Potential of the Sterile Insect Technique for Control of Deer Ticks, $\textit{Ixodes scapularis}$

TL;DR

This study models the potential of the Sterile Insect Technique to control deer tick populations, highlighting the importance of thorough dispersal and high rearing costs for effective implementation.

Contribution

It develops a population model for deer ticks incorporating various ecological factors to evaluate SIT feasibility and optimal deployment strategies.

Findings

Control duration estimated at about eight years.

Thorough dispersal of sterile ticks is critical for success.

High rearing and deployment costs may limit practical application.

Abstract

The deer tick, $\textit{Ixodes scapularis}$, is a vector for numerous human diseases, including Lyme disease, anaplasmosis, and babesiosis. Concern is rising in the US and abroad as the population and range of this species grow and new diseases emerge. Herein I consider the potential for control of $\textit{I. scapularis}$ using the Sterile Insect Technique (SIT), which acts by reducing net fertility through release of sterile males. I construct a population model with density-dependent and -independent growth, migration, and an Allee effect (decline of the population when it is small), and use this model to simulate sterile tick release in both single- and multi-patch frameworks. I test two key concerns with implementing $\textit{I. scapularis}$ SIT: that the ticks' lengthy life course could make control take too long and that low migration might mean sterile males need thorough manual dispersal to all parts of the control area. Results suggest that typical $\textit{I. scapularis}$ SIT programs will take about eight years, a prediction near the normal range for the technique, but that thorough distribution of sterile ticks over the control area is indeed critical, increasing expense substantially by necessitating aerial release. With particularly high rearing costs also expected for $\textit{I. scapularis}$, the latter finding suggests that cost-effectiveness improvements to aerial release may be a prerequisite to $\textit{I. scapularis}$ SIT.