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The COVID-19 pandemic vaccination infrastructure was redeployed to address the Mpox epidemic. The Westchester County Department of Health coordinated an effective vaccine distribution, tracking, and data collection process with community partners with real-time feedback of operational challenges and updated public health directives. Westchester County, which comprises 9% of the New York State population, administered 24% (6770 doses) of JYNNEOS (smallpox and monkeypox vaccine) across the state. Among first-dose recipients, 13% were Black and 25% were Hispanic, approaching countywide US Census race and ethnicity breakdowns. The operational template designed during COVID-19 can be readily redeployed for subsequent epidemics of even seemingly dissimilar infections like Mpox.
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COVID-19 , Mpox , Humanos , Pandemias/prevención & control , New York/epidemiología , COVID-19/epidemiología , COVID-19/prevención & control , Brotes de Enfermedades/prevención & controlRESUMEN
Background: This report details how one large medical center in the Metropolitan New York area re-purposed a drive-through COVID-19 vaccination structure to handle a surge in Mpox cases in July 2022.Methods/Results: Simultaneous to on-going COVID -19 vaccination and testing, Mpox vaccination was rolled out in the same drive through structure. More than 1,820 Jynneos (Smallpox and Monkeypox Vaccine, Live, Non-replicating) vaccine dosages were delivered subcutaneously and then intradermally to 1,123 individuals through the open window of their vehicles, averaging 8-10 patients an hour. Five vaccine recipients suffered Mpox rash; there was no exposure among healthcare providers. Conclusion: Drive-through vaccination is an efficient model to be redeployed for future unexpected vaccine initiatives.
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Moderate heat stress negatively impacts fertility in sexually reproducing organisms at sublethal temperatures. These moderate heat stress effects are typically more pronounced in males. In some species, sperm production, quality and motility are the primary cause of male infertility during moderate heat stress. However, this is not the case in the model nematode Caenorhabditis elegans, where changes in mating behavior are the primary cause of fertility loss. We report that heat-stressed C. elegans males are more motivated to locate and remain on food and less motivated to leave food to find and mate with hermaphrodites than their unstressed counterparts. Heat-stressed males also demonstrate a reduction in motility that likely limits their ability to mate. Collectively these changes result in a dramatic reduction in reproductive success. The reduction in mate-searching behavior may be partially due to increased expression of the chemoreceptor odr-10 in the AWA sensory neurons, which is a marker for starvation in males. These results demonstrate that moderate heat stress may have profound and previously underappreciated effects on reproductive behaviors. As climate change continues to raise global temperatures, it will be imperative to understand how moderate heat stress affects behavioral and motility elements critical to reproduction.
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Proteínas de Caenorhabditis elegans , Infertilidad , Animales , Masculino , Caenorhabditis elegans/fisiología , Conducta Sexual Animal/fisiología , Semen , Reproducción/fisiología , Respuesta al Choque Térmico , Proteínas de Caenorhabditis elegans/metabolismoRESUMEN
Early in the 2022 Mpox (MPX) global outbreak, caseloads in the New York Metropolitan area climbed rapidly before other US urban areas. This case series summarizes the authors' clinical experience detecting and treating MPX, during a quickly evolving outbreak. Clinical outcomes were recorded with a focus on varied clinical presentation and outcomes such as complications and response to experimental tecovirimat therapy. A focal or multifocal rash was the most common presenting symptom in 91% of patients. Almost two-thirds (62%) of patients had anogenital involvement. Proctitis was one of the most painful presentations with 75% requiring antiviral treatment and three patients needing hospitalization for pain management. Most patients responded promptly to antiviral treatment with tecovirimat. Five out of 10 patients treated with tecovirimat reported symptom resolution within 48-72 h of therapy and another three saw resolution within first 96 h. Two patients had poor response to tecovirimat. This series includes the only reported case of an HIV positive, immunocompetent patient who experienced recurrent anal ulcers due to Mpox and required a second course of tecovirimat. Other unique presentations included urethritis, abscess formation and MPX infection postvaccination. Control of this current Mpox outbreak was possible due to timely diagnosis and the availability of both a licensed vaccine and an investigational drug.
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Mpox , Humanos , New York , Antivirales/uso terapéutico , Benzamidas , IsoindolesRESUMEN
BACKGROUND: Persistent cognitive, medical and psychiatric complaints have been extensively described after recovery from acute SARS-CoV-2 infection. OBJECTIVE: To describe neuropsychological, medical, psychiatric, and functional correlates of cognitive complaints experienced after recovery from acute COVID-19 infection. METHODS: Sixty participants underwent neuropsychological, psychiatric, medical, functional, and quality-of-life assessments 6-8 months after acute COVID-19. Those seeking care for cognitive complaints in a post-COVID-19 clinical program for post-acute symptoms of COVID-19 (clinical group, N = 32) were compared with those recruited from the community who were not seeking care (nonclinical, N = 28). A subset of participants underwent serological testing for proinflammatory cytokines C-reactive protein, interleukin-6, and tumor necrosis factor-α to explore correlations with neuropsychological, psychiatric, and medical variables. RESULTS: For the entire sample, 16 (27%) had extremely low test scores (less than second percentile on at least 1 neuropsychological test). The clinical group with cognitive complaints scored lower than age-adjusted population norms in tests of attention, processing speed, memory, and executive function and scored significantly more in the extremely low range than the nonclinical group (38% vs. 14%, P < 0.04). The clinical group also reported higher levels of depression, anxiety, fatigue, posttraumatic stress disorder, and functional difficulties and lower quality of life. In logistic regression analysis, scoring in the extremely low range was predicted by acute COVID-19 symptoms, current depression score, number of medical comorbidities, and subjective cognitive complaints in the areas of memory, language, and executive functions. Interleukin-6 correlated with acute COVID symptoms, number of medical comorbidities, fatigue, and inversely with measures of executive function. C-reactive protein correlated with current COVID symptoms and depression score but inversely with quality of life. CONCLUSION: Results suggest the existence of extremely low neuropsychological test performance experienced by some individuals months after acute COVID-19 infection, affecting multiple neurocognitive domains. This extremely low neuropsychological test performance is associated with worse acute COVID-19 symptoms, depression, medical comorbidities, functional complaints, and subjective cognitive complaints. Exploratory correlations with proinflammatory cytokines support further research into inflammatory mechanisms and viable treatments.
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COVID-19 , Proteína C-Reactiva , Estudios Transversales , Depresión , Fatiga/psicología , Humanos , Interleucina-6 , Calidad de Vida , SARS-CoV-2 , Factor de Necrosis Tumoral alfaAsunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Trasplante de Órganos , Complicaciones Posoperatorias/tratamiento farmacológico , Adulto , Anciano , COVID-19/etiología , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Clostridioides difficile infection (CDI) is prevalent in pediatric oncology patients, but the transmission risk to peers is unknown. In 224 children with CDI, multilocus sequence typing (MLST) identified only 7 alleged transmission events (18%) originating from children <3 years old. None of these events were corroborated by WGS.
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Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/transmisión , Preescolar , Clostridioides difficile/genética , Infecciones por Clostridium/epidemiología , Heces/microbiología , Humanos , Lactante , Recién Nacido , Tipificación de Secuencias Multilocus , Neoplasias/terapia , Estudios Retrospectivos , RibotipificaciónRESUMEN
The surveillance of health care-associated infection (HAI) is an essential element of the infection control program. While whole-genome sequencing (WGS) has widely been adopted for genomic surveillance, its data processing remains to be improved. Here, we propose a three-level data processing pipeline for the precision genomic surveillance of microorganisms without prior knowledge: species identification, multi-locus sequence typing (MLST), and sub-MLST clustering. The former two are closely connected to what have widely been used in current clinical microbiology laboratories, whereas the latter one provides significantly improved resolution and accuracy in genomic surveillance. Comparing to a broadly used reference-dependent alignment/mapping method and an annotation-dependent pan-/core-genome analysis, we implemented our reference- and annotation-independent, k-mer-based, simplified workflow to a collection of Acinetobacter and Enterococcus clinical isolates for tests. By taking both single nucleotide variants and genomic structural changes into account, the optimized k-mer-based pipeline demonstrated a global view of bacterial population structure in a rapid manner and discriminated the relatedness between bacterial isolates in more detail and precision. The newly developed WGS data processing pipeline would facilitate WGS application to the precision genomic surveillance of HAI. In addition, the results from such a WGS-based analysis would be useful for the precision laboratory diagnosis of infectious microorganisms.
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OBJECTIVE: To determine the effectiveness of ultraviolet (UV) environmental disinfection system on rates of hospital-acquired vancomycin-resistant enterococcus (VRE) and Clostridium difficile. DESIGN: Using active surveillance and an interrupted time-series design, hospital-acquired acquisition of VRE and C. difficile on a bone marrow transplant (BMT) unit were examined before and after implementation of terminal disinfection with UV on all rooms regardless of isolation status of patients. The main outcomes were hospital-based acquisition measured through (1) active surveillance: admission, weekly, and discharge screening for VRE and toxigenic C. difficile (TCD) and (2) clinical surveillance: incidence of VRE and CDI on the unit. SETTING: Bone marrow transplant unit at a tertiary-care cancer center.ParticipantsStem cell transplant (SCT) recipients.InterventionTerminal disinfection of all rooms with UV regardless of isolation status of patients. RESULTS: During the 20-month study period, 579 patients had 704 admissions to the BMT unit, and 2,160 surveillance tests were performed. No change in level or trend in the incidence of VRE (trend incidence rate ratio [IRR], 0.96; 95% confidence interval [CI], 0.81-1.14; level IRR, 1.34; 95% CI, 0.37-1.18) or C. difficile (trend IRR, 1.08; 95% CI, 0.89-1.31; level IRR, 0.51; 95% CI, 0.13-2.11) was observed after the intervention. CONCLUSIONS: Utilization of UV disinfection to supplement routine terminal cleaning of rooms was not effective in reducing hospital-acquired VRE and C. difficile among SCT recipients.
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Infecciones por Clostridium/prevención & control , Infección Hospitalaria/prevención & control , Desinfección/métodos , Infecciones por Bacterias Grampositivas/prevención & control , Rayos Ultravioleta , Trasplante de Médula Ósea , Clostridioides difficile/aislamiento & purificación , Clostridioides difficile/efectos de la radiación , Recuento de Colonia Microbiana , Humanos , Análisis de Series de Tiempo Interrumpido , New York , Habitaciones de Pacientes , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Enterococos Resistentes a la Vancomicina/efectos de la radiaciónRESUMEN
In 2015, Clostridium difficile testing rates among 30 US community, multispecialty, and cancer hospitals were 14.0, 16.3, and 33.9/1,000 patient-days, respectively. Pooled hospital onset rates were 0.56, 0.84, and 1.57/1,000 patient-days, respectively. Higher testing rates may artificially inflate reported rates of C. difficile infection. C. difficile surveillance should consider testing frequency.
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Clostridioides difficile , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/microbiología , Disparidades en el Estado de Salud , Técnicas Bacteriológicas , Clostridioides difficile/genética , Infecciones por Clostridium/diagnóstico , Hospitalización , Hospitales , Humanos , Técnicas de Amplificación de Ácido Nucleico , Vigilancia en Salud PúblicaRESUMEN
Complete genome sequences of four toxigenic Clostridium difficile isolates from patients in the lower Hudson Valley, New York, USA, were achieved. These isolates represent four common sequence types (ST1, ST2, ST8, and ST42) belonging to two distinct phylogenetic clades. All isolates have a 4.0- to 4.2-Mb circular chromosome, and one carries a phage.
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Strong founder effects resulting from human migration out of Africa have led to geographic variation in single nucleotide polymorphisms (SNPs) and microsatellites (MS) of the malaria parasite, Plasmodium falciparum. This is particularly striking in South America where two major founder populations of P. falciparum have been identified that are presumed to have arisen from the transatlantic slave trade. Given the importance of the major variant surface antigen of the blood stages of P. falciparum as both a virulence factor and target of immunity, we decided to investigate the population genetics of the genes encoding "Plasmodium falciparum Erythrocyte Membrane Protein 1" (Pf EMP1) among several countries in South America, in order to evaluate the transmission patterns of malaria in this continent. Deep sequencing of the DBLα domain of var genes from 128 P. falciparum isolates from five locations in South America was completed using a 454 high throughput sequencing protocol. Striking geographic variation in var DBLα sequences, similar to that seen for SNPs and MS markers, was observed. Colombia and French Guiana had distinct var DBLα sequences, whereas Peru and Venezuela showed an admixture. The importance of such geographic variation to herd immunity and malaria vaccination is discussed.
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We report here the incidental detection and complete genome sequence of a urinary Escherichia coli strain harboring mcr-1 and resistant to colistin in a New York patient returning from Portugal in 2016. This strain, with sequence type 1485 (ST1485), was a non-extended-spectrum beta-lactamase (ESBL) and non-carbapenemase producer and carried the mcr-1 gene on an IncHI2 plasmid.
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Existing theory on competition for hosts between pathogen strains has proposed that immune selection can lead to the maintenance of strain structure consisting of discrete, weakly overlapping antigenic repertoires. This prediction of strain theory has conceptual overlap with fundamental ideas in ecology on niche partitioning and limiting similarity between coexisting species in an ecosystem, which oppose the hypothesis of neutral coexistence. For Plasmodium falciparum, strain theory has been specifically proposed in relation to the major surface antigen of the blood stage, known as PfEMP1 and encoded by the multicopy multigene family known as the var genes. Deep sampling of the DBLα domain of var genes in the local population of Bakoumba, West Africa, was completed to define whether patterns of repertoire overlap support a role of immune selection under the opposing force of high outcrossing, a characteristic of areas of intense malaria transmission. Using a 454 high-throughput sequencing protocol, we report extremely high diversity of the DBLα domain and a large parasite population with DBLα repertoires structured into nonrandom patterns of overlap. Such population structure, significant for the high diversity of var genes that compose it at a local level, supports the existence of "strains" characterized by distinct var gene repertoires. Nonneutral, frequency-dependent competition would be at play and could underlie these patterns. With a computational experiment that simulates an intervention similar to mass drug administration, we argue that the observed repertoire structure matters for the antigenic var diversity of the parasite population remaining after intervention.
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Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Infecciones Asintomáticas , Niño , Preescolar , Estudios de Cohortes , Gabón/epidemiología , Variación Genética , Humanos , Lactante , Malaria Falciparum/epidemiología , Análisis de Secuencia de ADNRESUMEN
The free-living protozoan Acanthamoeba is an opportunistic pathogen that is ubiquitous in our environment. However, its role in affecting indoor air quality and ill-health of indoor occupants is relatively unknown. The present study investigated the presence of Acanthamoeba from the ventilation system and its correlation with other indoor air quality parameters, used in the industry code of practice and its potential as an indicator for indoor air quality. Indoor air quality assessments were carried out in nine commercial buildings with approval from the building management, and the parameters assessed were as recommended by the Department of Occupational Safety and Health. The presence of Acanthamoeba was determined through dust swabs from the ventilation system and indoor furniture. Logistic regression was performed to study the correlation between assessed parameters and occupants' complaints. A total of 107 sampling points were assessed and 40.2% of the supplying air diffuser and blowing fan and 15% of the furniture were positive for cysts. There was a significant correlation between Acanthamoeba detected from the ventilation system with ambient total fungus count (r=0.327; p=0.01) and respirable particulates (r=0.276; p=0.01). Occupants' sick building syndrome experience also correlated with the presence of Acanthamoeba in the ventilation system (r=0.361; p=0.01) and those detected on the furniture (r=0.290; p=0.01). Logistic regression showed that there was a five-fold probability of sick building syndrome among occupants when Acanthamoeba was detected in the ventilation system.
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Acanthamoeba/aislamiento & purificación , Contaminación del Aire Interior/análisis , Amebiasis/epidemiología , Síndrome del Edificio Enfermo , Ventilación , Humanos , Modelos Logísticos , Infecciones OportunistasRESUMEN
Complete genome sequences of nine enterovirus D68 (EV-D68) strains from patients in New York were obtained in 2016 by metagenomic next-generation sequencing. Comparative genomic analysis suggests that a new subclade B3, with ~4.5% nucleotide divergence from subclade B1 strains causing the 2014 outbreak, is circulating in the United States in 2016.
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BACKGROUND: Amplicon pyrosequencing targets a known genetic region and thus inherently produces reads highly anticipated to have certain features, such as conserved nucleotide sequence, and in the case of protein coding DNA, an open reading frame. Pyrosequencing errors, consisting mainly of nucleotide insertions and deletions, are on the other hand likely to disrupt open reading frames. Such an inverse relationship between errors and expectation based on prior knowledge can be used advantageously to guide the process known as basecalling, i.e. the inference of nucleotide sequence from raw sequencing data. RESULTS: The new basecalling method described here, named Multipass, implements a probabilistic framework for working with the raw flowgrams obtained by pyrosequencing. For each sequence variant Multipass calculates the likelihood and nucleotide sequence of several most likely sequences given the flowgram data. This probabilistic approach enables integration of basecalling into a larger model where other parameters can be incorporated, such as the likelihood for observing a full-length open reading frame at the targeted region. We apply the method to 454 amplicon pyrosequencing data obtained from a malaria virulence gene family, where Multipass generates 20 % more error-free sequences than current state of the art methods, and provides sequence characteristics that allow generation of a set of high confidence error-free sequences. CONCLUSIONS: This novel method can be used to increase accuracy of existing and future amplicon sequencing data, particularly where extensive prior knowledge is available about the obtained sequences, for example in analysis of the immunoglobulin VDJ region where Multipass can be combined with a model for the known recombining germline genes. Multipass is available for Roche 454 data at http://www.cbs.dtu.dk/services/MultiPass-1.0 , and the concept can potentially be implemented for other sequencing technologies as well.
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ADN Protozoario/aislamiento & purificación , Análisis de Secuencia de ADN , Algoritmos , ADN Protozoario/genética , Modelos Moleculares , Sistemas de Lectura Abierta , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Alineación de SecuenciaRESUMEN
BACKGROUND: Recent studies described an increase in acute kidney injury when high dose gentamicin was included in perioperative prophylaxis for orthopedic surgeries. To this effect, we compared the rate of nephrotoxicity for selected orthopedic surgeries where gentamicin was included (Gentamicin Group) to those where it was not included (Control Group) for perioperative prophylaxis and evaluated risk factors for nephrotoxicity. METHODS: Spine, hip and knee surgeries performed between April 2011 and December 2013 were reviewed retrospectively. Gentamicin was given to eligible patients based on age, weight and Creatinine Clearance. Nephrotoxicity was assessed using Risk, Injury, Failure, Loss, End-stage kidney disease (RIFLE) criteria. RESULTS: Among selected surgeries (N = 1590 in Gentamicin Group: hip = 926, spine = 600, knee = 64; N = 2587 in CONTROL GROUP: hip = 980, spine = 902, knee = 705), patients' body weight, serum creatinine, comorbidities and surgery duration were similar in Gentamicin Group and CONTROL GROUP. Gentamicin median dose was 4.5 mg/kg of dosing weight. Nephrotoxicity rate was 2.5% in Gentamicin Group and 1.8% in CONTROL GROUP, p = 0.17. Most cases of nephrotoxicity were Risk category by RIFLE criteria (67% in Gentamicin Group and 72% in CONTROL GROUP, p = 0.49). In logistic regression, risk factors for nephrotoxicity were hospital stay >1 day prior to surgery (odds ratio = 8.1; 95% confidence interval = 2.25-28.97, p = 0.001), knee or hip surgery (odds ratio = 4.7; 95% confidence interval = 2.9-9.48, p = 0.0005) and diabetes (odds ratio = 1.95; 95% confidence interval = 1.13-3.35, p = 0.016). Receipt of gentamicin was not an independent predictor of nephrotoxicity (odds ratio = 1.5; 95% confidence interval = 0.97-2.35, p = 0.07). CONCLUSION: In this cohort, rate of nephrotoxicity was similar between Gentamicin Group and Control Group. Single high dose gentamicin is a safe and acceptable option for perioperative prophylaxis in eligible patients undergoing orthopedic surgeries.
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Piperacillin-tazobactam (PTZ) is frequently used as empirical and targeted therapy for Gram-negative sepsis. Time-dependent killing properties of PTZ support the use of extended-infusion (EI) dosing; however, studies have shown inconsistent benefits of EI PTZ treatment on clinical outcomes. We performed a retrospective cohort study of adult patients who received EI PTZ treatment and historical controls who received standard-infusion (SI) PTZ treatment for presumed sepsis syndromes. Data on mortality rates, clinical outcomes, length of stay (LOS), and disease severity were obtained. A total of 843 patients (662 with EI treatment and 181 with SI treatment) were available for analysis. Baseline characteristics of the two groups were similar, except for fewer female patients receiving EI treatment. No significant differences between the EI and SI groups in inpatient mortality rates (10.9% versus 13.8%; P = 0.282), overall LOS (10 versus 12 days; P = 0.171), intensive care unit (ICU) LOS (7 versus 6 days; P = 0.061), or clinical failure rates (18.4% versus 19.9%; P = 0.756) were observed. However, the duration of PTZ therapy was shorter in the EI group (5 versus 6 days; P < 0.001). Among ICU patients, no significant differences in outcomes between the EI and SI groups were observed. Patients with urinary or intra-abdominal infections had lower mortality and clinical failure rates when receiving EI PTZ treatment. We did not observe significant differences in inpatient mortality rates, overall LOS, ICU LOS, or clinical failure rates between patients receiving EI PTZ treatment and patients receiving SI PTZ treatment. Patients receiving EI PTZ treatment had a shorter duration of PTZ therapy than did patients receiving SI treatment, and EI dosing may provide cost savings to hospitals.
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Antibacterianos/uso terapéutico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infusiones Intravenosas/métodos , Ácido Penicilánico/análogos & derivados , Sepsis/tratamiento farmacológico , Anciano , Antibacterianos/economía , Análisis Costo-Beneficio , Femenino , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/patogenicidad , Bacterias Gramnegativas/fisiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/mortalidad , Infecciones por Bacterias Gramnegativas/patología , Humanos , Tiempo de Internación/economía , Masculino , Ácido Penicilánico/economía , Ácido Penicilánico/uso terapéutico , Piperacilina/economía , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam , Estudios Retrospectivos , Sepsis/microbiología , Sepsis/mortalidad , Sepsis/patología , Análisis de Supervivencia , Síndrome , Atención Terciaria de Salud/economíaRESUMEN
BACKGROUND: The var genes of the human malaria parasite Plasmodium falciparum are highly polymorphic loci coding for the erythrocyte membrane proteins 1 (PfEMP1), which are responsible for the cytoaherence of P. falciparum infected red blood cells to the human vasculature. Cytoadhesion, coupled with differential expression of var genes, contributes to virulence and allows the parasite to establish chronic infections by evading detection from the host's immune system. Although studying genetic diversity is a major focus of recent work on the var genes, little is known about the gene family's origin and evolutionary history. RESULTS: Using a novel hidden Markov model-based approach and var sequences assembled from additional isolates and species, we are able to reveal elements of both the early evolution of the var genes as well as recent diversifying events. We compare sequences of the var gene DBLα domains from divergent isolates of P. falciparum (3D7 and HB3), and a closely-related species, Plasmodium reichenowi. We find that the gene family is equally large in P. reichenowi and P. falciparum -- with a minimum of 51 var genes in the P. reichenowi genome (compared to 61 in 3D7 and a minimum of 48 in HB3). In addition, we are able to define large, continuous blocks of homologous sequence among P. falciparum and P. reichenowi var gene DBLα domains. These results reveal that the contemporary structure of the var gene family was present before the divergence of P. falciparum and P. reichenowi, estimated to be between 2.5 to 6 million years ago. We also reveal that recombination has played an important and traceable role in both the establishment, and the maintenance, of diversity in the sequences. CONCLUSIONS: Despite the remarkable diversity and rapid evolution found in these loci within and among P. falciparum populations, the basic structure of these domains and the gene family is surprisingly old and stable. Revealing a common structure as well as conserved sequence among two species also has implications for developing new primate-parasite models for studying the pathology and immunology of falciparum malaria, and for studying the population genetics of var genes and associated virulence phenotypes.