To me the allure of infectious diseases is that you never know what is around the next corner. Because we live in a world teeming with microbes--many of which are undiscovered--hearing about a novel infectious disease is not unexpected but is always exciting.
Much of the cutting edge research in infectious disease centers on pathogen discovery. In this quest certain places, animals, and humans are more fertile than others. For example, bush meat hunters and abattoir workers are frequent targets for emerging infections because these individuals live on the human-animal interface. Similarly, looking for pathogens that infect primate species is also fruitful because of the close evolutionary relationship between humans and other primates.
In recent decades and years, however, several new infectious diseases have been linked to ticks. Lyme Disease is probably the most well-known but more recently diseases such as the Heartland Virus, STARI, a novel cause of Ehrlichiosis, and SFTS virus have come to light.
Ticks have an intimate relationship with humans because they gain direct access to our bloodstream during their blood meal, giving the microbes they harbor unrivaled access.
The latest microbe to capture the headlines is the interestingly named Bourbon Virus. This virus, responsible for the death of a man in Kansas, is tick-borne as well and its discovery is the direct result of improved diagnostic capabilities and the increasing recognition that it is important to not allow unexplained infectious disease syndromes to remain undiagnosed, points I made to USA Today.
It's not clear at this point how widespread this virus is in humans and ticks or how frequently severe disease results, but all are important questions to be answered.