Infection and Immunity, Ahead of Print.

Abstract Purpose Diagnosis of (European) Lyme neuroborreliosis has been based on clinical presentation, cerebrospinal fluid (CSF) pleocytosis and demonstration of intrathecal borrelial antibody synthesis (ITBAS) to document Borrelia burgdorferi s. l. infection. It is not known if other criteria to document Borrelia infection may contribute to the diagnosis. Methods We compared the sensitivity of three individual criteria (ITBAS, CSF Borrelia culture, and the presence of erythema migrans [EM]) to confirm the diagnosis of early Lyme neuroborreliosis in 280 patients ≥ 15 years of age evaluated at a Lyme borreliosis outpatient clinic in Slovenia. The patients had either radicular pain of new onset or involvement of a cranial nerve but without radicular pain, each in conjunction with CSF pleocytosis. Evaluation was of patients who had each of the three confirmatory criteria assessed, and for whom at least one criterion was positive. Results Analysis of 280 patients, 120 women and 160 men, median age 57 (range 15–84) years, revealed that ITBAS was the most frequently observed positive criterion (85.4%), followed by EM (52.9%), and by a positive CSF Borrelia culture (9.6%). Of the 280 patients, 154 (55%) met only one criterion (43.2% ITBAS only, 10.7% EM only, and 1.1% positive CSF culture only), whereas 42.1% met two criteria. Only 2.9% of patients were positive by all three criteria. Conclusion Although ITBAS was the most frequent criterion for confirmation for Borrelia infection, the presence of EM alone confirmed an additional 10.7% of patients and a positive CSF Borrelia culture alone added another 1.1%. …

Abstract Purpose Diagnosis of (European) Lyme neuroborreliosis has been based on clinical presentation, cerebrospinal fluid (CSF) pleocytosis and demonstration of intrathecal borrelial antibody synthesis (ITBAS) to document Borrelia burgdorferi s. l. infection. It is not known if other criteria to document Borrelia infection may contribute to the diagnosis. Methods We compared the sensitivity of three individual criteria (ITBAS, CSF Borrelia culture, and the presence of erythema migrans [EM]) to confirm the diagnosis of early Lyme neuroborreliosis in 280 patients ≥ 15 years of age evaluated at a Lyme borreliosis outpatient clinic in Slovenia. The patients had either radicular pain of new onset or involvement of a cranial nerve but without radicular pain, each in conjunction with CSF pleocytosis. Evaluation was of patients who had each of the three confirmatory criteria assessed, and for whom at least one criterion was positive. Results Analysis of 280 patients, 120 women and 160 men, median age 57 (range 15–84) years, revealed that ITBAS was the most frequently observed positive criterion (85.4%), followed by EM (52.9%), and by a positive CSF Borrelia culture (9.6%). Of the 280 patients, 154 (55%) met only one criterion (43.2% ITBAS only, 10.7% EM only, and 1.1% positive CSF culture only), whereas 42.1% met two criteria. Only 2.9% of patients were positive by all three criteria. Conclusion Although ITBAS was the most frequent criterion for confirmation for Borrelia infection, the presence of EM alone confirmed an additional 10.7% of patients and a positive CSF Borrelia culture alone added another 1.1%. …

Introduction Ixodes ticks are pivotal in transmitting diseases like Lyme disease and human granulocytic anaplasmosis, caused by Borrelia burgdorferi and Anaplasma phagocytophilum, respectively. These pathogens not only affect humans through single or multiple tick bites but also pose risks to animal hosts, leading to potential coinfections. Despite regional studies indicating significant prevalence, their global coinfection data remain sparse. This study aims to bridge this gap through a systematic review and meta-analysis of B. burgdorferi and A. phagocytophilum coinfections in Ixodes ticks worldwide. Addressing data limitations and study variability, it seeks to provide a nuanced understanding of coinfection patterns, their epidemiological implications and inform targeted prevention strategies. Methods and analysisFollowing Preferred Reporting Items for Systematic Review and Meta-analysis Protocols 2015 guidelines and PROSPERO registration, this study will undertake a thorough database search without constraints on language or publication date, using standardised screening and data extraction protocols. The quality and bias of studies will be evaluated using Joanna Briggs Institute tools. In the statistical analysis phase, conducted in R, we will initially determine the use of fixed or random-effects models based on the assessment of data heterogeneity. This choice will guide the framework for subsequent analyses. Within the selected model’s framework, we will perform subgroup analyses and meta-regression to investigate the effects of various factors, ensuring that each step is tailored to the initial model selection to maintain analytical consistency. Ethics and disseminationAs this study does not involve clinical research or data collection from subjects, ethical approval is not required. We will uphold ethical standards in synthesising and reporting data. Study outcomes will be published in peer-reviewed journals, communicating findings to the scientific community and contributing to the understanding of Ixodes tickborne diseases. PROSPERO registration numberCRD42023449735. …

The predicted high-risk regions are considerably larger than in previous reports. Identification, surveillance, and diagnosis of RFGB infections should be prioritised in high-risk areas, especially within low-income regions.

The predicted high-risk regions are considerably larger than in previous reports. Identification, surveillance, and diagnosis of RFGB infections should be prioritised in high-risk areas, especially within low-income regions.

Infection and Immunity, Ahead of Print.

Infection and Immunity, Ahead of Print.

Abstract Background Genetic variation underly inter-individual variation in host immune responses to infectious diseases, and may affect susceptibility or the course of signs and symptoms. Methods We performed genome-wide association studies in a prospective cohort of 1138 patients with physician-confirmed Lyme borreliosis (LB), the most common tick-borne disease in the Northern hemisphere caused by the bacterium Borrelia burgdorferi sensu lato. Genome-wide variants in LB patients—divided into a discovery and validation cohort—were compared to two healthy cohorts. Additionally, ex vivo monocyte-derived cytokine responses of peripheral blood mononuclear cells to several stimuli including Borrelia burgdorferi were performed in both LB patient and healthy control samples, as were stimulation experiments using mechanistic/mammalian target of rapamycin (mTOR) inhibitors. In addition, for LB patients, anti-Borrelia antibody responses were measured. Finally, in a subset of LB patients, gene expression was analysed using RNA-sequencing data from the ex vivo stimulation experiments. Results We identified a previously unknown genetic variant, rs1061632, that was associated with enhanced LB susceptibility. This polymorphism was an eQTL for KCTD20 and ETV7 genes, and its major risk allele was associated with upregulation of the mTOR pathway and cytokine responses, and lower anti-Borrelia antibody production. In addition, we replicated the recently reported SCGB1D2 locus that was suggested to have a protective effect on B. burgdorferi infection, and associated this locus with higher Borrelia burgdorferi antibody indexes and lower IL-10 responses. Conclusions Susceptibility for LB was associated with higher anti-inflammatory responses and reduced anti-Borrelia antibody production, which in turn may negatively impact bacterial clearance. These findings provide important insights into the immunogenetic susceptibility for LB and may guide future studies on development of preventive or therapeutic measures. Trial registration The LymeProspect study was registered with the International Clinical Trials Registry Platform (NTR4998, registration date 2015–02-13). …

To investigate the short- and long-term risks of atrioventricular block and other cardiac conduction disorders associated with being tested for Borrelia burgdorferi (Bb) antibodies or Bb seropositivity as measures of confounding by indication and Bb infection, respectively.

Infection and Immunity, Ahead of Print.

In a nationwide, matched cohort study, we aimed to investigate risks of hematologic cancers among individuals tested for Borrelia burgdorferi (Bb) antibodies, and among serum Bb seropositive individuals.

by Andrea M. Kirby, Ellis P. Evans, Samantha J. Bishop, Vett K. Lloyd Tick populations are dependent on a complex interplay of abiotic and biotic influences, many of which are influenced by anthropic factors including climate change. Dermacentor variabilis, the wood tick or American dog tick, is a hardy tick species that feeds from a wide range of mammals and birds that can transmit pathogens of medical and agricultural importance. Significant range expansion across North America has been occurring over the past decades;this study documents northwards range expansion in the Canadian Maritime provinces. Tick recoveries from passive surveillance between 2012 and 2021 were examined to assess northward population expansion through Atlantic Canada. At the beginning of this period, D. variabilis was abundant in the most southerly province, Nova Scotia, but was not considered established in the province to the north, New Brunswick. During the 10-year span covered by this study, an increasing number of locally acquired ticks were recovered in discrete foci, suggesting small established or establishing populations in southern and coastal New Brunswick. The pattern of population establishment follows the climate-driven establishment pattern of Ixodes scapularis to some extent but there is also evidence of successful seeding of disjunct populations in areas identified as sub-optimal for tick populations. Dogs were the most common host from which these ticks were recovered, which raises the possibility of human activity, via movement of companion animals, having a significant role in establishing new populations of this species. Dermacentor variabilis is a vector of several pathogens of medical and agricultural importance but is not considered to be a competent vector for Borrelia burgdorferi, the etiological agent of Lyme disease; our molecular analysis of a subset of D. variabilis for both B. burgdorferi and B. miyamotoi did not confirm any with Borrelia. This study spans the initial establishment of this tick species and documents the pattern of introduction, providing a relatively unique opportunity to examine the first stages of range expansion of a tick species.

by Samir Mechai, Heather Coatsworth, Nicholas H. Ogden The outer surface protein C (OspC) of the agent of Lyme disease, Borrelia burgdorferi sensu stricto, is a major lipoprotein surface-expressed during early-phase human infections. Antibodies to OspC are used in serological diagnoses. This study explored the hypothesis that serological test sensitivity decreases as genetic similarity of ospC major groups (MGs) of infecting strains, and ospC A (the MG in the strain B31 used to prepare antigen for serodiagnosis assays) decreases. We used a previously published microarray dataset to compare serological reactivity to ospC A (measured as pixel intensity) versus reactivity to 22 other ospC MGs, within a population of 55 patients diagnosed by two-tier serological testing using B. burgdorferi s.s. strain B31 as antigen, in which the ospC MG is OspC A. The difference in reactivity of sera to ospC A and reactivity to each of the other 22 ospC MGs (termed ‘reactivity difference’) was the outcome variable in regression analysis in which genetic distance of the ospC MGs from ospC A was the explanatory variable. Genetic distance was computed for the whole ospC sequence, and 9 subsections, from Neighbour Joining phylogenetic trees of the 23 ospC MGs. Regression analysis was conducted using genetic distance for the full ospC sequence, and the subsections individually. There was a significant association between the reactivity difference and genetic distance of ospC MGs from ospC A: increased genetic distance reduced reactivity to OspC A. No single ospC subsection sequence fully explained the relationship between genetic distance and reactivity difference. An analysis of single nucleotide polymorphisms supported a biological explanation via specific amino acid modifications likely to change protein binding affinity. This adds support to the hypothesis that genetic diversity of B. burgdorferi s.s. (here specifically OspC) may impact serological diagnostic test performance. Further prospective studies are necessary to explore the clinical implications of these findings.

Volume 14, Issue 1, December 2023 .

Lyme borreliosis (LB) is the most common tick-transmitted infection on the northern hemisphere and is caused by bacteria in the Borrelia burgdorferi sensu lato (Bbsl)-complex. The diagnosis is partially based on serology and clinicians often take follow-up serum samples to look for seroconversion or an increase in IgG-antibody levels. In this registry-based study, we proposed a method for determining actual changes in IgG and examined antibody reactivity and decay.

Ongoing surveillance will improve understanding of the incidence, clinical severity, and public health role of this emerging disease. …

by Dashdavaa Ganbold, Bayarsaikhan Uudus, Naranbat Nyamdavaa, Yeruult Chultemsuren, Amarbayasgalan Zagd, Mungunzaya Tangad, Agarzandan Bayarmaa, Rolomjav Lkunrev, Uyanga Baasandagva, Tsogbadrakh Nyamdorj, Myadagsuren Narankhajid Borrelia burgdorferi sensu lato and Rickettsia spp. are worldwide causes of tick-borne infections. We aimed to estimate the seroprevalence of immunoglobulin G (IgG) antibodies against different tick-borne diseases (TBDs) and determine risk factors among Mongolians from 2016 to 2020. Blood samples were obtained from voluntary participants with a history of suspected tick bite who visited our hospital, and IgG antibodies against Rickettsia and Borrelia were detected using enzyme-linked immunosorbent assay (ELISA). The IgG antibody seropositivity rate against Rickettsia was 21.8% (1032/4724), while 3.4% (162/4724) of participants tested positive for serum IgG antibodies against Borrelia by ELISA.Binary logistic regression analysis was performed to evaluate risk factors for tick-borne rickettsiosis (TBR) and tick-borne borreliosis (TBB) using IgG serum sample. Age, occupation, and residence were significantly associated with these diseases; however, sex did not show any significant association. Seroprevalence was significantly higher among herders (40.6%, 95% confidence interval [CI]: 35.5–45.8; odds ratio [OR] 0.61; P < 0.001) and students (32.8%, 95% CI: 30.2–35.4; OR 0.75; P < 0.001) than among individuals with other occupations. The 25–29 age group had a slightly higher seroprevalence (35.1%, 95% CI: 28.1–42.6; OR 0.61; P < 0.006) than those in other age groups. Province was a stronger predictor of TBR than occupation and age group. In univariate subgroup analysis by age group, occupation, and residence were significantly associated with TBR seroprevalence, whereas age and province were associated with TBB seroprevalence. Thus, risk factors for TBD include residence, occupation, and age group. This study was conducted using samples from all Mongolian provinces and the capital city, and the risk factors and prevalence of Rickettsia and Borreliaare highlighted.

by Ivar Tjernberg, Malin Lager, Guro Furset Jensen, Randi Eikeland, Dag Nyman, Lars Brudin, Anna J. Henningsson Objectives Lyme serology does not readily discriminate an active Lyme borreliosis (LB) from a previous Borrelia infection or exposure. Here, we aimed to investigate a large number of immunological protein biomarkers to search for an immunological pattern typical for active LB, in contrast to patterns found in healthy blood donors, a proportion of whom were previously exposed to Borrelia. Methods Serum samples from well-characterised adult patients with ongoing LB and healthy blood donors were included and investigated using a proximity extension assay (provided by Olink®) by which 92 different immune response-related human protein biomarkers were analysed simultaneously. Results In total, 52 LB patients and 75 healthy blood donors were included. The blood donors represented both previously Borrelia exposed (n = 34) and not exposed (n = 41) based on anti-Borrelia antibody status. Ten of the examined 92 proteins differed between patients and blood donors and were chosen for further logistic regression (p…

Lyme borreliosis is the most prevalent vector-borne disease in Europe and North America [1]; an estimated ≈232,000 cases in Western Europe [2] and ≈476,000 cases in the US [3] are diagnosed per year and erythema migrans is its most frequent clinical presentation, occurring in ≥80% of cases [1,4]. In solitary erythema migrans (SEM), the skin manifestation remains localised to the site of inoculation of borreliae, whereas multiple erythema migrans (MEM) represent hematogenous dissemination of borreliae, which may occur in 13.4% to 27% of US cases [5‒7] and less frequently (up to 7%) in Europe [4,6].

Abstract Background Lyme neuroborreliosis (LNB), due to infection of the nervous system by the spirochete Borrelia burgdorferi, occurs in 15% of Lyme disease cases. However, neurovascular involvement is uncommon, especially recurrent stroke related to cerebral vasculitis in the absence of CSF pleocytosis. Case presentation We report the case of a 58-year-old man without any medical history who exhibited recurrent strokes in the same vascular territory (left internal carotid). Multiple biological screening, neuroimaging methods, and cardiovascular examinations failed to provide a diagnosis and treatment that could have prevented recurrences. Finally, B. burgdorferi sensu lato serology testing in blood and cerebrospinal fluid enabled diagnosis of LNB, in relation to a cerebral vasculitis. The patient experienced no further stroke after four weeks of doxycycline treatment. Conclusion B. burgdorferi central nervous system infection must be considered in case of unexplained recurrent and/or multiple strokes, especially if cerebral vasculitis is suspected or demonstrated on neuroimaging. …

Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 108 Issue: 5 Pages: 968-976 …

Dispatch - Borrelia miyamotoi Infection in Immunocompromised Man, California, USA, 2021…

Infection and Immunity, Ahead of Print.

Human cases of TBDs in Europe have increased steadily over the past decades [1]. Well-known pathogens such as Borrelia burgdorferi sensu lato and tick-borne encephalitis virus (TBEV) have expanded their distribution, while several others, such as Borrelia miyamotoi, have only recently been identified as human pathogens [2–4]. Although this upsurge can in part be explained by improved medical diagnostics and awareness, human demographics, and human behavior, it is also a consequence of environmental and climatic changes [5–7].

Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 108 Issue: 3 Pages: 510-512 …

Infection and Immunity, Ahead of Print.