Importance:Babesiosis is a worldwide emerging tick-borne disease with an expanding geographic range in the US, Europe, and Asia. Red blood cell exchange transfusion (ET) is often used as an adjunctive treatment for severe illness from babesiosis, particularly in patients with high parasitemia, acute organ injury, or severe hemolytic anemia. Data supporting its clinical effectiveness, however, are lacking. Objective:To test whether ET improves clinical outcomes among hospitalized adult patients with severe babesiosis. Design, Settings, and Participants:This target trial emulation used data from a multicenter cohort study of 3233 consecutive adults hospitalized with babesiosis from 2010 to 2024 at 82 sites across the northeastern US. Patients were eligible if they had parasitemia greater than 10%, or 5% to 10% with either acute organ injury or severe hemolytic anemia. Data were analyzed from April to August 2025. Exposure:Treatment with ET in the first 7 days of hospitalization. Main Outcomes and Measures:A composite of in-hospital death or 30-day readmission. Outcomes were compared between patients who received ET within the first 7 days of admission and those who did not. The analysis used logistic regression, with inverse probability of treatment weighting (IPTW) to adjust for potential confounders. Results:The analysis included 629 patients (median [IQR] age, 71 [63-79] years; 446 male [70.9%]), among whom 209 (33.2%) received ET in the first 7 days of hospitalization. Patients treated with ET were more severely ill at baseline than those not treated with ET (median parasitemia, 14.0% vs 7.2%); however, severity of illness characteristics were well balanced after applying IPTW. In the main analysis, the primary end point occurred in 3.6% of patients who received ET and in 9.8% who did not (adjusted odds ratio, 0.22; 95% CI, 0.09-0.51). The benefit of ET was confirmed in multiple sensitivity analyses. Conclusions and Relevance:This multicenter cohort study found that among severely ill adults hospitalized with babesiosis, the adjusted risk of in-hospital death or 30-day readmission was nearly 5-fold lower in those treated with ET vs those not treated with ET. These data support ET for severely ill patients with babesiosis, although the findings may be susceptible to unmeasured confounding. Further research is needed to identify which patients are most likely to benefit.

Background:Electronic health records provide opportunities for improving Lyme disease surveillance by collecting detailed clinical information and timely, scalable disease incidence estimation. Medical record review can improve understanding of clinical manifestations, how likely and possible cases compare, and potential misclassification of possible cases. Methods:The SubLyme Network is a collaboration among 5 healthcare systems, a coordinating center, and the Centers for Disease Control and Prevention. The sites each conducted stratified random sampling of 500 potential acute Lyme disease episodes for medical record review from patients with a diagnosis, test order, and/or appropriate antibiotic in 2022 or 2023. Reviewers abstracted data, including from free text notes, to classify patients as likely or possible Lyme disease and by clinical manifestation. Multivariable logistic regression was used to identify differences between possible compared to likely Lyme disease cases. Results:Among 2500 reviews, 880 patients were categorized as having likely or possible new onset, active Lyme disease. The patient proportion identified as having a specific clinical manifestation ranged from 61% to 76% across sites. Of likely and possible cases, 55.9%, 7.8%, 1.3%, and 3.1% were diagnosed with erythema migrans, Lyme arthritis, Lyme carditis, and neuroborreliosis, respectively. Possible cases differed from likely cases in having more nonspecific symptoms, non-Lyme disease diagnoses, provider uncertainty, and undocumented provider decision-making. Conclusions:Medical record review is expected to be more accurate than computable phenotypes for Lyme disease identification and staging, yet likely and possible cases were challenging to distinguish, and a sizable proportion could not have clinical manifestation assigned. Findings provide direction for computable phenotype refinement to improve case identification. KEY WORDS: clinical manifestations, electronic health records, epidemiology, Lyme disease, surveillance.

Background Lyme disease is the most common vector-borne illness in the United States. The limitations of traditional surveillance strategies for Lyme disease affect the ability to reliably track its burden and evaluate interventions. The US Centers for Disease Control and Prevention (CDC) established the Surveillance Based Lyme Disease Network (SubLyme) in September 2023 to strengthen Lyme disease surveillance and research using electronic health record (EHR) data. Objective SubLyme has three primary objectives: (1) to establish and evaluate criteria for identifying Lyme disease cases in EHR data (ie, create computable phenotypes [CPs]) that can be scaled across diverse health systems, (2) to estimate Lyme disease incidence, and (3) to describe Lyme disease incidence by key demographics. Secondary objectives are to develop CPs that distinguish between acute and disseminated Lyme disease, identify clinical manifestations, and support future research efforts. This paper describes SubLyme, its structure, and its methods. Methods SubLyme includes 5 health systems in 3 US regions with a high risk of Lyme disease: Geisinger, in Pennsylvania; Marshfield Clinic Health System, in Wisconsin; and Mass General Brigham, Tufts Medical Center, and MaineHealth in New England. The network is administered by a coordinating center (Westat) and the US CDC. SubLyme is evaluating the validity of EHR-based CP definitions for Lyme disease. CP performance is assessed by measuring sensitivity, specificity, positive predictive value, and negative predictive value against manually abstracted medical charts. Each site identified a cohort of patients with any Lyme disease element in their EHR (Lyme disease diagnosis code, Lyme disease laboratory test order, and Lyme-appropriate antibiotic order) during 2022 to 2023 and selected 500 charts for manual review as the gold standard against which CP performance was evaluated. SubLyme will use the Lyme disease CPs to generate incidence rates for Lyme disease overall and for various subgroups. Results SubLyme identified 332,256 patients with at least 1 Lyme disease element in their record from more than 4.6 million patients. Of these patients, 55.6% (n=184,734) were female, 87.9% (n=292,053) were White, and 90.8% (n=301,688) were non-Hispanic. More than half of the patients only had a Lyme-appropriate medication order (n=177,425, 53.4%) and 35.8% (n=118,948) only had a Lyme disease test order. The most common combination was a medication order with a laboratory test order (n=22,926, 6.9%), followed by a combination of a diagnosis, test, and medication order (n=5316, 1.6%). Conclusions SubLyme is well positioned to advance Lyme disease surveillance using EHR data across multiple health systems. The exploration of new surveillance methods in Lyme disease is critical as disease frequency increases and the geography expands. An EHR-based approach to surveillance has the potential to overcome challenges of current surveillance strategies and to accelerate Lyme disease research. International Registered Report Identifier (IRRID) DERR1-10.2196/94921

INTRODUCTION:Human babesiosis is an emerging tick-borne disease caused by intraerythrocytic Babesia protozoa. Most cases are due to Babesia microti, which is endemic in the northeastern and upper Midwestern United States. Other Babesia spp. cases are endemic in China and/or sporadically reported in the United States, Europe, Asia, and elsewhere in the Northern Hemisphere. Cases in immunocompetent hosts are typically mild to moderate, while disease in immunocompromised hosts is often severe. AREAS COVERED:A historical perspective of compounds that are effective against Babesia spp. is provided. The current management of mild, moderate, and severe babesiosis is discussed, as is the genetic basis of antimicrobial resistance associated with relapsing babesiosis. The use of red blood cell exchange transfusion is reviewed. EXPERT OPINION/COMMENTARY:Most cases of human babesiosis are successfully treated with atovaquone plus azithromycin or clindamycin plus quinine. A major research topic is the management of immunocompromised hosts, especially those experiencing severe or relapsing babesiosis. Two immediate goals are, (i) to develop new antimicrobial agents that target Babesia spp. through novel mechanisms and can overcome resistance to currently recommended antimicrobial agents and, (ii) to gain a better understanding of the efficacy of red blood cell exchange transfusion and indications for its use.

Enterococci are opportunistic pathogens displaying a characteristic ovoid shape, typically forming pairs of cells (diplococci) and short chains. Control of cell chain length in Enterococcus faecalis relies on the activity of the major N-acetylglucosaminidase AtlA. The formation of short chains and diplococci is critical during pathogenesis for dissemination in the host and to limit recognition by innate immune effectors such as complement molecules and phagocytes. Here, we identify AtlE, an N-acetylmuramidase that contributes to septum cleavage during stationary phase in the absence of AtlA. AtlE is encoded by the locus required to produce the decoration subunits of the Enterococcal Polysaccharide Antigen (EPA), which mediate evasion of phagocytosis. We show that peptidoglycan hydrolysis by AtlE is essential for pathogenesis and demonstrate that soluble cell wall fragments containing EPA decorations increase the virulence of E. faecalis, suggesting that EPA plays a role as a decoy molecule to evade host defences. This research sheds light on the complex interplay between bacterial cell division, cell wall remodelling, and the host immune system, providing valuable insights into a novel mechanism underlying the virulence of E. faecalis.

Abstract Targeting host proteins that are crucial for viral replication offers a promising antiviral strategy. We have designed and characterised antiviral PROteolysis TArgeting Chimeras (PROTACs) targeting the human protein cyclophilin A (CypA), a host cofactor for unrelated viruses including human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The PROTAC warheads are based on fully synthetic macrocycles derived from sanglifehrin A, which are structurally different from the classical Cyp inhibitor, cyclosporine A. Our Cyp-PROTACs decrease CypA levels in cell lines and primary human cells and have high specificity for CypA confirmed by proteomics experiments. Critically, CypA degradation facilitates improved antiviral activity against HIV-1 in primary human CD4+ T cells compared to the non-PROTAC parental inhibitor, at limiting inhibitor concentrations. Similarly, we observe antiviral activity against HCV replicon in a hepatoma cell line. We propose that CypA-targeting PROTACs inhibit viral replication potently and anticipate reduced evolution of viral resistance and broad efficacy against unrelated viruses. Furthermore, they provide powerful tools for probing cyclophilin biology.

BackgroundThe incidence of tick-borne diseases is increasing across the USA, with cases concentrated in the northeastern and midwestern regions of the country. Ixodes scapularis is one of the most important tick-borne disease vectors and has spread throughout the northeastern USA over the past four decades, with established populations in all states of the region.MethodsTo better understand the rapid expansion of I. scapularis and the pathogens they transmit, we aggregated and analyzed I. scapularis abundance and pathogen prevalence data from across the northeastern USA, including the states of Connecticut, Maine, New Hampshire, New York and Vermont, from 1989 to 2021. Maine was the only state to collect data during the entire time period, with the other states collecting data during a subset of this time period starting in 2008 or later. We harmonized I. scapularis abundance by county and tick season, where the nymph season is defined as May to September and the adult season is October to December, and calculated I. scapularis pathogen infection prevalence as the percentage of ticks that tested positive for Anaplasma phagocytophilum, Babesia microti, Borrelia burgdorferi, and Borrelia miyamotoi. We then explored temporal trends in I. scapularis abundance and pathogen prevalence data using linear models.ResultsThe resulting dataset is one of the most spatially and temporally comprehensive records of tick abundance and pathogen prevalence in the USA. Using linear models, we found small or insignificant changes in the abundance of nymphs and adults over time; however, A. phagocytophilum, B. microti and B. burgdorferi prevalence in both nymphs and adults has increased over time. For the period 2017-2021, the statewide average prevalence of B. burgdorferi ranged from 19% to 25% in I. scapularis nymphs and from to 49% to 54% in I. scapularis adults. The statewide average prevalence of all other pathogens in I. scapularis for 2017-2021, including A. phagocytophilum (4-6% for nymphs, 4-9% for adults), B. microti (4-8% for nymphs, 2-13% for adults) and B. miyamotoi (1-2% for nymphs, 1-2% for adults), was considerably less.ConclusionsOur efforts revealed the complications of creating a comprehensive dataset of tick abundance and pathogen prevalence across time and space due to variations in tick collection and pathogen testing methods. Although tick abundance has not changed along the more southern latitudes in our study over this time period, and only gradually changed in the more northern latitudes of our study, human risk for exposure to tick-borne pathogens has increased due to increased pathogen prevalence in I. scapularis. This dataset can be used in future studies of I. scapularis and pathogen prevalence across the northeastern USA and to evaluate models of I. scapularis ecology and population dynamics.

Lyme disease, caused by Borrelia burgdorferi, is the most common vector-borne disease in the United States, and the range of its tick vector continues to expand. Most Lyme disease cases are diagnosed with the onset of the erythema migrans rashes, which can be single or multiple and vary from a homogeneous erythema to bull's-eye patterns. Serologic antibody testing is of low sensitivity at onset but becomes highly sensitive after a few weeks. Early dissemination may lead to neurologic and cardiac complications. Mono- or oligoarticular arthritis may develop in untreated patients. Antibiotic treatment is highly effective, but approximately 10% of treated patients experience persistent symptoms.

In a nature reserve in southern Maine, we removed invasive Japanese barberry (Berberis thunbergii de Candolle) along sections of forested recreational trails that ran through dense barberry infestations. Barberry thickets provide questing substrate and a protective microclimate for blacklegged ticks (Ixodes scapularis Say), and trail users could brush up against encroaching barberry and acquire ticks. Trailside barberry removal will reduce or eliminate encroaching tick questing substrate and could reduce trailside questing tick abundance by creating a microclimate more hostile to ticks. The same-day cut-and-spray treatment comprised mechanical cutting of barberry clumps (individual plants with numerous ramets) followed immediately by targeted herbicide application to the resulting root crowns. The treatment created trail shoulders to a lateral width of 1-2 m on both sides of 100-m trail sections, with initial treatment in the fall of 2013 and one retreatment in the summer of 2014. Our aim was to remove 90% of barberry clumps to achieve a 50% or better reduction in questing tick abundance on trail shoulders. However, by the fall of 2015, there were only 41% fewer barberry clumps on treated vs. untreated trail sections and there was no reduction in either adults or nymphs. We concluded that our barberry treatment protocol was not sufficiently aggressive since the resulting ecotone habitat on trail shoulders proved suitable for questing I. scapularis. In principle, cutting back barberry along trails should reduce trail user contact with questing deer ticks, but we were unable to demonstrate a reduction in trailside tick abundance.

The purpose of this conceptual article is to document major threats to online survey data quality through the lens of current practices in the marketing research industry. The Fair Framework categorizes threats ranging from respondent misbehavior to criminal activity in the form of survey fraud. Real examples provide evidence of threats by individual humans as well as serious weaknesses undermining the research supply chain infrastructure, especially regarding sampling. This paper offers academic and practitioner researchers detailed knowledge and actionable insights to effectively combat data quality threats and support the development of robust, reliable, and ethical marketing research practices.

L-Rhamnose-containing polysaccharides are produced by Streptococci and Enterococci. They define Lancefield serotypes and represent promising candidates for the design of glycoconjugate vaccines. The Enterococcal Polysaccharide Antigen produced by the opportunistic pathogen Enterococcus faecalis plays a critical role in normal growth, division, biofilm formation, antimicrobial resistance, phage susceptibility, and innate immune evasion. Despite the critical role of this polymer for E. faecalis physiology and host-pathogen interactions, little information is available on its structure and biosynthesis. Here, we elucidate the structure of the intact EPA produced by E. faecalis OG1RF. We report the structure of the linkage unit, revealing an unprecedented complexity of the rhamnose backbone and decorations. Finally, we explore the impact of several EPA structural modifications on innate immune evasion and recognition by bacteriophages. This work represents a first step towards the functional characterisation of EPA for the rational design of therapeutic strategies against a group of important pathogens. ### Competing Interest Statement The authors have declared no competing interest.

Powassan virus lineage II or deer tick virus (DTV) is a rare but increasingly reported human infection in the United States transmitted by Ixodes scapularis ticks. The virus is thought to be maintained in environmental foci that are optimal for tick and vertebrate reservoirs, but details on DTV ecology are poorly understood. We investigated DTV tick infection rates and reservoir host abundance in a focus of consistent DTV activity in Maine, USA. Host and tick abundance, vegetation, and microclimate conditions were measured in three forest sites representing increasing invasive understory infestation. Sites were selected representing native understory, mixed vegetation with some invasive Japanese barberry ( Berberis thunbergii ), and a highly invasive site dominated by Japanese barberry. Japanese barberry in the mixed vegetation site averaged 1 m in height with space between plants, whereas the highly invasive site had impenetrable Japanese barberry over 1.5 m. The DTV infection rate was greater in the highly invasive site. Density of I. scapularis ticks were significantly lower in the native forest site, and no DTV was found. Another feature of the DTV focus was more stable humid microclimate throughout the year compared with the other sites and a nearby continuous section of forest, consistent with reports from Connecticut, USA. We conclude that invasive Japanese barberry stands provide favorable and consistent microclimate conditions to maintain high DTV infection rates annually among questing I. scapularis ticks. Understanding environmental and landscape features that support high infection rates could lead to the identification of high-risk habitats for contracting DTV.

Streptococci, Lactococci and Enterococci all produce L-rhamnose-containing cell wall polysaccharides which define Lancefield serotypes and represent promising candidates for the design of glycoconjugate vaccines. The L-rhamnose containing Enterococcal Polysaccharide Antigen (EPA), produced by the opportunistic pathogen Enterococcus faecalis, plays a critical role in normal growth, division, biofilm formation, antimicrobial resistance, phage susceptibility, and innate immune evasion. Despite the critical role of this polymer in E. faecalis physiology and host-pathogen interactions, little information is available on its structure and biosynthesis. Here, using an NMR approach, we elucidate the structure of EPA and propose a model for biosynthesis. We report the structure of the EPA-peptidoglycan linkage unit and reveal an unprecedented complexity of the EPA rhamnose backbone and decoration subunits. Finally, we explore the impact of several EPA structural modifications on innate immune evasion and recognition by bacteriophages. This work represents a first step towards the functional characterisation of EPA and the rational design of therapeutic strategies against a group of important pathogens.

Deer tick virus (DTV), also known as Powassan virus lineage II, is a rising health concern due to increased recognition as a cause of human encephalitis. Since European tick-borne encephalitis virus persists in nature in enzootic foci (i.e., higher prevalence rates in small pockets in nature), we sought to determine whether DTV is also focally maintained in relation to habitat type, to better understand factors leading to human risk of exposure. From 2018 to 2021, questing Ixodes scapularis ticks were collected from five habitats at the Wells National Estuarine Research Reserve (WNERR) in Wells, ME: forest with invasive vegetation in the understory, edge, shrub, forest with native vegetation in the understory, and open field. Deer tick virus prevalence was greater in adult ticks (2.0%) than in nymphs (0.5%). Deer tick virus prevalence in adult ticks collected from forest with invasive vegetation was 3.2% compared to 0 to 1.7% in other habitat types. A hot spot analysis revealed a higher number of infected adults collected per hour on one of the transects located in forest with invasive vegetation. Phylogenetic analysis of 37 full-length DTV genomes sequenced in this study revealed four major clades from the WNERR, and there was high genetic diversity within each transect, suggesting frequent, short-range dispersal between habitats. Analysis of DTV sequences from other New England counties and states also indicated long-distance dispersal to and/or from the WNERR. This study provides preliminary evidence that DTV is focal and that the risk of encountering DTV-infected ticks in forest with invasive vegetation may be greater than in other habitat types.