Q: I keep my “septic” system (OWTS) maintained all the time, why should I care about mosquitoes these systems may produce?
A: The answer is that because mosquitoes can fly, even if you keep your OWTS working, your neighbor’s unmaintained system may be producing mosquitoes that can transmit WNV. In fact, according to our partners at the Pontchartrain Conservancy, more than half of OWTS in St. Tammany are not being maintained—potentially every other house on your block!
A collaboration with scientists from the Centers for Disease Control and Prevention has determined that St. Tammany residents that live within a half mile from a sewage-polluted ditch experience 5.9 times more WNV vector mosquitoes than those that live farther. Given the pervasiveness of OWTS in St. Tammany Parish most residents (~87%) live within a half mile – the flight range of the southern house mosquito—of a sewage-polluted ditch that may produce these mosquitoes. CDC researchers analyzed St. Tammany mosquito trap data from 2017-2018 to assess the spatial relationships of sewage-polluted ditches, southern house mosquitoes and WNV. An ongoing collaboration with these researchers promises a more detailed description of the mechanisms underlying the sewage-southern house mosquito connections. Stay tuned for future updates on this project.