Lyme arthritis: an epidemic of oligoarticular arthritis in children and adults in three connecticut communities

Perspective: Incidence of Clinician-Diagnosed Lyme Disease in Manitoba, Canada 2009-2018

Introduction: Lyme disease (LD) surveillance yields useful information to monitor the disease trends and spatial distribution. However, due to several factors, the Manitoba Health surveillance system, as with other systems, could be subject to underreporting. Objectives: To estimate the number and incidence of clinician-diagnosed LD over the study period in Manitoba, describe the epidemiology of clinician-diagnosed LD, and compare the findings with Manitoba Health LD surveillance data during the same period to estimate the extent of underreporting. Methods: A retrospective analysis of administrative health data was performed to calculate the number and incidence of clinician-diagnosed LD from 2009 to 2018 in Manitoba and describe the epidemiological characteristics using the International Classification of Diseases, Tenth and Ninth Revision (ICD-10-CA and ICD-9-CM) codes, and antimicrobial drug prescriptions. Conclusion: Of the 1,629,698 registrants within the Manitoba Health Insurance Registry followed over 10 years, 1658 LD events were identified. Most of the cases occurred from May to July and corresponded to the peak activity of the nymphal stage of the blacklegged tick in the province. LD events presented a bimodal distribution with a peak in children between 5 and 9 years of age for both sexes, and a peak in adults from 65 to 84 and from 50 to 74, respectively, for males and females. We estimated that an average of 165 LD events occurred annually in Manitoba (mean annual incidence of 10.17 per 100,000 population), compared with 30 cases per year reported in the surveillance system; therefore, the LD surveillance yields an important underreporting.

Proposed Immunopathogenetic Mechanisms Underlying Lyme Arthritis

ABSTRACT

Lyme disease is commonly associated with musculoskeletal features, inflammatory and noninflammatory. The precise pathogenesis of the clinical features of this infection are complex and often multiple. A better understanding of how Borrelia burgdorferi causes these musculoskeletal manifestations is necessary in order to determine the proper treatment and eschew that which is unlikely to work, often associated with toxicities. The following review seeks to summarize the various immunopathogenic mechanisms that may cause these features of Lyme disease and suggests a series of approaches based on the most likely underlying mechanism(s).

Differentiating Lyme arthritis: a case-based review

The incidence or prevalence of Lyme arthritis (LA) in Denmark is unknown and assumed very low. No published cases of polymerase chain reaction (PCR)-confirmed LA from Denmark exist. Clinically, LA does not differ from other rheumatic oligoarthritic disorders posing a differential diagnostic challenge. To review the incidence and prevalence of LA to our knowledge and to present a case series of PCR-confirmed LA cases from Denmark. We conducted a systematic literature review via MEDLINE and EMBASE to explore incidence and prevalence rates of LA. Additionally, we present six cases of patients diagnosed with LA in Denmark. Our literature review identified 23 studies reporting prevalence or incidence, yet only ten studies provided estimates ranging from 1.1 to 280/100.000 in the general population. Our case series identified six patients with LA from a localized region in Southern Denmark; all confirmed by Borrelia-specific real-time PCR from synovial fluid. The diagnostic delay was up to 38 months. All patients except one had a history of previous tick bites; none had erythema migrans lesions. All presented with recurrent arthritis in the knee joint, and two had arthritis in the wrist. The literature review showed an incidence of LA ranging from 1.1 to 15.8 per 100.000 in Europe. Our case series suggests a potentially higher prevalence of LA in Denmark than previously believed. Lack of tick exposure history, antibody assessments and test of Borrelia burgdorferi sensu lato DNA in synovial fluid might lead to misdiagnosed cases potentially explaining the assumed low incidence of LA in Denmark.

Hitchhiker's Guide to Borrelia burgdorferi

Don't Panic. In the nearly 50 years since the discovery of Lyme disease, Borrelia burgdorferi has emerged as an unlikely workhorse of microbiology. Interest in studying host-pathogen interactions fueled significant progress in making the fastidious microbe approachable in laboratory settings, including the development of culture methods, animal models, and genetic tools. By developing these systems, insight has been gained into how the microbe is able to survive its enzootic cycle and cause human disease. Here, we discuss the discovery of B. burgdorferi and its development as a model organism before diving into the critical lessons we have learned about B. burgdorferi biology at pivotal stages of its lifecycle: gene expression changes during the tick blood meal, colonization of a new vertebrate host, and developing a long-lasting infection in that vertebrate until a new tick feeds. Our goal is to highlight the advancements that have facilitated B. burgdorferi research and identify gaps in our current understanding of the microbe.

Wider recognition and greater understanding of postinfectious, antibiotic-refractory Lyme arthritis

Lyme disease, caused by Borrelia burgdorferi (Bb), can progress to Lyme arthritis (LA). While most patients with LA respond successfully to antibiotic therapy, a small percentage fail to improve, a condition known as antibiotic-refractory Lyme arthritis (ARLA). While T cell responses are known to drive ARLA, molecular mechanisms for ARLA remain unknown. In this issue of the JCI, Dirks et al. isolated disease-specific Th cells from patients with ARLA residing in Germany. A distinct TCR-β motif distinguished ARLA from other rheumatic diseases. Notably, the TCR-β motif was linked predominantly to HLA-DRB1*11 or 13 alleles, which differed from alleles in patients from North America. It also mapped primarily to T peripheral helper (Tph) cells, as opposed to classical Th1 cells. These findings provide a roadmap explaining how T cell responses necessary for control of an infection can, despite antibiotic therapy, drive a disadvantageous T cell response, resulting in a postinfectious, inflammatory arthritis.

Lyme Disease Surveillance and Epidemiology in the United States: A Historical Perspective

In the 40 years since Steere and colleagues first described Lyme disease, the illness has increased in incidence and distribution to become the most common vector-borne disease in the United States. Public health officials have developed, implemented, and revised surveillance systems to describe and monitor the condition. Much has been learned about the epidemiology of the illness, despite practical and logistical constraints that have encumbered the collection and interpretation of surveillance data. Future development of automated data collection from electronic health records as a source of surveillance and clinical information will address practical challenges and help answer ongoing questions about complications and persistent symptoms. Robust surveillance will be essential to monitor the effectiveness and safety of future vaccines and other preventive measures.

Lyme Arthritis: A 50-Year Journey

Lyme arthritis (LA) was recognized as a separate entity in 1975 because of geographic clustering of children often diagnosed with juvenile rheumatoid arthritis in Lyme, Connecticut. After identification of erythema migrans as a common early feature of the illness, a prospective study of such patients implicated Ixodes scapularis ticks in disease transmission. In 1982, the causative agent, now called Borrelia burgdorferi, was cultured from these ticks and from Lyme disease patients. Subsequently, it was shown that LA could usually be treated successfully with oral antibiotics but sometimes required intravenous antibiotics. Yet, a small percentage of patients developed a dysregulated, proinflammatory immune response leading to persistent postinfectious synovitis with vascular damage, cytotoxic and autoimmune responses, and fibroblast proliferation, a lesion similar to that of rheumatoid arthritis. The message from postinfectious LA for other autoimmune arthritides is that a complex immune response with autoimmune features can begin with a microbial infection.

Vaccination to Prevent Lyme Disease: A Movement Towards Anti-Tick Approaches

Lyme disease is caused by the spirochete, Borrelia burgdorferi, which is transmitted by Ixodes spp ticks. The rise in Lyme disease cases since its discovery in the 1970s has reinforced the need for a vaccine. A vaccine based on B burgdorferi outer surface protein A (OspA) was approved by the Food and Drug Administration (FDA) several decades ago, but was pulled from the market a few years later, reportedly due to poor sales, despite multiple organizations concluding that it was safe and effective. Newer OspA-based vaccines are being developed and are likely to be available in the coming years. More recently, there has been a push to develop vaccines that target the tick vector instead of the pathogen to inhibit tick feeding and thus prevent transmission of tick-borne pathogens to humans and wildlife reservoirs. This review outlines the history of Lyme disease vaccines and this movement to anti-tick vaccine approaches.

Insights From Omics in Lyme Disease

Lyme disease is a zoonotic infection due to Ixodes tick-transmitted Borrelia burgdorferi sensu lato spirochetes and the most common vector-borne disease in the Northern Hemisphere. Despite nearly 50 years of investigation, the pathogenesis of this infection and its 2 main adverse outcomes-postinfectious Lyme arthritis and posttreatment Lyme disease syndrome-are incompletely understood. Advancement in sequencing and mass spectrometry have led to the rapid expansion of high-throughput omics technologies, including transcriptomics, metabolomics, and proteomics, which are now being applied to human diseases. This review summarizes findings of omics studies conducted on blood and tissue samples of people with acute Lyme disease and its postinfectious outcomes.

Tick-Borne Diseases

Ticks are responsible for the vast majority of vector-borne illnesses in the United States. The number of reported tick-borne disease (TBD) cases has more than doubled in the past 20 years. The majority of TBD cases occur in warm weather months in individuals with recent outdoor activities in wooded areas. The risk of contracting a TBD is also highly dependent on geographic location. Between 24 and 48 hours of tick attachment is required for most disease transmission to occur. Only 50% to 70% of patients with a TBD will recall being bitten by a tick, and TBDs are often initially misdiagnosed as a viral illness. Most TBDs are easily treated when diagnosed early in their course.

[Anthropization and tick-borne diseases: the example of Lyme borreliosis]

Ticks and tick-borne diseases are on the rise throughout the world. The reasons are multifactorial but all associated with human practices, including climate change and socio-economic and eco systemic changes. In the northern hemisphere, Lyme borreliosis and its vector, the tick belonging to the Ixodes ricinus complex, are particularly studied. Changes in forestry and the expansion of certain wild ungulates since the Second World War could explain the increasing presence of this tick in our environment. As it is likely to transmit other microorganisms potentially pathogenic to humans, an integrated multidisciplinary approach to identify human practices promoting its expansion is critical to control the (re)emergence of infectious diseases. Other ticks also benefit from the same anthropised context to increase their numbers in the environment.

By-degree Health and Economic Impacts of Lyme Disease, Eastern and Midwestern United States

Lyme disease (LD) is the most common vector-borne disease in the United States (U.S.). This paper assesses how climate change may influence LD incidence in the eastern and upper Midwestern U.S. and the associated economic burden. We estimated future Ixodes scapularis habitat suitability and LD incidence with a by-degree approach using variables from an ensemble of multiple climate models. We then applied estimates for present-day and projected habitat suitability for I. scapularis, present-day presence of Borrelia burgdorferi, and projected climatological variables to model reported LD incidence at the county level among adults, children, and the total population. Finally, we applied an estimate of healthcare expenses to project economic impacts. We show an overall increase in LD cases with regional variation. We estimate an increase in incidence in New England and the upper Midwestern U.S. and a concurrent decrease in incidence in Virginia and North Carolina. At 3°C of national warming from the 1986-2015 baseline climate, we project approximately 55,000 LD cases, a 38-percent increase from present-day estimates. At 6°C of warming, our most extreme scenario, we project approximately 92,000 LD cases in the region, an increase of 145 percent relative to current levels. Annual LD-related healthcare expenses at 3°C of warming are estimated to be $236 million (2021 dollars), approximately 38 percent greater than present-day. These results may inform decision-makers tasked with addressing climate risks, the public, and healthcare professionals preparing for treatment and prevention of LD.

Perinatal transmission of Lyme disease: A qualitative study investigating the research priorities of patients with Lyme disease in pregnancy

INTRODUCTION

Lyme disease is one of the most prevalent vector-borne disease in North America, yet its implications during pregnancy are poorly understood. Our knowledge of perinatal transmission of Lyme disease is limited due to the lack of robust epidemiological studies and longitudinal follow-up.

OBJECTIVES

This study aimed to understand the research priorities of people who have experienced Lyme disease in pregnancy and the feasibility of recruiting this population for future studies on perinatal transmission of Lyme disease. We also sought to understand the barriers and enablers to participating in research on perinatal transmission of Lyme disease.

METHODS

We conducted a qualitative study using focus groups and interviews with people who had experienced Lyme disease during pregnancy. English speaking participants were recruited through an online survey. There was no geographic restriction on participation. The focus groups and the interview were recorded and transcribed. Data were analyzed using interpretive content analysis.

RESULTS

Twenty people participated in four semi-structured focus groups and one semi-structured individual interview. The majority of participants were from North America. Participants' research priorities fell into five categories: transmission, testing, treatment, disease presentation, and education. All study participants expressed interest in future participation in research on Lyme disease in pregnancy and highlighted barriers and enablers to participation that could be addressed to facilitate future study recruitment.

CONCLUSION

The research priorities identified in this research would be well addressed through prospective research. People who experience Lyme disease in pregnancy are invested in continued research into perinatal transmission of Lyme disease.

Spondyloarthropathies and arthritis post-infection: a historical perspective

The spondyloarthropathies are a group of conditions characterised by spinal joint pain and have related clinical, epidemiological and genetic-related features. Ankylosing spondylitis, reactive arthritis, the spinal form of psoriatic arthritis and Crohn's and colitis enteropathic arthritis are the major clinical entities of the spondyloarthropathies, and principally occur in HLA-B27 positive individuals. Ankylosing spondylitis is much more common in males than females. Patients are usually seronegative for rheumatoid factor, and extra-articular features including iridocyclitis, mucous membrane and skin lesions: aortitis, may occur in some patients. The reactive arthritis form classically occurs following an infection of the gastrointestinal or genitourinary tract. The Crohn's and colitis enteropathic arthritis forms often have an associated large joint asymmetrical arthritis. Also discussed are acute rheumatic fever and Lyme disease which are conditions where the individual develops arthritis after an infection.

Microbes and Mental Illness: Past, Present, and Future

A review of the association between microbes and mental illness is performed, including the history, relevant definitions, infectious agents associated with mental illnesses, complex interactive infections, total load theory, pathophysiology, psychoimmunology, psychoneuroimmunology, clinical presentations, early-life infections, clinical assessment, and treatment. Perspectives on the etiology of mental illness have evolved from demonic possession toward multisystem biologically based models that include gene expression, environmental triggers, immune mediators, and infectious diseases. Microbes are associated with a number of mental disorders, including autism, schizophrenia, bipolar disorder, depressive disorders, and anxiety disorders, as well as suicidality and aggressive or violent behaviors. Specific microbes that have been associated or potentially associated with at least one of these conditions include Aspergillus, Babesia, Bartonella, Borna disease virus, Borrelia burgdorferi (Lyme disease), Candida, Chlamydia, coronaviruses (e.g., SARS-CoV-2), Cryptococcus neoformans, cytomegalovirus, enteroviruses, Epstein-Barr virus, hepatitis C, herpes simplex virus, human endogenous retroviruses, human immunodeficiency virus, human herpesvirus-6 (HHV-6), human T-cell lymphotropic virus type 1, influenza viruses, measles virus, Mycoplasma, Plasmodium, rubella virus, Group A Streptococcus (PANDAS), Taenia solium, Toxoplasma gondii, Treponema pallidum (syphilis), Trypanosoma, and West Nile virus. Recognition of the microbe and mental illness association with the development of greater interdisciplinary research, education, and treatment options may prevent and reduce mental illness morbidity, disability, and mortality.

A ticking time bomb hidden in plain sight

The deer tick transmits nearly half of the known tick-borne pathogens in the United States, and its expanding geographic range increases the risk of human infection. To decrease the abundance of and infection risk from deer ticks, approaches that include vaccines for human use and for animal hosts are desired.

From Tick to Test: A Comprehensive Review of Tick-Borne Disease Diagnostics and Surveillance Methods in the United States

Tick-borne diseases (TBDs) have become a significant public health concern in the United States over the past few decades. The increasing incidence and geographical spread of these diseases have prompted the implementation of robust surveillance systems to monitor their prevalence, distribution, and impact on human health. This comprehensive review describes key disease features with the geographical distribution of all known tick-borne pathogens in the United States, along with examining disease surveillance efforts, focusing on strategies, challenges, and advancements. Surveillance methods include passive and active surveillance, laboratory-based surveillance, sentinel surveillance, and a One Health approach. Key surveillance systems, such as the National Notifiable Diseases Surveillance System (NNDSS), TickNET, and the Tick-Borne Disease Laboratory Network (TBDLN), are discussed. Data collection and reporting challenges, such as underreporting and misdiagnosis, are highlighted. The review addresses challenges, including lack of standardization, surveillance in non-human hosts, and data integration. Innovations encompass molecular techniques, syndromic surveillance, and tick surveillance programs. Implications for public health cover prevention strategies, early detection, treatment, and public education. Future directions emphasize enhanced surveillance networks, integrated vector management, research priorities, and policy implications. This review enhances understanding of TBD surveillance, aiding in informed decision-making for effective disease prevention and control. By understanding the current surveillance landscape, public health officials, researchers, and policymakers can make informed decisions to mitigate the burden of (TBDs).

The Incidence of Lyme Borreliosis Among Children

BACKGROUND

First recognized in children in the United States, Lyme borreliosis (LB) is the most prevalent tickborne illness in North America and Europe. However, the incidence of LB in children, including geographic variation and difference from that in adults, is incompletely described.

METHODS

We compiled surveillance data from public health agency websites reporting age-stratified LB case data, which was combined with census data to derive incidence estimates. Additional incidence estimates were obtained through a systematic literature review.

RESULTS

We identified 18 surveillance systems and 15 published studies for derivation of LB incidence in children. National incidence of >10 cases in children per 100,000 per year were estimated for the United States and parts of Eastern, Western and Northern Europe. However, there was substantial variation in incidence among countries in some European regions. National incidence estimates from the literature largely aligned with estimates from surveillance. Surveillance-reported pediatric incidence was lower than adult incidence in adults in 8 countries, similar to adult incidence in 3 countries, and higher than adult incidence in 1 country. Among all pediatric age strata, the 5-9 years of age stratum had the highest proportion of pediatric cases in most countries.

CONCLUSIONS

As pediatric LB represents a substantial proportion of overall LB incidence across countries in Europe and North America, LB prevention and control efforts should target pediatric as well as adult populations. However, better data are needed to fully characterize the difference in incidence across geographic regions.

Development of an mRNA-lipid nanoparticle vaccine against Lyme disease

Lyme disease is the most common vector-borne infectious disease in the United States, in part because a vaccine against it is not currently available for humans. We propose utilizing the lipid nanoparticle-encapsulated nucleoside-modified mRNA (mRNA-LNP) platform to generate a Lyme disease vaccine like the successful clinical vaccines against SARS-CoV-2. Of the antigens expressed by Borrelia burgdorferi, the causative agent of Lyme disease, outer surface protein A (OspA) is the most promising candidate for vaccine development. We have designed and synthesized an OspA-encoding mRNA-LNP vaccine and compared its immunogenicity and protective efficacy to an alum-adjuvanted OspA protein subunit vaccine. OspA mRNA-LNP induced superior humoral and cell-mediated immune responses in mice after a single immunization. These potent immune responses resulted in protection against bacterial infection. Our study demonstrates that highly efficient mRNA vaccines can be developed against bacterial targets.

It's about time: small mammal communities and Lyme disease emergence

Theory predicts that biodiversity changes due to climate warming can mediate the rate of disease emergence. The mechanisms linking biodiversity-disease relationships have been described both theoretically and empirically but remain poorly understood. We investigated the relations between host diversity and abundance and Lyme disease risk in southern Quebec, a region where Lyme disease is rapidly emerging. We found that both the abundance of small mammal hosts and the relative abundance of the tick's natural host, the white-footed mouse (Peromyscus leucopus), influenced measures of disease risk in tick vectors (Borrelia burgdorferi infection abundance and prevalence in tick vectors). Our results suggest that the increase in Lyme disease risk is modulated by regional processes involving the abundance and composition of small mammal assemblages. However, the nature and strength of these relationships was dependent both on time and geographic area. The strong effect of P. leucopus abundance on disease risk we report here is of significant concern, as this competent host is predicted to increase in abundance and occurrence in the region, with the northern shift in the range of North American species under climate warming.

Touching Base with Some Mediterranean Diseases of Interest from Paradigmatic Cases at the "Magna Graecia" University Unit of Infectious Diseases: A Didascalic Review

Among infectious diseases, zoonoses are increasing in importance worldwide, especially in the Mediterranean region. We report herein some clinical cases from a third-level hospital in Calabria region (Southern Italy) and provide a narrative review of the most relevant features of these diseases from epidemiological and clinical perspectives. Further, the pathogenic mechanisms involved in zoonotic diseases are reviewed, focusing on the mechanisms used by pathogens to elude the immune system of the host. These topics are of particular concern for individuals with primary or acquired immunodeficiency (e.g., people living with HIV, transplant recipients, patients taking immunosuppressive drugs). From the present review, it appears that diagnostic innovations and the availability of more accurate methods, together with better monitoring of the incidence and prevalence of these infections, are urgently needed to improve interventions for better preparedness and response.

Lyme Disease Presenting With Interesting Neurological Features of Weakness and Hyporeflexia: A Case Report

Lyme disease is a tick-borne bacterial infection caused primarily by three pathogenic species of spirochete Borrelia (B. burgdorferi, B. afzelii, and B. garinii). It has a wide range of clinical manifestations ranging in severity. Although, it is generally divided into three phases: early localized, early disseminated, and late disease. Certain cases do not follow the same order described in standard books like Harrison's. Thus, it is vital to establish a chronological timeline when establishing the diagnosis. Here, we describe a 25-year-old female with numbness and tingling that began in her torso and then spread to her entire body. Physical examination revealed diminished motor reflexes and power, but the diagnosis of neuroborreliosis with monoradiculitis was only established with positive laboratory antibody evaluation and lumbar puncture. The patient's symptoms resolved quickly with a four-day inpatient course of IV ceftriaxone followed by 10 days of oral doxycycline.

Common Neurologic Features of Lyme Disease That May Present to a Rheumatologist

Lyme disease, caused by Borrelia burgdorferi (Bb) infection, has a broad spectrum of clinical manifestations and severity. Patients with possible Lyme disease may seek out or be referred to rheumatologists. Today, the most common reason to engage a rheumatologist is due to complaints of arthralgia. After skin, neurologic manifestations of Lyme disease are now among the most common. Therefore, it is important for rheumatologists to be aware of clues that suggest neurologic Lyme disease and prompt help from a neurologist experienced with Lyme disease.

Treatment of erythema migrans with doxycycline for 7 days versus 14 days in Slovenia: a randomised open-label non-inferiority trial

BACKGROUND

Lyme borreliosis is the most prevalent vector-borne disease in Europe and the USA. Doxycycline for 10 days is the primary treatment recommendation for erythema migrans. To reduce potentially harmful antibiotic overuse by identifying shorter effective treatments, we aimed to assess whether oral doxycycline for 7 days is non-inferior to 14 days in adults with solitary erythema migrans.

METHODS

In this randomised open-label non-inferiority trial, we enrolled patients with a solitary erythema at the University Medical Centre in Ljubljana, Slovenia. Patients were excluded if they were pregnant or lactating, immunosuppressed, allergic to doxycycline, or had received antibiotics with anti-borrelial activity within 10 days preceding enrolment or had additional manifestations of Lyme borreliosis Adults were randomly allocated 1:1 to receive oral doxycycline 100 mg twice a day for 7 days or 14 days. The primary efficacy endpoint was the difference in proportion of patients with treatment failure, defined as persistent erythema, new objective signs of Lyme borreliosis, or borrelial isolation on skin re-biopsy at 2 months, in a per-protocol analysis (the population that completed the assigned doxycycline regimen according to the study protocol and did not receive any other antibiotics with anti-borrelial activity until the 2-month visit). The non-inferiority margin was 6 percentage points. Safety was assessed in all randomly assigned patients who followed the study protocol and were evaluable at the 14-day visit. This study is registered with ClinicalTrials.gov, NCT03153267.

FINDINGS

Between July 3, 2017, and Oct 2, 2018, we enrolled 300 patients (150 per group: median age 56 years [IQR 47-65]; 126 [45%] of 300 male; skin culture positive 72 [30%] of 239 assessed). 295 patients completed antibiotic therapy as per protocol and 294 (98%) patients were evaluable 2 months post-enrolment. Five (3%) of 147 patients from the 7-day group versus 3 (2%) of 147 patients from the 14-day group (one patient did not attend the 2-month visit and was unreachable by telephone) had treatment failure manifesting as persistence of erythema (difference 1·4 percentage points; upper limit of one-sided 95% CI 5·2 percentage points; p=0·64). No patients developed new objective manifestations of Lyme borreliosis during follow-up or had positive repeat skin biopsies. Two (1%) of 150 patients in the 7-day and one (1%) of 150 patients in the 14-day group discontinued therapy due to adverse events.

INTERPRETATION

Our data support 7 days of oral doxycycline for adult European patients with solitary erythema migrans, permitting less antibiotic exposure than current guideline-driven therapy.

FUNDING

Slovenian Research Agency and the University Medical Centre Ljubljana.

Precipitation as a Possible Risk Factor for Development of Lyme Nephritis in Dogs

To determine whether increased precipitation in the months before diagnosis is predictive of Lyme nephritis in dogs, a symmetrical bidirectional case-crossover study was performed on 87 dogs with presumptive Lyme nephritis. Cases were geographically linked to the nearest precipitation monitoring station, and monthly total precipitation for the 4 mo preceding diagnosis was compared to monthly total precipitation 1 yr before and 1 yr after. Breeds affected included Labrador retrievers (n = 31), mixed-breed dogs (n = 19), and golden retrievers (n = 10), with a possible seasonal bimodal peak in spring and fall. In age-adjusted analysis, each additional inch of precipitation 3 mo before diagnosis was associated with an increase in the odds of developing Lyme nephritis (odds ratio 1.13, 95% confidence interval 1.01-1.25). The results suggest that increased precipitation is a possible risk factor for Lyme nephritis in dogs. These findings may provide useful information for the accurate diagnosis of dogs with protein-losing nephropathy and may guide future studies of risk factors for Lyme nephritis. The methodology employed here reinforces the concept that case-crossover designs have utility beyond acute exposures and outcomes and offer an attractive alternative for studies in companion animals.

An Overview of Anthropogenic Actions as Drivers for Emerging and Re-Emerging Zoonotic Diseases

Population growth and industrialization have led to a race for greater food and supply productivity. As a result, the occupation and population of forest areas, contact with wildlife and their respective parasites and vectors, the trafficking and consumption of wildlife, the pollution of water sources, and the accumulation of waste occur more frequently. Concurrently, the agricultural and livestock production for human consumption has accelerated, often in a disorderly way, leading to the deforestation of areas that are essential for the planet's climatic and ecological balance. The effects of human actions on other ecosystems such as the marine ecosystem cause equally serious damage, such as the pollution of this habitat, and the reduction of the supply of fish and other animals, causing the coastal population to move to the continent. The sum of these factors leads to an increase in the demands such as housing, basic sanitation, and medical assistance, making these populations underserved and vulnerable to the effects of global warming and to the emergence of emerging and re-emerging diseases. In this article, we discuss the anthropic actions such as climate changes, urbanization, deforestation, the trafficking and eating of wild animals, as well as unsustainable agricultural intensification which are drivers for emerging and re-emerging of zoonotic pathogens such as viral (Ebola virus, hantaviruses, Hendravirus, Nipah virus, rabies, and severe acute respiratory syndrome coronavirus disease-2), bacterial (leptospirosis, Lyme borreliosis, and tuberculosis), parasitic (leishmaniasis) and fungal pathogens, which pose a substantial threat to the global community. Finally, we shed light on the urgent demand for the implementation of the One Health concept as a collaborative global approach to raise awareness and educate people about the science behind and the battle against zoonotic pathogens to mitigate the threat for both humans and animals.

Autoimmunity: Are we asking the right question?

For decades, the main question immunologists have asked about autoimmunity is "what causes a break in self-tolerance?" We have not found good answers to that question, and I believe we are still so ignorant because it's the wrong question. Rather than a break in self-tolerance, I suggest that many autoimmune diseases might be due to defects in normal tissue physiology.

Testing Raman spectroscopy as a diagnostic approach for Lyme disease patients

Lyme disease (LD), the leading tick-borne disease in the Northern hemisphere, is caused by spirochetes of several genospecies of the Borreliella burgdorferi sensu lato complex. LD is a multi-systemic and highly debilitating illness that is notoriously challenging to diagnose. The main drawbacks of the two-tiered serology, the only approved diagnostic test in the United States, include poor sensitivity, background seropositivity, and cross-reactivity. Recently, Raman spectroscopy (RS) was examined for its LD diagnostic utility by our earlier proof-of-concept study. The previous investigation analyzed the blood from mice that were infected with 297 and B31 strains of Borreliella burgdorferi sensu stricto (s.s.). The selected strains represented two out of the three major clades of B. burgdorferi s.s. isolates found in the United States. The obtained results were encouraging and prompted us to further investigate the RS diagnostic capacity for LD in this study. The present investigation has analyzed blood of mice infected with European genospecies, Borreliella afzelii or Borreliella garinii, or B. burgdorferi N40, a strain of the third major class of B. burgdorferi s.s. in the United States. Moreover, 90 human serum samples that originated from LD-confirmed, LD-negative, and LD-probable human patients were also analyzed by RS. The overall results demonstrated that blood samples from Borreliella-infected mice were identified with 96% accuracy, 94% sensitivity, and 100% specificity. Furthermore, human blood samples were analyzed with 88% accuracy, 85% sensitivity, and 90% specificity. Together, the current data indicate that RS should be further explored as a potential diagnostic test for LD patients.

Tierärztliches Meinungsbild zur Equinen Lyme-Borreliose – Ergebnisse einer Fragebogenstudie

Ziel Erfassung des tierärztlichen Meinungsbildes zur Equinen Lyme-Borreliose

Material und Methoden Durch eine Befragung wurde untersucht, wie Pferdetierärzte die Bedeutung positiver serologischer Nachweise gegen Borrelia burgdorferi (Bb-AK) und einer klinisch manifesten Lyme-Borreliose (LB) einschätzten sowie letztere diagnostizieren und therapieren.

Ergebnisse Der Fragebogen wurde von 73 Tierärzten (TÄ) ausgefüllt. 48 % der TÄ erhoben nur sehr selten bis gar keine serologischen Bb-AK-Nachweise bei Pferden in ihrer Praxis, 47 % stellten gelegentlich Bb-AK fest und nur 5 % fanden häufig Bb-AK-Nachweise. 51 % der TÄ bestätigen, dass sie bereits klinisch-manifeste LB-Erkrankungen festgestellt hätten, während 43 % die Existenz dieser Erkrankung zwar nicht ausschlossen, aber selber keine Equine Lyme-Borreliose Fälle gesehen haben. 6 % der TÄ zweifeln die Existenz einer klinischen LB beim Pferd generell an.

Im Durchschnitt wurden 159-mal im Jahr weiterführende diagnostische Maßnahmen im Hinblick auf eine LB eingeleitet, und es wurden 1,4 ± 1,0 Fälle von equiner LB im Jahr diagnostiziert. Als Untersuchungsmethoden zur Abklärung von Borreliose-Verdachtsfällen verwendeten 68 % der TÄ den „indirekten Erregernachweis“, 27 % sowohl den direkten als auch den indirekten Erregernachweis und 5 % verwendeten ausschließlich den direkten Erregernachweis. Bei letzterem wurden am häufigsten Blut und Hautstanzen als Probenmaterial eingesandt.

Die Behandlung von Pferden mit auf eine Borrelioseerkrankung hinweisenden Laborergebnissen und als passend bewerteter, klinischer Symptomatik erfolgte durch 93 % der Tierärzte mit Antibiotika und 7 % mit Homöopathie. Am häufigsten wurde Doxycyclin (68 %) eingesetzt. Dabei erfolgte die antibiotische Behandlung über einen Zeitraum von 3 (31 %) bis 4 (63 %) Wochen.

In Bezug auf eine mögliche Impfung der Pferde gegen Borreliose boten 39 % der Tierärzte diese Impfung nicht an, bei 20 % wurde sie noch nicht eingesetzt, aber auch nicht kategorisch abgelehnt und 41 % führten regelmäßig Borreliose-Impfungen durch.

Schlussfolgerung und klinische Relevanz Das Meinungsbild von praktizierenden Pferdetierärztinnen und Pferdetierärzten in Deutschland zur klinischen Relevanz der equinen LB ist sehr heterogen. Einheitliche Richtlinien hinsichtlich Diagnostik- und evtl. auch Therapieempfehlungen wären sinnvoll, um der Unsicherheit in der Tierärzteschaft entgegenzuwirken.

Large-Scale Sequencing of Borreliaceae for the Construction of Pan-Genomic-Based Diagnostics

The acceleration of climate change has been associated with an alarming increase in the prevalence and geographic range of tick-borne diseases (TBD), many of which have severe and long-lasting effects-particularly when treatment is delayed principally due to inadequate diagnostics and lack of physician suspicion. Moreover, there is a paucity of treatment options for many TBDs that are complicated by diagnostic limitations for correctly identifying the offending pathogens. This review will focus on the biology, disease pathology, and detection methodologies used for the Borreliaceae family which includes the Lyme disease agent Borreliella burgdorferi. Previous work revealed that Borreliaceae genomes differ from most bacteria in that they are composed of large numbers of replicons, both linear and circular, with the main chromosome being the linear with telomeric-like termini. While these findings are novel, additional gene-specific analyses of each class of these multiple replicons are needed to better understand their respective roles in metabolism and pathogenesis of these enigmatic spirochetes. Historically, such studies were challenging due to a dearth of both analytic tools and a sufficient number of high-fidelity genomes among the various taxa within this family as a whole to provide for discriminative and functional genomic studies. Recent advances in long-read whole-genome sequencing, comparative genomics, and machine-learning have provided the tools to better understand the fundamental biology and phylogeny of these genomically-complex pathogens while also providing the data for the development of improved diagnostics and therapeutics.

Lyme Disease in Children

Lyme disease is now the most frequently reported vector-borne disease in the United States. The highest incidence is in children aged 5 to 9 years with a male predominance. The most common manifestation, erythema migrans, is sometimes not recognized, leading to risk of complications. Testing for Lyme disease should only be done if there is a consistent clinical syndrome with exposure in a Lyme-endemic area. Most forms of Lyme disease are successfully treated with short courses of oral therapy. Prevention and management of tick bites is important.

Lyme Arthritis

Arthritis is the most common late manifestation of Borrelia burgdorferi infection in the United States, usually beginning months after the tick bite. In most patients with Lyme arthritis (LA) today, arthritis is the presenting manifestation of the disease. Patients have swelling and pain in one or a few large joints, especially the knee. Serologic testing is the mainstay of diagnosis. Responses to antibiotic treatment are generally excellent, although a small percentage of patients have persistent, postinfectious synovitis after 2 to 3 months of oral and IV antibiotics, which respond to anti-inflammatory therapies. Herein we review the clinical presentation, diagnosis, and management of LA.

Infection with Borrelia burgdorferi Increases the Replication and Dissemination of Coinfecting Powassan Virus in Ixodes scapularis Ticks

Powassan virus (POWV) is a tick-borne neuroinvasive flavivirus endemic to North America. It is generally transmitted by the tick, Ixodes scapularis. This species also transmits Borrelia burgdorferi, the causative agent of Lyme disease. Infection with B. burgdorferi can result in arthritis, carditis, and neuroborreliosis. These pathogens experience sylvatic overlap. To determine the risk of human exposure to coinfected ticks, the interactions between POWV and B. burgdorferi are assessed in laboratory-infected I. scapularis. Adult male and female I. scapularis ticks are orally inoculated with either both pathogens, POWV only, B. burgdorferi only, or uninfected media. After twenty-one days, the ticks are dissected, and RNA is extracted from their midguts and salivary glands. In infected midguts, the quantity of POWV in coinfected ticks was elevated compared to those with only POWV. In addition, the salivary glands of ticks with infected midguts had increased POWV dissemination to those with only POWV. RNA sequencing is performed to identify the potential mechanism for this pattern, which varies between the organs. Ixodes scapularis ticks are found to be capable of harboring both POWV and B. burgdorferi with a benefit to POWV replication and dissemination.

Effectiveness of personal protection measures against Lyme disease: A review of epidemiologic studies from the United States

Lyme disease, the most commonly reported vector-borne disease in the United States, is caused by the bacteria Borrelia burgdorferi and is transmitted through the bite of an infected blacklegged tick. In the absence of a licensed vaccine, the prevention of Lyme disease relies heavily on limiting tick exposure. Methods for limiting tick exposure include personal protection measures such as repellent use, wearing protective clothing, avoiding areas where ticks may be present, bathing after exposure to tick habitat and performing regular tick checks. Public health officials typically recommend all these personal protection measures; however, there is limited evidence to promote one behaviour or practice over another. The focus of this article is to review available literature that examines the effectiveness of recommended personal protection measures to prevent Lyme and other Ixodes-transmitted diseases in humans. Articles included in this review were identified through Google Scholar and PubMed searches using specific search terms. We identified over 56,000 articles using Google Scholar and PubMed searches. Of those, 16 studies fit our criteria for inclusion and were reviewed in their entirety. Among the personal protection measures evaluated, no intervention was predominantly or consistently effective across studies, demonstrating that, currently, there is no single best method for primary prevention of Ixodes-transmitted diseases in the United States. Frequently recommended practices such as tick checks, repellent use and protective clothing had mixed results across studies. Study design differences limited comparability among studies, and sample sizes for these studies may have been too small to detect statistically significant results even if a prevention method was effective. Though many of the reviewed personal protection measures are frequently recommended to the public, limited evidence demonstrates their ability to prevent tick-borne disease. Additional standardized studies are needed to evaluate personal protection measures.

Characteristics of Lyme optic neuritis: a case report of Lyme associated bilateral optic neuritis and systematic review of the literature

Optic Neuritis is rare in Lyme borreliosis. The current knowledge of optic nerve involvement in Lyme borreliosis relies solely on case reports. The aim of this systematic review was to characterize and investigate the associated factors of optic neuritis in Lyme borreliosis. We further presented a very rare case of isolated bilateral optic neuritis in a Lyme seropositive patient.

Disease-Associated Multimolecular Signature in the Urine of Patients with Lyme Disease Detected Using Raman Spectroscopy and Chemometrics

A urine-based screening technique for Lyme disease (LD) was developed in this research. The screen is based on Raman spectroscopy, iterative smoothing-splines with root error adjustment (ISREA) spectral baselining, and chemometric analysis using Rametrix software. Raman spectra of urine from 30 patients with positive serologic tests (including the US Centers for Disease Control [CDC] two-tier standard) for LD were compared against subsets of our database of urine spectra from 235 healthy human volunteers, 362 end-stage kidney disease (ESKD) patients, and 17 patients with active or remissive bladder cancer (BCA). We found statistical differences (p < 0.001) between urine scans of healthy volunteers and LD-positive patients. We also found a unique LD molecular signature in urine involving 112 Raman shifts (31 major Raman shifts) with significant differences from urine of healthy individuals. We were able to distinguish the LD molecular signature as statistically different (p < 0.001) from the molecular signatures of ESKD and BCA. When comparing LD-positive patients against healthy volunteers, the Rametrix-based urine screen performed with 86.7% for overall accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), respectively. When considering patients with ESKD and BCA in the LD-negative group, these values were 88.7% (accuracy), 83.3% (sensitivity), 91.0% (specificity), 80.7% (PPV), and 92.4% (NPV). Additional advantages to the Raman-based urine screen include that it is rapid (minutes per analysis), is minimally invasive, requires no chemical labeling, uses a low-profile, off-the-shelf spectrometer, and is inexpensive relative to other available LD tests.

The evolving story of Borrelia burgdorferi sensu lato transmission in Europe

Beside mosquitoes, ticks are well-known vectors of different human pathogens. In the Northern Hemisphere, Lyme borreliosis (Eurasia, LB) or Lyme disease (North America, LD) is the most commonly occurring vector-borne infectious disease caused by bacteria of the genus Borrelia which are transmitted by hard ticks of the genus Ixodes. The reported incidence of LB in Europe is about 22.6 cases per 100,000 inhabitants annually with a broad range depending on the geographical area analyzed. However, the epidemiological data are largely incomplete, because LB is not notifiable in all European countries. Furthermore, not only differ reporting procedures between countries, there is also variation in case definitions and diagnostic procedures. Lyme borreliosis is caused by several species of the Borrelia (B.) burgdorferi sensu lato (s.l.) complex which are maintained in complex networks including ixodid ticks and different reservoir hosts. Vector and host influence each other and are affected by multiple factors including climate that have a major impact on their habitats and ecology. To classify factors that influence the risk of transmission of B. burgdorferi s.l. to their different vertebrate hosts as well as to humans, we briefly summarize the current knowledge about the pathogens including their astonishing ability to overcome various host immune responses, regarding the main vector in Europe Ixodes ricinus, and the disease caused by borreliae. The research shows, that a higher standardization of case definition, diagnostic procedures, and standardized, long-term surveillance systems across Europe is necessary to improve clinical and epidemiological data.

The year that shaped the outcome of the OspA vaccine for human Lyme disease

The expansion of Lyme borreliosis endemic areas and the corresponding increase of disease incidence have opened the possibility for greater acceptance of a vaccine. In this perspective article, we discuss the discovery of outer surface protein A (OspA) of B. burgdorferi, and the subsequent pre-clinical testing and clinical trials of a recombinant OspA vaccine for human Lyme disease. We also discuss in detail the open public hearings of the FDA Lyme disease vaccine advisory panel held in 1998 where concerns of molecular mimicry induced autoimmunity to native OspA were raised, the limitations of those studies, and the current modifications of recombinant OspA to develop a multivalent subunit vaccine for Lyme disease.

Stages of Lyme Arthritis

BACKGROUND/HISTORICAL PERSPECTIVE

Lyme arthritis was described in 1977, after an apparent outbreak of juvenile idiopathic arthritis in Lyme, Connecticut. The evolution of the disease has been meticulously described with presentation dependent on disease duration and previous therapy.

SUMMARY INTEGRATING PUBLISHED LITERATURE

Erythema migrans is typically the first manifestation. Untreated patients often develop early disseminated disease, characterized by migratory polyarthralgia, potentially with cardiac and/or neurologic sequelae. If untreated, most patients develop late Lyme arthritis, characterized as a monoarthritis or oligoarthritis, typically involving the knees. Serologies are strongly positive at this stage; if positive, Lyme PCR from synovial fluid confirms the diagnosis. Doxycycline is recommended for late Lyme arthritis, although amoxicillin or ceftriaxone may be considered.Initial antibiotic therapy for late Lyme arthritis is insufficient for a subset of patients. However, serologies and synovial fluid PCR are not useful at determining whether infection persists after oral therapy. As such, ceftriaxone is recommended in patients with inadequate response to doxycycline or amoxicillin.Approximately 10% of patients have persistent arthritis despite antimicrobial therapy, termed postinfectious Lyme arthritis, which is thought to be related to prolonged inflammation and unique microbial and host interaction. Therapy at this stage relies on immunosuppression and/or synovectomy.

MAJOR CONCLUSIONS AND FUTURE RESEARCH

Lyme arthritis provides unique insights into the complex interplay between microbes and host immunity. The progression from localized erythema migrans to early disseminated disease and late Lyme arthritis allows insight into arthritis initiation, and the study of postinfectious Lyme arthritis allows further insight into mechanisms of arthritis persistence.

Prevalence of Risk and Protective Factors for Tick Exposure and Tick-Borne Disease Among Residents of Indiana

OBJECTIVE

To determine the prevalence of risk and protective factors for tick exposure and tick-borne disease (TBD) based on gender and living in urban or rural areas (urbanicity) among a cross section of Indiana adults.

METHODS

Data were collected from 3003 adults (81% response rate) spread across all 92 Indiana counties. Study participants were recruited from existing online panels maintained by Qualtrics. We calculated prevalence ratio (PR) and 95% confidence interval (CI) of 8 primary outcomes for 2 different exposures: (1) gender (male/female) and (2) urbanicity.

RESULTS

Female participants were 10% less likely to find a tick on themselves than male participants (PR = 0.90; 95% CI, 0.74-0.99) and significantly more likely to worry about their health and safety because of ticks, whereas males avoided the outdoors less because of worry about ticks. Female participants were significantly more likely to adopt various personal protective measures, specifically because of concern for ticks. Female participants were also less likely to have been told by a health care provider that they have a TBD (PR = 0.53; 95% CI, 0.38-0.75). Rural participants were significantly more likely to report seeing a tick at their residential property (PR = 2.40; 95% CI, 2.11-2.76), report finding ticks on themselves (PR = 1.90; 95% CI, 1.68-2.23), and report finding a tick on a child at their residential property within the past 6 months than urban dwellers (PR = 1.37; 95% CI, 1.06-1.77). In addition, we found that 62% of participants have very high trust in government sources of information on TBD and tick prevention.

CONCLUSIONS

In Indiana, the area around people's residences may constitute an important source of tick exposure for humans. Being exposed to ticks is most prevalent in those living in rural areas of Indiana. Finally, risk factors for TBD are higher among males than among females.

Existing Data Sources for Clinical Epidemiology: The Danish Study Group of Infections of the Brain Database (DASGIB)

Central nervous system (CNS) infections are rare diseases that are associated with considerable morbidity and mortality. Increased knowledge based on contemporary data is a prerequisite for improved management and prevention of these serious conditions. Yet, population-based databases of patients hospitalized with CNS infections remain scarce. The Danish Study Group of Infections of the Brain (DASGIB) has prospectively registered information on all adults ≥18 years of age admitted with CNS infections at departments of infectious diseases in Denmark since 2015. The main variables collected are baseline demographics, blood and cerebrospinal fluid tests, imaging results, and outcome using the Glasgow Outcome Scale score. To investigate important aspects for each type of CNS infections, additional variables are included specifically for bacterial meningitis, viral meningitis, encephalitis, brain abscess, neurosyphilis, and Lyme neuroborreliosis. From 2015 to 2020, a total of 3579 cases of CNS infections have been recorded in the DASGIB database. Using the unique civil registration number assigned to all Danish residents, the database can be unambiguously linked with nationwide healthcare registries at the individual level. This enables researchers to conduct detailed population-based and longitudinal observational studies of risk and prognosis of CNS infections and to compare them with matched population cohorts. The database is well-suited for epidemiological research and the DASGIB network forms a solid infrastructure for future national and international collaborations.

Lyme arthritis in Western Europe: a multicentre retrospective study

To characterize Lyme arthritis, with a focus on management, and outcome. Observational retrospective multicentre study in Western France, of all consecutive cases of Lyme arthritis, documented by Borrelia burgdorferi IgG on ELISA serological testing, confirmed by Western blot, with or without positive Borrelia PCR in synovial fluid, with no alternative diagnosis. We enrolled 52 patients (29 males), with a mean age of 43 ± 19.4 years. Most patients had monoarthritis (n = 43, 82.7%), involving the knee (n = 51, 98.1%), with a median delay between symptoms onset and Lyme arthritis diagnosis of 5 months (interquartile range, 1.5-8). Synovial fluid analysis yielded median white cell count of 16,000/mm³ (9230-40,500), and positive PCR in 16 cases (39%), for B. burgdorferi sensu stricto (n = 5), B. garinii (n = 5), B. afzelii (n = 3), and undetermined (n = 3). All patients received antibiotics, for a median duration of 28 days (21-30), with doxycycline (n = 44, 84.6%), ceftriaxone (n = 6, 11.5%), or amoxicillin (n = 2). Twelve patients (23.1%) also received intra-articular injection of glucocorticoids as first-line treatment. Of 47 patients with follow-up, 35 (74.5%) had complete resolution of Lyme arthritis. Lyme arthritis in Western Europe may be due to B. burgdorferi ss, B. afzelii, or B. garinii. Clinical presentation is similar to Lyme arthritis in North America (i.e. chronic knee monoarthritis), with low sensitivity of synovial fluid PCR (39%).

Comparison of Lyme Disease in the United States and Europe

Lyme disease, or Lyme borreliosis, is the most common tickborne disease in the United States and Europe. In both locations, Ixodes species ticks transmit the Borrelia burgdorferi sensu lato bacteria species responsible for causing the infection. The diversity of Borrelia species that cause human infection is greater in Europe; the 2 B. burgdorferi s.l. species collectively responsible for most infections in Europe, B. afzelii and B. garinii, are not found in the United States, where most infections are caused by B. burgdorferi sensu stricto. Strain differences seem to explain some of the variation in the clinical manifestations of Lyme disease, which are both minor and substantive, between the United States and Europe. Future studies should attempt to delineate the specific virulence factors of the different species of B. burgdorferi s.l. responsible for these variations in clinical features.

Molecular Mechanisms of Borrelia burgdorferi Phagocytosis and Intracellular Processing by Human Macrophages

Lyme disease is the most common vector-borne illness in North America and Europe. Its causative agents are spirochetes of the Borrelia burgdorferi sensu latu complex. Infection with borreliae can manifest in different tissues, most commonly in the skin and joints, but in severe cases also in the nervous systems and the heart. The immune response of the host is a crucial factor for preventing the development or progression of Lyme disease. Macrophages are part of the innate immune system and thus one of the first cells to encounter infecting borreliae. As professional phagocytes, they are capable of recognition, uptake, intracellular processing and final elimination of borreliae. This sequence of events involves the initial capture and internalization by actin-rich cellular protrusions, filopodia and coiling pseudopods. Uptake into phagosomes is followed by compaction of the elongated spirochetes and degradation in mature phagolysosomes. In this review, we discuss the current knowledge about the processes and molecular mechanisms involved in recognition, capturing, uptake and intracellular processing of Borrelia by human macrophages. Moreover, we highlight interactions between macrophages and other cells of the immune system during these processes and point out open questions in the intracellular processing of borreliae, which include potential escape strategies of Borrelia.

Posttreatment Lyme Disease Syndrome-What It Might Be and What It Is Not

Lyme disease is a multisystem disease caused by Borrelia burgdorferi infection and accounts for well-defined manifestations, appearing either at an early or late stage. Appropriate antibiotic therapy generally leads to a favorable outcome. Still, unspecific persisting symptoms such as fatigue, myalgia, arthralgia or cognitive dysfunction are reported by several patients months to years after adequate treatment. Their underlying pathophysiologic mechanism is unclear. However, there is no evidence for microbiological persistence in these cases and attempts to resolve the symptoms by repeated or prolonged antibiotic treatment have not been convincingly successful, but they may rather be harmful. To narrow down the controversially handled entity of posttreatment Lyme disease syndrome (PTLDS) and to avoid overdiagnosis and overtreatment, case definitions have been proposed, acknowledging PTLDS as a complex of nonspecific, subjective symptoms, which are neither caused by ongoing infection nor by any other identifiable disease. PTLDS is mainly a diagnosis of exclusion and requires careful evaluation of differential diagnosis followed by counseling about optimal management in light of missing specific therapeutic options.

Common low complexity regions for SARS-CoV-2 and human proteomes as potential multidirectional risk factor in vaccine development

BACKGROUND

The rapid spread of the COVID-19 demands immediate response from the scientific communities. Appropriate countermeasures mean thoughtful and educated choice of viral targets (epitopes). There are several articles that discuss such choices in the SARS-CoV-2 proteome, other focus on phylogenetic traits and history of the Coronaviridae genome/proteome. However none consider viral protein low complexity regions (LCRs). Recently we created the first methods that are able to compare such fragments.

RESULTS

We show that five low complexity regions (LCRs) in three proteins (nsp3, S and N) encoded by the SARS-CoV-2 genome are highly similar to regions from human proteome. As many as 21 predicted T-cell epitopes and 27 predicted B-cell epitopes overlap with the five SARS-CoV-2 LCRs similar to human proteins. Interestingly, replication proteins encoded in the central part of viral RNA are devoid of LCRs.

CONCLUSIONS

Similarity of SARS-CoV-2 LCRs to human proteins may have implications on the ability of the virus to counteract immune defenses. The vaccine targeted LCRs may potentially be ineffective or alternatively lead to autoimmune diseases development. These findings are crucial to the process of selection of new epitopes for drugs or vaccines which should omit such regions.

Lyme disease: "End of the debate?"

Lyme borreliosis is a tick-borne disease that is widespread throughout the northern hemisphere. Ixodes ricinus is present throughout metropolitan France, except for the Mediterranean region. The debate revolves around whether or not a chronic form of Lyme disease exists. This controversy is not limited to France but has been reported worldwide. In France, in 2019, 24 scientific societies representing the medical disciplines most involved in Lyme disease, including the Société Française de Rhumatologie (French Rheumatology Society [SFR]) and the Société de Pathologie Infectieuse de la Langue Française (French Infectious Disease Society-SPILF), published recommendations on the management of Lyme borreliosis following a submission to the Director General of Health. These recommendations conflict with those of the Haute Autorité de Santé (HAS), a multi-specialties independent group of physician, on a key point: whether to add a new nosological entity labeled as "persistent polymorphous signs and symptoms (or syndrome) possibly due to tick bite." The creation of this new syndrome risks should increase anchoring bias, leading to the attribution of all symptoms to a possible tick bite, without considering differential diagnoses. Lyme disease has been extensively studied. Erythema migrans is the primary clinical manifestation. In the presence of nonmetabolic, nonseptic monoarthritis involving the knee or radiculitis of a lower limb during the summer, Lyme disease should be suspected. Serologic testing for Lyme disease is reliable in the case of late forms such as chronic arthritis, while the detection of Borrelia DNA in synovial fluid by PCR is inconsistent. Sometimes, the serology can be misleading in early forms such as radiculitis. Treatment is based on doxycycline for 14 days in early forms (radiculitis), or 28 days in late forms (arthritis). Arthritis can persist or recur after antibiotic therapy. The prevalence of a diffuse polyalgia syndrome (fibromyalgia) following Lyme disease does not seem to differ much from that in the general population. It is not improved by prolonged antibiotic therapy, which is therefore not recommended.