in the Yosemite National Park, California.
Tent cabins in the Curry Village campgrounds in the Yosemite National Park, California.

The California Department of Public Health have reported a total of  six cases  of the mouse -borne hantavirus infection among previous visitors of Yosemite National Park in California, four of which have been successfully treated while two have, unfortunately, died  of the lung virus. The last victim,whose name has not been released, died in late July and had camped in the California park’s Curry Village Campground, where hantavirus has been detected in deer mice.

Tent cabins in the Curry Village campgrounds in the Yosemite National Park, California. (photo credit from http://www.worldofstock.com)
Tent cabins in the Curry Village campgrounds in the Yosemite National Park, California. (photo credits from http://www.worldofstock.com)
There were previous reports of hantavirus infection from the park in the years 2000 and 2010, but no casualties were reported.

Park officials have reported the outbreak of the deadly, mouse-born hantavirus to instill awareness among people, hoping to stop the spread of the virus. The U.S. Centers for Disease Control and Prevention have noted that around 10,000 people who stayed in tent cabins at the park from the months June to August may have contracted the disease. The CDC added that it is investigating more cases that could be linked to the outbreak.

The hantavirus is spread by Hantavirus Pulmonary Syndrome (HPS) infected rodents. Although rare, it is potentially deadly. The virus is spread through rodent droppings, urine and saliva, which dries out and mixes with dust that can be inhaled by humans, especially in small, confined spaces with poor ventilation. People can also be infected by eating contaminated food, touching contaminated surfaces or being bitten by infected rodents.

Symptoms can show within one to six weeks after exposure. The disease is manifested by early symptoms like fever, vomiting, muscle aches, headaches, chills, nausea, diarrhea, abdominal pain and coughing and progresses rapidly rapidly to severe difficulty in breathing and, in some cases, death.

To this date, there is no specific treatment for the virus, and about one-third of people who contract it will die, though treatment after early detection through blood tests can save lives.

HPS cannot be transmitted from one person to another. The virus does not spread from touching or kissing a person who has the virus or from a health care worker who has treated someone with the disease. You can’t contract HPS by receiving blood transfusion from a person who survived the disease.

The length of time hantavirus can remain infectious in the environment varies and will and depend on environmental conditions like temperature and humidity;whether the virus is indoors or outdoors or exposed to the sun; and even on the rodent’s diet , which would affect the chemistry of its urine. At normal room temperature, viability if the virus can remain from 2 to 3 days. Exposure to sunlight will decrease the time of viability as freezing temperatures can increase the time that the virus remains viable.

The first way to prevent HPS is to avoid contacts with rodents. Rodent proof  your house by sanitizing your residence. Store garbage in rodent-proof containers. Never leave trash bins uncovered. If you have pets, ensure that garbage cans have tight fitting lids so your pets or other wildlife can’t tip them. Clean up spilled or unconsumed food as soon as possible. Their food should not be exposed, as these may lead to that rodents. Also, clean up pet excrement, as rats will eat it if they have to. Outdoors, do not scatter or leave food for wildlife consumption. Clean up fallen fruits or nuts from trees.

Seal up rodent entry holes or gaps with steel wool, lath metal, or caulk. Repair broken windows, doors and broken sewers.

Clean up rodent food sources and nesting sites and take precautions when cleaning rodent-infested areas. Do the following:

  • Put on rubber, latex, vinyl or nitrile gloves.
  • Do not stir up dust by vacuuming, sweeping, or any other means.
  • Thoroughly wet contaminated areas with a bleach solution or household disinfectant. Use hypochlorite (bleach) solution: Mix 1 and ½ cups of household bleach in 1 gallon of water.
  • Once everything is wet, take up contaminated materials with damp towel and then mop or sponge the area with bleach solution or household disinfectant.
  • Spray dead rodents with disinfectant and then double-bag along with all cleaning materials. Bury, burn, or throw out rodent in appropriate waste disposal system. (Contact your local or state health department concerning other appropriate disposal methods .)
  • Disinfect gloves with disinfectant or soap and water before taking them off.
  • After taking off the clean gloves, thoroughly wash hands with soap and warm water.

Web References:

http://edition.cnn.com/2012/08/30/health/california-yosemite-hantavirus/index.html

http://wellbody.net/2012/08/18/of-rats-and-the-diseases-they-bring/

http://health.usnews.com/health-news/news/articles/2012/08/31/basics-about-hantavirus-outbreak-in-yosemite

http://www.contracostatimes.com/news/ci_21431326/yosemite-hantavirus-warning-could-be-expanded-other-countries

http://www.azdhs.gov/phs/oids/vector/hps/files/cdc_hps_what_you_need_to_know.pdf