The proposed project addresses the Fiscal Year 2018 Tick-Borne Disease Research Program's (TBDRP's) Focus Area of "Tick Prevention," by the development of a new technologically advanced platform for tick-targeted repellency, named: Adaptive Barrier – Controlled Release Device (AB-CRD). Ticks are the number one source for vector-borne diseases in the United States, and the first line of defense is based on repelling and avoiding tick bites altogether. Current methods of avoidance include locally applied repellents as spray or cream (e.g., DEET), treating clothes with repellents (e.g., permethrin) and simply avoiding tick infested areas when possible. These methods are limited and incur many issues with adherence and compliance due to the required periodic application. Our project aims to integrate microchips technology for delivery of repellents to help overcome these limitations.

Controlled release devices allow the user to maintain a necessary concentration of the active ingredients to repel ticks. Thus, instead of a very high, toxic level of repellent which is quickly reduced to ineffective levels, the AB-CRDs can release active ingredients (AIs) in small pulses, keeping a low but still effective levels of the repellent in the immediate surroundings of the device. Current methods can be compared to watering your garden with a hose, first over-flooding the plants and shortly after, leaving them dry. In this analogy, the proposed technology platform would be drip irrigation, gently watering the plants, keeping a constant, useful amount of water for use.

Each AB-CRD contains several small reservoirs of tick repellents, each with an electronically controlled release mechanism that can pop open a small membrane that serves as the reservoir lid. We can control the number of reservoirs open at a given time and the number of lids open for each reservoir, giving us a very high level of control over release rates. These devices will be integrated in a strap or band that can be placed on the boot or around an ankle, or on other areas susceptible to tick climbing and biting. A major part of our initial work, in addition to adapting these devices for use against ticks, will be finding the best tick repellent combination that would yield the highest level of repellency. In collaboration with our experienced partners, the US Department of Agriculture and UMass Amherst, we will assay the five most popular tick repellent AIs alone and in combination. Since the AB-CRD contains several reservoirs (e.g., N = 10), we will be able to load several AIs and release each of them at its optimal rate. Proof of concept has already been accomplished for these new devices, and preliminary data indicate that combining multiple AIs produced the high repellence efficacy.

As our devices can last up to 3 months for one single-use cartridge, they will save the need to reapply repellent every few hours and thus, increase adherence and compliance significantly for Warfighters, who need maximum situational awareness and for the civilian population for whom the ease of use and long-term sustained protection will be a winning factor, especially for children. The improved protection AB-CRDs provide, along with higher rates of adherence and compliance, will be very impactful not only in saving lives, but also by greatly reducing the financial burden caused by treating Lyme disease and other diseases. Moreover, since the current diagnosis process for Lyme disease is very slow, many are treated with strong antibiotics for long periods of time due only to a suspicion of disease.

We expect that by the end of this TBDRP-funded project, we will have a working AB-CRD for military and civilian applications. The AB-CRD can be easily adjusted in a modular fashion to containing new AIs, staying at the front of the tick prevention field. The AB-CRDs will provide a new approach in tick control for personal use. AB-CRDs have been designed as a cost-effective solution for mass deployment in military and civilian settings.