Incidence of Clinician-Diagnosed Lyme Disease, United States, 2005-2010

Role of NK-Like CD8+ T Cells during Asymptomatic Borrelia burgdorferi Infection

Lyme disease (LD) due to Borrelia burgdorferi is the most prevalent vector-borne disease in the United States. There is a poor understanding of how immunity contributes to bacterial control, pathology, or both during LD. Dogs in an area of endemicity were screened for B. burgdorferi and Anaplasma exposure and stratified according to seropositivity, presence of LD symptoms, and doxycycline treatment. Significantly elevated serum interleukin-21 (IL-21) and increased circulating CD3⁺ CD94⁺ lymphocytes with an NK-like CD8⁺ T cell phenotype were predominant in asymptomatic dogs exposed to B. burgdorferi. Both CD94⁺ T cells and CD3^- CD94⁺ lymphocytes, corresponding to NK cells, from symptomatic dogs expressed gamma interferon (IFN-γ) at a 3-fold-higher frequency upon stimulation with B. burgdorferi than the same subset among endemic controls. Surface expression of activating receptor NKp46 was reduced on CD94⁺ T cells from LD, compared to cells after doxycycline treatment. A higher frequency of NKp46-expressing CD94⁺ T cells correlated with significantly increased peripheral blood mononuclear cell (PBMC) cytotoxic activity via calcein release assay. PBMCs from dogs with symptomatic LD showed significantly reduced killing ability compared with endemic control PBMCs. An elevated NK-like CD8⁺ T cell response was associated with protection against development of clinical LD, while excess IFN-γ was associated with clinical disease.

Vaccines for Lyme Borreliosis: Facts and Challenges

Lyme borreliosis (LB) is a multisystem infectious disease abundant in the northern countries of the world and is caused by Borrelia species. Vaccination against LB is an effective way to prevent and reduce the number of diseases in endemic areas. Several vaccines have been developed and tested in the past, but no human LB vaccine is currently available on the market. This review aims to uncover and delineate various strategies and diverse technological approaches related to vaccine production. Furthermore, we characterize already tested vaccines, possibilities for their future development, and reasons for their failure.

Emergence of Lyme Disease on the French Riviera, a Retrospective Survey

Background

The French Riviera has been declared free of Lyme Borreliosis (LB) for years. Many patients are referred for presumed LB, sometimes with atypical clinical signs and/or doubtful serology, calling the diagnosis into question.

Methods

Patients were assessed for LB diagnosis, depending on clinical presentation, laboratory findings, and further examination by other medical professionals.

Results

Among 255 patients, 45 (18%) were classified as confirmed LB cases [including 28 ongoing LB (10%) and 17 past LB (8%)], and for 210 (82%) a Lyme borreliosis diagnosis was ruled out. Among ongoing LB, 56% had been exposed to or bitten by ticks, exclusively in rural locations of the Alpes-Maritimes. As a result of the diagnostic procedure, 132 (52%) patients had been treated. An alternative diagnosis was established for 134 (52%) patients, covering a wide range of conditions, including mainly psychological (28%) and neurological conditions (25%) or inflammatory and systemic diseases (22%).

Conclusions

Our results strongly suggest the endemicity of LB in the Alpes-Maritimes region. Confirmed LB accounted for 18% of patients while 52% were diagnosed with other conditions.

Risk factors for Lyme disease stage and manifestation using electronic health records

BACKGROUND

Little is known about risk factors for early (e.g., erythema migrans) and disseminated Lyme disease manifestations, such as arthritis, neurological complications, and carditis. No study has used both diagnoses and free text to classify Lyme disease by disease stage and manifestation.

METHODS

We identified Lyme disease cases in 2012-2016 in the electronic health record (EHR) of a large, integrated health system in Pennsylvania. We developed a rule-based text-matching algorithm using regular expressions to extract clinical data from free text. Lyme disease cases were then classified by stage and manifestation using data from both diagnoses and free text. Among cases classified by stage, we evaluated individual, community, and health care variables as predictors of disseminated stage (vs. early) disease using Poisson regression models with robust errors. Final models adjusted for sociodemographic factors, receipt of Medical Assistance (i.e., Medicaid, a proxy for low socioeconomic status), primary care contact, setting of diagnosis, season of diagnosis, and urban/rural status.

RESULTS

Among 7310 cases of Lyme disease, we classified 62% by stage. Overall, 23% were classified using both diagnoses and text, 26% were classified using diagnoses only, and 13% were classified using text only. Among the staged diagnoses (n = 4530), 30% were disseminated stage (762 arthritis, 426 neurological manifestations, 76 carditis, 95 secondary erythema migrans, and 76 other manifestations). In adjusted models, we found that persons on Medical Assistance at least 50% of time under observation, compared to never users, had a higher risk (risk ratio [95% confidence interval]) of disseminated Lyme disease (1.20 [1.05, 1.37]). Primary care contact (0.59 [0.54, 0.64]) and diagnosis in the urgent care (0.22 [0.17, 0.29]), compared to the outpatient setting, were associated with lower risk of disseminated Lyme disease.

CONCLUSIONS

The associations between insurance payor, primary care status, and diagnostic setting with disseminated Lyme disease suggest that lower socioeconomic status and less health care access could be linked with disseminated stage Lyme disease. Intervening on these factors could reduce the individual and health care burden of disseminated Lyme disease. Our findings demonstrate the value of both diagnostic and narrative text data to identify Lyme disease manifestations in the EHR.

Evaluating public acceptability of a potential Lyme disease vaccine using a population-based, cross-sectional survey in high incidence areas of the United States

BACKGROUND

Lyme disease incidence is increasing, despite current prevention options. New Lyme disease vaccine candidates are in development, however, investigation of the acceptability of a Lyme disease vaccine among potential consumers is needed prior to any vaccine coming to market. We conducted a population-based, cross-sectional study to estimate willingness to receive a potential Lyme disease vaccine and factors associated with willingness.

METHODS

The web-based survey was administered to a random sample of Connecticut, Maryland, Minnesota, and New York residents June-July 2018. Survey-weighted descriptive statistics were conducted to estimate the proportion willing to receive a potential Lyme disease vaccine. Multivariable multinomial logistic regression models were used to quantify the association of sociodemographic characteristics and Lyme disease vaccine attitudes with willingness to be vaccinated.

RESULTS

Surveys were completed by 3313 respondents (6% response rate). We estimated that 64% of residents were willing to receive a Lyme disease vaccine, while 30% were uncertain and 7% were unwilling. Compared to those who were willing, those who were uncertain were more likely to be parents, adults 45-65 years old, non-White, have less than a bachelor's degree, or have safety concerns about a potential Lyme disease vaccine. Those who were unwilling were also more likely to be non-White, have less than a bachelor's degree, or have safety concerns about a potential Lyme disease vaccine. In addition, the unwilling had low confidence in vaccines in general, had low perceived risk of contracting Lyme disease, and said they would not be influenced by a positive recommendation from a healthcare provider.

DISCUSSION

Overall, willingness to receive a Lyme disease vaccine was high. Effective communication by clinicians regarding safety and other vaccine parameters to those groups who are uncertain will be critical for increasing vaccine uptake and reducing Lyme disease incidence.

Identification of public submitted tick images: A neural network approach

Ticks and tick-borne diseases represent a growing public health threat in North America and Europe. The number of ticks, their geographical distribution, and the incidence of tick-borne diseases, like Lyme disease, are all on the rise. Accurate, real-time tick-image identification through a smartphone app or similar platform could help mitigate this threat by informing users of the risks associated with encountered ticks and by providing researchers and public health agencies with additional data on tick activity and geographic range. Here we outline the requirements for such a system, present a model that meets those requirements, and discuss remaining challenges and frontiers in automated tick identification. We compiled a user-generated dataset of more than 12,000 images of the three most common tick species found on humans in the U.S.: Amblyomma americanum, Dermacentor variabilis, and Ixodes scapularis. We used image augmentation to further increase the size of our dataset to more than 90,000 images. Here we report the development and validation of a convolutional neural network which we call "TickIDNet," that scores an 87.8% identification accuracy across all three species, outperforming the accuracy of identifications done by a member of the general public or healthcare professionals. However, the model fails to match the performance of experts with formal entomological training. We find that image quality, particularly the size of the tick in the image (measured in pixels), plays a significant role in the network's ability to correctly identify an image: images where the tick is small are less likely to be correctly identified because of the small object detection problem in deep learning. TickIDNet's performance can be increased by using confidence thresholds to introduce an "unsure" class and building image submission pipelines that encourage better quality photos. Our findings suggest that deep learning represents a promising frontier for tick identification that should be further explored and deployed as part of the toolkit for addressing the public health consequences of tick-borne diseases.

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.

Comparative hologenomics of two Ixodes scapularis tick populations in New Jersey

Tick-borne diseases, such as those transmitted by the blacklegged tick Ixodes scapularis, are a significant and growing public health problem in the US. There is mounting evidence that co-occurring non-pathogenic microbes can also impact tick-borne disease transmission. Shotgun metagenome sequencing enables sampling of the complete tick hologenome—the collective genomes of the tick and all of the microbial species contained therein, whether pathogenic, commensal or symbiotic. This approach simultaneously uncovers taxonomic composition and allows the detection of intraspecific genetic variation, making it a useful tool to compare spatial differences across tick populations. We evaluated this approach by comparing hologenome data from two tick samples (N = 6 ticks per location) collected at a relatively fine spatial scale, approximately 23 km apart, within a single US county. Several intriguing variants in the data between the two sites were detected, including polymorphisms in both in the tick’s own mitochondrial DNA and that of a rickettsial endosymbiont. The two samples were broadly similar in terms of the microbial species present, including multiple known tick-borne pathogens (Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum), filarial nematodes, and Wolbachia and Babesia species. We assembled the complete genome of the rickettsial endosymbiont (most likely Rickettsia buchneri) from both populations. Our results provide further evidence for the use of shotgun metagenome sequencing as a tool to compare tick hologenomes and differentiate tick populations across localized spatial scales.

mRNA vaccination induces tick resistance and prevents transmission of the Lyme disease agent

Ixodes scapularis ticks transmit many pathogens that cause human disease, including Borrelia burgdorferi. Acquired resistance to I. scapularis due to repeated tick exposure has the potential to prevent tick-borne infectious diseases, and salivary proteins have been postulated to contribute to this process. We examined the ability of lipid nanoparticle–containing nucleoside-modified mRNAs encoding 19 I. scapularis salivary proteins (19ISP) to enhance the recognition of a tick bite and diminish I. scapularis engorgement on a host and thereby prevent B. burgdorferi infection. Guinea pigs were immunized with a 19ISP mRNA vaccine and subsequently challenged with I. scapularis. Animals administered 19ISP developed erythema at the bite site shortly after ticks began to attach, and these ticks fed poorly, marked by early detachment and decreased engorgement weights. 19ISP immunization also impeded B. burgdorferi transmission in the guinea pigs. The effective induction of local redness early after I. scapularis attachment and the inability of the ticks to take a normal blood meal suggest that 19ISP may be used either alone or in conjunction with traditional pathogen-based vaccines for the prevention of Lyme disease, and potentially other tick-borne infections.

Antibiotic prophylaxis for prevention against Lyme disease following tick bite: an updated systematic review and meta-analysis

Background

In areas where Lyme disease is endemic, bites from ticks are common, but no vaccine is currently available against Lyme disease for humans. Therefore, the feasibility of using antibiotic prophylaxis to prevent Lyme disease after a tick bite is worth further exploration. Previous meta-analyses lack sufficient power to demonstrate the efficacy of about antibiotic prophylaxis for the prevention of Lyme disease following a tick bite. In this study, we explored more precise evidence and attempted to identify and update optimum treatment strategies.

Methods

We searched PubMed, Embase, and the Cochrane Library for studies until March 23, 2021. We included studies if the enrolled patients were randomly allocated to a treatment or control group within 72 h following a tick bite and had no clinical evidence of Lyme disease at enrolment. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were followed for data abstraction. Two authors (GZZ and XX) independently reviewed the abstracts and identified articles for detailed assessment. We used a random-effects model to calculate the pooled results and reported the 95% confidence interval (CI). Study quality was assessed using a modified Jadad scale, and publication bias was assessed using Egger’s test. We calculated the risk ratio (RR) for the rates of unfavorable events in patients who received intervention versus the control group. This study is registered with PROSPERO, number CRD42021245002.

Results

Six studies (3,766 individuals) were included. The pooled rate of unfavorable events in persons receiving treatment and the control group were 0.4% (95%CI: 0.1–1.1%) and 2.2% (95%CI: 1.6–3.0%), respectively. The pooled RR was 0.38 (95%CI: 0.22–0.66). Subgroup analysis revealed that the pooled RR was 0.29 (95%CI: 0.14–0.60) in the single-use 200-mg doxycycline group; 0.28 (95%CI: 0.05–1.67) in a 10-day course group (Amoxicillin, Penicillin or tetracycline); and 0.73 (95%CI: 0.25–2.08) in a topical antibiotic treatment group (Azithromycin).

Conclusions

The available evidence supports the use of antibiotics for the prevention of Lyme disease, and reveals advantages of using single-dose; however, further confirmation is needed.

Patient characteristics, treatment patterns, and outcomes of Rickettsial diseases among a commercially insured population in the United States, 2005-2017

Rickettsial diseases (RDs) are transmitted to humans by ectoparasites, including ticks and fleas. Symptoms range from mild febrile illness, to severe disease or death. Doxycycline is the treatment of choice for patients of all ages; early treatment based on clinical diagnosis is critical to prevent severe outcomes. We conducted a descriptive analysis using insurance claims data captured by IBM MarketScan^® research databases to describe demographics, treatment patterns, and outcomes of patients diagnosed with RDs in the United States during 2005–2017. Overall, 14,830 patients had a RD diagnosis during 2005–2017; 7,517 (50.7%) spotted fever rickettsiosis (SFR), 4,571 ( 30.8%) ehrlichiosis, 1,362 (9.2%) typhus group rickettsiosis (TGR), and 1,193 (8.0%) other rickettsial diseases. Among all patients diagnosed, 53.1% received doxycycline. Prescription rates varied by diagnosis and age; 24.1% of TGR and 61.1% of SFR patients received doxycycline; 23.9% of persons < 8 years received doxycycline, compared with 47.7% for 8–17 years, and 55.4% for ≥ 18 years. RDs are frequently diagnosed in the outpatient population; however, providers prescribed the recommended treatment to about half of patients. Continued education of treatment recommendations is critical to prevent severe outcomes.

Diseases Transmitted by the Black-Legged Ticks in the United States: A Comprehensive Review of the Literature

The black-legged tick is endemic to the midwestern, northeastern, western, south-eastern, and southern regions of the United States. There has been an increased burden of black-legged ticks in humans in recent years. COVID-19 pandemic has further heightened this burden. We thereby reviewed the literature to discuss the seasonality, infections, and clinical spectrum of diseases transmitted by the black-legged ticks. We also discuss the reported delay in the diagnosis of these diseases during the pandemic situation, the alpha-gal syndrome, the importance of prompt diagnosis, and early medical intervention with an aim to increase awareness of the black-legged tick-borne diseases.

Epidemiological Surveillance of Lyme Borreliosis in Bavaria, Germany, 2013-2020

Lyme borreliosis (LB) is the most common tick-borne disease in Germany. Mandatory notification of acute LB manifestations (erythema migrans (EM), neuroborreliosis (NB), and Lyme arthritis (LA)) was implemented in Bavaria on 1 March 2013. We aimed to describe the epidemiological situation and to identify LB risk areas and populations. Therefore, we analyzed LB cases notified from March 2013 to December 2020 and calculated incidence (cases/100,000 inhabitants) by time, place, and person. Overall, 35,458 cases were reported during the study period (EM: 96.7%; NB: 1.7%; LA: 1.8%). The average incidence was 34.3/100,000, but annual incidence varied substantially (2015: 23.2; 2020: 47.4). Marked regional differences at the district level were observed (annual average incidence range: 4–154/100,000). The Bavarian Forest and parts of Franconia were identified as high-risk regions. Additionally, high risk for LB was found in 5–9-year-old males and in 60–69-year-old females. The first group also had the highest risk of a severe disease course. We were able to identify areas and populations in Bavaria with an increased LB risk, thereby providing a basis for targeted measures to prevent LB. Since LB vaccination is currently not available, such measures should comprise (i) avoiding tick bites, (ii) removing ticks rapidly after a bite, and (iii) treating LB early/adequately.

Real-World Assessment of Interferon-β-1b and Interferon-β-1a Adherence Before and After the Introduction of the BETACONNECT® Autoinjector: A Retrospective Cohort Study

BACKGROUND

Both interferon beta-1b (IFN-β-1b) and interferon beta-1a (IFN-β-1a) are immunomodulators that require regular subcutaneous self-administration by patients with multiple sclerosis (MS). However, no electronic autoinjector is available for IFN-β-1a in the US.

OBJECTIVE

This retrospective cohort study investigated adherence to two subcutaneous disease-modifying therapies, IFN-β-1b and IFN-β-1a, during two periods (before and after the introduction of the BETACONNECT® autoinjector for IFN-β-1b).

PATIENTS AND METHODS

Data were evaluated from the MarketScan database for adults in the US with an MS diagnosis and a medical claim for subcutaneous IFN-β-1b or IFN-β-1a, either before (October 2013-September 2015) or after the introduction of BETACONNECT (October 2016-September 2018). Patient populations were propensity-score matched by demographic and clinical characteristics. Persistence was recorded, and adherence was evaluated by medication possession ratio (MPR).

RESULTS

The study included 196 IFN-β-1b and 365 IFN-β-1a people with MS (PwMS) (pre-BETACONNECT period), and 126 IFN-β-1b and 223 IFN-β-1a PwMS (post-BETACONNECT period). In the pre-BETACONNECT period, the proportion with at least 80% MPR was higher for IFN-β-1a (90%) than for IFN-β-1b (83%), but in the post-BETACONNECT period the proportion with ≥ 80% MPR was higher for IFN-β-1b (92%) than for IFN-β-1a (86%). In the pre-BETACONNECT period, median persistence (in days) was higher for IFN-β-1a (199) than for IFN-β-1b (152), while in post-BETACONNECT period persistence was higher for IFN-β-1b (327) than for IFN-β-1a (229).

CONCLUSIONS

Following the introduction of BETACONNECT, this exploratory study suggested that PwMS taking IFN-β-1b were more adherent compared with those taking IFN-β-1a, with higher persistence, and more than 90% reached 80% MPR, a threshold commonly used to define good adherence.

Modeling future climate suitability for the western blacklegged tick, Ixodes pacificus, in California with an emphasis on land access and ownership

In the western United States, Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) is the primary vector of the agents causing Lyme disease and granulocytic anaplasmosis in humans. The geographic distribution of the tick is associated with climatic variables that include temperature, precipitation, and humidity, and biotic factors such as the spatial distribution of its primary vertebrate hosts. Here, we explore (1) how climate change may alter the geographic distribution of I. pacificus in California, USA, during the 21st century, and (2) the spatial overlap among predicted changes in tick habitat suitability, land access, and ownership. Maps of potential future suitability for I. pacificus were generated by applying climate-based species distribution models to a multi-model ensemble of climate change projections for the Representative Concentration Pathway (RCP) 4.5 (moderate emission) and 8.5 (high emission) scenarios for two future periods: mid-century (2026-2045) and end-of-century (2086-2099). Areas climatically-suitable for I. pacificus are projected to expand by 23% (mid-century RCP 4.5) to 86% (end-of-century RCP 8.5) across California, compared to the historical period (1980-2014), with future estimates of total suitable land area ranging from about 88 to 133 thousand km2, or up to about a third of California. Regions projected to have the largest area increases in suitability by end-of-century are in northwestern California and the south central and southern coastal ranges. Over a third of the future suitable habitat is on lands currently designated as open access (i.e. publicly available), and by 2100, the amount of these lands that are suitable habitat for I. pacificus is projected to more than double under the most extreme emissions scenario (from ~23,000 to >51,000 km2). Of this area, most is federally-owned (>45,000 km2). By the end of the century, 26% of all federal land in the state is predicted to be suitable habitat for I. pacificus. The resulting maps may facilitate regional planning and preparedness by informing public health and vector control decision-makers.

A simple method to detect Borrelia burgdorferi sensu lato proteins in different sub-cellular compartments by immunofluorescence

Spirochaetes constitute a unique phylum of bacteria, many of which cause severe clinical diseases. Borrelia burgdorferi sensu lato (B. burgdorferi s.l.)-the primary agent of Lyme borreliosis (LB)-is a quintessential member of this poorly understood phylum and the leading cause of tick-borne illness throughout most of the northern hemisphere. Despite its importance in human health, we lack a fundamental understanding of how B. burgdorferi s.l. is able to accomplish basic physiological tasks, such as DNA replication/segregation, and cell elongation or division. Recent advances in molecular tools to probe these essential cellular processes are great strides forward but require genetic manipulation. The latter is important since not all agents of LB are genetically tractable. Here, we describe a single method that is capable of fluorescently labeling B. burgdorferi s.l. proteins in different sub-cellular compartments. A comparative analysis of six different methods indicates that our optimized procedure outperforms all others and is the first to localize a cytoplasmic protein in B. burgdorferi s.l. by immunofluorescence. We contend that this strategy could be easily adapted to study the localization of any protein, in many Borrelia genospecies, information that will yield functional insights into the complex biology of this fascinating group of bacteria. In addition, it may provide new avenues of research in both in situ studies and in Lyme diagnostics.

Recent Progress in Lyme Disease and Remaining Challenges

Lyme disease (also known as Lyme borreliosis) is the most common vector-borne disease in the United States with an estimated 476,000 cases per year. While historically, the long-term impact of Lyme disease on patients has been controversial, mounting evidence supports the idea that a substantial number of patients experience persistent symptoms following treatment. The research community has largely lacked the necessary funding to properly advance the scientific and clinical understanding of the disease, or to develop and evaluate innovative approaches for prevention, diagnosis, and treatment. Given the many outstanding questions raised into the diagnosis, clinical presentation and treatment of Lyme disease, and the underlying molecular mechanisms that trigger persistent disease, there is an urgent need for more support. This review article summarizes progress over the past 5 years in our understanding of Lyme and tick-borne diseases in the United States and highlights remaining challenges.

Can Diagnostic Codes in Health Care Claims Data Identify Confirmed Chlamydial and Gonococcal Infections? A Retrospective Cohort Study, 2003 to 2017

BACKGROUND

Because most sources of administrative claims data do not contain laboratory result data, researchers rely on diagnosis codes to identify cases of disease. The validity of using diagnosis codes to identify chlamydial and gonococcal infections in administrative claims data remains largely uninvestigated.

METHODS

We conducted a retrospective cohort analysis using OptumLabs Data Warehouse, which includes deidentified medical (inpatient and outpatient) claims and laboratory test results. Among males and females aged 15 to 39 years during the period 2003-2017, we identified chlamydia and gonorrhea test results and corresponding diagnosis codes. Using test results as the criterion standard, we calculated the sensitivity and specificity of chlamydia and gonorrhea diagnosis codes to identify laboratory-confirmed infections.

RESULTS

We identified 9.7 million chlamydia and gonorrhea test results among 3.1 million enrollees. Of the 176,241 positive chlamydia test results, only 11,515 had a corresponding diagnosis code, for a sensitivity of 6.5 (95% confidence interval [CI], 6.4-6.7) and a specificity of 99.5 (95% CI, 99.5-99.5). Corresponding diagnosis codes were identified for 8056 of the 31,766 positive gonorrhea test results, for a sensitivity of 25.4 (95% CI, 24.9-25.8) and a specificity of 99.7 (95% CI, 99.7-99.7).

CONCLUSIONS

Our findings indicate that using only International Classification of Diseases, Ninth and Tenth Revisions, Clinical Modification diagnosis codes to identify chlamydial and gonococcal infections substantially underestimates the burden of these diseases and inaccurately classifies laboratory-confirmed infections.

Epidemiology and Spatial Emergence of Anaplasmosis, New York, USA, 2010‒2018

Human granulocytic anaplasmosis, a tickborne disease caused by the bacterium Anaplasma phagocytophilum, was first identified during 1994 and is now an emerging public health threat in the United States. New York state (NYS) has experienced a recent increase in the incidence of anaplasmosis. We analyzed human case surveillance and tick surveillance data collected by the NYS Department of Health for spatiotemporal patterns of disease emergence. We describe the epidemiology and growing incidence of anaplasmosis cases reported during 2010–2018. Spatial analysis showed an expanding hot spot of anaplasmosis in the Capital Region, where incidence increased >8-fold. The prevalence of A. phagocytophilum increased greatly within tick populations in the Capital Region over the same period, and entomologic risk factors were correlated with disease incidence at a local level. These results indicate that anaplasmosis is rapidly emerging in a geographically focused area of NYS, likely driven by localized changes in exposure risk.

Experience and knowledge of Lyme disease: A scoping review of patient-provider communication

There has been limited research on patient-provider communication dynamics regarding Lyme disease (LD) diagnosis and treatment. Evidence suggests communication in the clinical encounter improves when both patient and healthcare provider (HCP) have concordant orientations (or beliefs) on discussed topics, resulting in higher patient satisfaction and care outcomes. The purpose of this scoping review was to characterize and summarize current research findings on patient and provider knowledge and experiences regarding LD - two factors that may influence the orientation of both patients and providers toward LD in the clinical setting. None of the articles included in the review specifically addressed patient-provider interaction and relationships as the main objective. However, the existing literature indicates notable HCP uncertainty regarding LD diagnosis, treatment, and applied practice patterns. Current research also describes limited knowledge of LD among patient populations and a high prevalence of negative perceptions of care received in mainstream healthcare settings among individuals with persistent symptoms. We identified a critical gap in research that seeks to understand the dynamic of patients and HCPs communicating on the topic of LD in the clinical setting. Future research may identify opportunities where the patient-provider communication dynamic can be improved.

Changing Trends in Age and Sex Distributions of Lyme Disease-United States, 1992-2016

Lyme disease is the most common vector-borne disease in the United States and is characterized by a bimodal age distribution and male predominance. We examined trends in reported cases during a 25-year period to describe changes in the populations most affected by Lyme disease in the United States. We examined demographic characteristics of people with confirmed cases of Lyme disease reported to the Centers for Disease Control and Prevention during 1992-2016 through the National Notifiable Diseases Surveillance System. We grouped cases into 5-year periods (1992-1996, 1997-2001, 2002-2006, 2007-2011, 2012-2016). We calculated the average annual incidence by age and sex and used incidence rate ratios (IRRs) to describe changes in Lyme disease incidence by age and sex over time. We converted patient age at time of illness into patient birth year to ascertain disease patterns according to birth cohorts. The incidence of Lyme disease in the United States doubled from 1992-1996 to 2012-2016 (IRR = 1.74; 95% CI, 1.70-1.78) and increased disproportionately among males; IRRs were 39%-89% higher among males than among females for most age groups. During the study period, children aged 5-9 years were most frequently and consistently affected. In contrast, the average age of adults with Lyme disease increased over time; of all adults, people born during 1950-1964 were the most affected by Lyme disease. Our findings suggest that age-related behaviors and susceptibilities may drive infections among children, and the shifting peak among adults likely reflects a probability proportional to the relative size of the baby boom population. These findings can inform targeted and efficient public health education and intervention efforts.

Vertigo as One of the Symptoms of Lyme Disease

Objectives: The aim of the study was to evaluate the frequency of vertigo symptoms and potential labyrinth damage in patients with diagnosed Lyme disease (LD). LD can affect the vestibulocochlear nerve, leading to hearing loss and vertigo/dizziness. Material and Methods: The study included a group of 38 patients between the ages of 20 and 77, who were hospitalized due to vertigo/dizziness between 2018 and 2019. All of the patients underwent a detailed medical interview and an otolaryngological and neurological examination, including video electronystagmography (VENG), in addition to audiological and diagnostic tests. Additionally, ELISA and Western blot tests were performed to confirm the diagnosis of LD. Results: In 20 patients (53%), the Romberg trial was positive (p < 0.001). The degree of vestibular dysfunction as shown by the VENG test was associated with the rate of hearing loss as confirmed by the Auditory Brainstem Response (ABR) test (p = 0.011), and it mainly concerned high-frequency sounds (p = 0.014). Conclusion: Vertigo can be a symptom of LD. It is often associated with labyrinth and hearing-organ damage, which can imply that the inner ear or nerve VIII is dysfunctional in the course of this disease. Antibiotic therapy is effective in reducing otoneurological symptoms.

Tick-Borne Surveillance Patterns in Perceived Non-Endemic Geographic Areas: Human Tick Encounters and Disease Outcomes

Recent scholarship supports the use of tick bite encounters as a proxy for human disease risk. Extending entomological monitoring, this study was designed to provide geographically salient information on self-reported tick bite encounters by survey respondents who concomitantly reported a Lyme disease (LD) diagnosis in a state perceived as non-endemic to tick-borne illness. Focusing on Texas, a mixed-methods approach was used to compare data on tick bite encounters from self-reported LD patients with county-level confirmed cases of LD from the U.S. Centers for Disease Control and Prevention (CDC), as well as serological canine reports. A greater proportion of respondents reported not recalling a tick bite in the study population, but a binomial test indicated that this difference was not statistically significant. A secondary analysis compared neighboring county-level data and ecological regions. Using multi-layer thematic mapping, our findings indicated that tick bite reports accurately overlapped with the geographic patterns of those patients previously known to be CDC-positive for serological LD and with canine-positive tests for Borrelia burgdorferi, anaplasmosis, and ehrlichiosis, as well as within neighboring counties and ecological regions. LD patient-reported tick bite encounters, corrected for population density, also accurately aligned with official CDC county hot-spots. Given the large number of counties in Texas, these findings are notable. Overall, the study demonstrates that direct, clinically diagnosed patient reports with county-level tick bite encounter data offer important public health surveillance measures, particularly as it pertains to difficult-to-diagnose diseases where testing protocols may not be well established. Further integration of geo-ecological and socio-demographic factors with existing national epidemiological data, as well as increasingly accessible self-report methods such as online surveys, will contribute to the contextual information needed to organize and implement a coordinated public health response to LD.

Visualizing Borrelia burgdorferi Infection Using a Small-Molecule Imaging Probe

In vivo diagnostic imaging of bacterial infections is currently reliant on targeting their metabolic pathways, an ineffective method to identify microbial species with low metabolic activity. Here, we establish HS-198 as a small-molecule fluorescent conjugate that selectively targets the highly conserved bacterial protein HtpG (high-temperature protein G), within Borrelia burgdorferi, the bacterium responsible for Lyme disease. We describe the use of HS-198 to target morphologic forms of B. burgdorferi in both the logarithmic growth phase and the metabolically dormant stationary phase as well as in inactivated spirochetes. Furthermore, in a murine infection model, systemically injected HS-198 identified B. burgdorferi as revealed by imaging in postnecropsy tissue sections. These findings demonstrate how small-molecule probes directed at conserved bacterial protein targets can function to identify the microbe using noninvasive imaging and potentially as scaffolds to deliver antimicrobial agents to the pathogen.

Atypical Manifestations of Cat-Scratch Disease, United States, 2005-2014

Atypical manifestations that can be severe and difficult to diagnosis develop in 5%-20% of patients with cat-scratch disease. To clarify the epidemiology of atypical cat-scratch disease in the United States, we analyzed data from the 2005-2014 MarketScan national health insurance claims databases by using the International Classification of Diseases, 9th Revision, Clinical Modification, codes for cat-scratch disease and selected atypical manifestations: retinitis/neuroretinitis, conjunctivitis, neuritis, encephalitis, hepatosplenic disease, osteomyelitis, erythema nodosum, and endocarditis. Atypical cat-scratch disease accounted for 1.5% of all cases, resulting in an average annual incidence of 0.7 cases/100,000 population. Atypical cat-scratch disease was associated with increased risk for hospitalization (risk ratios 8.77, 95% CI 6.56-11.72) and occurred most often in female patients 10-14 years of age. Ocular (48.7%), hepatosplenic (24.6%), and neurologic (13.8%) manifestations were most common among patients. A more comprehensive understanding of atypical cat-scratch disease can improve patient diagnosis and potentially elucidate pathophysiology of the disease.

Estimating the Frequency of Lyme Disease Diagnoses, United States, 2010-2018

By using commercial insurance claims data, we estimated that Lyme disease was diagnosed and treated in ≈476,000 patients in the United States annually during 2010–2018. Our results underscore the need for accurate diagnosis and improved prevention.

Lyme disease in Western Europe: an emerging problem? A systematic review

Objectives: Lyme borreliosis is the most common zoonotic disease in Europe and causes an estimated total burden of 10.55 disability-adjusted life years (DALY) per 100 000 population. Its incidence in Western Europe is assumed to be increasing, yet this remains to be confirmed. The aim of this study was to assess the emergence of Lyme disease in Western Europe by performing a systematic review of the scientific literature.Methods: Pubmed, Embase and grey literature were searched from database inception until August 2018 for articles reporting the incidence of Lyme borreliosis in Western European countries. We included observational studies in English that reported data on a random sample of the population and fulfilled our definition of Lyme disease diagnosis. Annual population-weighted averages and the evolution of Lyme borreliosis incidence were extracted or calculated for every Western European country.Results: Our review identified 1514 and included 18 studies next to seven surveillance reports reporting data from 16 Western European countries. Incidence of Lyme borreliosis ranged from 0.001 (Italy) to 632 (Sweden, Blekinge county) cases/100 000/year. Iceland reported the strongest emergence with an average yearly increase of 21.15% over a 12-year period, whereas Italy reported the strongest average yearly decrease of 52.71% over a 5-year period. Very limited high-quality data were available on Lyme borreliosis incidence in the southern Western European countries.Conclusion: Diagnosis of Lyme borreliosis is on the rise in some Western European countries, mostly in the northern and central part. Better surveillance in the southern countries is necessary.

A Framework for the Eltonian Niche of Humans

Recent research has highlighted several influential roles that humans play in ecosystems, including that of a superpredator, hyperkeystone species, and niche constructor. This work has begun to describe the Eltonian niche of humans, which encompasses humanity's cumulative ecological and evolutionary roles in trophic systems. However, we lack a unifying framework that brings together these strands of research, links them to ecoevolutionary and sociocultural theory, and identifies current research needs. In this article, we present such a framework in hope of facilitating a more holistic approach to operationalizing human roles in trophic systems across an increasingly anthropogenic biosphere. The framework underscores how humans play numerous nuanced roles in trophic systems, from top-down to bottom-up, that entail not only pernicious effects but also benefits for many nonhuman species. Such a nuanced view of the Eltonian niche of humans is important for understanding complex social–ecological system functioning and enacting effective policies and conservation measures.

Sexual Transmission of Lyme Borreliosis? The Question That Calls for an Answer

Transmission of the causative agents of numerous infectious diseases might be potentially conducted by various routes if this is supported by the genetics of the pathogen. Various transmission modes occur in related pathogens, reflecting a complex process that is specific for each particular host-pathogen system that relies on and is affected by pathogen and host genetics and ecology, ensuring the epidemiological spread of the pathogen. The recent dramatic rise in diagnosed cases of Lyme borreliosis might be due to several factors: the shifting of the distributional range of tick vectors caused by climate change; dispersal of infected ticks due to host animal migration; recent urbanization; an increasing overlap of humans' habitat with wildlife reservoirs and the environment of tick vectors of Borrelia; improvements in disease diagnosis; or establishment of adequate surveillance. The involvement of other bloodsucking arthropod vectors and/or other routes of transmission (human-to-human) of the causative agent of Lyme borreliosis, the spirochetes from the Borrelia burgdorferi sensu lato complex, has been speculated to be contributing to increased disease burden. It does not matter how controversial the idea of vector-free spirochete transmission might seem in the beginning. As long as evidence of sexual transmission of Borrelia burgdorferi both between vertebrate hosts and between tick vectors exists, this question must be addressed. In order to confirm or refute the existence of this phenomenon, which could have important implications for Lyme borreliosis epidemiology, the need of extensive research is obvious and required.

Dynamics of data availability in disease modeling: An example evaluating the trade-offs of ultra-fine-scale factors applied to human West Nile virus disease models in the Chicago area, USA

Background

Since 1999, West Nile virus (WNV) has moved rapidly across the United States, resulting in tens of thousands of human cases. Both the number of human cases and the minimum infection rate (MIR) in vector mosquitoes vary across time and space and are driven by numerous abiotic and biotic forces, ranging from differences in microclimates to socio-demographic factors. Because the interactions among these multiple factors affect the locally variable risk of WNV illness, it has been especially difficult to model human disease risk across varying spatial and temporal scales. Cook and DuPage Counties, comprising the city of Chicago and surrounding suburbs, experience some of the highest numbers of human neuroinvasive cases of WNV in the United States. Despite active mosquito control efforts, there is consistent annual WNV presence, resulting in more than 285 confirmed WNV human cases and 20 deaths from the years 2014–2018 in Cook County alone.

Methods

A previous Chicago-area WNV model identified the fifty-five most high and low risk locations in the Northwest Mosquito Abatement District (NWMAD), an enclave ¼ the size of the combined Cook and DuPage county area. In these locations, human WNV risk was stratified by model performance, as indicated by differences in studentized residuals. Within these areas, an additional two-years of field collections and data processing was added to a 12-year WNV dataset that includes human cases, MIR, vector abundance, and land-use, historical climate, and socio-economic and demographic variables, and was assessed by an ultra-fine-scale (1 km spatial x 1 week temporal resolution) multivariate logistic regression model.

Results

Multivariate statistical methods applied to the ultra-fine-scale model identified fewer explanatory variables while improving upon the fit of the previous model. Beyond MIR and climatic factors, efforts to acquire additional covariates only slightly improved model predictive performance.

Conclusions

These results suggest human WNV illness in the Chicago area may be associated with fewer, but increasingly critical, key variables at finer scales. Given limited resources, these findings suggest large variations in model performance occur, depending on covariate availability, and provide guidance in variable selection for optimal WNV human illness modeling.

Monitoring the patterns of submission and presence of tick-borne pathogens in Ixodes scapularis collected from humans and companion animals in Ontario, Canada (2011-2017)

BACKGROUND

The universal nature of the human-companion animal relationship and their shared ticks and tick-borne pathogens offers an opportunity for improving public and veterinary health surveillance. With this in mind, we describe the spatiotemporal trends for blacklegged tick (Ixodes scapularis) submissions from humans and companion animals in Ontario, along with pathogen prevalence.

METHODS

We tested tick samples submitted through passive surveillance (2011-2017) from humans and companion animals for Borrelia burgdorferi, Borrelia miyamotoi, Anaplasma phagocytophilum and Babesia microti. We describe pathogen prevalence in ticks from humans and from companion animals and constructed univariable Poisson and negative binomial regression models to explore the spatiotemporal relationship between the rates of tick submissions by host type.

RESULTS

During the study, there were 17,230 blacklegged tick samples submitted from humans and 4375 from companion animals. Tick submission rates from companion animals were higher than expected in several public health units (PHUs) lacking established tick populations, potentially indicating newly emerging populations. Pathogen prevalence in ticks was higher in PHUs where established blacklegged tick populations exist. Borrelia burgdorferi prevalence was higher in ticks collected from humans (maximum likelihood estimate, MLE = 17.5%; 95% confidence interval, CI 16.97-18.09%) than from companion animals (9.9%, 95% CI 9.15-10.78%). There was no difference in pathogen prevalence in ticks by host type for the remaining pathogens, which were found in less than 1% of tested ticks. The most common co-infection B. burgdorferi + B. miyamotoi occurred in 0.11% of blacklegged ticks from humans and animals combined. Borrelia burgdorferi prevalence was higher in unengorged (21.9%, 95% CI 21.12-22.65%) than engorged ticks (10.0%, 95% CI 9.45-10.56%). There were no consistent and significant spatiotemporal relationships detected via regression models between the annual rates of submission of each host type.

CONCLUSIONS

While B. burgdorferi has been present in blacklegged ticks in Ontario for several decades, other tick-borne pathogens are also present at low prevalence. Blacklegged tick and pathogen surveillance data can be used to monitor risk in human and companion animal populations, and efforts are under consideration to unite surveillance efforts for the different target populations.

Doxycycline for Prevention of Spirochetal Infections: Status Report

Important human infections caused by spirochetal microorganisms include Lyme disease, syphilis, leptospirosis, and tick-borne relapsing fever. Doxycycline prophylactic regimens have been shown to significantly reduce the risk for developing all of these infections in potentially exposed individuals, which is highly clinically relevant as no vaccines to prevent these infections in humans are currently available. Additional data, however, are needed to define more precisely the level of efficacy of the doxycycline prophylactic regimens, especially for Lyme disease and syphilis, infections that can be potentially prevented by a single 200-mg dose of doxycycline given within 72 hours postexposure.

Microfluidic Assays for Probing Neutrophil-Borrelia Interactions in Blood During Lyme Disease

Human neutrophils are highly sensitive to the presence of Borrelia burgdorferi (Bb), the agent of Lyme disease (LD), in tissues. Although Bb is also found in the blood of LD patients, far less is known about how neutrophils respond to Bb in the presence of blood. In this study, we employed microfluidic tools to probe the interaction between human neutrophils and Bb and measured the activation of human neutrophils in blood samples from patients. We found that neutrophils migrate vigorously toward Bb in the presence of serum, and this process was complement-dependent. Preventing complement factor 5 cleavage or blocking complement receptors decreased neutrophil's ability to interact with Bb. We also found that spiking Bb directly into the blood from healthy donors induced spontaneous neutrophil motility. This response to Bb was also complement-dependent. Preventing complement factor 5 cleavage decreased spontaneous neutrophil motility in Bb-spiked blood. Moreover, we found that neutrophils in blood samples from acute LD patients displayed spontaneous motility patterns similar to those observed in Bb-spiked samples. Neutrophil motility was more robust in blood samples from LD patients than that measured in healthy and ill controls, validating the utility of the microfluidic assay for the study of neutrophil-Bb interactions in the presence of blood.

An Epidemiological Survey Regarding Ticks and Tick-Borne Diseases among Livestock Owners in Punjab, Pakistan: A One Health Context

Recent global changes have led to an increase in the spread of ticks and tick-borne diseases (TBDs) affecting domestic ruminants and humans, with an annual loss of US $13.9–$18.7 billion. The current study determined the perception and practices of livestock farmers regarding tick infestation. A total of 112 livestock farms were surveyed in Punjab, Pakistan, among which animals from 42 (37.5%) farms were infested with ticks. Only 28.6% (n = 32) of the dairy farmers were consulting veterinarians for ticks control, while 86.7% (n = 97) of the respondents did not consider biosecurity measures in the control of tick transmission. Most of the respondents, 71.4% (n = 80), did not consider manual tick removal from their animals (i.e., by hand, followed by physically crushing) as a risky practice for spreading zoonotic diseases. Improper disposal of bottles of acaricides in the farm drainage was also observed, putting the environment and aquatic life at risk. These wrong practices may contribute to high disease burdens and economic losses, increasing the possibility of transmission of zoonotic TBDs and pollution of the environment. Therefore, an integrated One Health approach is required for the control of TBDs through environmentally friendly approaches.

Do-It-Yourself Tick Control: Granular Gamma-Cyhalothrin Reduces Ixodes scapularis (Acari: Ixodidae) Nymphs in Residential Backyards

Lyme disease is the most common vector-borne disease in the United States with hotspots in the Northeast and Midwest. Integrated vector control for mosquito-borne disease prevention is often organized at the community level, but tick control is primarily coordinated at the household and individual level. Management of the blacklegged tick, Ixodes scapularis (Say), the vector of the causative agent of Lyme disease in the Midwest and eastern United States in peridomestic environments may be critical as many tick encounters are reported to occur in the yard. Therefore, we assessed the effectiveness of a widely available and low-cost pesticide that targets common lawn pests and is labeled for use against ticks. In June 2019, we evaluated a granular form of gamma-cyhalothrin in a placebo-controlled residential backyard study (n = 90) in two communities in Wisconsin. The product applied by the research team reduced nymphal blacklegged ticks in plots established in the lawn part of the ecotone by 97% one week after application at both communities and by 89-97% three to four weeks postapplication. The proportion of homes with at least one nymphal tick postapplication was significantly lower at acaricide-treated homes and ranged from 4.2 to 29.2% compared with placebo homes where at least one nymphal tick was found at 50-81.5% of homes. These results support the efficacy of a low-cost do-it-yourself strategy for homeowners seeking to reduce blacklegged ticks in the yard.

Willingness to Pay for Select Tick-Borne Disease Prevention Measures in Endemic Areas

Tick-borne diseases (TBDs) are increasing despite prevention recommendations. We explored whether cost is a barrier to prevention use in Connecticut and Maryland, using a cross-sectional survey. Respondents were queried regarding their willingness to pay for chemical, natural, and rodent-targeted yard pesticide treatments and permethrin-treated clothing. We evaluated associations between demographics, TBD knowledge and attitudes, and willingness to pay for prevention methods. Most respondents would pay for yard treatments (85%); 95% preferring natural pesticide, and 82% would pay for permethrin-treated clothing. Most did not want to pay more than $99 for any of the yard treatments. Having a household income of $100 000 was associated with willingness to pay $100 or more for chemical, natural, or rodent-targeted treatments and $25 or more for permethrin self-treated and pretreated clothing. Yard treatments, especially natural pesticides, were acceptable for TBD prevention; however, current pricing may be cost-prohibitive. Permethrin-treated clothing may be an affordable and acceptable prevention method.

Assessing Recognition of the Vector of Lyme Disease Using Resin-Embedded Specimens in a Lyme Endemic Area

Lyme disease (LD) is the most common vector-borne disease in the United States. To assess whether a tick bite puts someone at risk for LD, adequate tick identification skills are needed. We surveyed residents of a high LD-incidence state, Wisconsin, on their ability to distinguish ticks from insects and to identify the specimens that could transmit the LD causative agent. Surveys were conducted using resin blocks with four insects and four tick specimens embedded. About half of the participants (64 of 130) recognized all of the ticks, and 60% of those individuals chose only ticks and no insects. Younger participants (18- to 44-yr old) were more likely to identify ticks correctly compared with those 45 yr and older. Participants who agreed strongly with the statement 'I know a lot about ticks` were also likelier to correctly identify ticks. When asked to identify which specimens could transmit LD, less than 25% of participants chose both the Ixodes scapularis Say adult female and nymph and about half of those (15% of participants) picked only those two and no other specimens. Although the relatively small convenience sample was biased toward younger participants who consider themselves 'outdoorsy', results showed that further assessments of tick recognition skills are needed to understand what determines whether people can recognize medically important ticks and to evaluate the potential benefits of enhanced education. In addition to the value of the resin blocks as research tools, the blocks may be useful as training tools to improve tick check efficacy.

Predicting Lyme Disease From Patients' Peripheral Blood Mononuclear Cells Profiled With RNA-Sequencing

Although widely prevalent, Lyme disease is still under-diagnosed and misunderstood. Here we followed 73 acute Lyme disease patients and uninfected controls over a period of a year. At each visit, RNA-sequencing was applied to profile patients' peripheral blood mononuclear cells in addition to extensive clinical phenotyping. Based on the projection of the RNA-seq data into lower dimensions, we observe that the cases are separated from controls, and almost all cases never return to cluster with the controls over time. Enrichment analysis of the differentially expressed genes between clusters identifies up-regulation of immune response genes. This observation is also supported by deconvolution analysis to identify the changes in cell type composition due to Lyme disease infection. Importantly, we developed several machine learning classifiers that attempt to perform various Lyme disease classifications. We show that Lyme patients can be distinguished from the controls as well as from COVID-19 patients, but classification was not successful in distinguishing those patients with early Lyme disease cases that would advance to develop post-treatment persistent symptoms.

Diagnosis, Treatment, and Prevention Practices for Lyme Disease by Clinicians, United States, 2013-2015

OBJECTIVES

Although tick-borne diseases account for a large number of health care visits in the United States, clinical practices for tick bite and Lyme disease treatment and prevention are not well understood. The objective of this study was to better understand factors associated with clinical practices related to tick bites and Lyme disease.

METHODS

In 2013-2015, questions about tick-bite evaluation, Lyme disease diagnosis and treatment, appropriate use of Lyme disease testing, and tick-bite prevention were included in Porter Novelli's DocStyles survey, a nationally representative annual web-based survey of health care providers. We performed analyses of responses by provider license type and state-level incidence (high or low) of Lyme disease in 2019.

RESULTS

A total of 4517 providers were surveyed across the 3 study years. Overall, 80.9% of providers reported that they had evaluated at least 1 patient for a tick bite, 47.6% had diagnosed at least 1 patient with Lyme disease, and 61.9% had treated at least 1 patient for Lyme disease in the previous year. Providers from states with a high incidence of Lyme disease saw more patients for tick bites and Lyme disease than providers from states with a low incidence of Lyme disease. Few providers correctly chose Lyme disease testing as clinically useful in the hypothetical case of a patient from a state with a high incidence of Lyme disease with an arthritic knee (36.0%) or with new-onset atrioventricular block (39.5%), and respondents across all provider types incorrectly chose testing when not clinically indicated. Most providers (69.7%) reported routinely recommending tick-bite prevention methods to patients.

CONCLUSIONS

Many providers evaluate patients for tick bites and treat patients for Lyme disease, but knowledge about appropriate testing is low. Providers may benefit from tailored education about appropriate Lyme disease diagnosis, testing, and effective tick-bite prevention.

Epidemiology and cost of Lyme disease-related hospitalizations among patients with employer-sponsored health insurance-United States, 2005-2014

An estimated 300,000 cases of Lyme disease occur in the United States annually. Disseminated Lyme disease may result in carditis, arthritis, facial palsy or meningitis, sometimes requiring hospitalization. We describe the epidemiology and cost of Lyme disease-related hospitalizations. We analysed 2005-2014 data from the Truven Health Analytics MarketScan Commercial Claims and Encounters Databases to identify inpatient records associated with Lyme disease based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. We estimated the annual number and median cost of Lyme disease-related hospitalizations in the United States in persons under 65 years of age. Costs were adjusted to reflect 2016 dollars. Of 20,983,165 admission records contained in the inpatient databases during the study period, 2,823 (0.01%) met inclusion criteria for Lyme disease-related hospitalizations. Over half of the identified records contained an ICD-9-CM code for meningitis (n = 614), carditis (n = 429), facial palsy (n = 400) or arthritis (n = 377). Nearly 60% of hospitalized patients were male. The median cost per Lyme disease-related hospitalization was $11,688 (range: $140-$323,613). The manifestation with the highest median cost per stay was carditis ($17,461), followed by meningitis ($15,177), arthritis ($13,012) and facial palsy ($10,491). Median cost was highest among the 15- to 19-year-old age group ($12,991). Admissions occurring in January had the highest median cost ($13,777) for all study years. Based on extrapolation to the U.S. population, we estimate that 2,196 Lyme disease-related hospitalizations in persons under 65 years of age occur annually with an estimated annual cost of $25,826,237. Lyme disease is usually treated in an outpatient setting; however, some patients with Lyme disease require hospitalization, underscoring the need for effective prevention methods to mitigate these serious cases. Information from this analysis can aid economic evaluations of interventions that prevent infection and advances in disease detection.

Lyme disease: diagnosis and treatment

PURPOSE OF REVIEW

Lyme disease is an important, vector-borne infection found throughout the temperate Northern hemisphere. The disease causes rash, acute systemic illness, and in some untreated patients, inflammatory arthritis. This review examines the emergence, clinical features and management of early Lyme disease and Lyme arthritis.

RECENT FINDINGS

There has been continuing progress in characterizing the clinical manifestations, diagnostic testing and treatment of Lyme disease. Almost all patients with early Lyme disease can be cured with antibiotic treatment. In most cases, Lyme arthritis also responds to antibiotics, but some patients require additional treatment approaches.

SUMMARY

The diagnosis of Lyme disease is based on clinical manifestations and adjunctive laboratory testing. For the rheumatologist, Lyme arthritis should be recognized by a pattern of attacks of asymmetric, oligo-arthritis, recognizable by clinical manifestations in the same way that other rheumatic diseases, such as gout or rheumatoid arthritis, are diagnosed.

AC-DC electropenetrography unmasks fine temporal details of feeding behaviors for two tick species on unsedated hosts

Ticks are significant nuisance pests and vectors of pathogens for humans, companion animals, and livestock. Limited information on tick feeding behaviors hampers development and rigorous evaluation of tick and tick-borne pathogen control measures. To address this obstacle, the present study examined the utility of AC–DC electropenetrography (EPG) to monitor feeding behaviors of adult Dermacentor variabilis and Amblyomma americanum in real-time. EPG recording was performed during early stages of slow-phase tick feeding using an awake calf host. Both tick species exhibited discernable and stereotypical waveforms of low-, medium-, and high-frequencies. Similar waveform families and types were observed for both tick species; however, species-specific waveform structural differences were also observed. Tick waveforms were hierarchically categorized into three families containing seven types. Some waveform types were conserved by both species (e.g., Types 1b, 1c, 2b, 2c) while others were variably performed among species and individually recorded ticks (e.g., Types 1a, 2a, 2d). This study provides a proof-of-principle demonstration of the feasibility for using EPG to monitor, evaluate, and compare tick feeding behaviors, providing a foundation for future studies aimed at correlating specific feeding behaviors with waveforms, and ultimately the influence of control measures and pathogens on tick feeding behaviors.

Borrelia burgdorferi infection induces long-term memory-like responses in macrophages with tissue-wide consequences in the heart

Lyme carditis is an extracutaneous manifestation of Lyme disease characterized by episodes of atrioventricular block of varying degrees and additional, less reported cardiomyopathies. The molecular changes associated with the response to Borrelia burgdorferi over the course of infection are poorly understood. Here, we identify broad transcriptomic and proteomic changes in the heart during infection that reveal a profound down-regulation of mitochondrial components. We also describe the long-term functional modulation of macrophages exposed to live bacteria, characterized by an augmented glycolytic output, increased spirochetal binding and internalization, and reduced inflammatory responses. In vitro, glycolysis inhibition reduces the production of tumor necrosis factor (TNF) by memory macrophages, whereas in vivo, it produces the reversion of the memory phenotype, the recovery of tissue mitochondrial components, and decreased inflammation and spirochetal burdens. These results show that B. burgdorferi induces long-term, memory-like responses in macrophages with tissue-wide consequences that are amenable to be manipulated in vivo.

Lyme carditis is a manifestation of Lyme disease characterized by episodes of atrioventricular block and additional cardiomyopathies. This study describes the proteomic and transcriptomic changes in the heart upon infection with Borrelia burgdorferi, and identifies innate immune memory hallmarks specific to the response to the spirochete that are amenable to therapeutic manipulation.

Experiences with tick exposure, Lyme disease, and use of personal prevention methods for tick bites among members of the U.S. population, 2013-2015

Consistent and effective use of personal prevention methods for tickborne diseases, including Lyme disease (LD), is dependent on risk awareness. To improve our understanding of the general U.S. population's experiences with tick exposure and use of personal prevention methods, we used data from ConsumerStyles, a web-based, nationally representative questionnaire on health-related topics. Questions addressed tick bites and LD diagnosis in the last year, use of personal prevention methods to prevent tick bites, and willingness to receive a theoretical LD vaccine. Of 10,551 participants surveyed over three years, 12.3 % reported a tick bite for themselves or a household member in the last year, including 15.4 % of participants in high LD incidence (LDI) states, 16.3 % in states neighboring high LDI states, and 9.4 % in low LDI states. Participants in high LDI states and neighboring states were most likely to use personal prevention methods, though 46.6 % of participants in high LDI states and 53.9 % in neighboring states reported not using any method. Participants in low LDI states, adults ≥ 75 years of age, those with higher incomes, and those living in urban housing tended to be less likely to practice personal prevention methods. Likeliness to receive a theoretical LD vaccine was high in high LDI (64.5 %), neighboring (52.5 %), and low LDI (49.7 %) states. Targeted educational efforts are needed to ensure those in high LDI and neighboring states, particularly older adults, are aware of their risk of LD and recommended personal prevention methods.

Use of Commercial Claims Data for Evaluating Trends in Lyme Disease Diagnoses, United States, 2010-2018

We evaluated MarketScan, a large commercial insurance claims database, for its potential use as a stable and consistent source of information on Lyme disease diagnoses in the United States. The age, sex, and geographic composition of the enrolled population during 2010-2018 remained proportionally stable, despite fluctuations in the number of enrollees. Annual incidence of Lyme disease diagnoses per 100,000 enrollees ranged from 49 to 88, ≈6-8 times higher than that observed for cases reported through notifiable disease surveillance. Age and sex distributions among Lyme disease diagnoses in MarketScan were similar to those of cases reported through surveillance, but proportionally more diagnoses occurred outside of peak summer months, among female enrollees, and outside high-incidence states. Misdiagnoses, particularly in low-incidence states, may account for some of the observed epidemiologic differences. Commercial claims provide a stable data source to monitor trends in Lyme disease diagnoses, but certain important characteristics warrant further investigation.

Aggregation of data from 4 clinical studies demonstrating efficacy of single-dose doxycycline postexposure for prevention of the spirochetal infections: Lyme disease, syphilis, and tick-borne relapsing fever

Single-dose doxycycline, given within 72 hours of exposure, has been evaluated in 4 clinical studies for postexposure prophylaxis of 3 spirochetal infections: Lyme disease, syphilis, and tick-borne relapsing fever. In this study, data from the 4 studies were aggregated using a meta-analytic random-effects approach, with the DerSimonian-Laird method for variance estimation, analyzing a total of 2468 subjects. The findings of this analysis demonstrated an overall efficacy rate for prevention of the 3 spirochetal infections of 78% (95% confidence interval: 50%-91%).