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■Bio-mathematics, Statistics and Nano-Technologies: Mosquito Control Strategies

When designing the regions for spraying or fogging or ground placement of insecti-

cides, for example, many considerations must be taken into account. These include the

type of mosquito being eradicated, their flight ranges, and flight patterns. Also of con-

cern are the demographics of the region to be sprayed, including vulnerable populations,

and its topography. Often political issues must be taken into account, e.g. public opposition

to spraying, which is very similar to the matters of concern when designing voting districts.

The author and colleagues developed the convexity ratio [1] to measure the shape of

voting districts. A district is nicely shaped if it is nearly convex, i.e. CR(D) > 0.5, where

D is the district being measured and CR is its convexity ratio. Otherwise it is poorly shaped.

The convexity ratio is a measure of how close a planar region D is to being convex, mean-

ing any two points lying in D can be connected by a straight line lying entirely in D.

CR(D) equals the area of the largest convex set within D, the endogon, divided by the area

of the convex hull of D, i.e. the smallest convex set containing D, or the exogon. The author

and colleagues applied this to the redistricting problem in [2] and indicated applications to

other areas of Business and Industry. In [2] the entire State of Texas in the USA was com-

pletely redistricted with the goal of having each district as close to convex as possible. In

this paper we apply the same techniques, which utilized ArcGIS amongst other methods,

to design mosquito control districts which are also as close to convex as possible. This will

enhance the eradication of the mosquitos in question as they can fly in any direction from

a given starting point, creating a convex area of possible paths.

This chapter is organized as follows: In Section 8.2 we look at different designs of

mosquito abatement districts from varying countries and regions. In Section 8.3 the flight

patterns of different types of mosquitos are examined. Section 8.4 includes a description of

the redistricting mentioned above. The methodology used in that application is then applied

to the design of mosquito control districts. We conclude with an analysis of our results in

Section 8.5.

8.2

DESIGNS OF CURRENT MOSQUITO ABATEMENT REGIONS

What follows are descriptions of regions in the United States and Canada where spray-

ing or fogging was applied:

8.2.1

Rhode Island, USA [3]

8.2.1.1

Mosquito Control Measures: 2019 Pesticide Applications

In 2019, aerial spraying occurred in four areas of Rhode Island that state officials as-

sessed to be at critical risk for the Eastern Equine Encephalitis (EEE) virus.

• September 8 - 10, 2019

In all, the state treated parts of 21 communities over three nights, from September

8 to 10, with a pesticide formulated to kill adult mosquitos. The flight crew used

the pesticide, called Anvil 10 + 10, at an extremely low concentration, dispersing