According to the CDC, more than 80,000 confirmed or probable cases of Lyme disease are reported each year. However, due to underreporting, the CDC suggests that this number may be closer to 450,000. Lyme disease is the most common vector-borne illness in the US with substantial health care costs for diagnosed patients.

Johns Hopkins School of Public Health has created a geographical monitoring system . A chart on the website documents the discovery of tickborne pathogens since 1900. These have affected people not only in the US but also in Canada, Europe, around the world. Other tickborne illnesses include babeiosis, ehrlichiosis, and anaploasmosis. While prevalence of anaplasmosis, an infection of the bacteria Anaplasma phagocytophyllum, is less common than Lyme, it is increasing. Like Lyme, it is transmitted by the black-legged tick and impacts humans, deer, horses, and dogs alike.

Accurate diagnosis of Lyme disease by the medical community continues to be a concern with early identification a priority. Of interest is the gender bias for symptoms according to the Canadian Lyme Disease Foundation -- compared to women overall, men were nearly twice as likely to test positive on the two-tier test. They had more severe symptoms and presented with larger rashes.

Research also indicates that an infection can get an upper hand from the tick saliva that hijacks some aspects of the immune system.

The skin has specialized immune cells called Langerhans cells that act as a first alarm. The research indicates that tick saliva reprograms these cells before bacteria like Borrelia enter the picture. The saliva shifts them from an alert fight-ready state into a tolerating stand-down state.  

Research continues into Lyme and other tick borne illnesses.