PHOTO CAPTION: A culex mosquito bites a person's finger. Several different species of culex mosquitoes can carry the West Nile Virus, but only the female bite people, birds and other animals. The mosquitoes contract the virus by biting birds that are infected. Normally, people cannot contract the virus from birds, or transmit it to other oeople should they become infected.
August 22, 2013
By Ben Sherman, Fort Sill Cannoneer
FORT SILL, Okla. -- The West Nile Virus has returned to the Fort Sill community. On Aug. 13 the Preventive Medicine department at Reynolds Army Community Hospital reported positive counts for mosquitoes infected with West Nile Virus were discovered in four of the six traps placed around post. This report was released the same week a teenage girl in Oklahoma County, near Oklahoma City, tested positive for the West Nile virus. Many people in the Fort Sill community are concerned about becoming infected with the virus.
"West Nile Virus (WNV) is a blood-borne disease transmitted to humans by the bite of infected culex mosquitoes. Although most people who are infected with WNV will feel fine, some may experience flu-like symptoms," said Maj. Michael Superior, Chief of Preventive Medicine at Reynolds Army Community Hospital. "Fewer than 1 percent of people who are infected may become ill. The elderly are most at risk for developing a severe neurological condition called encephalitis. Since this disease is not transmitted person-to-person, it is not necessary to isolate or quarantine individuals."
In 2012, the United States set a record for the number of reported cases of WNV. Fort Sill and the surrounding area of Southwest Oklahoma were largely spared from the mosquito problem because of the prolonged drought in the region. But now that this area has had several weeks of steady rainfall, the mosquitoes have returned. Not all mosquitoes on or near Fort Sill are the type which carries the WNV. As of this time there have not been any human cases of the virus on Fort Sill or in Southwest Oklahoma. The greatest risk time for exposure to WNV infected mosquitoes in Oklahoma is from July through October.
Birds carry the West Nile Virus, which mosquitoes bite and become infected. Some of the common birds that carry this virus are bluebirds, crows and robins. Even though those birds are carriers they cannot transmit the virus to humans except in extremely rare cases. If you find a dead bird on post, do not pick it up, but contact Preventive Medicine at the number listed below.
Jonathan Williams is a pest control supervisor for Professional Contract Services, Inc., a contractor working with the Fort Sill Directorate of Public Works. He explained how the process of mosquito abatement works here.
"Preventive medicine puts out traps to catch the mosquitoes. They collect and count the female mosquitoes, which are the ones that bite. If there are more than 25 female mosquitoes in a trap, then they contact us to begin spraying or fogging," he said. "During the drought, the mosquito count was very low, around 10 to 15 mosquitoes per trap and sometimes none. This year we have caught as many as 455 in the six traps around post. Right now we're averaging between 30 and 100 per trap, which is a lot."
PCSI Pest Control and DPW are working closely with Preventive Medicine to deal with the mosquito problem. PCSI has deployed larvicide briquettes in storm drains and low or standing water sources they cannot drain around post to stop mosquitoes from breeding.
"They slowly dissolve and puts a film on top of the water so that the mosquito larvae cannot hatch. We've put out around 3,700 briquettes so far. We usually average 1,500 per year and I have already had to reorder this year because of the mosquitoes, trying to control them," Williams said. "The Martha Songbird park area was one that tested hot for West Nile mosquitoes last week. We've already put briquettes in those wooded areas, because those are areas where water stands after it rains." Other areas in addition to Martha Songbird park that have shown positive counts of infected mosquitoes are: the obstacle course next to Bldg. 5983, the pond next to Bldg. 2440 and the area surrounding Rinehart Fitness Center. If personnel are jogging during fogging times in those areas, pest control cannot fog.
PCSI began fogging areas on the south side of Sheridan Road in the 6000 area (Key Gate-East at I-44) Aug. 19 and will continue to fog different areas on post for three weeks or until Preventive Medicine can confirm that infected mosquitoes are no longer showing up in their traps. Other areas will be scheduled for fogging once the garrison has coordinated PT schedules with the fogging efforts. Fogging will be conducted between 5:30-7 a.m. each day in the following areas on post:
Mondays South side of Sheridan Road in the 6000 area.
Tuesdays From Fort Sill Blvd. west to Pitman Street, and from Mow-Way Road north to Ringgold.
Wednesdays Martha Songbird Park area, from Bateman to Condon Road and Macomb to Upton Road.
Thursdays North side of Sheridan Road in the 6000 area.
Fridays South of Minor Road to Wilson Road and Babcock east to Sheridan Road.
Fort Sill officials strongly encourage Soldiers and civilians to take preventive measures on their own when outdoors in the Lawton-Fort Sill area. Protect yourself by remembering the 4 Ds:
1. DEET: Use only insect repellents that contain at least 30 percent DEET.
2. Dusk to dawn: Stay indoors at dusk and dawn when mosquitoes are most active.
3. Dress: Wear long-sleeves and long pants when outdoors; spray clothing with repellent.
4. Drain: drain or cover all sources of standing water to reduce mosquito-breeding sites.
Repellents with DEET can be used on children as young as 2 months old, according to the American Academy of Pediatrics but if you have questions or concerns contact your primary care provider.
"Parents should spray their children with at least 30 percent DEET repellents if the kids are out at the bus stops early in the morning, when mosquitoes are the worst. Mosquitoes can be bad at dusk also, but the majority will come out in the morning," Williams said.
From a health standpoint, WNV can be a serious illness for some segments of the community, particularly those over 50 years of age and young children. When someone has been infected with WNV they will typically show the following symptoms:
No symptoms: Approximately 80 percent of people who are infected with WNV will show no symptoms.
Mild symptoms: Up to 20 percent of the people who become infected develop symptoms such as fever, headache, and body ache.
Serious symptoms: About one in 150 people infected with WNV will develop severe neurological illnesses, which can include high fever, headache, neck stiffness, disorientation, muscle weakness, vision loss, numbness, paralysis and coma.
There is no vaccine or specific treatment for WNV infection. In cases with milder symptoms, people experience symptoms such as fever and aches that pass on their own. In more severe cases, people usually need to go to the hospital where they can receive supportive therapy.
"It is important to reassure everyone that existing preventive measures are effective, both on the population level through fogging to eradicate mosquitoes, and on the personal level through wearing loose, long-sleeved clothing, applying repellent containing DEET to exposed skin and avoiding activities that take them outside during early morning and evening hours," said Superior.
Additional information about West Nile Virus can be found at U.S. Army Public Health Command (www.phc.amedd.army.mil), the Oklahoma State Department of Health's WNV website (http://go.
usa.gov/wpz) or by calling Preventive Medicine at Reynolds Army Community Hospital at 580-422-0160.