West Nile Virus and How You Can Help

West Nile Virus (WNV):  West Nile Virus is spread to humans by the bite of an infected mosquito.  When a mosquito bites a bird that carries the virus, the mosquito is infected, it may transmit the virus to people when it bites them.

Symptoms of West Nile Virus:  Most humans infected with WNV have no symptoms.  A small percentage of individuals infected, develop mild symptoms that include fever, headaches, body aches, swollen lymph glands, and a body rash.

Encephalitis can develop, but is rare in less than 1% of infected people, with severe symptoms that include headache, high fever, neck stiffness, disorientation, tremors, convulsions, paralysis, and coma.

If you experience these symptoms, contact a physician or hospital immediately.

Occasionally, death can occur.  The elderly are most at risk of death due to encephalitis.

Mosquito Fact Sheet:  All mosquitoes need water for laying and hatching of eggs and early life development.  Some mosquitoes lay eggs in standing water, where they hatch within a couple of days.  Other mosquitoes lay eggs in old tires, tin cans, or other water holding containers, where they may remain unhatched for weeks or months until they are covered with water.

Mosquitoes most commonly breed in wooded, swampy low areas, marshes, retention basins, detention basins, construction sites, parks, recreation areas, catch basins and storm drains.  Only female mosquitoes require blood meal and bite animals and humans.  Male mosquitoes do not bite, but feed on the nectar of flowers.

The mosquito goes through four separate and distinct stages of its life cycle:  egg, larva, pupa, and adult.

WNV Facts:  The continued expansion of WNV in the U.S. indicates that it is permanently established in the Western Hemisphere.

• Infection occurs primarily in the late summer or early fall but in southern climates, WNV can be transmitted year round.
• Much less than 1% of mosquitoes in an infection area are actually carrying the virus.  Less than 1% of people who are bitten and become infected will become severely ill.
• Fatality rates of WNV range from 3% to 15% of the total 1% who become severely ill and are highest among the elderly and immuno-compromised individuals (such as cancer and AIDS patients).
• WNV cannot be transmitted directly from animal to person, from animal to animal, or form person to person.
• People over 50 years of age are at higher risk.
• Symptoms will occur 3-15 days after infection.
• There is no vaccine available for humans.
• Proper cooking kills the WNV.  Therefore, there is no danger associated with eating thoroughly cooked wild game that might be infected.

WNV and Horses:  Horses can develop encephalitis from WNV infections.  The majority of horses infected recover, but some infections have resulted in death.  Signs of WNV infection in horses include listlessness, incoordination, weakness, recumbency, and muscle tremors.  WNV cannot be transmitted to a person caring for a horse infected with WNV.

There is no documented evidence that WNV is transmitted between horses in neighboring stalls.  However, horses with suspected WNV should be isolated from mosquitoes, if possible.

A killed WNV vaccine for horses is available but its effectiveness is not yet known.  You can protect your horses from mosquitoes by providing them with screened shelters.  Using insect repellents and keeping horses indoors at night may reduce risk of infection.

The City of Marysville's intent is to protect the health, safety and welfare of the citizens of Marysville.  This program includes management methods which are widely accepted to be integral components of an integrated approach to mosquito management.  These methods include:

• Providing Public Education about mosquito borne diseases and prevention methods.

• Identification of mosquito breeding sites on public property and eliminating these sites.

• Larvaciding public areas that are providing breeding conditions for mosquitoes, and thereby interrupting the life cycle by eliminating mosquito larvae.

• Monitoring the mosquito populations both in numbers and species in order to detect disease carrying mosquitoes, and to provide data to be used as a basis for management decisions.  MONITORING IS CURRENTLY BEING DONE BY THE UNION COUNTY HEALTH DEPARTMENT.  Call 642-2053 for more information.

• Adulticiding mosquitoes with fogging chemicals when disease mosquitoes are present or actual human cases are idendtified.

Together We Can Control Mosquitoes and Enjoy the Great Outdoors!

1. To abate existing mosquito breeding areas in public areas.
2. To prevent new breeding sites in public areas so you can fully use and enjoy your backyard and other municipal recreation facilities.
3. To protect public health and comfort.

Your responsibility as a property owner:

1. Dispose of old tires, tin cans, buckets, drums, bottles, or any water holding containers.
2. Fill in or drain any low places in yard.
3. Keep drains, ditches and culverts clean of weeds and trash so water will drain properly.
4. Cover trash containers to keep out rain water.
5. Repair leaky pipes and outside faucets.
6. Empty plastic wading pool at least once a week and store it indoors when not in use.
7. Make sure your backyard pool is properly cared for while on vacation.
8. Fill tree rot holes and hollow stumps that hold water and hollow stumps.
9. Keep grass cut short and shrubs well trimmed around the house so adult mosquitoes will not hide there.
10. Change water in bird baths and plant pots or drip trays at least once a week.

Personal Prevention/Protection Measures

• Avoid outdoor activities between dusk and dawn when mosquitoes are likely to be biting.
• If you must be outdoors when mosquitoes are active, cover up by wearing shoes, socks, long pants, and long-sleeves.  Light colors are less attractive to mosquitoes.
• Use mosquito repellent containing DEET according to label directions:  Adults should use repellent with not more than 30% DEET; for children, 10% or less.
• Use colognes and perfumes sparingly as these may attract mosquitoes.
• Make sure window and door screens are "bug tight".
• Use the proper type of light outside:  incandescent lights attract mosquitoes, whereas fluorescent lights neither attract nor repel mosquitoes.

If you have any questions or concerns, please call (937) 642-7557, Monday-Friday 8am-3:30pm.