The increasing prevalence of Lyme disease and the emergence of other tick-associated human diseases in the United States have become a major public health concern. A wide variety of personal protection measures and tick control strategies have been used or investigated to reduce contact between ticks and humans, reduce tick abundance, or lower the prevalence of tick-borne agents in the ticks. These methods have generally been applied or evaluated as single interventions and other than some early computer model simulations, studies applying integrated tick management approaches are few. In this paper, we review surveyed human behaviors and risks for exposure to ticks, concepts pertinent to integrated pest management for ticks, simulation models, various tick control strategies, integrated tick management studies, and highlight what is needed going forward. Increased education and communication between physicians and veterinarians is essential to address tick-associated diseases in a ‘one health’ approach and unify the animal and human branches of medicine to identify, treat, and implement preventive measures. Novel simulation models using more recent empirical data on tick population dynamics, hosts, efficacy of various combinations of interventions, human exposure elements, and utilization of personal and environmental measures will help us better understand the interactions of integrated strategies for tick population management. Many questions remain related to the ecology of ticks and tick-borne pathogens, observed and modeled efficacy of various integrated interventions, human behavior and exposure to tick bite and disease risk, comparative cost of interventions, and the acceptance and use of prevention and tick control tools.

Ticks and tickborne diseases are increasingly becoming a major health concern for humans, domesticated animals, and livestock. Reported cases of bacterial and protozoan tickborne disease doubled in the United States between 2004 and 2016. More than 90% of the nearly 60,000 cases of nationally notifiable vectorborne diseases reported in 2017 were linked to ticks. As the geographic ranges of multiple tick species continue to expand, invasive tick species are being discovered, new tickborne pathogens are emerging, and coinfections in ticks are surging. Rising global temperatures, ecologic changes, reforestation, and increases in commerce and travel are all important underlying factors influencing the rate and extent of range expansion for ticks and tickborne pathogens.

Japanese barberry (Berberis thunbergii de Candolle) is a thorny, perennial, exotic, invasive shrub that is well established throughout much of the eastern United States. It can form dense thickets that limit native herbaceous and woody regeneration, alter soil structure and function, and harbor increased blacklegged tick (Ixodes scapularis Say) populations. This study examined a potential causal mechanism for the link between Japanese barberry and blacklegged ticks to determine if eliminating Japanese barberry could reduce tick abundance and associated prevalence of Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner). Japanese barberry was controlled at five study areas throughout Connecticut; adult ticks were sampled over three years. Each area had three habitat plots: areas where barberry was controlled, areas where barberry remained intact, and areas where barberry was minimal or absent. Sampled ticks were retained and tested for B. burgdorferi presence. At two study areas, temperature and relative humidity data loggers were deployed in each of the three habitat plots over two growing seasons. Intact barberry stands had 280 ± 51 B. burgdorferi-infected adult ticks/ha, which was significantly higher than for controlled (121 ± 17/ha) and no barberry (30 ± 10/ha) areas. Microclimatic conditions where Japanese barberry was controlled were similar to areas without barberry. Japanese barberry infestations are favorable habitat for ticks, as they provide a buffered microclimate that limits desiccation-induced tick mortality. Control of Japanese barberry reduced the number of ticks infected with B. burgdorferi by nearly 60% by reverting microclimatic conditions to those more typical of native northeastern forests.

In many Connecticut forests with an overabundance of white-tailed deer (Odocoileus virginianus Zimmermann), Japanese barberry (Berberis thunbergii DC) has become the dominant understory shrub, which may provide a habitat favorable to blacklegged tick (Ixodes scapularis Say) and white-footed mouse (Peromyscus leucopus Rafinesque) survival. To determine mouse and larval tick abundances at three replicate sites over 2 yr, mice were trapped in unmanipulated dense barberry infestations, areas where barberry was controlled, and areas where barberry was absent. The number of feeding larval ticks/mouse was recorded. Adult and nymphal ticks were sampled along 200-m draglines in each treatment, retained, and were tested for Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner) presence. Total first-captured mouse counts did not differ between treatments. Mean number of feeding larval ticks per mouse was highest on mice captured in dense barberry. Adult tick densities in dense barberry were higher than in both controlled barberry and no barberry areas. Ticks sampled from full barberry infestations and controlled barberry areas had similar infection prevalence with B. burgdorferi the first year. In areas where barberry was controlled, infection prevalence was reduced to equal that of no barberry areas the second year of the study. Results indicate that managing Japanese barberry will have a positive effect on public health by reducing the number of B. burgdorferi-infected blacklegged ticks that can develop into motile life stages that commonly feed on humans.

Pathogens transmitted by ticks are the leading cause of arthropod-associated human diseases in the United States and managing the risk of exposure to potentially infected ticks is of vital public health importance. A 3-year integrated tick management program to control blacklegged ticks, Ixodes scapularis, the primary vector for the pathogenic agents of Lyme disease, human anaplasmosis, and babesiosis, was implemented in the town of Redding in southwestern Connecticut beginning in 2013. Combinations of white-tailed deer, Odocoileus virginianus, reduction, area application of the entomopathogenic fungus Metarhizium anisopliae, and fipronil-based rodent bait boxes were evaluated for their ability to reduce nymphal I. scapularis over 3 years. Interference from local hunters prevented sufficient, sustained deer removal previously reported to negatively impact I. scapularis abundances (i.e., <5 deer/km²). The combination of fipronil-based bait boxes and broadcast application of M. anisopliae had the most impact of any treatment combination; questing nymphs were reduced 78–95% within each year and Borrelia burgdorferi-infected questing nymphal I. scapularis encounter potential was reduced by 66% as compared with no treatment in the third year of the study. A combination of the broadcast application of M. anisopliae and small rodent-targeted fipronil-based bait boxes is an effective low-toxicity integrated approach that significantly reduced encounters with B. burgdorferi-infected questing nymphal I. scapularis on individual properties.