The Louisville Metro Department of Public Health and Wellness recently found mosquitoes carrying West Nile virus in a surveillance trap in the Tyler Park neighborhood. That discovery led Metro Health to fog parts of the area to help reduce risk.
Matthew Vanderpool, an environmental health specialist and entomologist with Louisville Metro Public Health and Wellness, shares some ideas for keeping mosquitoes at bay this summer.
This interview has been edited for length and clarity.
Ayisha Jaffer: So Matthew, how serious is mosquito activity in Louisville right now, and what kind of risk does that pose for people outdoors?
Matthew Vanderpool: Sure. So we're always going to have mosquitoes outside. I mean, that's where they belong. That's hopefully where all of our bugs are. They're not like coming into our houses, but we do have diseases that we see every single year in Louisville. The primary one that we see is West Nile virus. We've had West Nile virus in the community since 2002.
The disease itself, most of the time is not one of those run for the hill sort of diseases. Not all mosquitoes carry it. There's like one or two different species in town that carry it out of those 52 different species that we have. Not all of the ones of that particular species have it. They actually bite birds that carry it as a reservoir, and then the bird's blood goes into the mosquito, and then they have the virus in them. They have to survive long enough to then bite somebody else, and then there's the chance that they don't actually pass the virus off.
So the odds are against you getting the virus. Once you get the virus, you have like a one-in-100 chance of having symptoms, and then even after that, you have a one-in-150 chance of having the severe form of the disease. But that said, we take all of it very seriously, because you don't want to be the one person that gets that severe form of the disease, because it can be absolutely debilitating, because it's a viral infection of the brain. It's an encephalitis. So we take it super serious, even though the vast majority of mosquito bites are not going to be oh my gosh, I got West Nile virus.
AJ: What are the most effective ways people can protect themselves and their environment from mosquito bites?
MV: Yeah, so the best thing that people can do is to eliminate water around their house. Now, certain parts of the community only ever have, you know, one story homes. Okay, great, but how often do you actually clean out your gutters? If you have second, third story gutters, how often do you actually clean those gutters out because that can be kind of dangerous.
Any standing water, no matter how big or small it is, can breed mosquitoes. So kids’ toys, bird baths, tires are a big one, especially in certain parts of the community where people just chuck tires out in an alley. One tire can breed 75 to 100 mosquitoes and If somebody dumps off five, 500 mosquitoes every single week are inundating an entire one block area with mosquitoes.
So getting rid of anything that's going to stand in water for more than five days is your real key thing. If you're going to be outside–awesome–be outside. Don't be scared to go outside, but wear insect repellent. That way, it'll keep mosquitoes off of you and lower your chances of any bites, therefore lowering your chances for disease.
AJ: Are there any types of ingredients we should look for in repellent?
MV: Well, there's a lot of different things that have been evaluated by the EPA. Some of the top end things that work are DEET. That's kind of the old standard, but it still works really well. You have oil, lemon, eucalyptus, picaridin and IR3535. On the health department's website, we have a link to the EPA for how these have been evaluated and which ones work. Some work better for certain species of mosquitoes versus others. Some work for different amounts of time. Sometimes the amount of time is based on the percentage of active ingredient, but there's a lot of really great information on our website for people to go to and make educated choices.
