title: Modeling dynamics of culex pipiens complex populations and assessing abatement strategies for West Nile Virus.
abstract: The primary mosquito species associated with underground stormwater systems in the United States are the Culex pipiens complex species. This group represents important vectors of West Nile virus (WNV) throughout regions of the continental U.S. In this study, we designed a mathematical model and compared it with surveillance data for the Cx. pipiens complex collected in Beaufort County, South Carolina. Based on the best fit of the model to the data, we estimated parameters associated with the effectiveness of public health insecticide (adulticide) treatments (primarily pyrethrin products) as well as the birth, maturation, and death rates of immature and adult Cx. pipiens complex mosquitoes. We used these estimates for modeling the spread of WNV to obtain more reliable disease outbreak predictions and performed numerical simulations to test various mosquito abatement strategies. We demonstrated that insecticide treatments produced significant reductions in the Cx. pipiens complex populations. However, abatement efforts were effective for approximately one day and the vector mosquitoes rebounded until the next treatment. These results suggest that frequent insecticide applications are necessary to control these mosquitoes. We derived the basic reproductive number (ℜ0) to predict the conditions under which disease outbreaks are likely to occur and to evaluate mosquito abatement strategies. We concluded that enhancing the mosquito death rate results in lower values of ℜ0, and if ℜ0<1, then an epidemic will not occur. Our modeling results provide insights about control strategies of the vector populations and, consequently, a potential decrease in the risk of a WNV outbreak.
authors.affiliation: Department of Mathematics and Computational Science, University of South Carolina Beaufort, Bluffton, South Carolina, United States of America.
authors.forename: Kasia A
authors.initials: KA
authors.lastname: Pawelek
authors.affiliation: Department of Mathematics and Computational Science, University of South Carolina Beaufort, Bluffton, South Carolina, United States of America.
authors.forename: Patrick
authors.initials: P
authors.lastname: Niehaus
authors.affiliation: Department of Mathematics and Computational Science, University of South Carolina Beaufort, Bluffton, South Carolina, United States of America.
authors.forename: Cristian
authors.initials: C
authors.lastname: Salmeron
authors.affiliation: Beaufort County Mosquito Control, Beaufort, South Carolina, United States of America.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Hager
authors.affiliation: Beaufort County Mosquito Control, Beaufort, South Carolina, United States of America.
authors.forename: Gregg J
authors.initials: GJ
authors.lastname: Hunt
mesh_terms: D000818:Animals; D003465:Culex / Q000821:virology*; D004196:Disease Outbreaks / Q000517:prevention & control*; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D007303:Insect Vectors / Q000821:virology*; D007306:Insecticides; D008297:Male; D015233:Models, Statistical; D009032:Mosquito Control / Q000379:methods / Q000706:statistics & numerical data*; D011157:Population Dynamics; D011722:Pyrethrins; D012098:Reproduction; D012621:Seasons; D014481:United States / Q000453:epidemiology; D014901:West Nile Fever / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission* / Q000821:virology; D014902:West Nile virus / Q000502:physiology
chemical_list: D007306:Insecticides; D011722:Pyrethrins