Ticks harbor a variety of infectious pathogens besides Borrelia burgdorferi (Lyme pathogen). Pathogens such as bacteria, viruses, and parasites are commonly found within a tick’s midgut and salivary glands. During a bite, the tick can infect someone with one or more of these pathogens.
Any tick-borne infection other than Lyme disease is usually referred to as a “co-infection.” Co-infections can be acquired with or without Lyme disease in one bite, or through multiple tick bites over time. Polymicrobial infections can lead to an increased severity of certain symptoms, as well as symptoms that persist after proper treatment.
Many of the symptoms of Lyme disease and co-infections overlap. For this reason, they can be challenging to diagnose. Luckily there are some hallmark symptoms for each infection that help us begin the important detective work of identifying and treating each tick-borne disease.