Infection in Canada: A Retrospective Laboratory Study and Systematic Review of the Literature.

is a body-louse-borne bacterium. Canadian disease has been reported primarily in populations experiencing homelessness and in Indigenous communities with limited access to water. We sought to understand the epidemiology of in Canada. This study combined an analysis of laboratory data from Canada's National Microbiology Laboratory (NML) with a systematic review of the literature. Laboratory data included quantitative polymerase chain reaction (qPCR) cycle threshold values and indirect immunofluorescent antibody titers with the year and province of the sample acquisition. For the systematic review, we searched PubMed, Scopus, Embase, and Web of Science for articles published before 15 July 2024, with terms related to in Canada. Thirty-three individuals with qPCR-positive were documented in seven provinces and one territory. The number of cases increased over time (-value = 0.005), with the greatest number of cases being reported in 2022 and 2023. The percent positivity for the qPCR performed at the NML increased over time (-value = 0.036). The median immunoglobulin G titer demonstrated a sustained increase starting in 2017. The systematic review identified fourteen individuals with qPCR-positive (none had a qPCR performed at the NML) and seven probable cases of disease. Four of these twenty-one individuals from the systematic review died (19%). All fatalities were attributed to endocarditis. : The detection of disease in seven provinces and one territory suggests that has a national distribution. disease is increasingly diagnosed in Canada, indicating ongoing transmission across geographic settings.