Disease Control - West Nile

West Nile Virus 2003 Information
In the fall of 1999, West Nile virus (WNV), a mosquito borne infection that can cause encephalitis, was first found in New York State. The virus is transmitted by certain mosquitoes that tend to breed in urban areas. These mosquitoes feed on infected birds and become carriers of the virus in their salivary glands. When an infected mosquito bites a human, bird, or other animal, the virus is then transmitted where it may multiply and cause illness. In 2002, WNV spread throughout the United States and it is likely to recur on a seasonal basis.
The chance that any one person is going to become ill from a bite is low. Most people who become infected with West Nile virus will have either no symptoms or only mild ones, including: fever, headache, and body aches. Symptoms generally appear 5 to 15 days after exposure. There is no specific treatment for viral infections, other than to treat the symptoms and provide supportive care. Those who may be susceptible to encephalitis are infants, the elderly and persons with impaired immune systems. Fortunately, in areas where WNV has been identified, the risk of contracting the virus from a mosquito bite is extremely low.
The Rensselaer County Department of Health has developed a WNV Control Plan, based upon statewide recommendations, that emphasizes education and non-pesticide methods of eliminating mosquito breeding sites. Following State guidelines, our Department is engaged in active county-wide surveillance to identify the larvae and adult forms of the Culex pipiens mosquito that is most closely associated with WNV. The Department will also coordinate the use of the least toxic larvicides to reduce adult mosquito populations in urban areas.

Mosquito Facts:
There are about 65 different species of mosquitoes in New York State. While most do not transmit West Nile virus, several mosquito species have been associated with the West Nile virus.

The Culex pipiens mosquito is the most common species associated with West Nile virus. They usually fly no more than 300 feet from their breeding site. Some mosquitoes, such as Culex pipiens, are most active between dusk and dawn, when air is calm. However, they may be present at any time of day.

Mosquitoes can develop in any standing water that lasts more than 4 days. To reduce the mosquito population around your home, reduce or eliminate all standing water and debris.

Click here for additional information about Rensselaer County’s larviciding program.

Fight the Bite

1. WHAT IS WEST NILE VIRUS?
West Nile virus (WNV) is a mosquito-borne infection that can cause serious illness, and in some cases, death. Although a person’ s chances of getting sick are small, there are some simple steps you can take to reduce your risk of being bitten by mosquitoes.

2. WHAT ARE THE SYMPTOMS OF WEST NILE VIRUS?
Most people who are infected with the West Nile virus will not have any type of illness. It is estimated that 20% of the people who become infected will develop West Nile fever: mild symptoms, including fever, headache, and body aches, occasionally with a skin rash and swollen lymph glands. In many individuals, these symptoms are so mild that they go unnoticed or undetected.
The symptoms of severe infection (West Nile encephalitis or meningitis) include headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness and paralysis. It is estimated that one in 150 persons infected with the West Nile virus will develop the more severe form of the disease. Usually, symptoms occur from three to14 days after exposure. There is no specifc treatment for viral infections, other than to treat the symptoms and provide supportive care.

3. WHO IS AT RISK FOR GETTING WEST NILE VIRUS?
All residents of areas where virus activity has been identifed are at risk of getting West Nile virus; persons over 50 years of age are at the highest risk for severe disease.

4. HOW IS WEST NILE VIRUS TRANSMITTED?
WNV is primarily transmitted through the bite of an infected mosquito. Over 30 species of mosquitoes have been infected nationwide. In 2002, West Nile Virus was documented to be transmitted by blood transfusion or organ transplantation in a small number of cases. In addition, one case of transmission through breast-feeding and one case of transplacental (mother to child) WNV transmission were documented. The U.S. Centers for Disease Control is working with the Food and Drug Administration, blood collection agencies, and state and local health departments to investigate possible cases of West Nile Virus transmission through blood transfusion and organ transplantation.
These transfusion and transplant–related cases make up a small percentage of those infected with WNV. Although persons needing blood transfusions or organ transplants should be aware of the risk of West Nile Virus infection, the benefits of receiving needed transfusions or transplants outweigh the potential risk for WNV infection.

5. DO ALL MOSQUITOES TRANSMIT DISEASE?
No. Most mosquitoes do not transmit disease. While there are about 70 different species of mosquitoes in New York State, only certain species have been associated with West Nile virus.

6. WHERE DO MOSQUITOES LIVE AND BREED?
Mosquitoes lay their eggs in moist areas, such as standing water. The eggs become larvae that remain in the water until the adults mature and fly off. Weeds, tall grass and shrubbery provide an outdoor home for adult mosquitoes. They can also enter houses through unscreened windows and doors, or broken screens. Many mosquitoes will breed in containers that hold water, such as flowerpots or discarded tires.

7. WHEN ARE MOSQUITOES MOST ACTIVE?
Some mosquitoes are active between dusk and dawn, when the air is calm. However, others will feed at any time of day. Mosquitoes prefer a warm, moist environment. They are active from early summer until late fall in New York State. In southern states that have a warm year-round climate, mosquitoes that transmit West Nile virus are active year round. New Yorkers should take measures to protect themselves from mosquito bites when traveling to these states.

8. WHICH BIRDS CAN CARRY WEST NILE VIRUS?
In New York State, most West Nile virus-positive birds have been American crows. The State Health Department is using dead crow sightings to track West Nile virus, so it’s important to report any dead crows to your local health department or to the toll-free dead bird hotline, 1-866-537-BIRD (2473). Not all dead crows need to be tested for West Nile virus. If the bird is not going to be collected, you may dispose of it. Wear thick gloves, double bag the bird, and place it in the trash. There is no evidence that birds can transmit West Nile virus directly to people. However, barehanded contact with dead animals should always be avoided.

9. CAN MY PET BE INFECTED?
West Nile virus has been confrmed in some domestic animals, including pet birds, dogs and cats. Horses can become seriously ill, if infected. There is no evidence that West Nile virus is spread directly from animals to humans.

10. HOW CAN I PROTECT MYSELF AND MY FAMILY?
To reduce the mosquito population around your home and property, reduce or eliminate all standing water:

• Dispose of tin cans, plastic containers, ceramic pots or similar water-holding containers.
• Dispose of used tires. Used tires are a signifcant mosquito breeding site. Call your local landfll or Department of Public Works to fnd out how to dispose of them properly.
• 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.
• Remove leaf debris from yards and gardens.
• Turn over wading pools and wheelbarrows when not in use.
• Change the water in birdbaths twice weekly.
• Clean vegetation and debris from edges of ponds.
• Clean and chlorinate swimming pools, outdoor saunas and hot tubs.
• Drain water from pool covers.
• Use landscaping to eliminate standing water that collects on your property.

11. SHOULD WE STAY INDOORS?
It is not necessary to limit outdoor activities. However, you can and should try to reduce your risk of being bitten by mosquitoes. In addition to reducing standing water in your yard, make sure all windows and doors have screens, and that all screens are in good repair. If West Nile virus is found in your area:

• Wear shoes and socks, long pants and a long-sleeved shirt when outdoors for long periods of time, or when mosquitoes are most active.
• Consider the use of mosquito repellent, according to directions, when it is necessary to be outdoors when mosquitoes are biting.

12. WHAT IS BEING DONE IN MY COMMUNITY TO CONTROL MOSQUITOES?
The New York State Department of Health, along with other state agencies, local health departments, colleges and environmental groups, has prepared a plan to address issues related to West Nile virus in the Empire State and has devised a preventive strategy to minimize the impact. Local communities are implementing various control measures based on geographic location and level of risk. For more information regarding activities in your specific area, contact Rensselaer County Department of Health at 270-2655, or visit the New York State Department of Health’s Web site at www.health.state.ny.us.

Tick and Insect Repellents:
Deciding on Their Use
According to the American Academy of Pediatrics, repellents used on children should contain no more than 10 percent DEET.

Repellents can be effective at reducing bites from ticks and insects that can transmit disease. But their use is not without risk of health effects, especially if repellents are applied in large amounts or improperly. Information in this fact sheet will help decide when and if a repellent is right for you.
ABOUT DEET AND PERMETHRIN PRODUCTS

DEET (the label may say N, N-diethyl-m-toluamide) comes in many different concentrations, with percentages as low as five percent or as high as 100 percent. In general, the higher the concentration the higher the protection, but the risk of negative health effects goes up, too. Use the lowest concentration that you think will provide the protection you need.

DEET products have been widely used for many years, but have occasionally been associated with health effects. Skin reactions (particularly at concentrations of 50 percent and above) and eye irritation are the most frequently reported health problems. There have been some reports of central nervous system problems, more frequently reported in children than adults, ranging from slurred speech and confusion to seizures and coma.

Products containing permethrin are for use on clothing only, not on skin. Permethrin kills ticks and insects that come in contact with treated clothes. Permethrin products can cause eye irritation, particularly if label directions have not been followed. Animal studies indicate that permethrin may have some cancer-causing potential. Permethrin is effective for two weeks or more if the clothing is not washed.

Keep treated clothing in a plastic bag when not in use. If you decide to use any kind of repellent, carefully read and follow all label directions before each use. On the labels, you will find important information about how to apply the repellent, whether it can be applied to skin and/or clothing, special instructions for children, hazards to humans, physical or chemical hazards and first aid.

CHILDREN, PREGNANT WOMEN AND REPELLENTS

• Children may be at greater risk for adverse reactions to repellents, in part, because their exposure may be greater.
• Keep repellents out of the reach of children.
• Do not allow children to apply repellents to themselves.
• Use only small amounts of repellent on children.
• Do not apply repellents to the hands of young children because this may result in accidental eye contact or ingestion.
• Try to reduce the use of repellents by dressing children in long sleeves and long pants tucked into boots or socks whenever possible. Use netting over strollers, playpens, etc.
• As with chemical exposures in general, pregnant women should take care to avoid exposures to repellents when practical, as the fetus may be vulnerable.

CONSIDERATIONS
When thinking about using a repellent, consider a combination of things, including where you are, how long you will be outside and how bad the bugs are, and if those bugs carry disease. Every situation is different. Use the following questions to make a "profile" that fits your situation – this may help you decide if you want to use a repellent, and if so, which kind.

What type of pest are you concerned about?
Ticks may be more difficult to repel than mosquitoes. Repellents provide some protection against ticks, as does wearing light-colored, long-sleeved shirts and long pants, with bottoms tucked into socks and boots.

When will you be outside? Where will you be?
Some pests are more active at certain times - for example, some mosquitoes are most active between dusk and dawn. Ticks may be active at any time of day. Some places are more likely to have higher activity, too - mosquitoes generally live in areas with brush and trees. Ticks prefer areas with tall grass, brush and trees.

How long will you be outside?
Are you doing some gardening, going on a hike, camping for a week? The longer you are out, the more protection you may need. Some people exposed to high levels of ticks and mosquitoes for long periods of time use a two-part approach. With this approach, about 33 percent DEET in a controlled release formula is applied on exposed skin, and clothing is treated with permethrin. If, on the other hand, you are going to do some yard work or have a picnic during mid-day when mosquito activity is low and you decide to use an insect repellent, DEET concentrations as low as five percent may provide sufficient protection from mosquito bites for up to about four hours.

Remember: If you decide to use a repellent, use only what and how much you need for your situation!

If you have questions about mosquitoes, West Nile virus, encephalitis, or use of insect repellents, contact Renselaer County Department of Health at 270-2655 or call the New York State Health Department's Environmental Health INFOLINE at 1-800-458-1158. To report dead birds, particularly dead crows, again contact the Rensselaer County Department of Health at 270-2655 or call toll free at 1-866-537-BIRD.

Visit the New York State Department of Health West Nile Virus Web-site at: http://www.health.state.ny.us/nysdoh/westnile/index.htm

Report a Dead Bird
To assist us in our surveillance activities, Rensselaer County residents are requested to report the findings of dead birds, especially crows, that are thought to have died within the last 24 hours, to our Environmental Division at (518) 270-2674.

You can also report dead birds to the USDA Wildlife Services 24 hour toll-free hotline at 1-866-537-BIRD (2473).

For questions regarding identification of mosquito breeding areas and the use of larvicides, please call our Environmental Division at (518) 270-2674.

Reporting Dead Birds
What is West Nile virus?
West Nile virus (WNV) is a mosquito-borne infection that can cause encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord).

What role do birds play in the transmission of West Nile virus to people?
Mosquitoes become infected with West Nile virus by biting infected birds. Humans become infected when they are bitten by an infected mosquito.

Why is it important to report dead birds?
Dead birds may provide an early indication of the appearance of West Nile virus in an area and may help to forecast the chances of people becoming infected.

Where is West Nile virus found?
The first humans and birds with West Nile virus were found in downstate New York in 1999. Since then, the virus has spread throughout New York State and across the continental United States.

What measures are now being taken to protect the public from West Nile virus?
The New York State Department of Health, in partnership with counties, New York City, other state and federal agencies, universities, and private organizations, has developed a comprehensive plan to reduce the risk of West Nile virus. The plan includes testing people, mosquitoes, dead birds, rabies-negative dead mammals and ill animals for the virus. Testing is available year-round, but is increased during mosquito season (spring through fall).

How should I report any dead birds that I see?
Contact your county health department at 270-2674 or the toll-free hotline, 1-866-537-BIRD (2473), during regular business hours. Because crows are an especially good indicator of West Nile virus, it is critical to report all dead crows.

What information do I need to give when I report dead birds?
You should report the type of bird (if you know it), its location (including town, street, nearest cross street and ZIP code), and the date you saw it. You will be asked to leave your name and phone number so that the county can follow up for bird collection.

What should I do with the dead bird until it is picked up for testing?
Each county health department has its own procedures for picking up dead birds for West Nile virus testing, and not all birds can be tested. If the bird cannot be reported or picked up right away, use a shovel or wear gloves to place it in a bag, and then put it in a refrigerator or ice chest that is not used for food. If that’s not possible, place plastic bags of ice over the dead bird and cover it with a bucket until health officials arrive.

What should I do if I'm told the dead bird does not require testing?
If testing is not required, use a shovel or wear gloves to double-bag the bird, and dispose of it in the trash. Or bury it at least three feet deep, away from a stream or other water source.

Do I risk getting West Nile virus by handling a dead bird?
There is no evidence that West Nile virus is spread directly from dead birds to humans. However, barehanded contact with dead animals should always be avoided. Use a shovel or wear gloves when handling a dead animal.

How long does it take to test a dead bird for West Nile virus?
The New York State Health Department tests birds according to geographical priority, not date received; therefore, it is not possible to provide timeframes.

Will I receive the test results of the bird(s) that I submit for testing?
Due to the large number of test specimens, county health departments are not always able to provide specific test results to individuals submitting birds.

How will test results be used?
Test results are used to guide prevention and control efforts. Summaries are available on the Department’ s Web site: http://www.health.state.ny.us/nysdoh/westnile/index

If I see a lot of crows roosting, should I be concerned about West Nile virus?
Crow roosts are natural phenomena in New York State. A large group of healthy, live crows is good news. Because crows are so sensitive to the disease, it probably indicates that West Nile virus is not a high risk in the area at that time. However, dead crows may indicate the presence of the virus and should be reported as soon as possible.

Are pet birds or poultry at risk for West Nile virus?
Pet birds and poultry can become infected with West Nile virus.

Can an infected dead bird pose a risk to my pet?
Pets occasionally get West Nile virus from mosquito bites. Horses are more susceptible to serious illness from WNV than are dogs and cats. Natural infection of a pet by contacting or eating an infected dead bird has not been documented.

TO REPORT A DEAD BIRD, CALL RENSSELAER COUNTY HEALTH DEPARTMENT at 270-2674 OR CALL: TOLL-FREE 1-866-537-BIRD (2473).

New York State:

• Department of Health - West Nile Virus Information for Providers,
  Information About Pesticides and Insect Repellents, Educational Materials, Related Links

If you have questions about mosquitoes, West Nile virus, encephalitis, or use of insect repellents, contact your local health department or call the New York State Health Department's Environmental Health INFOLINE at 1-800-458-1158. To report dead birds, particularly dead crows, contact your local county health department or call toll free at 1-866-537-BIRD.

For more information please check our department home page or search our site.