Insights From the Geographic Spread of the Lyme Disease Epidemic

MRI features distinguishing pediatric Lyme arthritis from septic arthritis

OBJECTIVE

This study aims to identify distinguishing MRI features of Lyme arthritis (LA), an increasingly prevalent cause of pediatric infectious arthritis in the USA, to enable rapid discrimination from septic arthritis (SA) and facilitate appropriate management.

MATERIALS AND METHODS

A single-center, retrospective analysis was conducted on a convenience sample of pediatric patients with LA in an endemic area using EPIC electronic health record data between January 2010 and December 2020. Patients with positive serologic testing and concurrent MRI were selected. MRI scans were reviewed by a subspecialty-trained pediatric radiologist. Key MRI features analyzed include joint effusion, synovitis, myositis, soft tissue edema, and osseous edema and erosions. MRI features, demographics, and clinical data were compared using univariable and multivariable analyses.

RESULTS

Fifty cases of knee LA and 13 cases of knee SA were included. Larger joint effusion (p = 0.0055, z =  - 2.779) and abnormally thickened synovium (p = 0.0011, χ2 = 10.622) were more associated with LA. In contrast, increased myositis, subcutaneous edema, and osseous changes were more prevalent in SA. Abnormal bone marrow signal (p < 0.0001, χ2 = 36.893) and bone erosion (p < 0.0001, χ2 = 25.506) were observed in 84.6% (11/13) and 46.2% (6/13) of SA cases, respectively, while no bone erosion was found in LA.

CONCLUSION

MRI can be a valuable tool in differentiating LA from SA. Abnormal synovium and increasing joint effusion favor LA, while increasing soft tissue edema and osseous changes favor SA. Notably, the presence of bone erosion effectively excluded LA from consideration.

Climate-induced expansion of Lyme disease in east central Ohio

The geographical distribution of Lyme disease has been attributed to changes in Earth's climate and associated distribution of its vector, ticks of the genus Ixodes. This study focuses on the impact of climatic and meteorological conditions on Lyme disease transmission in East Central Ohio, an emerging hotspot of cases. Using county-level data from 2001 to 2023, we analyzed the relationship between Lyme disease cases and temperature, precipitation, and the Southern Oscillation Index (SOI) using a distributed lag nonlinear model (DLNM). Results show that warmer winter temperatures, higher precipitation, and negative SOI values (El Niño conditions) were significantly associated with increased Lyme disease incidence and displayed delayed effects of 6 to18 months. These findings suggest that climate change, with its potential to bring milder winters and increased spring and summer rainfall, may further exacerbate Lyme disease cases in Ohio.

The Acari Hypothesis, IV: revisiting the role of hygiene in allergy

Allergy and its manifestations were first appreciated in the 1870 s. Today, the mechanism by which specific substances elicit allergic reactions remains poorly understood. This is problematic from a healthcare perspective because the prevalence of allergic disease and its societal costs are substantial. Regarding mechanistic understanding of allergy, a new proposal, The Acari Hypothesis, has been forwarded. The Hypothesis, borne from consideration of alpha-gal syndrome, postulates that acarians, i.e., mites and ticks, are operative agents of allergy. By way of their pathogenic payloads and salivary pattern recognition receptor(s), acarians potentiate in human hosts the generation of IgE against acarian dietary elements. Those elements account for most, if not all, known human allergens. Inasmuch as acarian-human interactions occur on human epithelial surfaces, it is to be expected factors that influence the presence and/or operation of acarians on those surfaces influence the expression of allergic diseases. In this report, it is proposed that two adaptations of catarrhine primates, i.e., Old World monkeys, apes and humans, evolved to deter acarian species: firstly, the expansion of eccrine glands across the entirety of body surface area, and, secondly, the secretion of sweat by those glands. Contemporary hygienic practices that reduce and/or disrupt the operation of eccrine glands are likely responsible for the increase in allergic disease seen today.

Lactate Dehydrogenase Inhibitors Suppress Borrelia burgdorferi Growth In Vitro

Borrelia burgdorferi, the causative agent of Lyme disease, has a highly reduced genome and relies heavily on glycolysis for carbon metabolism. As such, established inhibitors of lactate dehydrogenase (LDH) were evaluated in cultures to determine the extent of their impacts on B. burgdorferi growth. Both racemic and enantiopure (AT-101) gossypol, as well as oxamate, galloflavin, and stiripentol, caused the dose-dependent suppression of B. burgdorferi growth in vitro. Racemic gossypol and AT-101 were shown to fully inhibit spirochetal growth at concentrations of 70.5 and 187.5 μM, respectively. Differences between racemic gossypol and AT-101 efficacy may indicate that the dextrorotatory enantiomer of gossypol is a more effective inhibitor of B. burgdorferi growth than the levorotatory enantiomer. As a whole, LDH inhibition appears to be a promising mechanism for suppressing Borrelia growth, particularly with bulky LDH inhibitors like gossypol.

Bilateral Knee Lyme Arthritis in Children: A Report of 3 Cases

CASES

Three patients presented with bilateral knee pain, effusion, decreased range of motion, and difficulty ambulating. Synovial analysis demonstrated leukocytosis in bilateral knees with positive serum enzyme-linked immunosorbent assay. All cases were managed with antibiotics and anti-inflammatories. One patient developed chronic Lyme arthritis and underwent arthroscopic synovectomy.

CONCLUSION

Bilateral knee arthritis is a possible presentation of Lyme disease in children. Accurate diagnosis and treatment with antibiotics and anti-inflammatories can lead to satisfactory outcomes. Arthroscopic synovectomy may be indicated if conservative treatment fails.

Improving Lyme disease testing with data driven test design in pediatrics

Diagnostic advances have not kept pace with the expansion of Lyme disease caused by Borrelia burgdorferi and transmitted by ticks. Lyme disease clinical manifestations can overlap with many other diagnoses making Lyme disease a critical part of many differential diagnoses in endemic areas. Current diagnostic blood tests rely on a 2-tiered algorithm for which the second step is either a time-consuming western blot or a whole cell lysate immunoassay. Neither of these second step tests allow for rapid results of this critical rule out test. We hypothesized that using western blot confirmation information, we could create computational models to propose recombinant second-tier tests that would allow for more rapid, automated, and specific testing algorithms. We propose here a framework for assessing retrospective data to determine putative recombinant assay components. A retrospective pediatric cohort of 2755 samples submitted for Lyme disease screening was assessed using support vector machine learning algorithms to optimize tier 1 diagnostic thresholds for the Vidas IgG II assay and determine optimal tier 2 components for both a positive and negative confirmation test. In cases where the tier 1 screen was negative, but clinical suspicion was high, we found that 1 protein (L58) could be used to reduce false-negative results. For second-tier testing of screen positive cases, we found that 6 proteins could be used to reduce false-positive results (L18, L39M, L39, L41, L45, and L58) with a final machine learning classifier or 2 proteins using a final rules-based approach (L41, L18). This led to an overall accuracy of 92.36% for the proposed algorithm without a final machine learning classifier and 92.12% with integration of the machine learning classifier in the final algorithm when compared to the IgG western blot as the gold-standard. Use of this framework across multiple assays and institutions will allow for a data-driven approach to assay development to provide laboratories and patients with the improvements in turnaround time needed for this testing.

The Impact of Operative Intervention in Pediatric Lyme Arthritis

BACKGROUND

Lyme arthritis often presents as acute monoarticular arthritis challenging to distinguish from septic arthritis. Typical management for Lyme arthritis entails antibiotic therapy, while septic arthritis usually warrants operative debridement. During the period when Western Pennsylvania transitioned to a Lyme-endemic region, many children underwent operative intervention who were ultimately diagnosed with Lyme arthritis due to diagnostic ambiguity. We examined the impact of the operative intervention on pediatric Lyme arthritis outcomes.

METHODS

We conducted a retrospective cohort study of patients admitted to a tertiary care children's hospital who were diagnosed with Lyme arthritis from 2008 to 2018 using chart review. Inclusion criteria were positive Lyme serology by Centers for Disease Control and Prevention (CDC) definition, clinical arthritis, and negative bacterial cultures. We recorded clinical presentation, laboratory data, details of hospitalization, costs, and outcomes after therapy to compare the impact of antibiotics alone (nonoperative group) versus antibiotics plus operative debridement (operative group).

RESULTS

A total of 149 patients met the inclusion criteria. Overall, 47 (32%) patients underwent orthopaedic intervention. Operative management was associated with increased length (3.17 vs. 1.40 d) and cost ($27,850 vs. $10,716) of admission. The clinical resolution was documented in 57/58 patients (98%) in the nonoperative group and 41/42 patients (98%) in the operative group. The median duration to resolution was 21 days for both groups.

CONCLUSIONS

Operative management of pediatric patients with Lyme arthritis is associated with increased resource utilization and costs while being similarly efficacious to nonoperative management. As the US Lyme epidemic expands, improved diagnosis and management of acute undifferentiated arthritis may prevent unneeded operative intervention.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Cytochrome b Drug Resistance Mutation Decreases Babesia Fitness in the Tick Stages But Not the Mammalian Erythrocytic Cycle

Human babesiosis is an emerging tick-borne malaria-like illness caused by Babesia parasites following their development in erythrocytes. Here, we show that a mutation in the Babesia microti mitochondrial cytochrome b (Cytb) that confers resistance to the antibabesial drug ELQ-502 decreases parasite fitness in the arthropod vector. Interestingly, whereas the mutant allele does not affect B. microti fitness during the mammalian blood phase of the parasite life cycle and is genetically stable as parasite burden increases, ELQ-502-resistant mutant parasites developing in the tick vector are genetically unstable with a high rate of the wild-type allele emerging during the nymphal stage. Furthermore, we show that B. microti parasites with this mutation are transmitted from the tick to the host, raising the possibility that the frequency of Cytb resistance mutations may be decreased by passage through the tick vector, but could persist in the environment if present when ticks feed.

Lyme Neuroborreliosis: Mechanisms of B. burgdorferi Infection of the Nervous System

Lyme borreliosis is the most prevalent tick-borne disease in the United States, infecting ~476,000 people annually. Borrelia spp. spirochetal bacteria are the causative agents of Lyme disease in humans and are transmitted by Ixodes spp ticks. Clinical manifestations vary depending on which Borrelia genospecies infects the patient and may be a consequence of distinct organotropism between species. In the US, B. burgdorferi sensu stricto is the most commonly reported genospecies and infection can manifest as mild to severe symptoms. Different genotypes of B. burgdorferi sensu stricto may be responsible for causing varying degrees of clinical manifestations. While the majority of Lyme borreliae-infected patients fully recover with antibiotic treatment, approximately 15% of infected individuals experience long-term neurological and psychological symptoms that are unresponsive to antibiotics. Currently, long-term antibiotic treatment remains the only FDA-approved option for those suffering from these chronic effects. Here, we discuss the current knowledge pertaining to B. burgdorferi sensu stricto infection in the central nervous system (CNS), termed Lyme neuroborreliosis (LNB), within North America and specifically the United States. We explore the molecular mechanisms of spirochete entry into the brain and the role B. burgdorferi sensu stricto genotypes play in CNS infectivity. Understanding infectivity can provide therapeutic targets for LNB treatment and offer public health understanding of the B. burgdorferi sensu stricto genotypes that cause long-lasting symptoms.

Pediatric decision limits for serologic screening of Lyme disease

BACKGROUND

Laboratory diagnosis of Lyme disease (LD) relies on a two-tier protocol. We have observed disproportionate equivocal serologies in children requiring reflex western blot (WB) using manufacturer-provided ranges based on adult studies. We aimed to determine appropriate ranges for our pediatric population.

METHODS

We performed a one-year retrospective institutional review of all 2755 children with LD testing with the Vidas® Lyme IgM II/IgG II immunoassays with reflex to WB for equivocal/positive serologies. Results were assessed by frequency distributions, optimization via percent agreement analysis, and clinical adjudication.

RESULTS

The proposed ranges for IgM (negative ≤0.20, equivocal ≥0.21 to <0.32, positive ≥0.32) and IgG (negative ≤0.50, positive >0.50) allowed for a decrease in the IgM equivocal rate (7% to 2%) and IgG positive rate (15% to 13%). There was a decrease in the positive percent agreement between tiers (95% to 83% and 98% to 95%) with increase in the negative (32% to 63% and 70% to 81%) and overall (65% to 73% and 85% to 88%) percent agreements for IgM and IgG, respectively. Of 15 IgM serologies reclassified as negative with a positive WB and not positive for IgG, 8 were clinically negative, 5 were clinically positive, and two had insufficient history. Of the 10 IgG serologies reclassified as negative with a positive WB 3 were clinically positive, 6 were clinically negative and one had insufficient history.

CONCLUSIONS

Our modified ranges are more suitable for our pediatric population while reducing overdiagnosis, unnecessary treatment, diagnostic uncertainty, and turnaround time.

Ticks infesting dogs and cats in North America: Biology, geographic distribution, and pathogen transmission

A diverse array of ixodid and argasid ticks infest dogs and cats in North America, resulting in skin lesions, blood loss, and disease. The ticks most commonly found on pets in this region are hard ticks of the genera Amblyomma, Dermacentor, Ixodes, and Rhipicephalus, as well as the more recently established Haemaphysalis longicornis. Soft tick genera, especially Otobius and Ornithodoros, are also reported from pets in some regions. In this review, we provide a summary of the complex and diverse life histories, distinct morphologies, and questing and feeding behaviors of the more common ticks of dogs and cats in North America with a focus on recent changes in geographic distribution. We also review pathogens of dogs and cats associated with the different tick species, some of which can cause serious, potentially fatal disease, and describe the zoonotic risk posed by ticks of pets. Understanding the natural history of ticks and the maintenance cycles responsible for providing an ongoing source of tick-borne infections is critical to effectively combatting the challenges ticks pose to the health of pets and people.

The Many Faces of Emerging and Reemerging Infectious Disease

The emergence of disease threats can take many forms, from the adaptation of a traditionally zoonotic pathogen for efficient spread in humans, to the development of antibiotic resistance in well-known pathogens, to the creation of new niches for established disease through social and societal changes. In this commentary, the authors explore these various facets of disease emergence through the lens of the papers included in this issue of Epidemiologic Reviews. The authors explore multiple aspects of emergence and the ways in which emergent pathogens can be controlled with the limited tools available. In doing so, they put the papers in this issue in the context of the broader research agenda around understanding and combatting emergent pathogens.

Surveillance for Borrelia spp. in Upland Game Birds in Pennsylvania, USA

The Borrelia genus contains two major clades, the Lyme borreliosis group, which includes the causative agents of Lyme disease/borreliosis (B. burgdorferi sensu stricto and other related B. burgdorferi sensu lato genospecies), and the relapsing fever borreliosis group (B. hermsii, B. turicatae, and B. parkeri). Other unclassified reptile- and echidna-associated Borrelia spp. (i.e., B. turcica and 'Candidatus Borrelia tachyglossi', respectively) do not belong in either of these two groups. In North America, Borrelia spp. from both of the major clades are important pathogens of veterinary and public health concern. Lyme disease is of particular interest because the incidence in the northeastern United States continues to increase in both dogs and humans. Birds have a potentially important role in the ecology of Borrelia species because they are hosts for numerous tick vectors and competent hosts for various Borrelia spp. Our goal was to investigate the prevalence of Borrelia spp. in four free-living species of upland game birds in Pennsylvania, USA including wild turkey (Meleagris gallopavo), ruffed grouse (Bonasa umbellus), ring-necked pheasants (Phasianus colchicus), and American woodcock (Scolopax minor). We tested 205 tissue samples (bone marrow and/or spleen samples) from 169 individuals for Borrelia using a flagellin gene (flab) nested PCR, which amplifies all Borrelia species. We detected Borrelia DNA in 12% (24/205) of samples, the highest prevalence was in wild turkeys (16%; 5/31), followed by ruffed grouse (13%; 16/126) and American woodcock (3%; 1/35). All pheasants (n = 13) were negative. We sequenced amplicons from all positive game birds and all were B. burgdorferi sensu stricto. Our results support previous work indicating that certain species of upland game birds are commonly infected with Borrelia species, but unlike previous studies, we did not find any relapsing fever borreliae.

Current and Future Spatiotemporal Patterns of Lyme Disease Reporting in the Northeastern United States

IMPORTANCE

The incidence and geographic range of Lyme disease continues to increase in the United States because of the expansion of Ixodes scapularis, the species of tick that is the main Lyme disease vector. Currently, no dynamic model for the disease spread exists that integrates information of both acarological and human case surveillance data.

OBJECTIVE

To characterize the spatiotemporal spread of Lyme disease in humans among counties in US endemic regions.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study modeled the spread of Lyme disease county-level case reporting, accounting for county-level demographic factors, environmental factors associated with tick presence and human exposure, and the spatiotemporal association between counties. The analyses were conducted between January and August 2019. The setting was 1405 counties in the following regions of the United States: West North Central, East North Central, New England, Middle Atlantic, and the South. Assessments were based on publicly available Lyme disease case data reported to the US Centers for Disease Control and Prevention (CDC) between January 2000 and December 2017.

MAIN OUTCOMES AND MEASURES

Probability of reporting the first case of Lyme disease by county by year.

RESULTS

Between 2000 and 2017, a total of 497 569 Lyme disease cases were reported to the CDC in the study area. Reporting a first case of Lyme disease was associated with a county's and county's neighbors' forest coverage, elevation, percentage of population living in the wildland-urban interface, tick presence, county's population size, proportion of neighbors reporting cases, and neighbors' years since first reporting. The model that included these variables showed high predictive power, with a mean area under the receiver operating characteristic curve of 81.1 (95% CI, 68.5-86.2). The model predicted the first reported Lyme disease case a mean (SD) of 5.5 (3.5) years earlier than was reported to the CDC, with a mean spread velocity estimated at 27.4 (95% CI, 13.6-54.4) km per year. Among 162 counties without reported cases, 47 (29.0%) had a high probability of reporting Lyme disease by 2018. The estimated mean time lag between the first reported case in a neighboring county and any county was 7 (95% CI, 3-8) years.

CONCLUSIONS AND RELEVANCE

This study's findings suggest that, if updated regularly and expanded geographically, this predictive model could enable states and counties to develop more specific Lyme disease prevention and control plans, including improved sensitization of the general population and medical community.

Increasing Burden of Lyme Carditis in United States Children's Hospitals

We sought to characterize the shifting epidemiology and resource utilization of Lyme disease and associated carditis in US children's hospitals. We hypothesized that the Lyme carditis burden has increased and that hospitalizations for Lyme carditis are costlier than those for Lyme disease without carditis. The PHIS database was queried for Lyme disease encounters between January 1, 2007 and December 31, 2013. Additional diagnostic codes consistent with carditis identified Lyme carditis cases. Demographic, clinical, and resource utilization data were analyzed. All costs were adjusted to 2014 US dollars. Lyme disease was identified in 3620 encounters with 189 (5%) associated with carditis. Lyme disease (360 cases in 2007 vs. 672 in 2013, p = 0.01) and Lyme carditis (17 cases in 2007 vs. 40 in 2013, p = 0.03) both significantly increased in frequency. This is primarily accounted for by their increase within the Midwest region. Carditis frequency among cases of Lyme disease was stable (p = 0.15). Encounters for Lyme carditis are dramatically costlier than those for Lyme disease without carditis [median $9104 (3741-19,003) vs. 922 (238-4987), p < 0.001] The increase in Lyme carditis cases in US children's hospitals is associated with an increased Lyme disease incidence, suggesting that there has not been a change in its virulence or cardiac tropism. The increasing number of serious cardiac events and costs associated with Lyme disease emphasize the need for prevention and early detection of disease and control of its spread.

Salp15, a Multifunctional Protein From Tick Saliva With Potential Pharmaceutical Effects

Ixodes ticks are the main vectors for a number of zoonotic diseases, including Lyme disease. Ticks secrete saliva directly into a mammalian host while feeding on the host's blood. This action serves to modulate host immunity and coagulation, thus allowing ticks to attach and feed upon their host. One of the most extensively studied components of tick saliva is Salp15. Research has shown that this protein binds specifically to CD4 molecules on the surface of T lymphocytes, interferes with TCR-mediated signaling transduction, inhibits CD4+ T cell activation and proliferation, and impedes the secretion of interleukin 2 (IL-2). Salp15 also binds specifically to dendritic cell dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) to up-regulate the expression of CD73 in regulatory T cells. Collectively, these findings render this salivary protein a potential candidate for a range of therapeutic applications. Here, we discuss our current understanding of Salp15 and the mechanisms that might be used to treat disease.

Lyme Disease Risk of Exposure to Blacklegged Ticks (Acari: Ixodidae) Infected with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) in Pittsburgh Regional Parks

Lyme disease is the most commonly reported vector-borne illness and sixth most commonly reported notifiable infectious disease in the United States. The majority of cases occur in the Northeast and upper-Midwest, and the number and geographic distribution of cases is steadily increasing. The blacklegged tick (Ixodes scapularis Say) is the principal vector of the Lyme disease spirochete (Borrelia burgdorferi sensu stricto) in eastern North America. Although Lyme disease risk has been studied in residential and recreational settings across rural to urban landscapes including metropolitan areas, risk within U.S. cities has not been adequately evaluated despite the presence of natural and undeveloped public parkland where visitors could be exposed to B. burgdorferi-infected I. scapularis. We studied the occurrence of I. scapularis and infection prevalence of B. burgdorferi in four insular regional parks within the city of Pittsburgh to assess Lyme disease risk of exposure to infected adults and nymphs. We found that the density of I. scapularis adults (1.16 ± 0.21 ticks/100 m2) and nymphs (3.42 ± 0.45 ticks/100 m2), infection prevalence of B. burgdorferi in adults (51.9%) and nymphs (19.3%), and density of infected adults (0.60 ticks/100 m2) and nymphs (0.66 ticks/100 m2) are as high in these city parks as nonurban residential and recreational areas in the highly endemic coastal Northeast. These findings emphasize the need to reconsider, assess, and manage Lyme disease risk in greenspaces within cities, especially in high Lyme disease incidence states.

Trends in canine seroprevalence to Borrelia burgdorferi and Anaplasma spp. in the eastern USA, 2010-2017

Background

Borrelia burgdorferi and Anaplasma phagocytophilum are tick-borne infections transmitted by Ixodes scapularis in the eastern USA; both agents cause disease in dogs and people. To characterize changes in seroprevalence over time, Cochran Armitage trend tests were used to evaluate percent positive test results for antibodies to B. burgdorferi and Anaplasma spp. in approximately 20 million canine tests from 2010–2017 in 25 states and 905 counties in the eastern USA.

Results

A significant decreasing trend in seroprevalence to B. burgdorferi was evident in eight states along the mid-Atlantic coast from Virginia to New Hampshire, and in Wisconsin. In contrast, a continued increasing trend was evident in five northeastern and Midwestern states where Lyme borreliosis is endemic or emerging, as well as in three southern states where endemicity has not yet been widely established. Similarly, seroprevalence to Anaplasma spp. showed a significant, although smaller, decreasing trend in five states along the mid-Atlantic coast from Virginia to Connecticut and Rhode Island, as well as in Minnesota and Wisconsin in the Midwest; despite the fact that those trends were significant they were weak. However, a strong increasing trend was evident in Massachusetts and three states in northern New England as well as in Pennsylvania.

Conclusions

As expected, seroprevalence continued to increase in regions where Lyme borreliosis and anaplasmosis are more newly endemic. However, the declining seroprevalence evident in other areas was not anticipated. Although the reasons for the decreasing trends are not clear, our finding may reflect shifting ecologic factors that have resulted in decreased infection risk or the combined positive influence of canine vaccination, tick control, and routine testing of dogs in regions where these infections have long been endemic. Analysis of trends in canine test results for tick-borne infections continues to be a valuable tool to understand relative geographical and temporal risk for these zoonotic agents.

A 4-Yr Survey of the Range of Ticks and Tick-Borne Pathogens in the Lehigh Valley Region of Eastern Pennsylvania

Questing ticks were surveyed by dragging in forested habitats within the Lehigh Valley region of eastern Pennsylvania for four consecutive summers (2015-2018). A high level of inter-annual variation was found in the density of blacklegged tick nymphs, Ixodes scapularis Say, with a high density of host-seeking nymphs (DON) in summer 2015 and 2017 and a relatively low DON in summer 2016 and 2018. Very few American dog ticks (Dermacentor variabilis Say) and Ixodes cookei Packard were collected. Lone star ticks (Amblyomma americanum L.) and longhorned ticks (Haemaphysalis longicornis Neumann) were not represented among the 6,398 ticks collected. For tick-borne pathogen surveillance, DNA samples from 1,721 I. scapularis nymphs were prepared from specimens collected in summers 2015-2017 and screened using qPCR, high resolution melting analysis, and DNA sequencing when necessary. The overall 3-yr nymphal infection prevalence of Borrelia burgdorferi was 24.8%, Borrelia miyamotoi was 0.3%, Anaplasma phagocytophilum variant-ha was 0.8%, and Babesia microti was 2.8%. Prevalence of coinfection with B. burgdorferi and B. microti as well as B. burgdorferi and A. phagocytophilum variant-ha were significantly higher than would be expected by independent infection. B. burgdorferi nymphal infection prevalence is similar to what other studies have found in the Hudson Valley region of New York, but levels of B. microti and A. phagocytophilum variant-ha nymphal infection prevalence are relatively lower. This study reinforces the urgent need for continued tick and pathogen surveillance in the Lehigh Valley region.