The evaluation of mosquito production and measures to minimize mosquitoes in stormwater treatment structures to prevent the spread of mosquito-borne diseases

To evaluate the prevalence of state and federally mandated stormwater treatment structures and mosquito production as a result of these structures, a nationwide survey was conducted of governmental agencies concerned with stormwater and urban runoff management, public health (in the form of mosquito control and surveillance), or both. Results suggest these structures present a potential public health concern nationwide for the spread of mosquito borne diseases. There is a strong need for greater communication and collaboration among agencies affected by this situation. Belowground stormwater treatment structures are of particular concern not only due to the propensity of these systems to promote conditions favorable to the development of vector mosquitoes but because they are difficult to locate, access, and monitor for mosquito production. Waters from eleven belowground stormwater treatment devices (BMPs) from five treatment technologies were sampled regularly to evaluate their capacity to support rapid development of the West Nile virus (WNV) vector, Culex quinquefasciatus. Results suggest that these structures can not only promote rapid development of mosquito vectors but can remain amenable to replication of WNV in adult mosquitoes longer each year than for resting sites aboveground. Long term measures to minimize mosquitoes in these systems need to be addressed to aid agencies concerned with public health. The effects of structural characteristics of stormwater treatment systems on mosquito oviposition in both simulated and actual systems in southern California were evaluated. Findings suggest that the modification of structural elements such as the number of pickholes within manhole covers, may be effective long term measures that can be utilized by public health agencies to prevent the spread of mosquito-borne diseases. Recommendations for aggressive public health policies to prevent the spread of mosquito-borne diseases are discussed.