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result(s) for
"Benitez, Alvaro J."
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Multiplex Real-Time Reverse Transcription PCR for Influenza A Virus, Influenza B Virus, and Severe Acute Respiratory Syndrome Coronavirus 2
2021
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2019, and the outbreak rapidly evolved into the current coronavirus disease pandemic. SARS-CoV-2 is a respiratory virus that causes symptoms similar to those caused by influenza A and B viruses. On July 2, 2020, the US Food and Drug Administration granted emergency use authorization for in vitro diagnostic use of the Influenza SARS-CoV-2 Multiplex Assay. This assay detects influenza A virus at 102.0, influenza B virus at 102.2, and SARS-CoV-2 at 100.3 50% tissue culture or egg infectious dose, or as few as 5 RNA copies/reaction. The simultaneous detection and differentiation of these 3 major pathogens increases overall testing capacity, conserves resources, identifies co-infections, and enables efficient surveillance of influenza viruses and SARS-CoV-2.
Journal Article
Comprehensive bioinformatics analysis of Mycoplasma pneumoniae genomes to investigate underlying population structure and type-specific determinants
by
Wolff, Bernard J.
,
Benitez, Alvaro J.
,
Read, Timothy D.
in
Analysis
,
Bacterial Typing Techniques
,
Bayes Theorem
2017
Mycoplasma pneumoniae is a significant cause of respiratory illness worldwide. Despite a minimal and highly conserved genome, genetic diversity within the species may impact disease. We performed whole genome sequencing (WGS) analysis of 107 M. pneumoniae isolates, including 67 newly sequenced using the Pacific BioSciences RS II and/or Illumina MiSeq sequencing platforms. Comparative genomic analysis of 107 genomes revealed >3,000 single nucleotide polymorphisms (SNPs) in total, including 520 type-specific SNPs. Population structure analysis supported the existence of six distinct subgroups, three within each type. We developed a predictive model to classify an isolate based on whole genome SNPs called against the reference genome into the identified subtypes, obviating the need for genome assembly. This study is the most comprehensive WGS analysis for M. pneumoniae to date, underscoring the power of combining complementary sequencing technologies to overcome difficult-to-sequence regions and highlighting potential differential genomic signatures in M. pneumoniae.
Journal Article
Specificity and Strain-Typing Capabilities of Nanorod Array-Surface Enhanced Raman Spectroscopy for Mycoplasma pneumoniae Detection
by
Krause, Duncan C.
,
Benitez, Alvaro J.
,
Henderson, Kelley C.
in
Biosensors
,
Cell walls
,
Clinical isolates
2015
Mycoplasma pneumoniae is a cell wall-less bacterial pathogen of the human respiratory tract that accounts for > 20% of all community-acquired pneumonia (CAP). At present the most effective means for detection and strain-typing is quantitative polymerase chain reaction (qPCR), which can exhibit excellent sensitivity and specificity but requires separate tests for detection and genotyping, lacks standardization between available tests and between labs, and has limited practicality for widespread, point-of-care use. We have developed and previously described a silver nanorod array-surface enhanced Raman Spectroscopy (NA-SERS) biosensing platform capable of detecting M. pneumoniae with statistically significant specificity and sensitivity in simulated and true clinical throat swab samples, and the ability to distinguish between reference strains of the two main genotypes of M. pneumoniae. Furthermore, we have established a qualitative lower endpoint of detection for NA-SERS of < 1 genome equivalent (cell/μl) and a quantitative multivariate detection limit of 5.3 ± 1 cells/μl. Here we demonstrate using partial least squares- discriminatory analysis (PLS-DA) of sample spectra that NA-SERS correctly identified M. pneumoniae clinical isolates from globally diverse origins and distinguished these from a panel of 12 other human commensal and pathogenic mycoplasma species with 100% cross-validated statistical accuracy. Furthermore, PLS-DA correctly classified by strain type all 30 clinical isolates with 96% cross-validated accuracy for type 1 strains, 98% cross-validated accuracy for type 2 strains, and 90% cross-validated accuracy for type 2V strains.
Journal Article
Correction: Comprehensive bioinformatics analysis of Mycoplasma pneumoniae genomes to investigate underlying population structure and type-specific determinants
by
Wolff, Bernard J.
,
Benitez, Alvaro J.
,
Read, Timothy D.
in
Bioinformatics
,
Genomes
,
Population
2017
[This corrects the article DOI: 10.1371/journal.pone.0174701.].
Journal Article
Development and Implementation of Multiplex TaqMan Array Cards for Specimen Testing at Child Health and Mortality Prevention Surveillance Site Laboratories
2019
Child Health and Mortality Prevention Surveillance (CHAMPS) laboratories are employing a variety of laboratory methods to identify infectious agents contributing to deaths of children <5 years old and stillbirths in sub-Saharan Africa and South Asia. In support of this long-term objective, our team developed TaqMan Array Cards (TACs) for testing postmortem specimens (blood, cerebrospinal fluid, lung tissue, respiratory tract swabs, and rectal swabs) for >100 real-time polymerase chain reaction (PCR) targets in total (30–45 per card depending on configuration). Multipathogen panels were configured by syndrome and customized to include pathogens of significance in young children within the regions where CHAMPS is conducted, including bacteria (57 targets covering 30 genera), viruses (48 targets covering 40 viruses), parasites (8 targets covering 8 organisms), and fungi (3 targets covering 3 organisms). The development and application of multiplex real-time PCR reactions to the TAC microfluidic platform increased the number of targets in each panel while maintaining assay efficiency and replicates for heightened sensitivity. These advances represent a substantial improvement in the utility of this technology for infectious disease diagnostics and surveillance. We optimized all aspects of the CHAMPS molecular laboratory testing workflow including nucleic acid extraction, quality assurance, and data management to ensure comprehensive molecular testing of specimens and high-quality data. Here we describe the development and implementation of multiplex TACs and associated laboratory protocols for specimen processing, testing, and data management at CHAMPS site laboratories.
Journal Article
Mycoplasma hominis Infections Transmitted Through Amniotic Tissue Product
by
Halpin, Alison Laufer
,
Winchell, Jonas M.
,
Ratliff, Amy E.
in
ARTICLES AND COMMENTARIES
,
Bacteria
,
Bone surgery
2017
Background. Mycoplasma hominis is a commensal genitourinary tract organism that can cause infections outside the genitourinary tract. We investigated a cluster of M. hominis surgical site infections in patients who underwent spine surgery, all associated with amniotic tissue linked to a common donor. Methods. Laboratory tests of tissue product from the donor, including culture, quantitative real-time polymerase chain reaction (qPCR), and whole-genome sequencing were performed. Use of this amniotic tissue product was reviewed. A multistate investigation to identify additional cases and locate any unused products was conducted. Results. Twenty-seven tissue product vials from a donor were distributed to facilities in 7 states; at least 20 vials from this donor were used in 14 patients. Of these, 4 of 14 (29%) developed surgical site infections, including 2 M. hominis infections. Mycoplasma hominis was detected by culture and qPCR in 2 unused vials from the donor. Sequencing indicated >99% similarity between patient and unopened vial isolates. For 5 of 27 (19%) vials, the final disposition could not be confirmed. Conclusions. Mycoplasma hominis was transmitted through amniotic tissue from a single donor to 2 recipients. Current routine donor screening and product testing does not detect all potential pathogens. Clinicians should be aware that M. hominis can cause surgical site infections, and may not be detected by routine clinical cultures. The lack of a standardized system to track tissue products in healthcare facilities limits the ability of public health agencies to respond to outbreaks and investigate other adverse events associated with these products.
Journal Article
Molecular Detection and Characterization of Mycoplasma pneumoniae Among Patients Hospitalized With Community-Acquired Pneumonia in the United States
2015
We report molecular characteristics of M. pneumoniae in respiratory specimens from children and adults hospitalized with CAP. The P1 type 1 genotype and MLVA type 4/5/7/2 predominated, but proportions of types differed between children and adults. Macrolide resistance was rare.Abstract
Background.
Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP). The molecular characteristics of M pneumoniae detected in patients hospitalized with CAP in the United States are poorly described.
Methods.
We performed molecular characterization of M pneumoniae in nasopharyngeal/oropharyngeal swabs from children and adults hospitalized with CAP in the Centers for Disease Control and Prevention Etiology of Pneumonia in the Community (EPIC) study, including P1 typing, multilocus variable-number tandem-repeat analysis (MLVA), and macrolide susceptibility genotyping.
Results.
Of 216 M pneumoniae polymerase chain reaction-positive specimens, 40 (18.5%) were obtained from adults and 176 (81.5%) from children. P1 type distribution differed between adults (64% type 1 and 36% type 2) and children (84% type 1, 13% type 2, and 3% variant) (P < .05) and among sites (P < .01). Significant differences in the proportions of MLVA types 4/5/7/2 and 3/5/6/2 were also observed by age group (P < .01) and site (P < .01). A macrolide-resistant genotype was ide.jpegied in 7 (3.5%) specimens, 5 of which were from patients who had recently received macrolide therapy. No significant differences in clinical characteristics were ide.jpegied among patients with various strain types or between macrolide-resistant and -sensitive M pneumoniae infections.
Conclusions.
The P1 type 1 genotype and MLVA type 4/5/7/2 predominated, but there were differences between children and adults and among sites. Macrolide resistance was rare. Differences in strain types did not appear to be associated with differences in clinical outcomes. Whole genome sequencing of M pneumoniae may help ide.jpegy better ways to characterize strains.
Journal Article
Use of Real-Time PCR for Chlamydia psittaci Detection in Human Specimens During an Outbreak of Psittacosis — Georgia and Virginia, 2018
2021
Psittacosis is typically a mild febrile respiratory illness caused by infection with the bacterium Chlamydia psittaci and usually transmitted to humans by infected birds (1). On average, 11 psittacosis cases per year were reported in the United States during 2000-2017. During August-October 2018, the largest U.S. psittacosis outbreak in 30 years (82 cases identified*) occurred in two poultry slaughter plants, one each in Virginia and Georgia, that shared source farms (2). CDC used C. psittaci real-time polymerase chain reaction (PCR) to test 54 human specimens from this outbreak. This was the largest number of human specimens from a single outbreak ever tested for C. psittaci using real-time PCR, which is faster and more sensitive than commercially available serologic tests. This represented a rare opportunity to assess the utility of multiple specimen types for real-time PCR detection of C. psittaci. C. psittaci was detected more frequently in lower respiratory specimens (59% [10 of 17]) and stool (four of five) than in upper respiratory specimens (7% [two of 28]). Among six patients with sputum and nasopharyngeal swabs tested, C. psittaci was detected only in sputum in five patients. Cycle threshold (Ct) values suggested bacterial load was higher in lower respiratory specimens than in nasopharyngeal swabs. These findings support prioritizing lower respiratory specimens for real-time PCR detection of C. psittaci. Stool specimens might also have utility for diagnosis of psittacosis.
Journal Article
Identification of Bacterial and Viral Codetections With Mycoplasma pneumoniae Using the TaqMan Array Card in Patients Hospitalized With Community-Acquired Pneumonia
2016
Mycoplasma pneumoniae was detected in a number of patients with community-acquired pneumonia in a recent prospective study. To assess whether other pathogens were also detected in these patients, TaqMan Array Cards were used to test 216 M pneumoniae-positive respiratory specimens for 25 additional viral and bacterial respiratory pathogens. It is interesting to note that 1 or more codetections, predominantly bacterial, were identified in approximately 60% of specimens, with codetections being more common in children.
Journal Article
Complete Genome Sequence of Mycoplasma pneumoniae Type 2 Reference Strain FH Using Single-Molecule Real-Time Sequencing Technology
2017
ABSTRACT Mycoplasma pneumoniae type 2 strain FH was previously sequenced with Illumina (FH-Illumina) and 454 (FH-454) technologies according to Xiao et al. (2015) and Krishnakumar et al. (2010). Comparative analyses revealed differences in genomic content between these sequences, including a 6-kb region absent from the FH-454 submission. Here, we present a complete genome sequence of FH sequenced with the Pacific Biosciences RSII platform.
Journal Article