Fremont County West Nile Virus Infections Climb Sharply

August 29 , 2006

FOR IMMEDIATE RELEASE
Tuesday, August 29, 2006
Contact: Kim Deti
Phone: 307-777-6420

Fremont County West Nile Virus Infections Climb Sharply

CHEYENNE - As Wyoming West Nile virus infections continue to climb, state Department of Health officials said lab tests have confirmed that six more Fremont County residents have been infected.

The new cases bring the total number of human West Nile virus infections in Wyoming for 2006 to 12, with 10 of those in Fremont County. Wyoming had 12 human cases for all of 2005.

“The sudden increase of West Nile cases in Fremont County is unexpected,” said Kelly Weidenbach, surveillance epidemiologist with the Wyoming Department of Health. “We are not certain why the number of cases is going up in this county and not in other areas.”

Two elderly men are hospitalized as a result of the virus, and an older woman was hospitalized and released. In addition, a young girl experienced headache, fever and fatigue after being infected earlier this month. One woman reported headache, fatigue, rash and muscle aches and another reported high fever and rash.

“West Nile virus can be dangerous -- even deadly,” said Dr. Brent Sherard, Wyoming Department of Health director. “My department has seen a stepped-up level of West Nile activity over the last two weeks, especially in Fremont County, and we’re urging people to take precautions against mosquito bites.”

Mosquitoes spread West Nile virus after they feed on infected birds and then bite people, other birds and animals.

Sherard suggested that people follow the “5 D’s” of West Nile virus prevention:
1) DAWN and 2) DUSK - Most mosquitos prefer to feed at dawn or dusk, so avoid spending time outside during these times.
3) DRESS - Wear shoes, socks, long pants, and a long-sleeved shirt when spending time outdoors. Clothing should be light-colored and made of tightly woven material
4) DRAIN - Mosquitos breed in shallow, stagnant water. Reduce the amount of standing water in or near your property by draining and/or removing it.
5) DEET - Use an insect repellent containing DEET (N, N-diethyl-m-toluamide).

As of August 25, seven horses had tested positive for the virus in Wyoming with four in Fremont County and one each in Campbell, Natrona and Park counties. In addition, five birds have tested positive with three in Campbell and one each in Park and Platte counties.

The “5 D’s” of preventing West Nile Virus are:
1) DAWN and 2) DUSK - Most mosquito species prefer to feed at dawn or dusk, so to reduce your chance of being bitten, you should avoid spending time outside during these times.
3) DRESS - Wear shoes, socks, long pants, and a long-sleeved shirt when spending time outdoors or when mosquitoes are most active. Clothing should be light-colored and made of tightly woven materials to keep mosquitoes away from the skin.
4) DRAIN - Mosquitos breed in shallow, stagnant water. Reduce the amount of standing water in or near your property by draining and/or removing it.
5) DEET - Use an insect repellent containing DEET (N, N-diethyl-m-toluamide). Products containing DEET should be used properly. When using DEET, be sure to read and follow the instructions on the product’s label. Avoid excessive use or over-application. In most circumstances, products with 10 to 35 percent DEET provide adequate protection for adults. Spray clothing with repellents containing permethrin or DEET because mosquitoes can bite through thin clothing. Permethrin should not be used on bare skin.
(The Centers for Disease Control and Prevention (CDC) has stated that another insect repellent, Picaridin (KBR 3023), is also highly effective. Two other scientific studies have also suggested that oil of lemon eucalyptus, a plant based repellent, is also effective and provides protection similar to those products containing low concentrations of DEET. While many new products have been shown to provide some protection against mosquito bites, DEET has been the most studied and reliable mosquito repellent for personal use. Product labels should be consulted to determine the length of time that protection can be expected from a product. More information about repellents and insecticides can be found on the National Pesticide Information Center’s website at http://npic.orst.edu/index.html or at 1-800-858-7378.)

Property owners can also start reducing mosquito breeding grounds. Property owners should go through this checklist several times during the spring through the early fall.
• Use smart landscaping to eliminate standing water that collects on your property.
• Repair failed septic tanks.
• Dispose of containers that collect water such as tin cans, ceramic pots, or plastic containers.
• Remove or discard old tires on your property - used tires are very common mosquito breeding sites.
• If you cannot dispose of old tires, drill holes in them to allow water to drain.
• For containers that must remain on your property such as bird baths, wading pools, or troughs, change the water at least once a week.
• Repair leaky water pipes and outdoor faucets.
• Ensure that your roof gutters are draining properly.
• Turn over plastic wading pools and wheelbarrows when not in use.
• Cover trash containers to keep water out.
• Aerate ornamental ponds or stock them with predatory fish.
• Clean and chlorinate outdoor swimming pools even when they are not in use.
• Keep drains, ditches, and culverts free of grass clippings, weeds, and trash so water will drain properly.
• Remove vegetation and debris from the edge of ornamental ponds.

More information about West Nile virus can be found on the Wyoming Department of Health’s “Bad Skeeter” website: www.badskeeter.org.

By following the "5 D's" people can eliminate breeding sites for mosquitoes and avoid getting bitten:

(1) DAWN AND (2) DUSK - When possible, avoid spending time outside at dawn and dusk.

(3) DRESS - Wear shoes, socks, long pants and a long-sleeved shirt when outdoors for long periods of time or when mosquitoes are most active. Clothing should be light colored and made of tightly woven materials to keep mosquitoes away from the skin.

(4) DRAIN - Reduce the amount of standing water in or near your property by draining and/or removing it. Mosquitoes may lay eggs in areas with standing water. See below for more information and tips on reducing the amount of standing water in or near your property.

To reduce standing water, consider the following:

- Repair failed septic systems.

- Dispose of tin cans, plastic containers, ceramic pots or similar water-holding containers.

- If possible, remove old or discarded tires on your property. Used tires have become the most common mosquito breading site in the country. If you cannot dispose of old tires, you can drill holes in them to allow standing water to drain.

- For containers that must remain on your property, such as bird baths and wading pools, change the water at least once per week.

- Cover trash containers to keep out rainwater.

- Repair leaky water pipes and outside faucets.

- Aerate ornamental pools or stock them with predatory fish.

- Clean and chlorinate swimming pools even if they are not being used.

- Keep drains, ditches, and culverts free of grass clippings, weeds and trash so water will drain properly.

- Remove all leaf debris.

- Drill holes in the bottoms of all recycling containers that are kept outdoors.

- Make sure roof gutters drain properly. Clean clogged gutters in the spring and fall to remove leaves or other debris that may clog the drains or gutters.

- Turn over plastic wading pools and wheelbarrows when not in use.

- Clean vegetation and debris from the edge of ponds.

- Drain water from pool covers.

- Use landscaping to eliminate standing water that collects on your property.

- Install or repair screens for windows and doors that stay open, so that mosquitoes cannot get indoors.

- Place mosquito netting over infant carriers when you are outdoors with infants.

(5) DEET - For additional protection from mosquitoes, use an insect repellent containing DEET (N,N-diethyl-m-toluamide). Spray clothing with repellents containing permethrin or DEET because mosquitoes may bite through thin clothing. Products containing DEET must be used properly. When Using DEET, be sure to Read and follow instructions on the label to avoid excessive use and over-application. In most circumstances products with 25 to 35 percent DEET provide adequate protection for adults.

WEST NILE VIRUS FACT SHEET

What is West Nile Virus?

West Nile virus (WNV) is a flavivirus that can cause human infection. Other flaviviruses include St. Louis encephalitis virus (SLEV) which is found in the United States, Japanese Encephalitis virus from South East Asia, and Murray Valley fever virus from Australia and New Guinea. WNV as well as other flaviviruses are also classified as arboviruses. Arboviruses belong to several families of viruses that usually infect birds and are transmitted from bird to bird by mosquitoes. Infected mosquitoes can then transmit the virus when biting humans and other mammals. Wyoming has three human diseases caused by arboviruses: West Nile virus infection, Saint Louis encephalitis, and Western Equine encephalitis.

WNV is historically found in Africa, the Middle East, and Central Europe. In 1999, WNV was first identified in the United States in New York City and has since spread to all 48 contiguous states. Hawaii and Alaska have not yet reported WNV activity. In 2004, 2,470 people became ill and 88 people died from WNV infection in the United States. However, less than 1 percent of the people infected with WNV become seriously ill. About 20% of the people infected develop flu-like symptoms and the majority of people never get sick.

Mosquitoes spread this virus after they feed on infected birds and then bite people, other birds or animals. WNV is not spread by routine person-to-person contact and there is no evidence that people can get the virus by routine handling of infected animals.

Surveillance for West Nile virus activity in Wyoming was initiated by the Wyoming Department of Health and the University of Wyoming State Veterinary Laboratory in 2001 and currently involves the reporting and testing of suspected human cases and dead birds and the testing of sick horses. Suspected human cases are tested in the Wyoming Department of Health's Public Health Laboratory or other regional laboratories and are reported to the Wyoming Department of Health for follow-up. The Wyoming Department of Health keeps track of human cases of WNV so that it can identify potential risk factors for illness.

WNV human infection may range from asymptomatic infection to mild infection (West Nile fever) to severe illness (West Nile neuroinvasive disease).West Nile virus human cases in Wyoming occur primarily in the late summer or early Fall, although the mosquito season in Wyoming is typically April through October. People with mild WNV infections may experience fever, headache, body aches, skin rash and swollen lymph glands. This is called West Nile fever. People with more severe infections may experience high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, and paralysis. This is called West Nile neuroinvasive disease, which may include encephalitis, meningitis, and a polio-like syndrome. If you have any of these symptoms, contact your health care provider. Please see your primary care physician for more details on human infection and testing.

How can I get West Nile virus infection?

The principal route of human infection is through the bite of an infected mosquito.

In 2002, additional routes became apparent; however, this represented a very small proportion of cases. These routes include receiving transplanted organs and blood transfusions, transplacental (mother to unborn child), possibly through breast-feeding, and through exposure to West Nile infected products in the laboratory.

Who is most at risk?

Anyone can get the virus. People who are more likely to be bitten by mosquitoes (i.e. people who spend a lot of time outdoors) are at an increased risk of developing infection. People over 50 years of age have the highest risk of developing a severe illness because as we age, our bodies have a harder time fighting off disease. People with compromised immune systems (i.e. individuals with HIV/AIDS, cancer patients, organ transplant recipients) are also at increased risk of severe disease.

What are the symptoms?

People with mild infections may experience fever, headache, body aches, skin rash and swollen lymph glands. This is called West Nile fever.

People with more severe infections may experience high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, and paralysis. This is called West Nile neuroinvasive disease. If you have any of these symptoms, contact your health care provider.

Are there long-term consequences?

While most infections are usually mild, West Nile neuroinvasive disease can result in death or serious brain damage. The CDC notes that neurological effects may be permanent. Some improvements may be seen over time.

Is there treatment or a vaccine?

There is no specific human treatment or vaccine for West Nile virus infection. While most people fully recover from the viral infection, in some severe cases hospitalization may be needed.

About West Nile Neuroinvasive Disease

The majority of people who get infected with the virus have no illness, or at most, have a relatively mild flu-like illness with fever, headache and fatigue. Rarely will the virus multiply in the central nervous system and cause neuroinvasive disease (infection of the brain and/or spinal cord). Some people who develop West Nile neuroinvasive disease (encephalitis, meningitis, or poliomyelitis-like illness) have serious long-term health problems (up to two-thirds in some studies) and some people never fully recover. Encephalitis and meningitis are illnesses that affect the brain and the lining of the brain. These illnesses are caused by a virus which attacks and destroys some nerve cells and causes brain inflammation and swelling.

How to Protect Yourself

Although mosquitoes are most active at dusk or dawn, some bite during the day. All mosquitoes will bite if you enter an area where they are resting, such as high grass or heavy underbrush. While it is not usually necessary to limit outdoor activity (unless there is evidence of mosquito-borne disease in the area), you can and should reduce your risk of being bitten by mosquitoes.

Common sense steps you can take to minimize the probability of infection include remembering the 5 D's of West Nile Virus:

(1) DAWN AND (2) DUSK - When possible, avoid spending time outside at dawn and dusk.

You can protect your family from biting mosquitoes by reducing the amount of standing water available for mosquito breeding in or near your property. To reduce standing water, consider the following:

- Repair failed septic systems.

- Dispose of tin cans, plastic containers, ceramic pots or similar water-holding containers.

- For containers that must remain on your property, such as bird baths and wading pools, change the water at least once per week.

- Cover trash containers to keep out rainwater.

- Repair leaky water pipes and outside faucets.

- Aerate ornamental pools or stock them with predatory fish.

- Clean and chlorinate swimming pools even if they are not being used.

- Keep drains, ditches, and culverts free of grass clippings, weeds and trash so water will drain properly.

- Remove all leaf debris.

- Drill holes in the bottoms of all recycling containers that are kept outdoors.

- Make sure roof gutters drain properly. Clean clogged gutters in the spring and fall to remove leaves or other debris that may clog the drains or gutters.

- Turn over plastic wading pools and wheelbarrows when not in use.

- Clean vegetation and debris from the edge of ponds.

- Drain water from pool covers.

- Use landscaping to eliminate standing water that collects on your property.

If you know of specific mosquito control problems or problem areas, call your local city or county public works director, City Hall, or the Board of Supervisors.

(5) DEET - For additional protection from mosquitoes, use an effective insect repellent containing DEET or Picaridin. Permethrin may be used on clothing, shoes, bed nets, and camping gear. However, permethrin is not recommended for use on bare skin. Spray clothing with repellents because mosquitoes may bite through thin clothing. When using any insect repellent or insecticide, be sure to read and follow instructions on the label to avoid excessive use and over-application. In most circumstances, products with 25 to 35 percent DEET provide adequate protection for adults.

- Apply repellents only to exposed skin and/or clothing (as directed on product label). Do not use repellents under clothing.

- Never use repellents over cuts, wounds, or irritated skin.

- Do not apply to eyes or mouth, and apply sparingly around ears. When using sprays, do not spray directly on face - spray on hands first and then apply to face.

- Do not allow children to handle the product. When using on children, apply to your own hands first and then put on child. You may not want to apply to childrens hands.

- Use just enough repellent to cover exposed skin and/or clothing. Heavy application and saturation are generally unnecessary for effectiveness. If biting insects do not respond to a thin film of repellent, then apply a bit more.

- After returning indoors, wash treated skin with soap and water or bathe. This is particularly important when repellents are used repeatedly in a day or on consecutive days. Also wash treated clothing before wearing it again. (This precaution may vary with repellents - check the product label).

- If you or your child gets a rash or other bad reaction from an insect repellent, stop using the repellent, was the repellent off with mild soap and water, and call a local poison control center for further guidance. If you go to a doctor because of the repellent, take the repellent with you to show your doctor.

More information about insect repellents and insecticides can be found on the National Pesticide Information Centers website at http://npic.orst.edu/index.html or at 1-800-858-7378.

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Why do we Monitor Dead Birds?

Birds and horses typically become infected with West Nile virus (WNV) before humans, so dead birds and sick and dead horses are an indicator of WNV activity. We use animal surveillance to map the distribution and prevalence of WNV so that health and mosquito control officials are aware of its presence and can take whatever measures are available to mitigate the impact of WNV on human and equine populations. The idea is to identify the virus before humans are affected so that public education and mosquito control can reduce the impact.

Dead Bird Reporting

Report only dead crows, ravens, jays, and magpies.

If you find a dead bird on your property, DO NOT SEND it to state or local health agencies. Call the West Nile toll-free number at 1-877-WYO-BITE for instructions. You will be asked to provide the following information: name, phone number, bird species, number dead, address where bird was found, and approximate date of death.

If the bird(s) are suitable for testing you will be advised on how to handle and submit the carcasses.

If Asked to Send a Dead Bird

Handle dead bird with gloves or put a plastic bag over your hand to pick up the carcass. Then double-bag the bird and add an ice pack if available. Place the bagged bird in a cool place but not in your refrigerator or freezer.

WNV is transmitted primarily through the bite of an infected mosquito. Persons cannot become infected through routine contact with an infected bird, horse, or human.

You will be advised by the person you speak with at the toll-free number on how the carcass(es) will be transported to the laboratory for testing.

Not every bird that is submitted will be tested. Reasons include bird is too decomposed, excessive birds have already been submitted from the area, bird is wrong species, etc.
Results

Results are usually available within 2 weeks. Persons will be notified ONLY IF the bird is positive.

The Wyoming Department of Health will continue to test jays, magpies, crows, and ravens from the state between May 1 and October 31, 2005.

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