Search Results (4)

Background:Bartonella quintana is a body-louse-borne bacterium. Canadian B. quintana 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 B. quintana in Canada. Methods: 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 B. quintana in Canada. Results: Thirty-three individuals with qPCR-positive B. quintana were documented in seven provinces and one territory. The number of cases increased over time (p-value = 0.005), with the greatest number of cases being reported in 2022 and 2023. The percent positivity for the B. quintana qPCR performed at the NML increased over time (p-value = 0.036). The median immunoglobulin G titer demonstrated a sustained increase starting in 2017. The systematic review identified fourteen individuals with qPCR-positive B. quintana (none had a qPCR performed at the NML) and seven probable cases of B. quintana disease. Four of these twenty-one individuals from the systematic review died (19%). All fatalities were attributed to endocarditis. Conclusions: The detection of B. quintana disease in seven provinces and one territory suggests that B. quintana has a national distribution. B. quintana disease is increasingly diagnosed in Canada, indicating ongoing transmission across geographic settings. Full article

Human lice are the only hematophagous ectoparasites specific to human hosts. They transmit epidemic typhus, trench fever and relapsing fever, diseases which have already caused millions of deaths worldwide. In order to further investigate lice vectorial capacities, laboratory-controlled live lice colonies are essential. Previously developed lice-rearing methods significantly advanced research on louse-borne diseases and louse biology. In this study, we aimed to develop a rearing technique for the Orlando (Or) strain of body lice on an artificial membrane. We tested two systems, namely the Hemotek feeding system and a Petri dish with the lice being fed through a Parafilm membrane. Lice longevity and development were drastically affected by the blood anticoagulant. Additionally, heparinised human blood on a Petri dish was the best candidate when compared to the control group (reared on a rabbit). Therefore, this strategy was applied to 500 lice. Development into adulthood was recorded after 21 days (17 days for the rabbits), and 52 eggs were deposited (240 for the rabbits). In this study, we were able to maintain one generation of body lice on an artificial membrane with comparable feeding and longevity rates to those fed on live rabbits. However, lice fecundity decreased on the artificial membrane. In vitro lice-rearing experiments will enable pathogen infection assays and pesticide bioassays to be carried out in accordance with animal welfare requirements. Full article

Trench fever, caused by Bartonella quintana, is recognized as a re-emerging and neglected disease. Rapid and sensitive detection approaches are urgently required to monitor and help control B. quintana infections. Here, loop-mediated isothermal amplification (LAMP), which amplifies target DNA at a fixed temperature with high sensitivity, specificity and rapidity, was employed to detect B. quintana. Thirty-six strains, including 10 B. quintana, 13 other Bartonella spp., and 13 other common pathogens, were applied to verify and evaluate the LAMP assay. The specificity of the LAMP assay was 100%, and the limit of detection was 125 fg/reaction. The LAMP assay was compared with qPCR in the examination of 100 rhesus and 20 rhesus-feeder blood samples; the diagnostic accuracy was found to be 100% when LAMP was compared to qPCR, but the LAMP assay was significantly more sensitive (p < 0.05). Thus, LAMP methodology is a useful for diagnosis of trench fever in humans and primates, especially in low-resource settings, because of its rapid, sensitive detection that does not require sophisticated equipment. Full article

The morbidity and mortality associated with infective endocarditis can be significantly reduced by early diagnosis and initiation of effective therapy. Due to the often nonspecific prosaic symptoms associated with infective endocarditis, patients are likely to seek initial medical care from their primary care physicians. The authors present the history of a patient suffering from indolent prolonged illness with moderate fever who developed painless macrohematuria and triple valve endocarditis with Bartonella quintana. This pathogen is a gram-negative bacterium responsible for the epidemic louse-borne trench-fever seen in Europe during World War I and particularly seen as an infectious agent in HIV patients. Full article