Only a few months remain before the winter cold will provide the Arlington community protection from mosquitoes and the West Nile virus they carry. Until then, the city of Arlington is continuing efforts to mitigate the virus through targeted ground spraying.
The process of responding to the West Nile virus season has remained largely unchanged, even in the midst of the pandemic, said Susan Schrock, city of Arlington communication coordinator. Traps are strategically placed around the city and mosquitos are collected once a week. After the mosquitoes are sent to the county for testing, sprays are conducted where traces of West Nile virus were found.
“We're really focusing on targeting the adult mosquito population close to where a positive trap has been identified,” Schrock said. “And so we only spray within a half-mile radius of the trap over a two-night period.”
Mathematics professor Christopher Kribs said West Nile is a virus transmitted by mosquito bites. It affects animals such as birds and horses far more than it usually does humans. Kribs studied transmission cycles of Chagas disease in 2003, and published a textbook on mathematical biology in 2015, that detailed how to create biological models for topics like epidemiology and immunology.
“Most humans who get infected by West Nile virus don't ever actually show symptoms,” he said. “So it's sort of an invisible, you know, little infection that the body eventually fights off.”
Kribs said when infected people do show symptoms, they are similar to the flu. There is a possibility for more serious illness in a small percentage of cases.
Schrock said the West Nile virus season begins as early as April. The first positive case this year was reported the week of July 26.
There have been 10 weeks of targeted ground spraying this year with one to three positive mosquito cases each week, she said.
The City of Arlington uses a water-based permethrin product for mosquito control, according to the city’s website. The Environmental Protection Agency determined this product would not pose an unreasonable risk to people, animals or the environment.
The city recommends those who have a sensitivity to chemicals or conditions such as asthma avoid going outdoors during the application period, which usually occurs at night.
Schrock recommends making sure to use repellent when going outside and to wear long sleeves and jeans, especially at dusk and dawn, as preventive measures against contracting West Nile.
Kribs said he advises homeowners to eliminate any stagnant water in outdoor areas to prevent mosquito breeding areas.