Mitigation Protocols Research Articles

Rituximab Safety Profile: A Seven-Year Retrospective Analysis From Southern India.

This study aimed to analyze the pattern, severity, and outcomes of adverse drug reactions (ADRs) associated with rituximab use reported to a regional pharmacovigilance center in Kerala, India. This retrospective study analyzed rituximab-associated ADRs reported from 2017 to 2023. ADRs were assessed using the WHO-UMC criteria for causality and the Modified Hartwig Siegel Scale for severity. A total of 74 patients reported ADRs, with 49 being female. The majority (27 patients) were in the 51- to 60-year age group. Malignancies accounted for 58 cases of rituximab use. Most ADRs (69 cases) occurred with the first dose, with infusion reactions being the most common. Causality assessment revealed that 48 ADRs were probably related to rituximab. Severity analysis using the Modified Hartwig Siegel Scale showed that 67 ADRs were level two (mild), while two were level seven (severe). The majority of patients (72) recovered. However, rituximab-induced lung disease, observed in two cases, was associated with higher mortality. Rituximab demonstrated an acceptable safety profile, with most ADRs being non-serious and manageable. The high recovery rate reflects effective ADR management. However, the potential for serious complications, particularly rituximab-induced lung disease, highlights the need for vigilant monitoring, especially during the first infusions. These findings enhance understanding of rituximab's real-world safety profile and underscore the importance of standardized protocols for ADR mitigation.

Comprehensive Analysis of Purpura Fulminans as an Uncommon Postoperative Complication: A Case Series.

Acute infectious purpura fulminans (AIPF) is a rare but potentially fatal postoperative complication characterised by rapidly progressing disseminated intravascular coagulation (DIC), widespread purpura, and multi-organ dysfunction. Despite its severe and critical outcomes, the literature on this condition in the postoperative context is limited. This study aimed to analyse and evaluate the incidence, clinical presentation, laboratory findings, management strategies, and outcomes of postoperative AIPF in patients who underwent various surgical procedures. A retrospective case series was conducted, identifying adult patients diagnosed with AIPF within 30 days post surgery from January 2017 to December 2022. Inclusion was based on the International Classification of Diseases, Tenth Revision (ICD-10) coding for purpura fulminans and DIC. Clinical data, including demographic details, type and duration of surgery, onset of symptoms, laboratory findings, microbiology results, treatment strategies, and outcomes, were collected from electronic medical records. Data analysis included descriptive statisticsand differences in survival among surgical subgroups were assessed using Kaplan-Meier survival analysis and the log-rank test. Seven cases of AIPF were identified, with a mean patient age of 57.1 ± 12.5 years, out of which 71.4% (n = 5) were male. Surgical procedures included vascular (42.9%, n = 3), abdominal (28.6%, n = 2), thoracic (14.3%, n = 1), and orthopaedic (14.3%, n = 1) surgeries. The average surgical duration was 5.2 ± 2.7 hours and the mean onset of AIPF was 3.9 ± 1.9 days postoperatively. Clinically, all patients presented with widespread purpura, fever, hypotension, and multi-organ dysfunction, including renal, hepatic, and respiratory failure. Laboratory findings revealed severe coagulopathy, with a low platelet count, higher levels of D-dimer, prolonged prothrombin time, and activated partial thromboplastin time. Gram-negative bacteria were the most prevalent pathogens, particularly Klebsiella pneumoniae and Escherichia coli (28.6% each), while gram-positive Staphylococcus aureus was isolated in one case (14.3%). Despite comprehensive ICU management, including mechanical ventilation, fluid resuscitation, broad-spectrum antibiotics, and administration of fresh frozen plasma/cryoprecipitate (71.4%, n = 5), the mortality rate was 57.1% (n = 4). The median time to death was 48 hours (IQR = 36-72). The highest mortality was observed in vascular (33.3% survival) and thoracic (0% survival) surgery subgroups. Orthopaedic surgery demonstrated a 100% survival rate. AIPF after surgery is associated with significant morbidity and mortality, particularly following vascular and thoracic procedures. The findings underscore the need for heightened postoperative vigilance, early detection, and aggressive management to improve patient outcomes. Future studies should focus on identifying strategies for risk mitigation and early intervention protocols.

Consumer Safety and Pesticide Residues: Evaluating Mitigation Protocols for Greengrocery.

The application of pesticides remains a necessary measure for pest management in agriculture, particularly in the cultivation of fruits and vegetables. After harvest, the presence of pesticide residues in greengrocery (fruits and vegetables) is significantly influenced by various factors, including storage conditions, handling practices, and subsequent processing methods. The mitigation of these residues to levels compliant with regulated maximum thresholds ensures the safety of raw and processed fruits and vegetables for consumption. A contemporary survey of pesticide residues in greengrocery has gathered considerable attention from consumers, driven by concerns over the potential health risk of pesticide exposure. Consequently, consumers want to be extensively informed about household processing techniques to minimize associated risks. Meanwhile, a critical question arises: does household processing effectively eliminate pesticide residues? A comprehensive review of the literature reveals that conventional methods, such as washing and soaking, offer only limited reduction in residue levels, while emerging treatments, suitable both at household and industrial scale, demonstrate increased efficiency in residues mitigation. This study aims to emphasise the ubiquitous use of pesticides in crop cultivation while providing recommendations for the implementation of efficient treatment protocols to address residue concerns. Following upon available evidence and database mining, the worldwide purpose must be to outline agriculturally and economically viable strategies that prioritize both the health and safety of consumers, as well as the green cultivation and processing of fruits and vegetables.

Readout error mitigated quantum state tomography tested on superconducting qubits

Quantum technologies rely heavily on accurate control and reliable readout of quantum systems. Current experiments are limited by numerous sources of noise that can only be partially captured by simple analytical models and additional characterization of the noise sources is required. We test the ability of readout error mitigation to correct noise found in systems composed of quantum two-level objects (qubits). To probe the limit of such methods, we designed a beyond-classical readout error mitigation protocol based on quantum state tomography (QST), which estimates the density matrix of a quantum system, and quantum detector tomography (QDT), which characterizes the measurement procedure. By treating readout error mitigation in the context of state tomography the method becomes largely readout mode-, architecture-, noise source-, and quantum state-independent. We implement this method on a superconducting qubit and evaluate the increase in reconstruction fidelity for QST. We characterize the performance of the method by varying important noise sources, such as suboptimal readout signal amplification, insufficient resonator photon population, off-resonant qubit drive, and effectively shortened T1 and T2 coherence. As a result, we identified noise sources for which readout error mitigation worked well, and observed decreases in readout infidelity by a factor of up to 30.

Quantum error cancellation in photonic systems: Undoing photon losses

Real photonic devices are subject to photon losses that can decohere quantum information encoded in the system. In the absence of full fault tolerance, quantum error mitigation techniques have been introduced to help manage errors in noisy quantum devices. In this paper, we introduce an error mitigation protocol inspired by probabilistic error cancellation (a popular error mitigation technique in discrete variable systems) for continuous variable systems. We show that our quantum error cancellation protocol can undo photon losses in expectation value estimation tasks. To do this, we analytically derive the (nonphysical) inverse photon loss channel and decompose it into a sum over physically realizable channels with potentially negative coefficients. The bias of our ideal expectation value estimator can be made arbitrarily small at the cost of increasing the sampling overhead. The protocol requires a noiseless amplification followed by a series of photon subtractions. While these operations can be implemented probabilistically, for certain classes of initial state one can avoid the burden of carrying out the amplification and photon subtractions by leveraging Monte Carlo methods to give an unbiased estimate of the ideal expectation value. We validate our proposed mitigation protocol by simulating the scheme on squeezed vacuum states, cat states, and entangled coherent states. Published by the American Physical Society 2024

Tensor network noise characterization for near-term quantum computers

Characterization of noise in current near-term quantum devices is of paramount importance to fully use their computational power. However, direct quantum process tomography becomes unfeasible for systems composed of tens of qubits. A promising alternative method based on tensor networks was recently proposed []. In this paper, we adapt it for the characterization of noise channels on near-term quantum computers and investigate its performance thoroughly. In particular, we show how experimentally feasible tomographic samples are sufficient to accurately characterize realistic correlated noise models affecting individual layers of quantum circuits, and study its performance on systems composed of up to 20 qubits. Furthermore, we combine this noise characterization method with a recently proposed noise-aware tensor network error mitigation protocol for correcting outcomes in noisy circuits, resulting accurate estimations even on deep circuit instances. This positions the tensor-network-based noise characterization protocol as a valuable tool for practical error characterization and mitigation in the near-term quantum computing era. Published by the American Physical Society 2024

Study of noise in virtual distillation circuits for quantum error mitigation

Virtual distillation has been proposed as an error mitigation protocol for estimating the expectation values of observables in quantum algorithms. It proceeds by creating a cyclic permutation of M noisy copies of a quantum state using a sequence of controlled-swap gates. If the noise does not shift the dominant eigenvector of the density operator away from the ideal state, then the error in expectation-value estimation can be exponentially reduced with M. In practice, subsequent error mitigation techniques are required to suppress the effect of noise in the cyclic permutation circuit itself, leading to increased experimental complexity. Here, we perform a careful analysis of the effect of uncorrelated, identical noise in the cyclic permutation circuit and find that the estimation of expectation value of observables are robust against dephasing noise. We support the analytical result with numerical simulations and find that 67% of errors are reduced for M=2, with physical dephasing error probabilities as high as 10%. Our results imply that a broad class of quantum algorithms can be implemented with higher accuracy in the near-term with qubit platforms where non-dephasing errors are suppressed, such as superconducting bosonic qubits and Rydberg atoms.

Efficiently improving the performance of noisy quantum computers

Using near-term quantum computers to achieve a quantum advantage requires efficient strategies to improve the performance of the noisy quantum devices presently available. We develop and experimentally validate two efficient error mitigation protocols named ``Noiseless Output Extrapolation" and ``Pauli Error Cancellation" that can drastically enhance the performance of quantum circuits composed of noisy cycles of gates. By combining popular mitigation strategies such as probabilistic error cancellation and noise amplification with efficient noise reconstruction methods, our protocols can mitigate a wide range of noise processes that do not satisfy the assumptions underlying existing mitigation protocols, including non-local and gate-dependent processes. We test our protocols on a four-qubit superconducting processor at the Advanced Quantum Testbed. We observe significant improvements in the performance of both structured and random circuits, with up to 86% improvement in variation distance over the unmitigated outputs. Our experiments demonstrate the effectiveness of our protocols, as well as their practicality for current hardware platforms.

Parents' Perceptions of Schools' COVID-19 Mitigation Strategies: A Phenomenological Study.

At the onset of the COVID-19 pandemic, schools closed across the United States. Given the impact of virtual learning and lost access to school resources, schools eventually reopened with COVID-19 mitigation protocols in place. This qualitative study sought to understand parental perceptions of school-based COVID-19 mitigation strategies. Using a phenomenology approach, nine focus groups were completed with 40 parents of children in grades K-8 representing eight Maryland counties. Based on acceptance of masking policies (as indicated on a survey), parents were sorted into 2 groups-lower and higher masking acceptance. A thematic analysis was conducted for each group and themes were compared between the 2 groups. The main themes were related to parents' general sentiments regarding COVID-19, compliance, pandemic-related changes over time, changes in personal opinions, and in-person learning. Both groups described challenges related to inconsistent COVID-19 mitigation policies and practices, the challenges of rapid and frequent changes in guidelines during the pandemic, and the benefits of in-person learning. Parents of elementary and middle school children, regardless of general acceptance of masking policies, shared concerns about implementation and guidance regarding school-based mitigation strategies.

Ocular toxicities associated with antibody drug conjugates.

To review the structure, mechanism of action, and pathophysiology of antibody-drug conjugates (ADCs) used to treat gynecological malignancies associated with ocular adverse effects. Recent research shows tisotumab vedotin causes ocular toxicity localized to the conjunctiva, with common adverse effects being conjunctivitis, dry eye, blepharitis, and keratitis. Toxicity is likely due to targeting tissue factor (TF) in the conjunctiva, leading to direct delivery of the cytotoxic payload resulting in apoptosis and bystander killing. Mirvetuximab soravtansine causes blurred vision, keratitis, or dry eye with toxicity often localized in the cornea. Off-target inflammation appears to cause ocular adverse effects, with nonreceptor mediated macropinocytosis by corneal stem cells. Collaboration between oncologists and ophthalmologists with adherence to mitigation protocols can decrease the risk of ocular adverse events.

The empty code cart: Drug shortages over time.

In high-acuity situations such as cardiac arrest, clinicians rely on prepared medications stocked in code carts to provide timely and accurate pharmacotherapy. We examined shortage trends for medications commonly used in code carts. Drug shortage data from 2001 to 2022 were retrieved from the University of Utah Drug Information Service (UUDIS) to characterize shortages reported for commonly used code cart medications. Data extracted included the number of shortages, shortage duration, drug characteristics, and reason for the shortage. From 2001 to 2022, 71 drug shortages for code cart medications were reported. The number of new shortages peaked in 2010, and the number of total shortages peaked in 2010. At the end of the study period, 61 (84.7%) shortages had been resolved. For resolved shortages, the mean shortage duration was 18.2 months. The drug with the greatest number of reported shortages was dextrose (10 total), the drug with the longest resolved shortage was calcium chloride injection (116 months), and the drug with the longest active shortage was atropine injection (165 months at the end of the study period). Throughout the entire study period, only 2 suppliers provided commercially available prefilled syringes of dextrose for stocking on code carts. The most common reason for shortages, when reported, was manufacturing delays. Medications commonly used in code carts were frequently impacted by drug shortages, which have the potential to impact patient care. Institutional protocols for mitigation and larger efforts to promote a more resilient drug supply chain are critical to ensure patient safety and quality care.

Kinematics of 90° change of direction in young football players: Insights for ACL injury prevention from the CUTtheACLstudy on 6008 trials.

To investigate the 90° change of direction (COD) task in an extensive cohort of competitive healthy football players within the CUTtheACLstudy and to provide normative values and differences between males and females for full-body kinematics based on two-dimensional (2D) video analysis and scoring system. One-thousand-and-two competitive football (soccer) players (age 16.3 ± 2.8 years, 264 females) were prospectively enroled. Each player performed three preplanned 90° COD tasks per limb. The 2D evaluation was performed through objective measures (collected through three high-speed cameras) of frontal and sagittal plane joint kinematics at the cut initial foot contact (IC) and maximum knee flexion angle. A previously published scoring system was adopted to measure the movement quality of the COD task. The scoring system included five criteria (limb stability [LS], pelvis stability [PS], trunk stability [TS], shock absorption [SA], movement strategy [MS]) ranked from 0/2 (nonadequate) to 2/2 (adequate) with a maximum score of 10/10. Normative data were provided for all the variables; statistical differences between male and female players were investigated (p < 0.05). A total of 6008 valid attempts were included. Frontal plane knee projection angle (FPKPA) at initial contact was 24.4 ± 9.8° (95thpercentile: FPKPA > 40°). The total score was ≤4/10 in 71.2% of the trials, the lowest subscores were LS and PS. Female players showed different movement patterns with lower hip and trunk flexion both at IC and maximum knee flexion angle (p < 0.01, ES = 0.41-0.64). Female players also showed worse scores than males in SA, MSand total score (p < 0.01). Female players seem more prone to stiffer lower limb strategy and greater pelvis-trunk frontal plane instability than males. Clinicians could adopt normative data and sex-specific differences in players' movement techniques to improve ACL injury risk mitigation protocols. Level IV.

Thermal deflection in neutron scattering sample environments at Oak Ridge National Laboratory.

The neutron sources at Oak Ridge National Laboratory use a wide suite of sample environment equipment to deliver extreme conditions for a number of experiments. Much of this instrumentation focuses on extremes of temperature, such as cryostats, closed-cycle refrigerators in both low and high temperature configurations, and radiant heating furnaces. When the temperature is controlled across a large range, thermal deflection effects can notably move the sample and affect its alignment in the beam. Here, we combine these sample environments with neutron imaging and machine vision to determine the motion of a representative sample with respect to the neutron beam. We find vertical sample displacement on the order of 1-2mm and horizontal displacement that varies from near-negligible to 1.2mm. While these deflections are not relevant for some of the beamlines at the first target station at the spallation neutron source and the high flux isotope reactor, they will become critical for upcoming instrumentation at the second target station, as well as any instruments targeting sub-mm samples, as neutron sources and optics evolve to smaller and more focused beams. We discuss mitigation protocols and potential modifications to the environment to minimize the effect of misalignment due to thermal deflection.

Detection and mitigation of vehicle platooning disruption attacks

In response to the escalating challenges posed by traffic bottlenecks, accidents, and intersection delays, the deployment of platooning mechanisms emerges as an imperative remedy. This investigation revolves around a pivotal scenario wherein a closely-knit platoon of cooperative vehicles approaches an intersection. Orchestrated by a lead vehicle, this convoy navigates the traffic light to expedite the journey of its followers towards their respective destinations. However, given that the size of the platoon can be increased, it will become difficult for the leader to manage it smoothly. Therefore, dividing the platoon into small groups led by co-leaders who deal directly with the leader is considered an ideal solution to speed up and facilitate the process of maintaining platoon stability. In this paper, we propose a Cooperative Adaptive Platooning Control Algorithm (CAPCA) for the hybrid communication topology in platooning. In fact, CAPCA aims to achieve stability in the platoon by distributing tasks in a parallel manner to mini-platoons. Moreover, inherent complexities arise as select members within the platoon strive to undermine its stability. Within this context, the research addresses the intricacies of Vehicle Platooning Disruption (VPD) attacks, a menacing phenomenon characterized by deliberate efforts to destabilize or seize control of a platoon. These attacks manifest through tactics such as false data injection (FDI) and replaying of control messages. In response, a robust and multifaceted countermeasure is conceptualized. The Vehicle Platooning Disruption Attacks Detection Protocol (VPD-ADP) takes center stage as a foundational component. By identifying instability within the platoon's dynamics model, VPD-ADP lays the essential groundwork for mitigating the repercussions of FDI and replay attacks. Employing advanced stochastic time series analysis, the impact of VPD attacks is scrutinized via anomalies in the Cartesian coordinates of vehicles deviations from the trajectory anticipated by the platoon. Moreover, the study introduces the Reputation-based Reliable Mitigation Protocol (RRMP), a pioneering approach that leverages collaborative data gleaned from neighboring vehicles. RRMP is devised to assess the veracity of received messages and gauge their reliability in real-time. Through extensive simulations and experiments, the proposed approach's effectiveness in fortifying the resilience of vehicle platooning systems against an array of disruption attacks is convincingly demonstrated.

Optimizing emergency department imaging utilization for pulmonary emboli: A study on the effects of IV contrast rationing

PurposeTo study the impact of a contrast mitigation protocol on imaging utilization for pulmonary embolism (PE) in the emergency department (ED). Material and methodsMedical records of ED patients with suspected PE who underwent CT pulmonary angiography (CTPA) or ventilation-perfusion (VQ) scans were analyzed in control (3/15/22–4/15/22) and test (5/15/22–6/15/22) periods. The test period included a contrast mitigation protocol due to a global iodinated contrast shortage (05/2022–06/2022). Out of 610 scans, 28 were excluded for non-PE indications. Patient demographics, time metrics, and imaging reports were recorded. ResultsAmong 11,019 ED visits, there were 582 imaging events for suspected PE. The test period exhibited a significantly lower imaging rate of 4.16 % compared to 6.54 % in the control period (p < 0.001). CTPA usage decreased by 47.73 %, while VQ scan usage increased by 775.00 % during the test period. Test period positivity rate was 0.82 %, with CTPA at 0.58 % (1/173) and VQ scan at 1.43 % (1/70). In the control period, the positivity rate was 0.29 %, with CTPA at 0.30 % (1/331) and VQ scan at 0.00 % (0/8). Previous hospitalization history was significantly higher in the test period (70/243 vs. 39/339, p < 0.001). The positivity rates between the two periods showed no significant difference (p = 0.57). There were no significant differences in ED length of stay and image acquisition times. ConclusionThe contrast mitigation protocol reduced CTPA use, increased VQ scans, and maintained positivity rates and image acquisition times. However, concerns persist about unnecessary imaging and low positivity rates, necessitating further research to optimize PE diagnostic algorithms.

Applying the noiseless extrapolation error mitigation protocol to calculate real-time quantum field theory scattering phase shifts

Applying the noiseless extrapolation error mitigation protocol to calculate real-time quantum field theory scattering phase shifts

The Economics of DDoS Mitigation and Changing Internet Protocols

The Economics of DDoS Mitigation and Changing Internet Protocols

Radioprotective potential of whey protein against gamma irradiation-induced lingual damage.

Introduction: Ionizing radiation (IR) is effectively used in the treatment of oral malignancies; however, it might also significantly harm the surrounding tissues. Whey protein isolate (WP) is a protein derived from milk that exhibits a wide range of bioactivities. Therefore, the present research aimed to delineate the mitigating impact of WP against gamma irradiation-induced lingual damage. Methods: Rats were randomized into 5 groups: Control (saline, orally, 14days), WP (WP; 0.5g/kg b. w., orally, 14days), IR (saline, orally, 14days, exposed to 6 and 3Gy on days 4 and 6, respectively), WP+IR (WP was given orally for 14days before and after IR exposure; exposed to 6 and 3Gy on days 4 and 6, respectively), and IR+WP (WP, orally, started 24h after 1st IR exposure till the end of the experiment) groups. Samples were collected at two-time intervals (on the 7th and 14th days). Results and Discussion: Oxidative stress was stimulated upon IR exposure in tongue, indicated by boosted malondialdehyde (MDA) level, along with a decrease in the total antioxidant capacity (TAC) level, superoxide dismutase (SOD), and catalase (CAT) activities. Additionally, IR exposure depicted an increase of serum IgE, inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-6, along with overexpression mRNA levels of nuclear factor kappa-B transcription factor/p65 (NF-κB/p65), and down-regulation of nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase (HO-1) mRNA levels in tongue tissue. Moreover, IR triggered alterations in lingual histological architecture. The antioxidant and anti-inflammatory properties of WP mitigated oxidative damage, inflammation, and desquamation that were brought on following IR exposure. The protective administration of WP markedly decreases IR-induced lingual harm compared to the mitigation protocol. Our findings recommend WP supplements to the diets of cancer patients undergoing IR that might aid radioprotective effects.

Blockage‐free storage assignment and storage/retrieval scheduling in autonomous vehicle storage and retrieval systems

AbstractAutonomous vehicle storage and retrieval systems have greatly increased in popularity in the last decade. In such a system, at each tier multiple roaming vehicles transport totes between the storage locations and the lifts. However, this may lead to vehicle interference. We study in which order and by which vehicle the storage and retrieval requests should be executed to minimize the makespan, without vehicle interference. The optimal storage locations for incoming totes are also determined. A blocking mitigation protocol is proposed to address vehicle interference. We propose a two‐phase matheuristic, where in the first phase, the tier is divided into zones, with each zone assigned its own vehicle. The second phase focuses on reassigning requests between adjacent vehicles to obtain improved solutions. The models proposed in both phases are solved to optimality in polynomial time and pseudo‐polynomial time, respectively. Computational experiments show that the matheuristic produces high‐quality solutions within a few seconds, even for large‐sized instances, making it suitable for real‐time decisions. Compared to methods commonly used in practice, our matheuristic can reduce the makespan by up to 15%. Our results show that making integrated decisions that combine storage assignment and request scheduling, is more beneficial than sequential optimization in terms of throughput performance, space utilization and overall system cost. We also find that increasing the number of vehicles has a diminishing return effect on the makespan. Another finding is that the system with a large number of short storage aisles leads to higher throughput capacity than that with a small number of long storage aisles.

2285. Using Genomic Sequencing to Describe SARS-CoV-2 Transmission Dynamics in U.S. Major League Soccer Clubs

Abstract Background In 2020–2022, U.S. Major League Soccer (MLS) used SARS-CoV-2 mitigation protocols that included masking, social distancing, avoiding contact with others outside of training and games, testing, quarantine, and isolation. In addition to isolation for those who tested positive, a SARS-CoV-2 genomic sequencing strategy was developed to identify whether infections were associated with intra-league transmission. Methods Nasopharyngeal swabs were collected by MLS club medical staff from players and staff from February 2021 through September 2022. During this time, surveillance testing changed from daily to weekly to testing only symptomatic players and staff. SARS-CoV-2 positive samples were analyzed using amplicon-based whole genome sequencing. A phylogenetic tree was constructed using Nextstrain to visualize genomes from infected players and staff in the context of genomes available on GISAID circulating in the United States during corresponding time periods. To identify transmission links, all genomes were compared in a pairwise fashion. Genomes that were 0–2 nucleotides different were considered part of direct transmission clusters. Results Of 250 samples that were rtPCR positive for SARS-CoV-2, 215 (86%) were sequenced. Phylogenetic analysis showed a broad diversity of lineages, including some predominant overseas (e.g., AY.98.1). Pairwise comparison revealed SARS-CoV-2 sequences from 7 individuals appeared to be linked. These individuals were on 2 different MLS teams; there was an off-field exposure (dinner). Five (71%) had identical SARS-CoV-2 sequences; 2 had sequences that were 1 nucleotide different at the consensus level. Subconsensus genome analysis revealed that differences of 1 nucleotide were due to subconsensus mutations fluctuating below and above 50%, suggesting all 7 individuals were part of a transmission cluster. Phylogenetic analysis revealed that the sequences from the cluster were distinct from reference sequences and were likely a unique transmission chain. Conclusion SARS-CoV-2 transmission may occur within, and even between, professional sports teams. Pairwise comparison of individual genomes can provide improved granularity to identify clusters and understand SARS-CoV-2 transmission. Disclosures Davidson H. Hamer, MD, Kephera Diagnostics: Grant/Research Support|Takeda: Advisor/Consultant|Takeda: Grant/Research Support|Trinity Biotech, LLC: Advisor/Consultant|Valneva: Advisor/Consultant|Valneva: Grant/Research Support Daniel Bourque, MD, Kephera Diagnostics: Grant/Research Support