Spirochetal diseases, collectively, are an important global health concern due to their ubiquitous distribution, profound clinical outcomes, and significant socioeconomic impacts. The major genera of medically relevant spirochetes include Treponema (syphilis and other diseases), Leptospira (leptospirosis), and Borrelia (Lyme disease and relapsing fever). Despite vast differences by which humans acquire these infections, the spirochetes broadly share the characteristics of possessing unique mechanisms by which to circumvent host responses, establish invasive and chronic infections, and elicit significant multi-stage clinical manifestations affecting multiple body systems.

Aside from the virulence mechanisms, a key determinant of spirochetal disease commonly is the host response. For example, Treponema pallidum subsp. pallidum lacks an array of exposed pathogen-associated molecular patterns sufficient to elicit an effective innate response to it. In addition, a high level of human pathogenic leptospires in the blood induces robust innate effectors that can lead to life-threatening conditions. Moreover, inflammatory T cells activated in response to, in particular Borrelia burgdorferi sensu stricto are associated with persistent Lyme arthritis that, in some patients, progresses to an autoimmune condition. The sequences of immune events launched in response to these respective pathogens are as intriguing as they are disparate. However, despite our current knowledge of spirochete-host interactions, there still is much to learn about how these microbes evade the immune response in several ways, how host defenses are elicited to them, and how the host response, including overactive or dysregulated responses, may contribute to pathology.

In this Research Topic, we welcome submissions of research articles and review and opinion pieces related to the host response to spirochete infections. Topics of interest include, but are not limited to:

- Immune evasion.
- Innate and adaptive responses.
- Immune dysregulation/immunopathology
- Vaccines
- Diagnostic tests, novel therapeutics, and novel animal models.

These studies will address critical gaps in our understanding of these globally significant diseases.

Are you interested in contributing a manuscript to this Research Topic?

Host response to spirochete infections