Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-30 (of 85 Records) |
Query Trace: Winchell JM[original query] |
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Expanded geographic distribution for two Legionella pneumophila sequence types of clinical concern
Hamlin JAP , Kozak-Muiznieks NA , Mercante JW , Rishishwar L , Norris ET , Gaines AB , Ishaq MK , Winchell JM , Willby MJ . mSphere 2024 e0075623 Legionella pneumophila serogroup 1 sequence types (ST) 213 and 222, a single-locus variant of ST213, were first detected in the early 1990s in the Midwest United States (U.S.) and the late 1990s in the Northeast U.S. and Canada. Since 1992, these STs have increasingly been implicated in community-acquired sporadic and outbreak-associated Legionnaires' disease (LD) cases. We were interested in understanding the change in LD frequency due to these STs and identifying genetic features that differentiate these STs from one another. For the geographic area examined here (Mountain West to Northeast) and over the study period (1992-2020), ST213/222-associated LD cases identified by the Centers for Disease Control and Prevention increased by 0.15 cases per year, with ST213/222-associated LD cases concentrated in four states: Michigan (26%), New York (18%), Minnesota (16%), and Ohio (10%). Additionally, between 2002 and 2021, ST222 caused at least five LD outbreaks in the U.S.; no known outbreaks due to ST213 occurred in the U.S. during this time. We compared the genomes of 230 ST213/222 isolates and found that the mean of the average nucleotide identity (ANI) within each ST was high (99.92% for ST222 and 99.92% for ST213), with a minimum between ST ANI of 99.50% and a maximum of 99.87%, indicating low genetic diversity within and between these STs. While genomic features were identified (e.g., plasmids and CRISPR-Cas systems), no association explained the increasing geographic distribution and prevalence of ST213 and ST222. Yet, we provide evidence of the expanded geographical distribution of ST213 and ST222 in the U.S.IMPORTANCESince the 1990s, cases of Legionnaires' disease (LD) attributed to a pair of closely related Legionella pneumophila variants, ST213 and ST222, have increased in the U.S. Furthermore, between 2002 and 2021, ST222 caused at least five outbreaks of LD in the U.S., while ST213 has not been linked to any U.S. outbreak. We wanted to understand how the rate of LD cases attributed to these variants has changed over time and compare the genetic features of the two variants. Between 1992 and 2020, we determined an increase of 0.15 LD cases ascribed to ST213/222 per year in the geographic region studied. Our research shows that these STs are spreading within the U.S., yet most of the cases occurred in four states: Michigan, New York, Minnesota, and Ohio. Additionally, we found little genetic diversity within and between these STs nor could specific genetic features explain their geographic spread. |
Genomic analysis of Chlamydia psittaci from a multistate zoonotic outbreak in two chicken processing plants
Wolff BJ , Waller JL , Benitez AJ , Gaines A , Conley AB , Rishishwar L , Chande AT , Morrison SS , Jordan IK , Diaz MH , Winchell JM . J Genomics 2023 11 40-44 Four Chlamydia psittaci isolates were recovered from clinical specimens from ill workers during a multistate outbreak at two chicken processing plants. Whole genome sequencing analyses revealed high similarity to C. psittaci genotype D. The isolates differed from each other by only two single nucleotide polymorphisms, indicating a common source. |
Multiplex Real-time PCR Assay for the Detection of all Chlamydia Species and Simultaneous Differentiation of C. psittaci and C. pneumoniae in Human Clinical Specimens.
Wolff BJ , Gaines A , Conley AB , Norris E , Rishishwar L , Chande AT , Yang E , Diaz MH , Winchell JM . Ann Lab Med 2023 43 (4) 375-380 We developed and assessed the performance of a new multiplex real-time PCR assay for the detection of all Chlamydia species and simultaneous differentiation of Chlamydia psittaci and Chlamydia pneumoniae-two important human respiratory pathogens-in human clinical specimens. Next-generation sequencing was used to identify unique targets to design real-time PCR assays targeting all Chlamydia species, C. psittaci, and C. pneumoniae. To validate the assay, we used a panel of 49 culture isolates comprising seven C. psittaci genotypes, eight C. pneumoniae isolates, seven other Chlamydia species, and 22 near-neighbor bacterial and viral isolates, along with 22 specimens from external quality assessment (EQA) panels and 34 nasopharyngeal and oropharyngeal swabs and cerebrospinal fluid, stool, and sputum specimens previously identified as positive or negative for C. psittaci or C. pneumoniae. The assays were 100% specific, with limits of detection of 7.64- 9.02 fg/μL. The assay results matched with historical assay results for all specimens, except for one owing to the increased sensitivity of the new C. psittaci assay; the results of the EQA specimens were 100% accurate. This assay may improve the timely and accurate clinical diagnosis of Chlamydia infections and provide a greater understanding of the burden of disease caused by these agents. |
Risk factors for community-acquired bacterial infection among young infants in South Asia: a longitudinal cohort study with nested case-control analysis
Connor NE , Islam MS , Mullany LC , Shang N , Bhutta ZA , Zaidi AKM , Soofi S , Nisar I , Panigrahi P , Panigrahi K , Satpathy R , Bose A , Isaac R , Baqui AH , Mitra DK , Sadeq-Ur Rahman Q , Hossain T , Schrag SJ , Winchell JM , Arvay ML , Diaz MH , Waller JL , Weber MW , Hamer DH , Hibberd P , Nawshad Uddin Ahmed ASM , Islam M , Hossain MB , Qazi SA , El Arifeen S , Darmstadt GL , Saha SK . BMJ Glob Health 2022 7 (11) OBJECTIVE: Risk factors predisposing infants to community-acquired bacterial infections during the first 2 months of life are poorly understood in South Asia. Identifying risk factors for infection could lead to improved preventive measures and antibiotic stewardship. METHODS: Five sites in Bangladesh, India and Pakistan enrolled mother-child pairs via population-based pregnancy surveillance by community health workers. Medical, sociodemographic and epidemiological risk factor data were collected. Young infants aged 0-59 days with signs of possible serious bacterial infection (pSBI) and age-matched controls provided blood and respiratory specimens that were analysed by blood culture and real-time PCR. These tests were used to build a Bayesian partial latent class model (PLCM) capable of attributing the probable cause of each infant's infection in the ANISA study. The collected risk factors from all mother-child pairs were classified and analysed against the PLCM using bivariate and stepwise logistic multivariable regression modelling to determine risk factors of probable bacterial infection. RESULTS: Among 63 114 infants born, 14 655 were assessed and 6022 had signs of pSBI; of these, 81% (4859) provided blood samples for culture, 71% (4216) provided blood samples for quantitative PCR (qPCR) and 86% (5209) provided respiratory qPCR samples. Risk factors associated with bacterial-attributed infections included: low (relative risk (RR) 1.73, 95% credible interval (CrI) 1.42 to 2.11) and very low birth weight (RR 5.77, 95% CrI 3.73 to 8.94), male sex (RR 1.27, 95% CrI 1.07 to 1.52), breathing problems at birth (RR 2.50, 95% CrI 1.96 to 3.18), premature rupture of membranes (PROMs) (RR 1.27, 95% CrI 1.03 to 1.58) and being in the lowest three socioeconomic status quintiles (first RR 1.52, 95% CrI 1.07 to 2.16; second RR 1.41, 95% CrI 1.00 to 1.97; third RR 1.42, 95% CrI 1.01 to 1.99). CONCLUSION: Distinct risk factors: birth weight, male sex, breathing problems at birth and PROM were significantly associated with the development of bacterial sepsis across South Asian community settings, supporting refined clinical discernment and targeted use of antimicrobials. |
Histopathology Is Key to Interpreting Multiplex Molecular Test Results From Postmortem Minimally Invasive Tissue Samples
Ritter JM , Seixas JN , Walong E , Dawa J , Onyango C , Pimenta FC , da Gloria Carvalho M , Silva-Flannery L , Jenkinson T , Howard K , Bhatnagar J , Diaz M , Winchell JM , Zaki SR , Chaves SS , Martines RB . Clin Infect Dis 2021 73 S351-s359 BACKGROUND: Minimally invasive tissue sampling (MITS) is an alternative to complete autopsy for determining causes of death. Multiplex molecular testing performed on MITS specimens poses challenges of interpretation, due to high sensitivity and indiscriminate detection of pathogenic, commensal, or contaminating microorganisms. METHODS: MITS was performed on 20 deceased children with respiratory illness, at 10 timepoints up to 88 hours postmortem. Samples were evaluated by multiplex molecular testing on fresh tissues by TaqMan® Array Card (TAC) and by histopathology, special stains, immunohistochemistry (IHC), and molecular testing (PCR) on formalin-fixed, paraffin-embedded (FFPE) tissues. Results were correlated to determine overall pathologic and etiologic diagnoses and to guide interpretation of TAC results. RESULTS: MITS specimens collected up to 3 days postmortem were adequate for histopathologic evaluation and testing. Seven different etiologic agents were detected by TAC in 10 cases. Three cases had etiologic agents detected by FFPE or other methods and not TAC; 2 were agents not present on TAC, and 2 were streptococci that may have been species other than those present on TAC. Result agreement was 43% for TAC and IHC or PCR, and 69% for IHC and PCR. Extraneous TAC results were common, especially when aspiration was present. CONCLUSIONS: TAC can be performed on MITS up to 3 days after death with refrigeration and provides a sensitive method for detection of pathogens but requires careful interpretation in the context of clinicoepidemiologic and histopathologic findings. Interpretation of all diagnostic tests in aggregate to establish overall case diagnoses maximizes the utility of TAC in MITS. |
Effect of Time Since Death on Multipathogen Molecular Test Results of Postmortem Specimens Collected Using Minimally Invasive Tissue Sampling Techniques.
Dawa J , Walong E , Onyango C , Mathaiya J , Muturi P , Bunei M , Ochieng W , Barake W , Seixas JN , Mayieka L , Ochieng M , Omballa V , Lidechi S , Hunsperger E , Otieno NA , Ritter JM , Widdowson MA , Diaz MH , Winchell JM , Martines RB , Zaki SR , Chaves SS . Clin Infect Dis 2021 73 S360-s367 BACKGROUND: We used postmortem minimally invasive tissue sampling (MITS) to assess the effect of time since death on molecular detection of pathogens among respiratory illness-associated deaths. METHODS: Samples were collected from 20 deceased children (aged 1-59 months) hospitalized with respiratory illness from May 2018 through February 2019. Serial lung and/or liver and blood samples were collected using MITS starting soon after death and every 6 hours thereafter for up to 72 hours. Bodies were stored in the mortuary refrigerator for the duration of the study. All specimens were analyzed using customized multipathogen TaqMan® array cards (TACs). RESULTS: We identified a median of 3 pathogens in each child's lung tissue (range, 1-8; n = 20), 3 pathogens in each child's liver tissue (range, 1-4; n = 5), and 2 pathogens in each child's blood specimen (range, 0-4; n = 5). Pathogens were not consistently detected across all collection time points; there was no association between postmortem interval and the number of pathogens detected (P = .43) and no change in TAC cycle threshold value over time for pathogens detected in lung tissue. Human ribonucleoprotein values indicated that specimens collected were suitable for testing throughout the study period. CONCLUSIONS: Results suggest that lung, liver, and blood specimens can be collected using MITS procedures up to 4 days after death in adequately preserved bodies. However, inconsistent pathogen detection in samples needs careful consideration before drawing definitive conclusions on the etiologic causes of death. |
Multiplex Real-Time Reverse Transcription PCR for Influenza A Virus, Influenza B Virus, and Severe Acute Respiratory Syndrome Coronavirus 2.
Shu B , Kirby MK , Davis WG , Warnes C , Liddell J , Liu J , Wu KH , Hassell N , Benitez AJ , Wilson MM , Keller MW , Rambo-Martin BL , Camara Y , Winter J , Kondor RJ , Zhou B , Spies S , Rose LE , Winchell JM , Limbago BM , Wentworth DE , Barnes JR . Emerg Infect Dis 2021 27 (7) 1821-1830 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 10(2.0), influenza B virus at 10(2.2), and SARS-CoV-2 at 10(0.3) 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. |
Use of Real-Time PCR for Chlamydia psittaci Detection in Human Specimens During an Outbreak of Psittacosis - Georgia and Virginia, 2018.
McGovern OL , Kobayashi M , Shaw KA , Szablewski C , Gabel J , Holsinger C , Drenzek C , Brennan S , Milucky J , Farrar JL , Wolff BJ , Benitez AJ , Thurman KA , Diaz MH , Winchell JM , Schrag S . MMWR Morb Mortal Wkly Rep 2021 70 (14) 505-509 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. |
Causes of fever in primary care in Southeast Asia and the performance of C-reactive protein in discriminating bacterial from viral pathogens
Althaus T , Thaipadungpanit J , Greer RC , Swe MMM , Dittrich S , Peerawaranun P , Smit PW , Wangrangsimakul T , Blacksell S , Winchell JM , Diaz MH , Day NPJ , Smithuis F , Turner P , Lubell Y . Int J Infect Dis 2020 96 334-342 OBJECTIVES: We investigated causes of fever in the primary levels of care in Southeast Asia, and evaluated whether C-reactive protein (CRP) could distinguish bacterial from viral pathogens. METHODS: Blood and nasopharyngeal swab specimens were taken from children and adults with fever (>37.5 C) or history of fever (<14 days) in Thailand and Myanmar. RESULTS: Of 773 patients with at least one blood or nasopharyngeal swab specimen collected, 227 (29.4%) had a target organism detected. Influenza virus type A was detected in 85/227 cases (37.5%), followed by dengue virus (30 cases, 13.2%), respiratory syncytial virus (24 cases, 10.6%) and Leptospira spp. (9 cases, 4.0%). Clinical outcome was similar between patients with a bacterial or a viral organism, regardless of antibiotic prescription. CRP was higher among patients with a bacterial organism compared to those with a viral organism (median 18mg/L, interquartile range [10-49] versus 10mg/L [</=8-22], p-value 0.003), with an area under the curve of 0.65, 95% confidence interval (0.55-0.75). CONCLUSIONS: Serious bacterial infections requiring antibiotics are exceptions rather than the rule in the first lines of care. CRP-testing could assist in ruling out such cases in settings where diagnostic uncertainty is high and routine antibiotic prescription is common. The original CRP randomised-controlled trial (RCT) was registered with ClinicalTrials.gov, number NCT02758821. |
Evaluation of Commercial Molecular Diagnostic Methods for the Detection and Determination of Macrolide Resistance in Mycoplasma pneumoniae .
Leal SMJr , Totten AH , Xiao L , Crabb DM , Ratliff A , Duffy LB , Fowler KB , Mixon E , Winchell JM , Diaz MH , Benitez AJ , Wolff BJ , Qin X , Tang YW , Gonzalez M , Selvarangan R , Hong T , Brooks E , Dallas S , Atkinson TP , Zheng X , Dien Bard J , Waites KB . J Clin Microbiol 2020 58 (6) We evaluated six commercial molecular tests targeting M. pneumoniae: the BioFire FilmArray Respiratory Panel (RP), the Meridian Alethia Mycoplasma Direct, the GenMark ePlex Respiratory Pathogen Panel (RPP), the Luminex NxTAG RPP, the ELITech ELITe InGenius Mycoplasma MGB Research Use Only Polymerase Chain Reaction (PCR), and the SpeeDx Resistance Plus MP. Laboratory-developed PCR assays at the University of Alabama at Birmingham and the Centers for Disease Control and Prevention were used as reference standards. Among 428 specimens, 212 were designated confirmed-positives for M. pneumoniae The highest clinical sensitivities were found with the InGenius (99.5%) and the FilmArray RP (98.1%). The Resistance Plus MP identified 93.3% of the confirmed-positive specimens, whereas 83.6%, 64.6%, and 55.7% were identified by the ePlex RPP, NxTAG RPP, and Mycoplasma Direct assays, respectively. There was no significant difference between the sensitivity of the reference methods and that of the FilmArray RP and InGenius assays, but the remaining four assays detected significantly fewer positive specimens (p < 0.05). Specificities of all assays were 99.5 - 100%. The Resistance Plus MP detected macrolide resistance in 27/33 specimens resulting in a sensitivity of 81.8%. This study provides the first large scale comparison of commercial molecular assays for detection of M. pneumoniae in the United States and identified clear differences among their performance. Additional studies are necessary to explore the impact of variable test performance on patient outcome. |
Development and Implementation of Multiplex TaqMan Array Cards for Specimen Testing at Child Health and Mortality Prevention Surveillance Site Laboratories.
Diaz MH , Waller JL , Theodore MJ , Patel N , Wolff BJ , Benitez AJ , Morris T , Raghunathan PL , Breiman RF , Whitney CG , Blau DM , Winchell JM . Clin Infect Dis 2019 69 S311-s321 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. |
Comparison of respiratory pathogen yields from Nasopharyngeal/Oropharyngeal swabs and sputum specimens collected from hospitalized adults in rural Western Kenya
Nyawanda BO , Njuguna HN , Onyango CO , Makokha C , Lidechi S , Fields B , Winchell JM , Katieno JS , Nyaundi J , Ade F , Emukule GO , Mott JA , Otieno N , Widdowson MA , Chaves SS . Sci Rep 2019 9 (1) 11237 Molecular diagnostic methods are becoming increasingly available for assessment of acute lower respiratory illnesses (ALRI). However, nasopharyngeal/oropharyngeal (NP/OP) swabs may not accurately reflect etiologic agents from the lower respiratory tract where sputum specimens are considered as a more representative sample. The pathogen yields from NP/OP against sputum specimens have not been extensively explored, especially in tropical countries. We compared pathogen yields from NP/OP swabs and sputum specimens from patients ≥18 years hospitalized with ALRI in rural Western Kenya. Specimens were tested for 30 pathogens using TaqMan Array Cards (TAC) and results compared using McNemar’s test. The agreement for pathogen detection between NP/OP and sputum specimens ranged between 85–100%. More viruses were detected from NP/OP specimens whereas Klebsiella pneumoniae and Mycobacterium tuberculosis were more common in sputum specimens. There was no clear advantage in using sputum over NP/OP specimens to detect pathogens of ALRI in adults using TAC in the context of this tropical setting. |
Assessment of eight nucleic acid amplification technologies for potential use to detect infectious agents in low-resource settings
Cantera JL , White H , Diaz MH , Beall SG , Winchell JM , Lillis L , Kalnoky M , Gallarda J , Boyle DS . PLoS One 2019 14 (4) e0215756 Nucleic acid amplification technologies (NAATs) are high-performance tools for rapidly and accurately detecting infectious agents. They are widely used in high-income countries to diagnose disease and improve patient care. The complexities associated with test methods, reagents, equipment, quality control and assurance require dedicated laboratories with trained staff, which can exclude their use in low-resource and decentralized healthcare settings. For certain diseases, fully integrated NAAT devices and assays are available for use in environmentally-controlled clinics or emergency rooms where relatively untrained staff can perform testing. However, decentralized settings in many low- and middle-income countries with large burdens of infectious disease are challenged by extreme environments, poor infrastructure, few trained staff and limited financial resources. Therefore, there is an urgent need for low-cost, integrated NAAT tools specifically designed for use in low-resource settings (LRS). Two essential components of integrated NAAT tools are: 1) efficient nucleic acid extraction technologies for diverse and complex sample types; and 2) robust and sensitive nucleic acid amplification and detection technologies. In prior work we reported the performance and workflow capacity for the nucleic acid extraction component. In the current study we evaluated performance of eight novel nucleic acid amplification and detection technologies from seven developers using blinded panels of RNA and/or DNA from three pathogens to assess both diagnostic accuracy and suitability as an essential component for low-cost NAAT in LRS. In this exercise, we noted significant differences in performance among these technologies and identified those most promising for potential further development. |
Surveillance for incidence and etiology of early-onset neonatal sepsis in Soweto, South Africa.
Velaphi SC , Westercamp M , Moleleki M , Pondo T , Dangor Z , Wolter N , von Gottberg A , Shang N , Demirjian A , Winchell JM , Diaz MH , Nakwa F , Okudo G , Wadula J , Cutland C , Schrag SJ , Madhi SA . PLoS One 2019 14 (4) e0214077 BACKGROUND: Globally, over 400,000 neonatal deaths in 2015 were attributed to sepsis, however, the incidence and etiologies of these infections are largely unknown in low-middle income countries. We aimed to determine incidence and etiology of community-acquired early-onset (<72 hours age) sepsis (EOS) using culture and molecular diagnostics. METHODS: This was a prospective observational study, in which we conducted a surveillance for pathogens using a combination of blood culture and a polymerase chain reaction (PCR)-based test. Blood culture was performed on all neonates with suspected EOS. Among the subset fulfilling criteria for protocol-defined EOS, blood and nasopharyngeal (NP) respiratory swabs were tested by quantitative real-time reverse-transcriptase PCR using a Taqman Array Card (TAC) with 15 bacterial and 12 viral targets. Blood and NP samples from 312 healthy newborns were also tested by TAC to estimate background positivity rates. We used variant latent-class methods to attribute etiologies and calculate pathogen-specific proportions and incidence rates. RESULTS: We enrolled 2,624 neonates with suspected EOS and from these 1,231 newborns met criteria for protocol-defined EOS (incidence- 39.3/1,000 live-births). Using the partially latent-class modelling, only 26.7% cases with protocol-defined EOS had attributable etiology, and the largest pathogen proportion were Ureaplasma spp. (5.4%; 95%CI: 3.6-8.0) and group B Streptococcus (GBS) (4.8%; 95%CI: 4.1-5.8), and no etiology was attributable for 73.3% of cases. Blood cultures were positive in 99/1,231 (8.0%) with protocol-defined EOS (incidence- 3.2/1,000 live-births). Leading pathogens on blood culture included GBS (35%) and viridans streptococci (24%). Ureaplasma spp. was the most common organism identified on TAC among cases with protocol-defined EOS. CONCLUSION: Using a combination of blood culture and a PCR-based test the common pathogens isolated in neonates with sepsis were Ureaplasma spp. and GBS. Despite documenting higher rates of protocol-defined EOS and using a combination of tests, the etiology for EOS remains elusive. |
Culture of Clinical Specimens Reveals Extensive Diversity of Legionella pneumophila Strains in Arizona.
Raphael BH , Huynh T , Brown E , Smith JC , Ruberto I , Getsinger L , White S , Winchell JM . mSphere 2019 4 (1) Between 2000 and 2017, a total of 236 Legionella species isolates from Arizona were submitted to the CDC for reference testing. Most of these isolates were recovered from bronchoalveolar lavage specimens. Although the incidence of legionellosis in Arizona is less than the overall U.S. incidence, Arizona submits the largest number of isolates to the CDC for testing compared to those from other states. In addition to a higher proportion of culture confirmation of legionellosis cases in Arizona than in other states, all Legionella pneumophila isolates are forwarded to the CDC for confirmatory testing. Compared to that from other states, a higher proportion of isolates from Arizona were identified as belonging to L. pneumophila serogroups 6 (28.2%) and 8 (8.9%). Genome sequencing was conducted on 113 L. pneumophila clinical isolates not known to be associated with outbreaks in order to understand the genomic diversity of strains causing legionellosis in Arizona. Whole-genome multilocus sequence typing (wgMLST) revealed 17 clusters of isolates sharing at least 99% identical allele content. Only two of these clusters contained isolates from more than one individual with exposure at the same facility. Additionally, wgMLST analysis revealed a group of 31 isolates predominantly belonging to serogroup 6 and containing isolates from three separate clusters. Single nucleotide polymorphism (SNP) and pangenome analysis were used to further resolve genome sequences belonging to a subset of isolates. This study demonstrates that culture of clinical specimens for Legionella spp. reveals a highly diverse population of strains causing legionellosis in Arizona which could be underappreciated using other diagnostic approaches.IMPORTANCE Culture of clinical specimens from patients with Legionnaires' disease is rarely performed, restricting our understanding of the diversity and ecology of Legionella Culture of Legionella from patient specimens in Arizona revealed a greater proportion of non-serogroup 1 Legionella pneumophila isolates than in other U.S. isolates examined. Disease caused by such isolates may go undetected using other diagnostic methods. Moreover, genome sequence analysis revealed that these isolates were genetically diverse, and understanding these populations may help in future environmental source attribution studies. |
Performance and workflow assessment of six nucleic acid extraction technologies for use in resource limited settings
Beall SG , Cantera J , Diaz MH , Winchell JM , Lillis L , White H , Kalnoky M , Gallarda J , Boyle DS . PLoS One 2019 14 (4) e0215753 Infectious disease nucleic acid amplification technologies (NAAT) have superior sensitivity, specificity, and rapid time to result compared to traditional microbiological methods. Recovery of concentrated, high quality pathogen nucleic acid (NA) from complex specimen matrices is required for optimal performance of several NA amplification/detection technologies such as polymerase chain reaction (PCR). Fully integrated NAAT platforms that enable rapid sample-to-result workflows with minimal user input are generally restricted to larger reference lab settings, and their complexity and cost are prohibitive to widespread implementation in resource limited settings (RLS). Identification of component technologies for incorporation of reliable and affordable sample preparation with pathogen NA amplification/detection into an integrated platform suitable for RLS, is a necessary first step toward achieving the overarching goal of reducing infectious disease-associated morbidity and mortality globally. In the current study, we evaluate the performance of six novel NA extraction technologies from different developers using blinded panels of stool, sputum and blood spiked with variable amounts of quality-controlled DNA- and/or RNA-based microbes. The extraction efficiencies were semi-quantitatively assessed using validated real-time reverse transcription (RT)-PCR assays specific for each microbe and comparing target-specific RT-PCR results to those obtained with reference NA extraction methods. The technologies were ranked based on overall diagnostic accuracy (analytical sensitivity and specificity). Sample input and output volumes, total processing time, user-required manual steps and cost estimates were also examined for suitability in RLS. Together with the performance analysis, these metrics were used to select the more suitable candidate technologies for further optimization of integrated NA amplification and detection technologies for RLS. |
Genomic heterogeneity differentiates clinical and environmental subgroups of Legionella pneumophila sequence type 1.
Mercante JW , Caravas JA , Ishaq MK , Kozak-Muiznieks NA , Raphael BH , Winchell JM . PLoS One 2018 13 (10) e0206110 Legionella spp. are the cause of a severe bacterial pneumonia known as Legionnaires' disease (LD). In some cases, current genetic subtyping methods cannot resolve LD outbreaks caused by common, potentially endemic L. pneumophila (Lp) sequence types (ST), which complicates laboratory investigations and environmental source attribution. In the United States (US), ST1 is the most prevalent clinical and environmental Lp sequence type. In order to characterize the ST1 population, we sequenced 289 outbreak and non-outbreak associated clinical and environmental ST1 and ST1-variant Lp strains from the US and, together with international isolate sequences, explored their genetic and geographic diversity. The ST1 population was highly conserved at the nucleotide level; 98% of core nucleotide positions were invariant and environmental isolates unassociated with human disease (n = 99) contained ~65% more nucleotide diversity compared to clinical-sporadic (n = 139) or outbreak-associated (n = 28) ST1 subgroups. The accessory pangenome of environmental isolates was also ~30-60% larger than other subgroups and was enriched for transposition and conjugative transfer-associated elements. Up to ~10% of US ST1 genetic variation could be explained by geographic origin, but considerable genetic conservation existed among strains isolated from geographically distant states and from different decades. These findings provide new insight into the ST1 population structure and establish a foundation for interpreting genetic relationships among ST1 strains; these data may also inform future analyses for improved outbreak investigations. |
Causes and incidence of community-acquired serious infections among young children in south Asia (ANISA): an observational cohort study
Saha SK , Schrag SJ , El Arifeen S , Mullany LC , Shahidul Islam M , Shang N , Qazi SA , Zaidi AKM , Bhutta ZA , Bose A , Panigrahi P , Soofi SB , Connor NE , Mitra DK , Isaac R , Winchell JM , Arvay ML , Islam M , Shafiq Y , Nisar I , Baloch B , Kabir F , Ali M , Diaz MH , Satpathy R , Nanda P , Padhi BK , Parida S , Hotwani A , Hasanuzzaman M , Ahmed S , Belal Hossain M , Ariff S , Ahmed I , Ibne Moin SM , Mahmud A , Waller JL , Rafiqullah I , Quaiyum MA , Begum N , Balaji V , Halen J , Nawshad Uddin Ahmed ASM , Weber MW , Hamer DH , Hibberd PL , Sadeq-Ur Rahman Q , Mogan VR , Hossain T , McGee L , Anandan S , Liu A , Panigrahi K , Abraham AM , Baqui AH . Lancet 2018 392 (10142) 145-159 BACKGROUND: More than 500 000 neonatal deaths per year result from possible serious bacterial infections (pSBIs), but the causes are largely unknown. We investigated the incidence of community-acquired infections caused by specific organisms among neonates in south Asia. METHODS: From 2011 to 2014, we identified babies through population-based pregnancy surveillance at five sites in Bangladesh, India, and Pakistan. Babies were visited at home by community health workers up to ten times from age 0 to 59 days. Illness meeting the WHO definition of pSBI and randomly selected healthy babies were referred to study physicians. The primary objective was to estimate proportions of specific infectious causes by blood culture and Custom TaqMan Array Cards molecular assay (Thermo Fisher, Bartlesville, OK, USA) of blood and respiratory samples. FINDINGS: 6022 pSBI episodes were identified among 63 114 babies (95.4 per 1000 livebirths). Causes were attributed in 28% of episodes (16% bacterial and 12% viral). Mean incidence of bacterial infections was 13.2 (95% credible interval [CrI] 11.2-15.6) per 1000 livebirths and of viral infections was 10.1 (9.4-11.6) per 1000 livebirths. The leading pathogen was respiratory syncytial virus (5.4, 95% CrI 4.8-6.3 episodes per 1000 livebirths), followed by Ureaplasma spp (2.4, 1.6-3.2 episodes per 1000 livebirths). Among babies who died, causes were attributed to 46% of pSBI episodes, among which 92% were bacterial. 85 (83%) of 102 blood culture isolates were susceptible to penicillin, ampicillin, gentamicin, or a combination of these drugs. INTERPRETATION: Non-attribution of a cause in a high proportion of patients suggests that a substantial proportion of pSBI episodes might not have been due to infection. The predominance of bacterial causes among babies who died, however, indicates that appropriate prevention measures and management could substantially affect neonatal mortality. Susceptibility of bacterial isolates to first-line antibiotics emphasises the need for prudent and limited use of newer-generation antibiotics. Furthermore, the predominance of atypical bacteria we found and high incidence of respiratory syncytial virus indicated that changes in management strategies for treatment and prevention are needed. Given the burden of disease, prevention of respiratory syncytial virus would have a notable effect on the overall health system and achievement of Sustainable Development Goal. FUNDING: Bill & Melinda Gates Foundation. |
Mycoplasma pneumoniae among children hospitalized with community-acquired pneumonia
Kutty PK , Jain S , Taylor TH , Bramley AM , Diaz MH , Ampofo K , Arnold SR , Williams DJ , Edwards KM , McCullers JA , Pavia AT , Winchell JM , Schrag SJ , Hicks LA . Clin Infect Dis 2018 68 (1) 5-12 Background: The burden and epidemiology of Mycoplasma pneumoniae (Mp) among U.S. children (<18 years) hospitalized with community-acquired pneumonia (CAP) are poorly understood. Methods: In the Etiology of Pneumonia in the Community (EPIC) study, we prospectively enrolled 2254 children hospitalized with radiographically-confirmed pneumonia from January 2010-June 2012 and tested nasopharyngeal/oropharyngeal swabs for Mp using real-time polymerase chain reaction (PCR). Clinical and epidemiological features of Mp-PCR-positive and -negative children were compared using logistic regression. Macrolide susceptibility was assessed by genotyping isolates. Results: In the EPIC study, 182(8%) children were Mp-PCR-positive (median age: 7 years); 12% required intensive care and 26% had pleural effusion. No in-hospital deaths occurred. Macrolide resistance was found in 6/169(4%) isolates. Of 178(98%) Mp-PCR-positive children tested for co-pathogens, 50(28%) had >/=1 co-pathogen detected. Variables significantly associated with higher odds of Mp detection included age {10-17 years [adjusted odds ratio (aOR): 7.9 (95% confidence interval (CI): 4.5-13.6)] and 5-9 years [aOR: 4.8 (CI: 2.9-7.8)] vs. 2-4 years}, outpatient antibiotics </=5 days pre-admission [aOR: 2.3 (CI: 1.5-3.4)], and co-pathogen detection [aOR: 2.1 (CI: 1.3-3.1)]. Clinical characteristics often seen included hilar lymphadenopathy, rales, headache, sore throat, and decreased breath sounds. Conclusions: Usually considered as a mild respiratory infection, M. pneumoniae was the most commonly detected bacteria among children >/=5 years hospitalized with CAP; one-quarter of whom had co-detections. Although associated with clinically non-specific symptoms, there was a need for intensive care support in some cases. M. pneumoniae should be included in the differential diagnosis for school-aged children hospitalized with CAP. |
Epidemiology and Molecular Identification and Characterization of Mycoplasma pneumoniae, South Africa, 2012-2015.
Carrim M , Wolter N , Benitez AJ , Tempia S , du Plessis M , Walaza S , Moosa F , Diaz MH , Wolff BJ , Treurnicht FK , Hellferscee O , Dawood H , Variava E , Cohen C , Winchell JM , von Gottberg A . Emerg Infect Dis 2018 24 (3) 506-513 During 2012-2015, we tested respiratory specimens from patients with severe respiratory illness (SRI), patients with influenza-like illness (ILI), and controls in South Africa by real-time PCR for Mycoplasma pneumoniae, followed by culture and molecular characterization of positive samples. M. pneumoniae prevalence was 1.6% among SRI patients, 0.7% among ILI patients, and 0.2% among controls (p<0.001). Age <5 years (adjusted odd ratio 7.1; 95% CI 1.7-28.7) and HIV infection (adjusted odds ratio 23.8; 95% CI 4.1-138.2) among M. pneumonia-positive persons were associated with severe disease. The detection rate attributable to illness was 93.9% (95% CI 74.4%-98.5%) in SRI patients and 80.7% (95% CI 16.7%-95.6%) in ILI patients. The hospitalization rate was 28 cases/100,000 population. We observed the macrolide-susceptible M. pneumoniae genotype in all cases and found P1 types 1, 2, and a type 2 variant with multilocus variable number tandem repeat types 3/6/6/2, 3/5/6/2, and 4/5/7/2. |
Comparative genome analysis reveals a complex population structure of Legionella pneumophila subspecies.
Kozak-Muiznieks NA , Morrison SS , Mercante JW , Ishaq MK , Johnson T , Caravas J , Lucas CE , Brown E , Raphael BH , Winchell JM . Infect Genet Evol 2018 59 172-185 The majority of Legionnaires' disease (LD) cases are caused by Legionella pneumophila, a genetically heterogeneous species composed of at least 17 serogroups. Previously, it was demonstrated that L. pneumophila consists of three subspecies: pneumophila, fraseri and pascullei. During an LD outbreak investigation in 2012, we detected that representatives of both subspecies fraseri and pascullei colonized the same water system and that the outbreak-causing strain was a new member of the least represented subspecies pascullei. We used partial sequence based typing consensus patterns to mine an international database for additional representatives of fraseri and pascullei subspecies. As a result, we identified 46 sequence types (STs) belonging to subspecies fraseri and two STs belonging to subspecies pascullei. Moreover, a recent retrospective whole genome sequencing analysis of isolates from New York State LD clusters revealed the presence of a fourth L. pneumophila subspecies that we have termed raphaeli. This subspecies consists of 15 STs. Comparative analysis was conducted using the genomes of multiple members of all four L. pneumophila subspecies. Whereas each subspecies forms a distinct phylogenetic clade within the L. pneumophila species, they share more average nucleotide identity with each other than with other Legionella species. Unique genes for each subspecies were identified and could be used for rapid subspecies detection. Improved taxonomic classification of L. pneumophila strains may help identify environmental niches and virulence attributes associated with these genetically distinct subspecies. |
Development of a multiplex TaqMan real-time PCR assay for the detection of Chlamydia psittaci and Chlamydia pneumoniae in human clinical specimens.
Wolff BJ , Morrison SS , Winchell JM . Diagn Microbiol Infect Dis 2017 90 (3) 167-170 Diagnosis of Chlamydia psittaci and Chlamydia pneumoniae infections has traditionally relied on serological assays. We developed a multiplex real-time PCR assay for detection of C. psittaci, C. pneumoniae and an internal control. Results of this assay demonstrated 100% concordance compared to results of previously tested human clinical specimens. |
Distribution of Legionella and bacterial community composition among regionally diverse US cooling towers
Llewellyn AC , Lucas CE , Roberts SE , Brown EW , Nayak BS , Raphael BH , Winchell JM . PLoS One 2017 12 (12) e0189937 Cooling towers (CTs) are a leading source of outbreaks of Legionnaires' disease (LD), a severe form of pneumonia caused by inhalation of aerosols containing Legionella bacteria. Accordingly, proper maintenance of CTs is vital for the prevention of LD. The aim of this study was to determine the distribution of Legionella in a subset of regionally diverse US CTs and characterize the associated microbial communities. Between July and September of 2016, we obtained aliquots from water samples collected for routine Legionella testing from 196 CTs located in eight of the nine continental US climate regions. After screening for Legionella by PCR, positive samples were cultured and the resulting Legionella isolates were further characterized. Overall, 84% (164) were PCR-positive, including samples from every region studied. Of the PCR-positive samples, Legionella spp were isolated from 47% (78), L. pneumophila was isolated from 32% (53), and L. pneumophila serogroup 1 (Lp1) was isolated from 24% (40). Overall, 144 unique Legionella isolates were identified; 53% (76) of these were Legionella pneumophila. Of the 76 L. pneumophila isolates, 51% (39) were Lp1. Legionella were isolated from CTs in seven of the eight US regions examined. 16S rRNA amplicon sequencing was used to compare the bacterial communities of CT waters with and without detectable Legionella as well as the microbiomes of waters from different climate regions. Interestingly, the microbial communities were homogenous across climate regions. When a subset of seven CTs sampled in April and July were compared, there was no association with changes in corresponding CT microbiomes over time in the samples that became culture-positive for Legionella. Legionella species and Lp1 were detected frequently among the samples examined in this first large-scale study of Legionella in US CTs. Our findings highlight that, under the right conditions, there is the potential for CT-related LD outbreaks to occur throughout the US. |
Rapid laboratory identification of Neisseria meningitidis serogroup C as the cause of an outbreak - Liberia, 2017
Patel JC , George J , Vuong J , Potts CC , Bozio C , Clark TA , Thomas J , Schier J , Chang A , Waller JL , Diaz MH , Whaley M , Jenkins LT , Fuller S , Williams DE , Redd JT , Arthur RR , Taweh F , Vera Walker Y , Hardy P , Freeman M , Katawera V , Gwesa G , Gbanya MZ , Clement P , Kohar H , Stone M , Fallah M , Nyenswah T , Winchell JM , Wang X , McNamara LA , Dokubo EK , Fox LM . MMWR Morb Mortal Wkly Rep 2017 66 (42) 1144-1147 On April 25, 2017, a cluster of unexplained illness and deaths among persons who had attended a funeral during April 21-22 was reported in Sinoe County, Liberia (1). Using a broad initial case definition, 31 cases were identified, including 13 (42%) deaths. Twenty-seven cases were from Sinoe County (1), and two cases each were from Grand Bassa and Monsterrado counties, respectively. On May 5, 2017, initial multipathogen testing of specimens from four fatal cases using the Taqman Array Card (TAC) assay identified Neisseria meningitidis in all specimens. Subsequent testing using direct real-time polymerase chain reaction (PCR) confirmed N. meningitidis in 14 (58%) of 24 patients with available specimens and identified N. meningitidis serogroup C (NmC) in 13 (54%) patients. N. meningitidis was detected in specimens from 11 of the 13 patients who died; no specimens were available from the other two fatal cases. On May 16, 2017, the National Public Health Institute of Liberia and the Ministry of Health of Liberia issued a press release confirming serogroup C meningococcal disease as the cause of this outbreak in Liberia. |
Mycoplasma hominis Infections Transmitted Through Amniotic Tissue Product.
Novosad SA , Basavaraju SV , Annambhotla P , Mohr M , Halpin A , Foy L , Chmielewski R , Winchell JM , Benitez AJ , Morrison SS , Johnson T , Crabb DM , Ratliff AE , Waites K , Kuehnert MJ . Clin Infect Dis 2017 65 (7) 1152-1158 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 PCR (qPCR), and whole genome sequencing were performed. Use of this amniotic tissue product was reviewed. A multi-state 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 seven states; at least 20 vials from this donor were used in 14 patients. Of these, 4/14 (29%) developed surgical site infections, including two M. hominis infections. M. hominis was detected by culture and qPCR in two unused vials from the donor. Sequencing indicated >99% similarity between patient and unopened vial isolates. For five of 27 (19%) vials, the final disposition could not be confirmed. Conclusions: M. hominis was transmitted through amniotic tissue from a single donor to two 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. |
Molecular characterization of Mycoplasma pneumoniae infections in two rural populations of Thailand from 2009-2012.
Whistler T , Sawatwong P , Diaz MH , Benitez AJ , Wolff BJ , Sapchookul P , Thamthitiwat S , Winchell JM . J Clin Microbiol 2017 55 (7) 2222-2233 Studies on Mycoplasma pneumoniae in Thailand have focused on urban centers and have not included the molecular characterization. In an attempt to provide a more comprehensive understanding of this organism, we conducted a systematic random sampling to identify 3000 nasopharyngeal swab specimens, collected from January 2009 through July 2012 during population-based surveillance for influenza-like illness in two rural provinces. M. pneumoniae was detected by real-time PCR in 175 (5.8%) specimens. Genotyping was performed using the major adhesion protein (P1) and multilocus variable-number tandem-repeat analysis (MLVA). Of the 157 specimens typed, 97 were P1 type 1 and 60 were P1 type 2. Six different MLVA profiles were identified in 149 specimens with 4/5/7/2 (40%) and 3/5/6/2 (26%) predominating. There was no discrete seasonality to M. pneumoniae infections. Examination of the 23S rRNA sequence for known polymorphisms conferring macrolide resistance revealed all 141 tested to possess the genotype associated with macrolide susceptibility. |
Influence of antibiotics on the detection of bacteria by culture-based and culture-independent diagnostic tests in patients hospitalized with community-acquired pneumonia
Harris AM , Bramley AM , Jain S , Arnold SR , Ampofo K , Self WH , Williams DJ , Anderson EJ , Grijalva CG , McCullers JA , Pavia AT , Wunderink RG , Edwards KM , Winchell JM , Hicks LA . Open Forum Infect Dis 2017 4 (1) ofx014 BACKGROUND: Specimens collected after antibiotic exposure may reduce culture-based bacterial detections. The impact on culture-independent diagnostic tests is unclear. We assessed the effect of antibiotic exposure on both of these test results among patients hospitalized with community-acquired pneumonia (CAP). METHODS: Culture-based bacterial testing included blood cultures and high-quality sputum or endotracheal tube (ET) aspirates; culture-independent testing included urinary antigen testing (adults) for Streptococcus pneumoniae and Legionella pneumophila and polymerase chain reaction (PCR) on nasopharyngeal and oropharyngeal (NP/OP) swabs for Mycoplasma pneumoniae and Chlamydia pneumoniae. The proportion of bacterial detections was compared between specimens collected before and after either any antibiotic exposure (prehospital and/or inpatient) or only prehospital antibiotics and increasing time after initiation of inpatient antibiotics. RESULTS: Of 4678 CAP patients, 4383 (94%) received antibiotics: 3712 (85%) only inpatient, 642 (15%) both inpatient and prehospital, and 29 (<1%) only prehospital. There were more bacterial detections in specimens collected before antibiotics for blood cultures (5.2% vs 2.6%; P < .01) and sputum/ET cultures (50.0% vs 26.8%; P < .01) but not urine antigen (7.0% vs 5.7%; P = .53) or NP/OP PCR (6.7% vs 5.4%; P = .31). For all diagnostic testing, bacterial detections declined with increasing time between inpatient antibiotic administration and specimen collection. CONCLUSIONS: Bacteria were less frequently detected in culture-based tests collected after antibiotics and in culture-independent tests that had longer intervals between antibiotic exposure and specimen collection. Bacterial yield could improve if specimens were collected promptly, preferably before antibiotics, providing data for improved antibiotic selection. |
Comprehensive bioinformatics analysis of Mycoplasma pneumoniae genomes to investigate underlying population structure and type-specific determinants.
Diaz MH , Desai HP , Morrison SS , Benitez AJ , Wolff BJ , Caravas J , Read TD , Dean D , Winchell JM . PLoS One 2017 12 (4) e0174701 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. |
Multi-center evaluation of one commercial and 12 in-house real-time PCR assays for detection of Mycoplasma pneumoniae.
Dumke R , Benitez AJ , Chalker V , Gullsby K , Henrich B , Hidalgo-Grass C , Hoogenboezem T , Kese D , Loens K , Maaskant J , Michael-Gayego A , Moses AE , Nir-Paz R , Pas SD , Pereyre S , Petersen RF , Rosenblatt M , van Rossum AM , Uldum SA , Unger WW , Ursi D , Winchell JM , Bebear C . Diagn Microbiol Infect Dis 2017 88 (2) 111-114 Detection of Mycoplasma pneumoniae by real-time PCR is not yet standardized across laboratories. We have implemented a standardization protocol to compare the performance of thirteen commercial and in-house approaches. Despite differences on threshold values of samples, all assays were able to detect at least 20M. pneumoniae genomes per reaction. |
Complete Genome Sequence of Mycoplasma pneumoniae Type 2 Reference Strain FH Using Single-Molecule Real-Time Sequencing Technology.
Desai HP , Morrison SS , Diaz MH , Benitez AJ , Wolff BJ , Winchell JM . Genome Announc 2017 5 (8) 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. |
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