Angela M Caliendo

Alpert Medical School - Brown University, Providence, Rhode Island, United States

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Publications (196)726.08 Total impact

  • Soya S Sam · Jaclynn R Kurpewski · Susan Cu-Uvin · Angela M Caliendo
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    ABSTRACT: Quantification of HIV-1 RNA has become the standard of care in the clinical management of HIV-1 infected individuals. The objective of the study was to evaluate performance characteristics and relative work-flow of the Aptima HIV-1 Quant Dx Assay in comparison with the Abbott RealTime HIV-1 assay using plasma and cervicovaginal lavage specimens (CVL). Assay performance was evaluated using AcroMetrix HIV-1 panel, AcroMetrix positive controls, Qnostics and SeraCare HIV-1 evaluation panels, 208 clinical plasma samples and 205 matched CVL specimens on Panther and m2000 platforms. The Aptima assay demonstrated good linearity over the quantification range tested (2-5 log 10 copies/ml) and there was strong linear correlation between the assays (R2=0.99) with a comparable coefficient of variance
    No preview · Article · Feb 2016 · Journal of clinical microbiology
  • Angela M. Caliendo · Kimberly E. Hanson
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    ABSTRACT: Since the Food and Drug Administration (FDA) released its draft guidance on the regulation of laboratory-developed tests (LDTs) in October 2014, there has been a flurry of responses from commercial and hospital based laboratory directors, clinicians, professional organizations and diagnostic companies. The FDA defines an LDT as an “ in vitro diagnostic device that is intended for clinical use and is designed, manufactured, and used within a single laboratory”. The draft guidance outlines a risk-based approach, with oversight of high risk and moderate risk tests being phased in over nine years. High risk tests would be regulated first and require a premarket approval. Subsequently, moderate risk tests would require a 510(k) and low risk tests would need only to be registered. Oversight discretion will be exercised for LDTs focused on rare diseases (defined as fewer than 4,000 tests, not cases, per year nationally) and unmet clinical needs (defined as those tests for which there is no alternative FDA cleared or approved test). There was an open comment period followed by a public hearing in early January of 2015 and we are currently awaiting the final decision regarding the regulation of LDTs. Given that LDTs have been developed by many laboratories and are essential for the diagnosis and monitoring of an array of infectious diseases, changes in their regulation with have far reaching implications for clinical microbiology laboratories. In this point-counterpoint Dr. Angela Caliendo discusses the potential benefits of the FDA guidance for LDTs while Dr. Kim Hanson discusses the concerns associated with implementing the guidance and why these regulations may not improve clinical care.
    No preview · Article · Jan 2016 · Journal of Clinical Microbiology
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    ABSTRACT: Invasive pulmonary aspergillosis (IPA) is an opportunistic fungal infection in patients undergoing chemotherapy for hematological malignancy, hematopoietic stem cell transplant, or other forms of immunosuppression. In this group, Aspergillus infections account for the majority of deaths due to mold pathogens. Although early detection is associated with improved outcomes, current diagnostic regimens lack sensitivity and specificity. Patients undergoing chemotherapy, stem cell transplantation and lung transplantation were enrolled in a multi-site prospective observational trial. Proven and probable IPA cases and matched controls were subjected to discovery proteomics analyses using a biofluid analysis platform, fractionating plasma into reproducible protein and peptide pools. From 556 spots identified by 2D gel electrophoresis, 66 differentially expressed post-translationally modified plasma proteins were identified in the leukemic subgroup only. This protein group was rich in complement components, acute-phase reactants and coagulation factors. Low molecular weight peptides corresponding to abundant plasma proteins were identified. A candidate marker panel of host response (9 plasma proteins, 4 peptides), fungal polysaccharides (galactomannan), and cell wall components (β-D glucan) were selected by statistical filtering for patients with leukemia as a primary underlying diagnosis. Quantitative measurements were developed to qualify the differential expression of the candidate host response proteins using selective reaction monitoring mass spectrometry assays, and then applied to a separate cohort of 57 patients with leukemia. In this verification cohort, a machine learning ensemble-based algorithm, generalized pathseeker (GPS) produced a greater case classification accuracy than galactomannan (GM) or host proteins alone. In conclusion, Integration of host response proteins with GM improves the diagnostic detection of probable IPA in patients undergoing treatment for hematologic malignancy. Upon further validation, early detection of probable IPA in leukemia treatment will provide opportunities for earlier interventions and interventional clinical trials.
    Preview · Article · Nov 2015 · PLoS ONE
  • R T Hayden · J Preiksaitis · Y Tong · X Pang · Y Sun · L Tang · L Cook · S Pounds · J Fryer · A M Caliendo
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    ABSTRACT: Quantitative detection of cytomegalovirus (CMV) DNA has become a standard part of care for many groups of immunocompromised patients; recent development of the 1st WHO international Standard for human CMV DNA has raised hopes of reducing inter-laboratory variability of results. Commutability of reference material has been shown to be necessary if such material is to reduce variability among laboratories. Here we evaluated commutability of the WHO standard using ten different real-time quantitative CMV PCR assays run by eight different laboratories. Test panels, including aliquots of 50 patient samples (40 positive, 10 negative), lyophilized CMV standard, were run, with each testing center using its own quantitative calibrators, reagents, and nucleic acid extraction methods. Commutability was assessed both on a pairwise basis and over the entire group of assays, using linear regression and correspondence analyses. Commutability of the WHO material differed among the tests that were evaluated, and those differences appeared to vary depending on the method of statistical analysis used and the cohort of assays included in the analysis. Depending on the methodology used, the WHO material showed poor or absent commutability with up to 50% of assays. Determination of commutability may require a multi-faceted approach; the lack of commutability seen when using the WHO standard with several of the assays here suggests that further work is needed to bring us towards true consensus. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
    No preview · Article · Aug 2015 · Journal of clinical microbiology
  • Angela M Caliendo

    No preview · Article · Jul 2015 · Clinical Infectious Diseases
  • R. T. Hayden · Z. Gu · S. S. Sam · Y. Sun · L. Tang · S. Pounds · A. M. Caliendo

    No preview · Article · Feb 2015 · Journal of Clinical Microbiology
  • Hayden RT · Gu Z · Sam SS · Sun Y · Tang L · Pounds S · Caliendo AM
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    ABSTRACT: The recent development of the 1st WHO International Standard for human cytomegalovirus (CMV) and introduction of commercially produced secondary standards has raised hopes of improved agreement among laboratories performing quantitative CMV PCR. However, data are lacking to evaluate the trueness and uniformity of secondary standards and the consistency of results achieved when these materials are run on various assays. Three concentrations of each of three commercially prepared secondary CMV standards were tested in quadruplicate by three real-time and two digital PCR methods. Mean results were compared in a pairwise fashion with nominal values provided by each manufacturer. Agreement of results among all methods was also assessed for each sample and for like concentrations of each standard. The relationship between nominal values of standards and measured values varied depending upon assay used and manufacturer of standards, with the degree of bias ranging from +0.6 to -1.0 log10(IU/ml). The mean digital PCR result differed significantly among the secondary standards, as did the results of real-time PCR, particularly when plotted against nominal log10IU values. Commercially available quantitative secondary CMV standards produce variable results when tested by different real-time and digital PCR assays, with varying magnitudes of bias compared to nominal values. These findings suggest that the use of such materials may not achieve the intended uniformity among laboratories measuring CMV viral load, as envisioned by adaptation of the WHO standard.
    No preview · Article · Feb 2015 · Journal of Clinical Microbiology
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    ABSTRACT: Introduction: For developing countries, sexually transmitted infections (STIs) and their complications are ranked in the top 5 disease categories for which adults seek medical treatment. Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) are the three most common STIs worldwide, with TV accounting for over half of the cases. In developing countries, traditional methods for diagnosing STIs are laborious, often not very sensitive, and have a long turnaround time with most recent commercially available diagnostic tests targeting one or, at most, two of these STIs at a time. Here, we describe the development of a highly sensitive, rapid and affordable sample-to-answer multiplex PCR-based assay for the simultaneous detection of Trichomonas vaginalis, Neisseria gonorrhoeae, and Chlamydia trachomatis. Materials and methods: We designed a multiplex PCR assay for the detection of 4 targets (CT, TV, NG, and process/PCR control) using melt curve analysis. To establish the limit of detection (LOD) for each pathogen, we used previously extracted and quantified TV, NG, and CT genomic DNA (Vircell, Spain). For each target, the LOD was determined by lowering its copy number while increasing the other two STI loads in a stepwise fashion. The process/PCR control remained constant in the optimized assay and was spiked into each sample before extraction. For a concordance study, we tested urine, vaginal and rectal swab specimens from 26 patients positive for one or more of the tested STIs. In addition, 56 liquid cytology specimens (Thinprep) were used to assess specificity. Results: This assay has a turnaround time of less than 2h and has a limit of detection as low as 7-31 copies for each STI in the presence of the other 2 targets. Our assay also demonstrated 100% concordance with 26 known clinical samples from urine, vaginal and rectal swab specimens. TV, NG, CT, and our process/PCR control were consistently identified at 78°C, 82.3°C, 85.7°C, and ~92°C, respectively. When applied to DNA extracted from residual Thinprep specimens, the assay was negative in 54/56 samples. Two samples were found to be co-infected with CT. Conclusions: Our multiplex assay combines a rapid and cost-effective approach to molecular diagnostics with the versatility required for use within a variety of laboratory settings. These performance characteristics make this multiplex STI assay highly suitable for use in a clinical laboratory.
    No preview · Article · Jan 2015 · Experimental and Molecular Pathology
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    ABSTRACT: Objective:To evaluate the efficacy of a brief, phone counseling Prevention Maintenance Intervention (PMI) to sustain STI/HIV-preventive behaviors and reduce incident STIs over a 36-month follow-up. Design:A two-arm randomized controlled supplemental treatment trial Setting:Three clinics in Atlanta, Georgia. Participants:African-American adolescent females, 14-20 years, (N=701). Intervention:Participants in the experimental condition received an adapted CDC-defined evidence-based STI/HIV intervention (HORIZONS) and a PMI consisting of brief, tailored phone counseling every 8 weeks over 36-months. Comparison condition participants received HORIZONS and a time- and dose-consistent PMI focused on general health. Main Outcome Measure(s):Primary outcomes were proportion of participants with a laboratory-confirmed chlamydial or gonococcal infection. Behavioral outcomes include: (1) proportion of condom-protected sex acts (2) number of sexual episodes in which participants engaged in sexual intercourse while high on drugs/alcohol, and (3) number of vaginal sex partners. Results: Over 36-months follow-up, fewer participants in the experimental condition had incident chlamydial (94 versus 104; RR = 0.47; 95%CI 0.25 to 0.89; p=.02) and gonococcal infections (48 versus 54; RR = 0.39; 95%CI 0.14 to 1.04; p=.060). A dose effect was observed; participants completing more phone contacts had a lower risk of chlamydial infection (RR= 0.94, 95%CI 0.89, 0.99; p=0.049). Participants in the experimental condition reported a higher proportion of condom-protected sex acts (mean difference6 months=.08; 95%CI 0.06, 0.10; p=0.036), and fewer episodes of sex while high on alcohol/drugs (mean difference=-0.61; 95%CI -0.98,-0.24; p=0.0001). Conclusions and Relevance: Sustaining the long-term impact of HIV interventions is achievable with brief, tailored phone counseling.
    No preview · Conference Paper · Nov 2014
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    Preview · Article · Nov 2014 · Journal of Clinical Microbiology
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    ABSTRACT: Little is known about why some adolescents with internalizing symptoms engage in sexual behaviors that increase their risk for HIV. This study tested a mediation model of internalizing symptoms and safe sex intentions among adolescents receiving mental health treatment. Self-efficacy for HIV prevention, HIV knowledge, and worry about HIV were hypothesized to mediate associations between internalizing symptoms and safe sex intentions among sexually active and non-active adolescents receiving mental health treatment (N = 893, M age = 14.9). Significant indirect effects from internalizing symptoms to safe sex intentions varied according to sexual experience: for sexually non-active adolescents, HIV worry and knowledge mediated this link, whereas for sexually active adolescents, HIV self-efficacy was the significant mediator. Increasing both HIV knowledge and self-efficacy for HIV prevention are important targets for HIV prevention with adolescents with internalizing symptoms, and careful attention should be paid towards targeting these interventions to sexually experienced and inexperienced youth.
    Full-text · Article · Nov 2014 · Children and Youth Services Review

  • No preview · Conference Paper · Oct 2014
  • Conference Paper: Interactive Panelist

    No preview · Conference Paper · Oct 2014
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    ABSTRACT: Importance Postnatal cytomegalovirus (CMV) infection can cause serious morbidity and mortality in very low-birth-weight (VLBW) infants. The primary sources of postnatal CMV infection in this population are breast milk and blood transfusion. The current risks attributable to these vectors, as well as the efficacy of approaches to prevent CMV transmission, are poorly characterized.Objective To estimate the risk of postnatal CMV transmission from 2 sources: (1) transfusion of CMV-seronegative and leukoreduced blood and (2) maternal breast milk.Design, Setting, and Participants A prospective, multicenter birth-cohort study was conducted from January 2010 to June 2013 at 3 neonatal intensive care units (2 academically affiliated and 1 private) in Atlanta, Georgia. Cytomegalovirus serologic testing of enrolled mothers was performed to determine their status. Cytomegalovirus nucleic acid testing (NAT) of transfused blood components and breast milk was performed to identify sources of CMV transmission. A total of 539 VLBW infants (birth weight, ≤1500 g) who had not received a blood transfusion were enrolled, with their mothers (n = 462), within 5 days of birth. The infants underwent serum and urine CMV NAT at birth to evaluate congenital infection and surveillance CMV NAT at 5 additional intervals between birth and 90 days, discharge, or death.Exposures Blood transfusion and breast milk feeding.Main Outcomes and Measures Cumulative incidence of postnatal CMV infection, detected by serum or urine NAT.Results The seroprevalence of CMV among the 462 enrolled mothers was 76.2% (n = 352). Among the 539 VLBW infants, the cumulative incidence of postnatal CMV infection at 12 weeks was 6.9% (95% CI, 4.2%-9.2%); 5 of 29 infants (17.2%) with postnatal CMV infection developed symptomatic disease or died. A total of 2061 transfusions were administered among 57.5% (n = 310) of the infants; none of the CMV infections was linked to transfusion, resulting in a CMV infection incidence of 0.0% (95% CI, 0.0%-0.3%) per unit of CMV-seronegative and leukoreduced blood. Twenty-seven of 28 postnatal infections occurred among infants fed CMV-positive breast milk (12-week incidence, 15.3%; 95% CI, 9.3%-20.2%).Conclusions and Relevance Transfusion of CMV-seronegative and leukoreduced blood products effectively prevents transmission of CMV to VLBW infants. Among infants whose care is managed with this transfusion approach, maternal breast milk is the primary source of postnatal CMV infection.Trial Registration clinicaltrials.gov Identifier: NCT00907686
    Full-text · Article · Sep 2014 · JAMA Pediatrics
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    ABSTRACT: Importance Behavioral change interventions have demonstrated short-term efficacy in reducing sexually transmitted infection (STI)/human immunodeficiency virus (HIV) risk behaviors; however, few have demonstrated long-term efficacy.Objective To evaluate the efficacy of a telephone counseling prevention maintenance intervention (PMI) to sustain STI/HIV-preventive behaviors and reduce incident STIs during a 36-month follow-up.Design, Setting, and Participants In a 2-arm randomized supplemental treatment trial at 3 clinics serving predominantly minority adolescents in Atlanta, Georgia, 701 African American adolescent girls aged 14 to 20 years received a primary treatment and subsequently received a different (supplemental) treatment (PMI) to enhance effects of the primary treatment.Interventions Participants in the experimental condition (n = 342) received an adapted evidence-based STI/HIV intervention (HORIZONS) and a PMI consisting of brief telephone contacts every 8 weeks over 36 months to reinforce and complement prevention messages. Comparison-condition participants (n = 359) received HORIZONS and a time- and dose-consistent PMI focused on general health.Main Outcomes and Measures The primary outcomes were percentage of participants with a laboratory-confirmed incident chlamydial infection and percentage of participants with a laboratory-confirmed gonococcal infection during the 36-month follow-up. Behavioral outcomes included the following: (1) proportion of condom-protected sexual acts in the 6 months and 90 days prior to assessments; (2) number of sexual episodes during the past 90 days in which participants engaged in sexual intercourse while high on drugs and/or alcohol; and (3) number of vaginal sex partners in the 6 months prior to assessments.Results During the 36-month follow-up, fewer participants in the experimental condition than in the comparison condition had incident chlamydial infections (94 vs 104 participants, respectively; risk ratio = 0.50; 95% CI, 0.28 to 0.88; P = .02) and gonococcal infections (48 vs 54 participants, respectively; risk ratio = 0.40; 95% CI, 0.15 to 1.02; P = .06). Participants completing more telephone contacts had a lower risk of chlamydial infection (risk ratio = 0.95; 95% CI, 0.90 to 1.00; P = .05). Participants in the experimental condition reported a higher proportion of condom-protected sexual acts in the 90 days (mean difference = 0.08; 95% CI, 0.06 to 0.11; P = .02) and 6 months (mean difference = 0.08; 95% CI, 0.06 to 0.10; P = .04) prior to assessments and fewer episodes of sexual acts while high on drugs and/or alcohol (mean difference = −0.61; 95% CI, −0.98 to −0.24; P < .001).Conclusions and Relevance Sustaining the long-term impact of an STI/HIV intervention is achievable with brief, tailored telephone counseling.Trial Registration clinicaltrials.gov Identifier: NCT00279799
    No preview · Article · Aug 2014 · JAMA Pediatrics
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    ABSTRACT: Objective: To quantify HIV viral load within the alveolar macrophage in a cohort of healthy HIV-infected subjects who did not have medical co-morbidities or smoke cigarettes, and to determine if alveolar macrophage proviral DNA was associated with alveolar macrophage phagocytic immune dysfunction. Design: Prospective cross-sectional study Methods: We enrolled 23 subjects who underwent bronchoscopy and bronchoalveolar lavage. Alveolar macrophages were isolated and HIV-1 RNA was quantified in the cells using the Abbott RealTime HIV-1 Assay. Proviral DNA was qualitatively measured using a modified version of the HIV-1 RNA assay. Phagocytosis measured by incubating alveolar macrophages with FITC-labeled S. aureus and determining fluorescence with a Zeiss inverted microscope. Phagocytic index was calculated as (% positive cells x mean channel fluorescence)/100. Results: 16 subjects had (+) proviral DNA and 7 had (-) proviral DNA in their alveolar macrophages. 100% of all subjects in both groups were on HAART. The median plasma viral load was 0 in both groups. HIV-1-infected subjects with (+) proviral DNA in their alveolar macrophages had a significantly lower median alveolar macrophage phagocytic index compared to those with (-) proviral DNA in their alveolar macrophages [11.8 (IQR 4.8-39.0) vs. 64.9 (IQR 14.0-166.0), p=0.05]. Conclusions: Alveolar macrophages harbor HIV even in otherwise healthy subjects with undetectable plasma viral loads, representing a potential reservoir for the virus. In addition, HIV viral replication within the macrophage may impair phagocytosis and other immune functions in the lung, leading to an increased risk for lung infection.
    No preview · Article · Aug 2014 · AIDS Research and Human Retroviruses
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    ABSTRACT: Invasive aspergillosis is a difficult-to-diagnose infection with a high mortality rate that affects high-risk groups such as patients with neutropenia and hematologic malignancies. We performed a bivariate meta-analysis of diagnostic data for an Aspergillus sp. PCR assay with blood specimens from high-risk hematology patients. We included all studies involving human subjects that assessed the performance of any PCR assay for invasive aspergillosis in whole blood or serum and that used the European Organization for the treatment of Cancer/Mycoses Study Group criteria as a reference standard. Three investigators independently searched the literature for eligible studies and extracted the data. Out of a total of 37 studies, 25 met strict quality criteria and were included in our evidence synthesis. Twenty-five studies with 2,595 patients were analyzed. The pooled diagnostic performance of whole-blood and serum PCR assays was moderate, with a sensitivity and specificity of 84% (95% confidence interval [CI], 75 to 91%) and 76% (95% CI, 65 to 84%), respectively, suggesting that a positive or negative result is unable, on its own, to confirm or exclude a suspected infection. The performance of a PCR assay of serum was not significantly different from that of whole blood. Notably, at least two positive PCR test results were found to have a specificity of 95% and a sensitivity of 64% for invasive infection, achieving a high positive likelihood ratio of 12.8. Importantly, the European Aspergillus PCR Initiative (EAPCRI) recommendations improved the performance of the PCR even further when at least two positive specimens were used to define PCR positivity. In conclusion, two positive PCR results should be considered highly indicative of an active Aspergillus sp. infection. Use of the EAPCRI recommendations by clinical laboratories can further enhance PCR performance.
    Preview · Article · Aug 2014 · Journal of Clinical Microbiology
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    ABSTRACT: Objectives: To determine whether rhinovirus (RV) species is associated with more severe clinical illness in adults. Methods: Seventy-two RV-positive viral respiratory samples from adult patients were sequenced and analyzed phylogenetically after reverse transcriptase polymerase chain reaction of the region spanning the VP4 gene and 5' terminus of the VP2 gene. The clinical features and severity of illness associated with the different RV species were compared. Results: Phylogenetic analysis identified three distinct clusters as RV-A (54%), B (11%), or C (35%) species. In an unadjusted model, patients with RV-B infection were significantly more likely to have the composite outcome variable of death or intensive care unit admission (P=.03), but this effect diminished when controlling for patient sex. A logistic model of the relationship between RV species and adverse outcomes produced nonsignificant odds ratios when controlling for patient sex. Conclusions: Infection with RV-A or RV-B was associated with greater severity of illness in our adult population; however, the association disappeared after controlling for confounders.
    Full-text · Article · Aug 2014 · American Journal of Clinical Pathology
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    ABSTRACT: Invasive fungal infections constitute a serious threat to an ever-growing population of immunocompromised individuals and other individuals at risk. Traditional diagnostic methods, such as histopathology and culture, which are still considered the gold standards, have low sensitivity, which underscores the need for the development of new means of detecting fungal infectious agents. Indeed, novel serologic and molecular techniques have been developed and are currently under clinical evaluation. Tests like the galactomannan antigen test for aspergillosis and the β-glucan test for invasive Candida spp. and molds, as well as other antigen and antibody tests, for Cryptococcus spp., Pneumocystis spp., and dimorphic fungi, have already been established as important diagnostic approaches and are implemented in routine clinical practice. On the other hand, PCR and other molecular approaches, such as matrix-assisted laser desorption ionization (MALDI) and fluorescence in situ hybridization (FISH), have proved promising in clinical trials but still need to undergo standardization before their clinical use can become widespread. The purpose of this review is to highlight the different diagnostic approaches that are currently utilized or under development for invasive fungal infections and to identify their performance characteristics and the challenges associated with their use.
    Preview · Article · Jul 2014 · Clinical Microbiology Reviews

  • No preview · Article · May 2014 · Clinical Infectious Diseases

Publication Stats

7k Citations
726.08 Total Impact Points

Institutions

  • 1997-2016
    • Alpert Medical School - Brown University
      • Department of Medicine
      Providence, Rhode Island, United States
  • 2001-2015
    • Brown University
      • Department of Medicine
      Providence, Rhode Island, United States
  • 2001-2014
    • Emory University
      • • Department of Pathology and Laboratory Medicine
      • • Division of Infectious Diseases
      Atlanta, Georgia, United States
  • 2013
    • Vanderbilt University
      Нашвилл, Michigan, United States
  • 2011
    • Johns Hopkins Medicine
      • Department of Pathology
      Baltimore, Maryland, United States
  • 2008
    • United States Army Medical Research Institute for Infectious Diseases
      Фредерик, Maryland, United States
  • 2004
    • Eastern Virginia Medical School
      Norfolk, Virginia, United States
  • 2000-2002
    • Harvard University
      Cambridge, Massachusetts, United States
  • 1999-2002
    • University of Toronto
      • Department of Medicine
      Toronto, Ontario, Canada
  • 1994-2000
    • Massachusetts General Hospital
      • • Department of Pathology
      • • Microbiology Laboratory
      • • Pediatric Infectious Disease Unit
      Boston, Massachusetts, United States
  • 1994-1997
    • Harvard Medical School
      • • Department of Medicine
      • • Department of Pathology
      Boston, Massachusetts, United States