The Texas Department of State Health Services has confirmed one case of West Nile Virus in the state this year. But after last year’s record West Nile outbreak, state and local officials are already working to slow the spread of the mosquito-borne disease.
In 2012 in Texas officials reported 1,024 cases of West Nile fever and another 844 cases of the more serious form of the virus, neuroinvasive West Nile disease, confirmed by the DSHS. Of those cases, 89 were fatal.
Johnson County saw seven confirmed cases of West Nile fever, and six cases of neuroinvasive West Nile in 2012.
The only confirmed case of West Nile in a human in 2013 —a neuroinvasive case — was reported in Anderson County. But mosquitoes positive for the West Nile virus have been found in Collin, Denton, Dallas and Brazoria counties, and one case of West Nile in a horse has been confirmed in Grimes County.
Johnson County’s approach to combating West Nile, Emergency Management Coordinator Jamie Moore said is to focus on public education.
“We can’t spray the whole county. That just isn’t feasible,” Moore said. “But what we can do is make sure that people know what to do to avoid getting West Nile.”
He said that last year, as the number of West Nile infections steadily grew, the Centers for Disease Control handed out grants to help fund prevention efforts. Johnson County used some of its grant money to buy a stockpile of “mosquito dunks” to distribute to residents to help keep the insects from breeding in standing water.
This year, however, since there’s been no spike in West Nile infections, there is no grant money. And that means the county has no free mosquito dunks.
Moore said officials have focused in recent weeks on responding to the May 15 tornadoes that damaged parts of Johnson County.
“But you are going to start seeing more emphasis on West Nile prevention in the next three or four weeks. We are about to really start ramping up those efforts,” Moore said.
In Burleson — where three human cases were reported in 2012 and five mosquito traps tested positive — city staffers in early April laid out a comprehensive mosquito control plan that called for setting more mosquito traps and for spraying immediately if a trap tests positive for West Nile. The city council approved the plan, which includes hiring a part-time employee, from May through October, to check mosquito traps — including counting mosquitoes in the traps as suggested by the Centers for Disease Control — and to conduct larvicide sprayings. If positive traps are found, the city will bring in an outside contractor to conduct spraying for adult mosquitoes.
Lisa Duello, Burleson’s director of neighborhood services, said the city is in the process of hiring the part-timer to handle mosquito control, but that mosquito trapping and sampling efforts have been underway since the first of May.
“We are trapping a lot of mosquitoes, but all the tests so far have been negative” for West Nile, Duello said.
Officials in Cleburne are treating problem areas, such as stagnant creek pools and unused swimming pools, with larvicide, Fire Chief Clint Ishmael said.
He said that last year, the city had a big problem with swimming pools left full of water when homes were foreclosed on becoming prime breeding grounds for mosquitoes.
“We would go in and drain them when we could, and if we couldn’t drain them, we would treat them,” Ishmael said.
The city is waiting on mosquito traps to arrive, and will begin trapping and testing mosquitoes once the traps arrive and can be installed, Ishmael said. “Then if we reach a certain threshold, a certain number of mosquitoes testing positive for West Nile, then we will spray in those targeted areas. If we get a confirmed human case of West Nile, then we could spray a larger area, or even city-wide.”
But spraying only kills mosquitoes that actually come in contact with the insecticide.
“In 10 minutes, that spray settles and any mosquitoes that come through after that aren’t affected. That’s why we get our best results from prevention,” Ishmael said.
That’s why, he added, Cleburne will focus efforts on educating residents about how to prevent mosquitoes from breeding.
“Citizens are our first line of defense. Just eliminating the standing water around your home reduces their breeding grounds, and that is 90 percent of the battle for us.”
Joshua hasn’t started sampling yet, but has been spraying for mosquito larvae in areas where there tends to be standing water since the first of May, also, Director of Operations Mike Peacock said.
“We have been treating the areas with standing water, but it really hasn’t gotten hot enough for long enough yet for the mosquitoes to be a real problem,” Peacock said.
Alvarado does not have a regular spraying program, City Manager Clint Davis said, “but we do treat areas with standing bodies of water when someone calls us to report a problem.”
Davis said Alvarado can’t engage in regular spraying or sampling programs “with no support from Johnson County, but we are trying to be as proactive as we possibly can.”
Davis said that although the city has no spraying program — either for larvae or adult mosquitoes — they can contract for those services if necessary.
Grandview City Secretary Sherry Reeves said the city has “already started spraying whenever possible, when the wind is not too strong” to kill mosquito larvae. She said the city has already conducted some sampling, finding no positive traps so far.
Neither Godley nor Rio Vista have mosquito control programs in place, and Keene City Administrator Bill Guinn didn’t return calls seeking comment by press deadline.
As Moore noted, though, much of the responsibility for avoiding infection falls on the shoulders of individuals.
“About 70 percent of the people who were infected last year didn’t take any personal protection measures,” Moore said. “That means they weren’t using [an insect repellent that included DEET). They weren’t staying in at dawn and dusk, when the mosquitoes are worse.”
According to the CDC, the best way to avoid being infected by West Nile Virus is to avoid being bitten by mosquitoes. And the best way to avoid being bitten by mosquitoes is to start with an Environmental Protection Agency-approved mosquito repellent. For use on skin and clothing, the CDC recommends products that include the conventional repellents DEET or Picaridin, or those that include the biopesticide repellents — derived from natural materials — Oil of Lemon Eucaplyptus or PMD and IR3535.
When it comes to repellents for use on clothing, shoes, bed nets and camping gear, the CDC recommends products that include permethrin. Permethrin-treated clothing repels and kills ticks and other arthropods as well as mosquitoes, and can continue to work even after repeated laundering.
Remember that mosquitoes are most active at dusk and dawn. So use insect repellent and wear long sleeves and pants if you have to be outside then. If you don’t have to be outside, stay inside. And make sure to have good screens on your windows and doors to keep mosquitoes out.
In addition, the CDC says get rid of mosquito breeding sites by emptying standing water from flower pots, buckets and barrels. Change the water in pet dishes and replace the water in bird baths weekly. Drill holes in tire swings so water drains out, and keep children’s wading pools empty and on their sides when they aren’t being used.
About 80 percent of those infected with West Nile Virus won’t have any symptoms, according to the CDC. Most of the remaining 20 percent will have fever, headache and body aches, nausea and vomiting, and sometimes swollen lymph glands or a skin rash on their chest, stomach and back.
Only about one in 150 contract the most serious version of West Nile, the neuroinvasive West Nile. Symptoms are high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. These symptoms may last several weeks, and neurological effects may be permanent.