Environmental and social-demographic predictors of the southern house mosquito Culex quinquefasciatus in New Orleans, Louisiana

Authors: MOISE, IMELDA - University Of Miami; RIEGEL, CLAUDIA - New Orleans Mosquito, Termite & Rodent Control Board; Muturi, Ephantus

Submitted to: Parasites & Vectors
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2018
Publication Date: 4/17/2018
Citation: Moise, I.K., Riegel, C., Muturi, E.J. 2018. Environmental and social-demographic predictors of the southern house mosquito Culex quinquefasciatus in New Orleans, Louisiana. Parasites & Vectors. 11:249. doi.org/10.1186/s13071-018-2833-5.
DOI: https://doi.org/10.1186/s13071-018-2833-5

Interpretive Summary: Flooding events have become fairly common throughout the world yet our understanding of their impact on disease vectors such as mosquitoes is limited. We used Geographical Information Systems (GIS) and historical weather, socio-demographic, and mosquito surveillance data from post-Katrina New Orleans to identify the risk factors for mosquito production in the aftermath of a flooding disaster. Adult mosquitoes were collected using CDC gravid traps between March and September during the years 2006, 2008, 2009, and 2010. Socio-demographic data were obtained from the 2005–2009 United States Bureau of the Census American Community Survey and the City of New Orleans Department of Code Enforcement. Land-use and land-cover data used in geospatial analysis were derived from Landsat 7 Enhanced Thematic mapper satellite imagery and processed using ERDAs image processing software. Average weekly temperatures were positively associated with Cx. quinquefasciatus density in three of the four years (2006, 2008, and 2009). In addition, proximity to open waters, developed low intensity areas, flood depth, woody wetlands and blighted properties were positively associated with Cx. quinquefasciatus density in at least one of the two years that were examined (2009 and 2010) while abandoned swimming pools were negatively associated with Cx. quinquefasciatus density. Our results show that GIS can effectively be used to characterize and identify the environmental and socio-demographic predictors of mosquito abundance during flooding events and should be incorporated into vector surveillance and control plans to identify high priority areas for targeted mosquito control at a landscape scale.

Technical Abstract: Flooding events have become common throughout the world yet our understanding of how these events affect the spatial and temporal distribution of disease vectors such as mosquitoes is limited. This knowledge can guide development of effective and timely strategies for mitigating mosquito-borne disease outbreaks in the aftermath of flood disasters. This study examined the influence of environmental and social factors on the spatial and temporal distribution of the southern house mosquito Culex quinquefasciatus in post-Hurricane Katrina New Orleans (2006-2010). Adult mosquitoes were collected using CDC gravid traps between March and September during the years 2006, 2008, 2009, and 2010. Socio-demographic data were obtained from the 2005–2009 United States Bureau of the Census American Community Survey and the City of New Orleans Department of Code Enforcement. Land-use and land-cover data used in geospatial analysis were derived from Landsat 7 Enhanced Thematic mapper satellite imagery and processed using ERDAs image processing software. Significantly, more mosquitoes were collected in 2009 and 2010 compared to 2006 and 2008. Peak mosquito densities occurred much earlier in 2009 and 2010 (May) compared to 2006. Average weekly temperatures but not precipitation were positively associated with Cx. quinquefasciatus density in three of the four years (2006, 2008, and 2009). In addition, proximity to open waters, developed low intensity areas, flood depth, woody wetlands and blighted properties were positively associated with Cx. quinquefasciatus density in at least one of the two years that were examined (2009 and 2010) while abandoned swimming pools were negatively associated with Cx. quinquefasciatus density. Our results show that GIS can effectively be used to characterize and identify the environmental and socio-demographic predictors of mosquito abundance during flooding events and should be incorporated into vector surveillance and control plans to identify high priority areas for targeted mosquito control at a landscape scale.