By Ben Sherman, Fort Sill CannoneerAugust 23, 2012
FORT SILL, Okla.-- The West Nile virus has made a comeback in the United States this year with the biggest surge in cases since 2004.
There have been 1,118 cases reported across the country, with at least 41 deaths, according to the Centers for Disease Control in Atlanta. Texas has had about half of those cases. Oklahoma ranks fourth with 68 cases and three deaths as of Aug. 22.
So far there have been no cases reported in Southwest Oklahoma, but that doesn't mean officials at Fort Sill are not looking out for potential problems.
"People are interested in West Nile virus because of the stories on television and in the papers about what's going on in Dallas, with the degree of cases there and subsequent public health emergency declaration," said Maj. Nathan Teague, Reynolds Army Community Hospital Preventive Medicine chief. "We at Public Health remain vigilant and cautious, but we don't want to alarm people."
West Nile Virus is transmitted from infected mosquitoes which bite people. The mosquitoes get the disease from biting infected birds. The infected birds are the primary way in which the disease spreads across the country. Once mosquitoes are infected they lay their eggs in standing water or wet areas. When the larvae hatch, they develop into mosquitoes and bite people.
Teague went on to say although our area could benefit from rain in some respects, the dry summer may be limiting West Nile here by making it inhospitable for mosquitoes.
"We do badly need rain right now but a lot could cause problems," he said.
The Fort Sill Environmental Health Department is responsible for monitoring West Nile virus in mosquitoes by deploying mosquito traps at various places around post.
"We do the entomology program at Reynolds Army Community Hospital that deals with the mosquitoes, ticks and other insects," said Sgt. Brendan Ford, Environmental Health NCOIC. "We normally trap from about spring to all the way until it gets cold. Mosquitoes like cool, damp areas, along tree lines and especially near lakes and bodies of water. That's why we don't like to see standing water, because it can be a breeding ground for mosquitoes."
"We usually put out traps twice a week this time of the year. We start on a Tuesday and put traps out that afternoon and will trap overnight. We check them in the morning of the next day and that's when we have to change batteries and the cups that collect the mosquitoes." Ford said. "We really haven't had any mosquitoes recently. "
Ford explained that mosquitoes which are medically important with regard to West Nile are the culex mosquitoes, and females are the ones who bite and transmit the disease.
"Those are the ones we are really looking for. When we do get some we send the female mosquitoes to Public Health Command in San Antonio, Texas," Ford added.
The most important action that people can take to guard against mosquitoes is eliminating all sources of standing water. Mosquitoes lay their eggs in standing water, such as ponds, puddles, flower pots and other containers that have water.
"Get rid of standing water to reduce or eliminate the breeding grounds for mosquitoes," Teague stated. "Eliminate any container that could hold standing water from your property, such as kid's swimming pools that aren't being used. Old tires should be disposed of and planters should not have standing water in them. Also empty and refill water bowls for pets daily," he said.
Teague went on to list other precautions that people can take to minimize the chances of being bitten, such as wearing insect repellent when outside at dusk or dawn when mosquitoes are most active, along with wearing long sleeves and long pants when outside and avoiding areas near water or wetlands.
The CDC recommends when people go outside they should use mosquito repellents that contain at least 30 percent DEET. Repellents that do not contain DEET will not repel mosquitoes. Repellent with DEET can be applied directly to skin or clothing. Lower concentrations of DEET will work, but will not last as long. The American Academy of Pediatrics recommends that DEET not be used on children less than 2 months old. Follow the instructions on the product label. To find out more about West Nile, go to the CDC website at www.cdc.gov/westnile or the Oklahoma State Department of Health at www.ok.gov/health.
Fort Sill is prepared to respond if there is an outbreak of the virus, said Tom Way, pest control supervisor for contractor PCSI. They are contracted by the Fort Sill Directorate of Public Works to maintain the mosquito abatement program.
"We monitor the creeks and drainage ditches on post to make sure there are no infestations. If we do find possible infestation we will put clay blocks laced with larvicide in places where there's standing water or in sewer drains," Way said. "We are prepared to do spraying and fogging on post if necessary, but we haven't had to fog since June because it has been so dry. That could change if it starts to rain a lot."
"We are surveying and trapping mosquitoes when they are there, and we're ready to respond. We've educated our health care providers about West Nile and what to look for if patients present symptoms. We just don't want people to panic if they get bit by a mosquito," Teague said.