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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.

Infection and Immunity, Ahead of Print.

Abstract Background Lyme borreliosis (LB) is the most common tick-borne infectious disease in the northern hemisphere. The diagnosis of LB is usually made by clinical symptoms and subsequently supported by serology. In Europe, a two-step testing consisting of an enzyme-linked immunosorbent assay (ELISA) and an immunoblot is recommended. However, due to the low sensitivity of the currently available tests, antibody detection is sometimes inaccurate, especially in the early phase of infection, leading to underdiagnoses. Methods To improve upon Borrelia diagnostics, we developed a multiplex Borrelia immunoassay (Borrelia multiplex), which utilizes the new INTELLIFLEX platform, enabling the simultaneous dual detection of IgG and IgM antibodies, saving further time and reducing the biosample material requirement. In order to enable correct classification, the Borrelia multiplex contains eight antigens from the five human pathogenic Borrelia species known in Europe. Six antigens are known to mainly induce an IgG response and two antigens are predominant for an IgM response. Results To validate the assay, we compared the Borrelia multiplex to a commercial bead-based immunoassay resulting in an overall assay sensitivity of 93.7% (95% CI 84.8–97.5%) and a specificity of 96.5% (95%CI 93.5–98.1%). To confirm the calculated sensitivity and specificity, a comparison with a conventional 2-step diagnostics was performed. With this comparison, we obtained a sensitivity of 95.2% (95% CI 84.2–99.2%) and a specificity of 93.0% (95% CI 90.6–94.7%). Conclusion Borrelia multiplex is a highly reproducible cost- and time-effective assay that enables the profiling of antibodies against several individual antigens simultaneously. …

Clinical Microbiology Reviews, Ahead of Print. …

Infection and Immunity, Ahead of Print. …

Lyme borreliosis, caused by members of the Borrelia burgdorferi sensu lato (Bbsl) complex, is the most common vector-borne disease in Europe and the USA, with over 600 000 cases estimated to occur annually in these regions since 2010.1,2 Given this impressive global burden, it is remarkable that there are still substantial diagnostic gaps for Lyme borreliosis, including the absence of reliable assays for acute infection, difficulty in differentiating past disease from current disease, and an inability to monitor treatment response.

by Samuel D. Mason, Samuel C. R. Sherratt, Samantha M. Kruguer, Michael Muthersbaugh, Jonathan P. Harris, Wayne C. Gatlin, Justin D. Topp, Gregory S. Keller

Habitat fragmentation and heterogeneity transform otherwise contiguous tracks of forest into smaller patches in the northeastern U.S. and likely impact abundances, movement patterns, and disease transmission pathways for small-mammal communities at multiple scales. We sought to determine the structure of a small-mammal community in terms of mammal abundance and infection prevalence of Borrelia burgdorferi sensu stricto (s.s.), Anaplasma phagocytophilum, and Babesia microti within a fragmented landscape in Essex County, Massachusetts, USA. We studied communities at multiple spatial scales, including vegetation, edge type, and landscape (including 200-m, 500-m, and 1000-m radii) scales. A total of 16 study sites were chosen to represent four edge types: interior forest, pasture edge, natural edge, and residential edge. At each site, we trapped small mammals and conducted vegetation surveys and GIS analysis. Upon capture, a tissue sample was collected to analyze for presence of pathogens. Northern short-tailed shrew (Blarina brevicauda) abundance did not differ based on edge type, whereas abundance of the white-footed mouse (Peromyscus leucopus) was greatest at pasture edges, although the relationship was relatively weak. White-footed mouse abundance was negatively associated with amount of forested area within a 500-m radius, whereas northern short-tailed shrew abundance demonstrated a positive relationship with fragmentation indices at the 200-m radius. White-footed mice captured at interior-forest habitat were more likely be infected with B. burgdorferi (s.s.) than individuals from edge habitat. Greater prevalence of B. burgdorferi infection of white-footed mice in forest interiors compared to edge habitats counters previous studies. Reasons for this and implications are discussed.

Clinical guidelines disagree on the diagnostic usefulness of Borrelia burgdorferi (Bb) serum antibodies (serum-Bb) in investigation of Lyme neuroborreliosis (LNB). We investigated the association between serum-Bb and Bb intrathecal antibody index (Bb-AI) and rates of seroconversion and seroreversion after LNB.

by Patrick Pearson, Olivia Skaltsis, Chu-Yuan Luo, Guang Xu, Zachary Oppler, Dustin Brisson, Stephen M. Rich

Borrelia burgdorferi is an important tickborne human pathogen comprising several strains based on nucleotide sequence of the outer surface protein C (ospC) gene. Detection and characterization of different ospC genotypes is vital for research on B. burgdorferi and the risk it poses to humans. Here we present a novel, multiplex assay based on Luminex xMAP technology for the detection of B. burgdorferi ospC genotypes. The assay has five major steps: amplification of the ospC gene, hydrolyzation of surplus primers and nucleotides, incorporation of biotinylated nucleotides into the template DNA, hybridization to Luminex microspheres, and detection of fluorescent signals corresponding to each ospC genotype. We validated the protocol by comparing results obtained from our method against results from an established ospC genotyping method. This protocol can be used for the characterization of ospC genotypes in B. burgdorferi infected ticks, reservoir hosts, and/or clinical samples.

Case report…

Infection and Immunity, Ahead of Print. …

by Ariane Dumas, Catherine Bouchard, Antonia Dibernardo, Pierre Drapeau, L. Robbin Lindsay, Nicholas H. Ogden, Patrick A. Leighton

Ixodes scapularis ticks are expanding their range in parts of northeastern North America, bringing with them pathogens of public health concern. While rodents like the white-footed mouse, Peromyscus leucopus, are considered the primary reservoir of many emerging tick-borne pathogens, the contribution of birds, as alternative hosts and reservoirs, to local transmission cycles has not yet been firmly established. From 2016 to 2018, we collected host-seeking ticks and examined rodent and bird hosts for ticks at 48 sites in a park where blacklegged ticks are established in Quebec, Canada, in order to characterize the distribution of pathogens in ticks and mammalian and avian hosts. We found nearly one third of captured birds (n = 849) and 70% of small mammals (n = 694) were infested with I. scapularis. Five bird and three mammal species transmitted Borrelia burgdorferi to feeding larvae (n larvae tested = 2257) and we estimated that about one fifth of the B. burgdorferi-infected questing nymphs in the park acquired their infection from birds, the remaining being attributable to mice. Ground-foraging bird species were more parasitized than other birds, and species that inhabited open habitat were more frequently infested and were more likely to transmit B. burgdorferi to larval ticks feeding upon them. Female birds were more likely to transmit infection than males, without age differentiation, whereas in mice, adult males were more likely to transmit infection than juveniles and females. We also detected Borrelia miyamotoi in larvae collected from birds, and Anaplasma phagocytophilum from a larva collected from a white-footed mouse. This study highlights the importance of characterising the reservoir potential of alternative reservoir hosts and to quantify their contribution to transmission dynamics in different species assemblages. This information is key to identifying the most effective host-targeted risk mitigation actions.

Infection and Immunity, Ahead of Print. …

Infection and Immunity, <a href='https://journals.asm.org/toc/iai/0/ja'>Volume 0, Issue ja</a>, -Not available-. …

Journal Name: The American Journal of Tropical Medicine and HygieneVolume: 106Issue: 1Pages: 45-46

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AbstractBackgroundQuantiFERON enzyme-linked immunosorbent assay (ELISA; Qiagen) with Borrelia burgdorferi peptide antigens was previously shown to reliably detect interferon-γ (IFN-γ) in blood samples from adult patients with early Lyme disease and the response disappeared rapidly after treatment. We evaluated the response before and after appropriate antibiotic therapy in adolescent and adult subjects with more diverse stages of the illness.MethodsBlood was obtained from patients with clinician-identified Lyme disease with constitutional complaints, erythema migrans, nerve palsy, cardiac abnormality, or arthritis before (n = 68) and 6 weeks (n = 46) and 6 months (n = 45) after therapy. The sera were tested for Lyme disease by standard 2-tiered testing (STTT) and anti–C6 antibodies by ELISA and the levels of IFN-γ in the blood samples were detected by QuantiFERON ELISA.ResultsA positive STTT result supported the clinical diagnosis of 37 (54%) subjects and anti-C6 antibodies were detected in 45 (66%) subjects, including 36 (97%) STTT-positive subjects, and the responses often persisted or expanded after antibiotic therapy. IFN-γ was detected in 49 (72%) subjects prior to treatment and the response most often significantly decreased 6 weeks (P = .007) or 6 months (P = .001) after treatment.ConclusionsThe QuantiFERON ELISA reliably detected IFN-γ in blood samples from adult and adolescent patients with varying stages of Lyme disease and the response disappeared rapidly after treatment. Additional studies to more critically evaluate clinical utility as a laboratory test for diagnosis and confirmation of effective therapy are warranted.

Abstract

Background

Erythema migrans (EM) is the most common manifestation of Lyme borreliosis. Here, we examined EM patients in Norwegian general practice to find the proportion exposed to tick-transmitted microorganisms other than Borrelia, and the impact of co-infection on the clinical manifestations and disease duration.

Methods

Skin biopsies from 139/188 EM patients were analyzed using PCR for Neoehrlichia mikurensis, Rickettsia spp., Anaplasma phagocytophilum and Babesia spp. Follow-up sera from 135/188 patients were analyzed for spotted fever group (SFG) Rickettsia, A. phagocytophilum and Babesia microti antibodies, and tested with PCR if positive. Day 0 sera from patients with fever (8/188) or EM duration of ≥ 21 days (69/188) were analyzed, using PCR, for A. phagocytophilum, Rickettsia spp., Babesia spp. and N. mikurensis. Day 14 sera were tested for TBEV IgG.

Results

We detected no microorganisms in the skin biopsies nor in the sera of patients with fever or prolonged EM duration. Serological signs of exposure against SFG Rickettsia and A. phagocytophilum were detected in 11/135 and 8/135, respectively. Three patients exhibited both SFG Rickettsia and A. phagocytophilum antibodies, albeit negative PCR. No antibodies were detected against B. microti. 2/187 had TBEV antibodies without prior immunization. There was no significant increase in clinical symptoms or disease duration in patients with possible co-infection.

Conclusions

Co-infection with N. mikurensis, A. phagocytophilum, SFG Rickettsia, Babesia spp. and TBEV is uncommon in Norwegian EM patients. Despite detecting antibodies against SFG Rickettsia and A. phagocytophilum in some patients, no clinical implications could be demonstrated.

AbstractBackgroundLyme neuroborreliosis peripheral facial palsy (LNB PFP) and idiopathic PFP, Bell’s palsy (BP), are the most common causes of facial palsy in borrelia-endemic areas and are clinically similar. Early treatment with corticosteroids has been shown to be effective in Bell’s palsy, and antibiotics improve the outcome in LNB. However, there is a lack of knowledge on how the addition of corticosteroids to standard antibiotic treatment affects the outcome in LNB PFP.MethodsThis prospective, open trial with historical controls was conducted at 2 large hospitals in western Sweden between 2011 and 2018. Adults who presented with LNB PFP were included in the study group and were treated with oral doxycycline 200 mg twice daily for 10 days and prednisolone 60 mg once daily for 5 days, then tapered over 5 days. The historical controls were adult patients with LNB PFP included in previous studies and treated with oral doxycycline. Both groups underwent a follow-up lumbar puncture and were followed until complete recovery or for 12 months.ResultsFifty-seven patients were included, 27 in the study group and 30 in the control group. Two patients (7%) in the study group and 6 patients (20%) in the control group suffered from sequelae at the end follow-up. There was no statistically significant difference between the groups, either in the proportion of patients with sequelae or in the decline in cerebrospinal fluid mononuclear cell count.ConclusionsAdjunctive corticosteroids neither improve nor impair the outcome for patients with LNB PFP treated with doxycycline.

by Richard Porwancher, Lisa Landsberg

Multiple different recombinant and peptide antigens are now available for serodiagnosis of Lyme disease (LD), but optimizing test utilization remains challenging. Since 1995 the Centers for Disease Control and Prevention (CDC) has recommended a 2-tiered serologic approach consisting of a first-tier whole-cell enzyme immunoassay (EIA) for polyvalent antibodies to Borrelia burgdorferi followed by confirmation of positive or equivocal results by IgG and IgM immunoblots [standard 2-tiered (STT) approach]. Newer modified 2-tiered (MTT) approaches employ a second-tier EIA to detect antibodies to B. burgdorferi rather than immunoblotting. We applied modern bioinformatic techniques to a large public database of recombinant and peptide antigen-based immunoassays to improve testing strategy. A retrospective CDC collection of 280 LD samples and 559 controls had been tested using the STT approach as well as kinetic-EIAs for VlsE1-IgG, C6-IgG, VlsE1-IgM, and pepC10-IgM antibodies. When used individually, the cutoff for each kinetic-EIA was set to generate 99% specificity. Utilizing logistic-likelihood regression analysis and receiver operating characteristic (ROC) techniques we determined that VlsE1-IgG, C6-IgG, and pepC10-IgM antibodies each contributed significant diagnostic information; a single-tier diagnostic score (DS) was generated for each sample using a weighted linear combination of antibody levels to these 3 antigens. DS performance was then compared to the STT and to MTT models employing different combinations of kinetic-EIAs. After setting the DS cutoff to match STT specificity (99%), the DS was 22.5% more sensitive than the STT for early-acute-phase disease (95% CI: 11.8% to 32.2%), 16.0% more sensitive for early-convalescent-phase disease (95% CI: 7.2% to 24.7%), and equivalent for detection of disseminated infection. The DS was also significantly more sensitive for early-acute-phase LD than MTT models whose specificity met or exceeded 99%. Prospective validation of this single-tier diagnostic score for Lyme disease will require larger studies using a broader range of potential cross-reacting conditions.

A previously healthy 42-year-old male from the upper Midwestern United States presented with a 1-day history of fever, fatigue, headache, myalgias, and arthralgias. He reported removing a “wood tick” the day of admission. His temperature was 38.4°C. No swollen joints, rash, or neurological abnormalities were noted on physical examination.

Infection and Immunity, <a href="https://journals.asm.org/toc/iai/0/ja">Volume 0, Issue ja</a>, -Not available-.

Infection and Immunity, <a href="https://journals.asm.org/toc/iai/89/6">Volume 89, Issue 6</a>, May 2021.

Infection and Immunity, <a href="https://journals.asm.org/toc/iai/0/ja">Volume 0, Issue ja</a>, -Not available-.