Lyme disease is diagnosed clinically based on symptoms, objective physical findings (such as EM, facial palsy, or arthritis), or a history of possible exposure to infected ticks, as well as serological blood tests. The EM rash is not always a bull's eye, i.e., it can be solid red.
Rule of Thumb for Changing Filters. The rule we have followed for 18 years in the filtration industry is to change filters every 6 to 12 months. Six months is almost always optimum, especially in commercial/office settings, and twelve months is as long as you want to go no matter what.
Do I need to replace filters, and if so, how often? Most evaporative cool moisture humidifiers use replaceable wick filters, and these should be changed every 2 months on average (wick filter life varies depending on your specific humidifier model, frequency of use, and your water's mineral content).