**2.2 Analysis**

Data points consisted of the number of mosquitoes from each of the three species caught in a given trap on a given date. The unit of trap-night is used to describe the number of traps over the number of nights used to survey for each site.


*1 All traps except BG Sentinel traps were baited with approximately five pounds of dry ice in a plastic cooler with a hole in the bottom. The BG Sentinel traps were baited with dry ice and a commercial attractant (BG lure). 2 Data were transformed as the square root of (x + 0.1). The means in the lower position of each couplet are the backtransformed means of the transformed data. When means in a column are followed by the same letter, the means of transformed data are not statistically different (Tukey's mean separation test; alpha = 0.05).*

#### **Table 1.**

*Arithmetic mean (upper value of each couplet) and back transformed mean of transformed trapping rates of three abundant mosquito species caught in three types of trap in southern Missouri (2016–2018).*


*1 Data were transformed as the square root of (x + 0.1). Statistical analysis was done on transformed data but the means reported here are the arithmetic means of the original data and the back-transformed means of the transformed data. Means of transformed data (represented by backtransformed means) within each column followed by the same lower case letter are not significantly different (Tukey's mean separation test; alpha = 0.05).*

#### **Table 2.**

*Arithmetic mean (upper value of each couplet) and back-transformed mean of trapping rates (mosquitoes/ trap-night) for three species caught in CO2-baited CDC traps in four ecoregions of southern Missouri (summer, 2016–2018). The value in the lower position of each couplet is the back-transformed mean of the transformed data for trapping rate.*

## *Survey for a Vector of Zika Virus and Two Other Mosquito Species in Four Ecoregions… DOI: http://dx.doi.org/10.5772/intechopen.94499*

The survey consisted of a total of 653 trap-nights. The number of trap-nights for each trap type and ecoregion combination is reported in **Tables 1**–**4**. The data did not display a normal distribution and many data points reflected no catch ("0"); therefore, all data were transformed by taking the square root of (x + 0.1) where x was the number of mosquitoes of a given species caught in a single trap. This transformation appeared to improve the distribution of the data. For instance, the non-transformed data for *Ae. albopictus* caught in the CDC light trap had a skewness score of 2.92 and a kurtosis score of 11.23. After transformation, those scores were reduced to 1.21 and 1.01, respectively. Both transformed scores are below the recommended maximum thresholds recommended by West [11]. We used transformed data for all subsequent analyses and reported the results with back transformed


*1 Data were transformed as the square root of (X + 0.1). Statistical analysis was done on transformed data but the means reported here are the arithmetic means of the original data and the back-transformed means of the transformed data. Means of transformed data within each column followed by the same lower case letter are not significantly different (Tukey's mean separation test; alpha = 0.05).*

#### **Table 3.**

*Arithmetic mean (upper value of each couplet) and back-transformed mean of trapping rates (mosquitoes/ trap-night) for three species caught in CO2-baited fay-prince omnidirectional traps in four ecoregions of southern Missouri (summer, 2016–2018). The value in the lower position of each couplet is the back-transformed mean of the transformed data.*


*1 Data were transformed as the square root of (X + 0.1). Statistical analysis was done on transformed data but the means reported here are the arithmetic means of the original data and the back-transformed means of the transformed data. Means of transformed data within each column followed by the same lower case letter are not significantly different (Tukey's mean separation test; alpha = 0.05).*

*2 The BG Sentinel trap was not used in the Dissected Till Plans during any of the three years of the survey.*

#### **Table 4.**

*Arithmetic mean (upper value of each couplet) and back-transformed mean of trapping rates (mosquitoes/ trap-night) for three species caught in BG sentinel traps in three2 ecoregions of southern Missouri (summer, 2016–2018). The value in the lower position of each couplet is the back-transformed mean of the transformed data.*

means. Because trap catches for each trap type were significantly different for at least one species, we analyzed the trap catches by ecoregion separately for each trap type. We used the data for the most abundant species from each of three genera for the comparison: *Anopheles, Aedes* and *Culex*. These were also the three most abundant species in the entire survey regardless of genus. We calculated the mean trap catch for each species by ecoregion using an unbalanced analysis of variance in the PROC GLM of SAS, with mean separation using a Tukey's HSD test.

The Missouri Department of Health and Senior Services contracted this survey to the Master of Public Health Program and the Ozark Public Health Institute of Missouri State University in Springfield. (Contract #AOC16380144).
