Why, Immunologically, Housing-Related Fungi and Endotoxins (and Other Chronic Pro-Inflammatory Stressors) Risk Latent Tuberculosis Reactivation, Severe Asthma, and Translocating and Invasive Infections in Indigenous Communities in Canada

Abstract

Type 1/M1/T_H1 and type 3/M1/T_H17 pro-inflammatory switches are risks for latent Mycobacterium tuberculosis (Mtb) reactivation and ongoing infection transmission. This paper considers the heavy toll of reactivation risk in Indigenous communities in Canada and the chronic, everyday pro-inflammatory stressors connected with type 3/M1/T_H17 immune switching, including household fungal and endotoxin exposures that fuel reactivation risk. The paper argues that regular or chronic pro-inflammatory stressors are risks not only for latent Mtb reactivation and ongoing transmission, but also, via compromised type 4/M2/T_H22 mucosal barrier protections, severe asthma and translocated, possibly invasive, bacterial, viral, and fungal infections. Individual and community efforts to reduce chronic pro-inflammatory stressors are important, but as the immunological, switch-inducing rationale suggests, unless chronic pro-inflammatory risks associated with housing are mediated, tuberculosis reactivation and other health risks will likely persist.