Little Rock—The Health Department is continuing its surveillance for mosquito-borne viruses in the state and is testing dead birds and mosquitoes for the arboviruses responsible for Eastern Equine Encephalitis, St. Louis Encephalitis and West Nile Virus. Horses and other animals are also tested for West Nile Virus if they show signs of encephalitis. Human blood samples are being taken from patients with viral encephalitis and viral meningitis.

Dr. Tom McChesney, State Epidemiologist, says, "Arkansans should report dead birds to the local health unit, so that pick-up or delivery and testing of dead birds can be arranged." 

Mosquitoes are a problem to humans because they are annoying, can cause loss of productivity in livestock, and they may carry disease. Here are some facts about mosquitoes and the risks they pose to Arkansans:

• When mosquitoes feed on a bird or mammal, they may pick up a virus (arbovirus) along with the blood meal. These viruses are transmitted to humans through the bite of an infected mosquito. Not all mosquitoes have a virus in them, but certainly, the more mosquito bites one gets, the greater the risk of catching a disease. Most people that get bitten by an infected mosquito do not get sick. Those persons most at risk for getting sick include people with compromised immune systems, the elderly and very young children. There is no specific treatment for arboviral infections; avoiding mosquitoes is the best prevention.
 
• Symptoms of human arboviral infections typically begin within 14 days following the insect bite and consist of fever, headache, rash, muscle and joint aches, listlessness, and possibly encephalitis (swelling of the brain which is the most dangerous symptom).
  
• There are at least two different arboviruses that occur in Arkansas. They are Eastern Equine Encephalitis (EEE) and St. Louis Encephalitis (SLE). Another arbovirus is West Nile Virus (WNV). Currently, there is no West Nile Virus in Arkansas. It has moved as far as Louisiana, so potentially it could occur here.
 
• Humans, horses, pheasants, and emus are all very susceptible to Eastern Equine Encephalitis. Only a few human cases of EEE have ever occurred in Arkansas. Children are the most likely to have a serious illness. EEE is considered the most severe arboviral encephalitis; the fatality rate can approach 70 percent in susceptible people.
 
• St. Louis Encephalitis does not cause disease in animals; it is strictly a human disease. Large outbreaks of SLE have sporadically occurred throughout the U.S. The symptoms are typically milder, with most people experiencing flu-like symptoms. Those that are primarily affected are the elderly. Arkansas experiences sporadic cases of SLE, most going unreported. The largest outbreak in recent years was in 1991 in Pine Bluff, with 28 hospitalized and five of those, all over the age of 60, resulting in death.
  
• West Nile Virus was first recognized in the Western Hemisphere in the summer of 1999, when an outbreak occurred in the New York City area, infecting 62 people and causing seven deaths. Many different bird species and mammals, including 25 horses in New York also became infected. In 2000, the virus spread geographically; twelve states and the District of Columbia reported positive findings. As of August 2001, the virus has been detected as far south as Louisiana. There are no reports of WNV in Arkansas. West Nile Virus is like St. Louis Encephalitis in that most infected people do not get sick. Elderly individuals (fifty years and over) are at greater risk of developing severe illness and encephalitis. Symptoms include headache, fever, rash, stiff neck, muscle and joint pain, nausea, vomiting, diarrhea and neurological disease or encephalitis.
 
• Mosquitoes breed in any body of water, from small containers such as treeholes and tin cans, to large bodies of water like lakes or marshes. These breeding places create a variety of mosquito problems. To help stop mosquitoes from breeding, Arkansans should:
 
• Dispose of tin cans, plastic containers, ceramic pots or similar water-holding containers.
 
• Remove all discarded tires on your property.
 
• Drill holes in the bottoms of recycling containers that are kept outdoors.
 
• Make sure roof gutters drain properly and clean clogged gutters in the spring and fall.
 
• Turn over plastic wading pools and wheelbarrows when not in use.
 
• Change the water in bird baths.
 
• Clean vegetation and debris from the edges of ponds.
 
• Clean and chlorinate swimming pools, outdoor saunas and hot tubs.
 
• Drain water from pool covers.
 
• Use landscaping to eliminate stagnant water that collects on your property.
  
• To protect yourself and your family from mosquito bites, make sure all windows and doors have screens, which are in good repair. You should also stay indoors when mosquitoes are more active. When it is necessary to be outdoors, wear protective clothing and use mosquito repellent (containing 30 percent DEET). Use the following precautions when using repellents containing DEET:
 
• Store out of the reach of children and read all instructions on the label before applying.
  
• Do not allow young children to apply DEET themselves.
 
• Do not apply DEET directly to children. Apply to your own hands and then put it on the child, avoiding the child's face and hands.
 
• Avoid prolonged and excessive use of DEET.
 
• Do not apply repellents in enclosed areas.
 
• Do not apply directly to your face.
 
• Wash all treated skin and clothing after returning indoors.
 
• If you believe you or your child is having an adverse reaction to a repellent containing DEET, wash the treated area immediately and call your health care provider.

The Health Department is continuing to monitor the state with regard to mosquitoes and arboviruses. Health advisories will be issued if necessary. If West Nile Virus is found in Arkansas, the Health Department will immediately issue a health advisory and intensify mosquito control programs. 

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