Health Segment: West Nile Virus And The Drought
By Sam Baker, KERA Morning Edition Host
Dallas, TX –
At least one good thing has come out of this lengthy heat wave: far fewer human cases of West Nile Virus. We're past the peak period of the typical season for the disease, and there have been nine reported human cases statewide so far. 2010 saw more than 80. In our Monday health segment, Sam Baker talked with Morgan Kohut of Dallas County Health and Human Services. The entomologist says the drought has held West Nile at bay.
Morgan Kohut: Mosquitoes need water for their life cycle. And since we're in the drought, we are not seeing a lot of water pooling around, so the breeding isn't happening as often as it has in years past.
Sam: Though I've heard Richardson has been a bit of an exception?
Morgan: Richardson is the exception: we've had four positive mosquito pools. The only areas we're seeing a lot of mosquitoes, and it's not anything compared to previous years, is yards where they're watering on a regular basis. Now they are in Phase Two of their water restrictions, so that may alleviate some of the mosquitoes were catching there. But, as we all know, West Nile can get active very quickly, so we just have to be on our toes and be ready.
Sam: Coincidental or isolated cases of standing water happening or is there some other factor?
Morgan: The Southern House mosquito which carries West Nile, they breed in the more organic water, so it's a smaller pool, more grass clippings, stuff like that. A mosquito needs very little water to actually breed in. Watering your yards with the sprinkler system, you're going to get a little bit because your ground's a little bit more saturated than if you're not watering.
Sam: We're not out of the woods yet? The quote-unquote West Nile Season has not ended yet?
Morgan: No. We'll typically see West Nile until the end of September. But our peak in late July, early August. So, we have passed the peak time, but with the rain...
Sam: That we hopefully will get...
Morgan: ...we'll see if numbers of mosquitoes increases after, but we do our surveillance on a weekly basis, so we'll just have to see what we get and go from there.
Sam: And the testing for West Nile is still going on? No one is being lax about it because we see so few cases?
Morgan: Last time I checked, the county has set 600 traps with 400 being tested, at least. And then the city of Dallas, the city of Garland - most of the larger areas - they still have their own programs. They're also testing at the state lab in Austin.
Sam: There was a a recent story on National Public Radio that the federal government, so some degree, was cutting back on testing of mosquitoes and that some state were. Is there anything like that happening in Texas or North Texas that you know of?
Morgan: So far, the state has not limited the amount of mosquito pools that we can test. But we at Dallas County have our own labs where we will test for West Nile. So, it's a combination - most of our traps get tested here within the county and that allows us for a quicker turnaround.
Sam: When did we begin to see West Nile in this area?
Morgan: West Nile first came to Dallas County in 2002. From there, the most active season to date has been in the 2005-2006 seasons. And really, the past three years, it's been relatively low as far as both human cases and mosquito pools.
Sam: In the meantime, what can the public do to keep the number of cases down?
Morgan: Help us protect themselves by remembering "the three Ds": DEET, dress and drain. When you are outside, long sleeves, pants, if possible - I know the temperatures are very hot - and then light-colored clothing. And then, wearing some form of insect repellant, not necessarily DEET, but anything that is EPA-approved. And then the most important one? Walk around your house and look for bird baths, pet dishes, toys - anything that could possibly hold water. If you have pet dishes that are out there, change the water at least weekly, so if a mosquito does decide to lay eggs, it will not go through the full life cycle.
Morgan Kohut is an entomologist with Dallas County Health and Human Services.
For more information on West Nile Virus: