Elena Grigorenko

Seasonal variation of respiratory pathogen colonization in asymptomatic health care professionals: A single-center, cross-sectional, 2-season observational study

Background The purpose of this study was to determine the seasonal variance of potentially pathogenic bacterial and viral organisms in nasopharyngeal specimens obtained from asymptomatic health care professionals (HCPs) during the 2014 winter and summer months. Methods Nasopharyngeal specimens from 100 HCPs were collected from Huntsville Hospital (Huntsville, AL) during the winter and from 100 HCPs during the summer. All subjects were tested for 22 viruses and 19 bacteria using Target Enriched Multiplex Polymerase Chain Reaction. Both seasonal cohorts were composed of students, nurses, physicians, and residents. Results Of the 100 HCPs tested during the winter, 34 subjects were colonized with at least 1 bacterium, and 11 tested positive for at least 1 virus. Methicillin-resistant Staphylococcus aureus (MRSA), Moraxella catarrhalis, and coronavirus were the most frequently detected potentially infectious agents. Of the 100 HCPs tested during the summer, 37 tested positive for at least 1 bacterium, and 4 tested positive for a viral agent. The most prevalent bacteria were MRSA and Klebsiella pneumonia. Conclusion Nasopharyngeal carriage among asymptomatic HCPs was common, but the frequency and presence of potential pathogens varied with each season. Understanding the colonization and infection potential of upper respiratory organisms is important, particularly for viruses. Although asymptomatic HCPs certainly harbor a number of different potentially infectious agents, future studies are needed to determine whether colonized pathogens are transmitted or initiate infection in at-risk patient populations.

Etiology and clinical characteristics of influenza-like illness in healthy adults by hospitalization status

Abstract Background Viral respiratory infections are a common cause of hospitalization for younger, otherwise-healthy populations. In this study, we describe the epidemiology of influenza-like illness in non-elderly adults within the U.S. Military Health System (MHS) by pathogen and hospitalization status. Methods The Acute Respiratory Infection Consortium (ARIC) is a prospective cohort of patients with influenza-like illness within the MHS. Participants between 18 and 65 years of age were identified in outpatient settings between 2012 and 2017, and were excluded if pregnant, if reporting chronic cardiac, respiratory, renal, or neurologic disease, or if on long-term aspirin therapy. Demographics, nasopharyngeal swabs and symptom data were collected; swabs were tested for viral pathogens using a target-enriched multiplex PCR panel (TEM-PCRTM, Diatherix LLC). Data were analyzed to compare clinical features and risks for hospitalization. Results 397 participants met inclusion criteria. 34 participants required hospitalization; 363 were outpatients. Median length of hospitalization was 2 days. A virus was identified in 58.4% of outpatients (OP) and 55.9% of inpatients (IP); coronaviruses (63/363), enteroviruses (50/363), and influenza A (73/363) predominated in OP, whereas influenza A predominated among IP (35.3%, 12/34). There were no significant differences between OP and IP in terms of age, gender, ethnicity, or tobacco use. IP were more likely to be obese (BMI ≥30, 43.3% vs. 20.5%, P = 0.004) and less likely to have received influenza vaccination (45.5% vs. 16.9%, P > 0.001). IP with influenza did not report more severe symptoms (chills, cough, sore throat, diarrhea, myalgia, or headache) on enrollment but were more likely to have fever (temperature ≥38.0⁰ C) than OP (92.9 vs. 57.1%, P = 0.014). Conclusion Influenza A is the most frequently identified cause of hospitalization among healthy, non-elderly adults with viral respiratory infection. Although age and tobacco use may be risks for viral acquisition, they do not appear to increase the risk of hospitalization in infected patients. Non-obese BMI and influenza vaccination appear protective against hospitalization, even in a relatively healthy cohort. Disclosures L. Malone, Diatherix Laboratories: Employee, Salary; E. Grigorenko, Diatherix Laboratories: Employee, Salary; D. Stalons, Diatherix Laboratories: Employee, Salary

Performance of TEM-PCR vs. Culture for Bacterial Identification in Pediatric Musculoskeletal Infections

Abstract Background Musculoskeletal infections (MSI) in children require prompt diagnosis and treatment due to risk of local tissue damage and metastatic bacterial spread. Staphylococcus aureus is the leading cause of MSI and readily grows in culture; however, receipt of antibiotics prior to culture and the frequency of fastidious organisms in young children (e.g., Kingella kingae) often leads to negative cultures and broad treatment regimens. Thus, there is a need for improved rapid diagnostics in children with MSI. In this study, we compared the detection of MSI pathogens by culture and by target-enriched multiplex PCR (TEM-PCR™) in children with MSI. Methods Synovial fluid and bone samples were collected from patients with MSI (n = 25, 0.5–18 years). Bacterial cultures and antibiotic susceptibility testing (AST) was performed by the Vanderbilt University Medical Center clinical laboratory. Additionally, samples were evaluated by TEM-PCR for detection of S. aureus [including methicillin and clindamycin resistance genes and the Panton–Valentine leukocidin (PVL) locus], K. kingae, Haemophilus influenzae, Streptococcus pyogenes, and Streptococcus pneumoniae. Results TEM-PCR detected a pathogen in 20/25 subjects (80%), compared with 17/25 (68%) by culture. S. aureus was identified in 18 subjects, one of which was identified by TEM-PCR and not by culture. TEM-PCR also identified 2 subjects with K. kingae infection; neither was identified by culture. TEM-PCR detection of methicillin resistance and clindamycin resistance was 100% concordant with AST in the clinical laboratory. Genes encoding PVL were identified in 8/18 (44%) S. aureus samples. No bacterial co-detections were identified, and no other pathogens were identified by TEM-PCR or culture. Finally, there were no subjects with positive bacterial cultures and negative TEM-PCR results. Conclusion Rapid diagnostic assays, such as TEM-PCR, may be useful adjuncts to conventional, culture-based testing for children with MSI. Advantages include rapid identification of pathogen and early detection of antibiotic resistance genes. In a single multiplex assay, TEM-PCR provided reliable identification of MSI pathogens, with the potential for informing antibiotic selection early in the disease course. Disclosures J. Wood Jr., Diatherix: Investigator, Research support; C. Sesler, Diatherix Laboratories, LLC: Employee, Salary; D. Stalons, Diatherix Laboratories: Employee, Salary; E. Grigorenko, Diatherix Laboratories: Employee, Salary; C. B. Creech, Diatherix: Grant Investigator, Grant recipient; I. Thomsen, Diatherix: Investigator, Research support

Study to Address Threats of Acute Respiratory Infections among Congregate Military Populations (ATARI)

Abstract Background More than 90% of active duty personnel receive influenza vaccinations yearly. Despite high coverage, influenza-like illnesses (ILI) remain a frequent cause of missed duty and hospitalizations, particularly in U.S. military recruits. More research is needed on the epidemiology and etiology of ILI to reduce the burden of respiratory infections in congregated military settings. Methods We conducted a prospective cohort study to assess ILI patterns among US Army recruits in a 9-week basic combat training course at Ft. Benning, GA. Demographic data, vaccination history, and information on recent illness were collected at enrollment in January 2017. Participants were divided into two platoons with staggered biweekly visit schedules. Visits occurred from reception through training, with nasal swabs and symptom surveys (all visits) and blood draws (weeks 8 and 9). Nasal specimens were used to detect clinical and colonizing pathogens using the Diatherix TEM-PCR Respiratory Panel. Results A total of 90 recruits were enrolled in the study. Twelve recruits were lost due to training attrition in the first week of the study. The participants were male and the mean age was 23 yo (SD 4.9). There were 10 (13%) cases of ILI reported among the 78 remaining participants, 6 in week 1, 3 in week 2 and 1 in week 9. The most frequently detected pathogens in the 10 symptomatic cases were coronavirus (5, 50%), rhinovirus (4, 40%), other enterovirus (3, 30%), and influenza A (2, 20%). Pathogen co-detections were common, 8 out 10 cases were associated with 2 pathogens, representing 7 unique combinations. While rhinovirus and coronavirus were most common among asymptomatic trainees, 10% had detectable influenza A. Detection of multiple pathogens was common in the first two weeks of training (50% among those who had viral detection). The study is still in progress. Conclusion Symptomatic ILI was associated with coronavirus, rhinovirus, and enterovirus, in addition to influenza in the early weeks of training. Coronavirus and rhinovirus also circulated widely among healthy recruits, along with influenza. The findings will inform ILI control strategies for congregated military trainees. Disclosures E. Grigorenko, Diatherix Laboratories: Employee, Salary.L. Malone, Diatherix Laboratories: Employee, Salary.

Comparative Evaluation of Diatherix Target Enriched Multiplex Polymerase Chain Reaction and BioFire FilmArray in the Detection of Viral and Bacterial Respiratory Pathogens

238. Comparative Evaluation of Diatherix Target Enriched Multiplex Polymerase Chain Reaction and BioFire FilmArray in the Detection of Viral and Bacterial Respiratory Pathogens Wei-Ju Chen, PhD; John Arnold, MD; Mary Fairchok, MD; Erin Hansen, BS; Leslie Malone, MS, MB(ASCP)CM; Elena Grigorenko, PhD; Donald Stalons, PhD, D (ABMM), MPH; Jacqueline Owens Milzman, MS; Michelande Ridore, MS; Christian Coles, PhD; Timothy Burgess, MD; Eugene Millar, PhD; Infectious Disease Clinical Research Program, Uniformed Services University of the Health Sciences, Bethesda, Maryland; Naval Medical Center San Diego, San Diego, California; Madigan Army Medical Center, Tacoma, Washington; Naval Health Research Center, San Diego, California; Diatherix Laboratories, LLC, Huntsville, Alabama; Children’s National Medical Center, Washington, District of Columbia

Epidemiologic, Clinical, and Virologic Characteristics of Respiratory Syncytial Virus Infection among Otherwise Healthy Adults

www.PosterPresentations.com Epidemiologic, clinical, and virologic characteristics of Respiratory Syncytial Virus infection among otherwise healthy adults Anjali Kunz, MD3, Levi Strube, MD3, Christina Schofield, MD3, Tahaniyat N. Lalani MD4,9, Patrick J. Danaher MD5, Michael Rajnik MD6, Leslie Malone MS MB(ASCP)CM8, Elena Grigorenko PhD8, Donald Stalons PhD8, Deepika Mor MS2,9, Michelande Ridore, MS2,9, Wei-Ju Chen, PhD2,9, John C. Arnold MD1, Eugene Millar, PhD2,9, Mary P. Fairchok, MD2,3,9

Etiology Unknown: Are Less Recognized Respiratory Pathogens Associated With a Milder Course of Illness?

1Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD; 2 Naval Medical Center San Diego CA; 3 Madigan Army Medical Center, Fort Lewis WA; 4 Naval Medical Center Portsmouth VA; 5 San Antonio Military Health System, San Antonio TX; 6 Walter Reed National Military Medical Center, Washington DC; 7 Naval Health Research Center, San Diego CA; 8 Diatherix Laboratories, Inc., Huntsville AL; 9 Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda MD