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Este pagina en espanolNorth Carolina Records First La Crosse Virus Case of 2009

Release Date: July 17, 2009
Contact: Carol Schriber, 919-733-9190, also Laura Leonard, DENR - Division of Environmental Health, 919-715-3204

RALEIGH – State public health officials today announced the season’s first case of the mosquito-borne illness La Crosse viral encephalitis (LAC).  The patient, who is from Henderson County, is now recovering at home.

“This case is an important reminder that we all need to take precautions to prevent mosquito bites,” said Acting State Epidemiologist Dr. Jean-Marie Maillard. “In addition to transmitting La Crosse and Eastern Equine Encephalitis, or EEE, mosquitoes found in North Carolina can be carriers of West Nile virus and other diseases. But, it is fairly easy for people to protect themselves from most mosquito bites by applying mosquito repellants and making their home or work environment less attractive to mosquitoes.”

Steps that people can take to make their homes less mosquito-friendly include:

  • Remove any containers that can hold water;
  • Keep gutters clean and in good repair;
  • Repair leaky outdoor faucets and change the water in bird baths and pet bowls at least twice a week; and
  • Check window and door screens.

These guidelines can be applied almost anywhere, such as work sites, church playgrounds and ball fields.

People can also protect themselves their families from mosquito bites by applying mosquito repellants to their skin and clothing. The CDC recommends several repellants, including DEET, picaridin, and oil of lemon eucalyptus. According to the CDC, oil of lemon eucalyptus should not be used on children under 3. Consumers should look for products that contain the CDC-recommended ingredients and follow all label instructions (

People can also “fight the bite” by wearing light-colored long pants and long-sleeved shirts and by reducing time spent in mosquito-infested areas outdoors, particularly in early morning and early evening hours when mosquitoes are most active.

Although no human cases of EEE have been documented this year, mosquito-borne transmission of the virus has been seen in chickens through sentinel flock surveillance in several eastern North Carolina counties.

Symptoms of La Crosse in people occur from a few days to a couple of weeks after being bitten by an infected mosquito. These symptoms include fever, headache, nausea and vomiting. In more severe cases, convulsions, tremors and coma can occur. Children under 16 years of age and the elderly are the most susceptible to the disease.

While other mosquito-borne diseases like West Nile virus are found across the state, La Crosse encephalitis is largely confined to western North Carolina and is the state’s most common mosquito-borne disease. State officials recorded 8 LAC cases in 2008. The Centers for Disease Control and Prevention records about 70 cases in the U.S. each year.  The disease is rarely fatal, but a Transylvania County child died as a result of infection in 2001. LAC can have long-lasting negative effects on a person’s health, so prevention is especially important.

For additional information regarding mosquitoes and ticks, see the following Public Health web sites: and




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