Study shows where Zika, West Nile outbreak would hit hardest in San Antonio
SAN ANTONIO--A breakthrough study has just been finished by researchers at Texas A&M San Antonio that tracks disease carrying mosquitoes in our area. At least three mosquitoes have been found here with West Nile virus, and at least 16 people have Zika, although none have gotten it from mosquitoes locally.
Since June, 11th, students have been checking 118 mosquito traps, once a week for 12 weeks. You can see see where each trap is placed by the dot, color coordinated by neighborhood on the map. They range from Hill Country to the Southside. Over 400 people volunteered for this study after one of our stories aired in April, asking for volunteers.
"The community of San Antonio is really big, really unique,” says associate professor Dr. Megan Wise de Valdez. She says a vector disease surveillance study on this big of a city, with these traps has never been done before.
"We're really paying attention to two types of mosquitoes, aedes agypti, which transmits Zika, dengue and chikungunya and then Culex quinquefasciatus which transmits West Nile.”
The results are compiled after tallying up the small portion of the population that was captured, and broken down by area. It’s a 12 week average of each type of mosquito found. The Zika carrying mosquito was most common in four areas around town. On the Northeast Side just south of 35, on the North Side, just inside 1604, the Westside, before loop 410, and Southside near 1604.
The West Nile carrying mosquito on the other hand, was much more prevalent overall. In Hill Country, Northside just south of 1604, , and in the King William neighborhood.
"So the question is, what is it about these zones that is giving us this trend, and that's what we need to try to find out,” Dr. Wise de Valdez says.
The study also showed just how important rain is to a thriving mosquito population.
"This dotted line is precipitation, notice two weeks later, boom.."
The mosquito population exploded around mid-june. You can see by the green line, it was mostly the West Nile carrying mosquito. The Zika carrying mosquito, along the solid blue line, followed a different path.
"It seems like the aedes agypti tends to rise a little bit as we get a little bit further in the summer,” she says.
This preliminary study lays the foundation for detailed work in the years to come, "Science is a long process, you can only bite off so much at a time,” she says.
This study showed there is a varying population from home to home, neighborhood to neighborhood. Next they'll try to find out why.
"Is it the house itself or is it the neighborhood or is it whether it backs up against wooded areas or is it the type of water sources nearby?” she asks.
As the mosquito patrol hunts down that answer, remember, the best way to keep the population in check at home is to dump out any and all standing water.
By Andrew Lofholm