Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 41
Filter
1.
J Family Med Prim Care ; 13(5): 2006-2014, 2024 May.
Article in English | MEDLINE | ID: mdl-38948571

ABSTRACT

Background: The role of caregivers in grooming the neuro-developmental outcome of high-risk newborns and developmental challenges in children needs to be explored. Objectives: To find the knowledge and perception among parents regarding the neuro-developmental outcome of high-risk newborns, methods adopted to address these problems, and to identify areas on which awareness generation needs to focus. Materials and Methods: A questionnaire-based awareness survey was conducted to understand the knowledge, attitude, and practices of families of children with developmental challenges. Results: The study revealed that more than 70 percent of families lack information about child development, developmental challenges, and means to deal with them. They are unaware of the available health care services and other resources. One in three families has misconceptions on developmental disabilities; consider them as curse or jinx and consequently neglected. Female children with developmental problems are further ostracized due to gender inequity in families. About 10 percent of families have shown great openness toward acquiring new skills and knowledge for handling their children with developmental delays. Conclusions: This study is based on the précis research findings of our grass-root level fieldwork conducted in remote rural Bengal areas. The observation will be of interest and learning materials for general primary care practitioners, family physicians, and stakeholders to initiate appropriate intervention strategies for properly rehabilitating children with developmental delay at grass-root levels of primary health care.

2.
Article in English | MEDLINE | ID: mdl-38156208

ABSTRACT

The COVID-19 pandemic led to an initial increase in the incidence of carbapenem-resistant Enterobacterales (CRE) from clinical cultures in South-East Asia hospitals, which was unsustained as the pandemic progressed. Conversely, there was a decrease in CRE incidence from surveillance cultures and overall combined incidence. Further studies are needed for future pandemic preparedness.

3.
J Clin Microbiol ; 61(9): e0031623, 2023 09 21.
Article in English | MEDLINE | ID: mdl-37671882

ABSTRACT

NG-Test CARBA 5 (NG-Biotech) is a rapid in vitro multiplex immunoassay for the phenotypic detection and differentiation of the "big five" carbapenemase families (KPC, OXA-48-like, VIM, IMP, and NDM). Version 2 of this assay was evaluated alongside the Xpert Carba-R assay (Cepheid, Inc.), the modified carbapenem inactivation method (mCIM), and the CIMTris assay, with a collection of carbapenem-resistant non-fermenting Gram-negative bacilli comprising 138 Pseudomonas aeruginosa and 97 Acinetobacter baumannii isolates. Whole-genome sequencing (WGS) was used as the reference standard. For P. aeruginosa, NG-Test CARBA 5 produced an overall percentage agreement (OPA) with WGS of 97.1%, compared with 92.8% forXpert Carba-R and 90.6% for mCIM. For A. baumannii, as OXA-type carbapenemases (non-OXA-48) are not included, both the NG-Test CARBA 5 and Xpert Carba-R only had an OPA of 6.2%, while the CIMTris performed well with an OPA of 99.0%. The majority of A. baumannii isolates (95.9%) tested falsely positive for IMP on NG-Test CARBA 5; no IMP genes were found on WGS. No clear cause was found for this phenomenon; a cross-reacting protein antigen unique to A. baumannii is a possible culprit. NG-Test CARBA 5 performed well for carbapenemase detection in P. aeruginosa. However, results from A. baumannii isolates should be interpreted with caution.


Subject(s)
Bacterial Proteins , beta-Lactamases , Humans , Bacterial Proteins/genetics , beta-Lactamases/genetics , Whole Genome Sequencing , Carbapenems/pharmacology , Gram-Negative Bacteria/genetics , Pseudomonas aeruginosa/genetics
5.
J Antimicrob Chemother ; 78(10): 2515-2523, 2023 10 03.
Article in English | MEDLINE | ID: mdl-37596905

ABSTRACT

OBJECTIVES: The blaZ gene encodes penicillinase, which inactivates penicillin. As there were reports on suboptimal sensitivity for the penicillin zone-edge test, a phenotypic method for blaZ detection, we investigated treatment outcomes in patients with penicillin-susceptible Staphylococcus aureus (PSSA) bacteraemia (phenotypically negative for penicillinase), subjecting isolates to molecular testing for blaZ retrospectively. PATIENTS AND METHODS: A retrospective cohort study was conducted on 121 patients with a first episode of PSSA bacteraemia from 1 January 2012 to 31 October 2015 at Tan Tock Seng Hospital (TTSH), Singapore. Patients were grouped into IV benzylpenicillin and non-benzylpenicillin groups. The primary outcome was overall treatment failure, defined as either 30 day all-cause mortality and/or 90 day relapse. The penicillin (P10) zone-edge test was repeated on archived PSSA isolates, concurrently with penicillin MIC determination via gradient diffusion and PCR for blaZ. RESULTS: Among 121 patients, 57 patients (47.1%) received IV benzylpenicillin as the predominant antibiotic. There was no significant difference in overall treatment failure between treatment with the benzylpenicillin [7/57 (12.3%)] versus non-benzylpenicillin groups [12/64 (18.8%)] (P = 0.33) or cloxacillin/cefazolin [6/37 (16.2%)] (P = 0.59). For 112 PSSA isolates available for testing, repeat penicillin zone-edge testing was negative for penicillinase production, corroborating previous results. A single PSSA isolate with a negative penicillin zone-edge test was found to be positive for blaZ. CONCLUSIONS: We found no differences in overall treatment failure between patients with PSSA bacteraemia treated with benzylpenicillin, anti-staphylococcal ß-lactams cefazolin/cloxacillin and other antimicrobials, when using the penicillin zone-edge test as the phenotypic method for blaZ screening.


Subject(s)
Bacteremia , Staphylococcal Infections , Humans , Anti-Bacterial Agents/therapeutic use , Penicillins/therapeutic use , Staphylococcus aureus/genetics , Retrospective Studies , Cefazolin , Penicillinase , Penicillin G/therapeutic use , Staphylococcal Infections/drug therapy , Bacteremia/drug therapy , Treatment Outcome , Cloxacillin , Microbial Sensitivity Tests
6.
ACS Sens ; 8(8): 3136-3145, 2023 08 25.
Article in English | MEDLINE | ID: mdl-37477562

ABSTRACT

Urinary tract infection (UTI) diagnosis based on urine culture for bacteriuria analysis is time-consuming and often leads to wastage of hospital resources due to false-positive UTI cases. Direct cellular phenotyping (e.g., RBCs, neutrophils, epithelial cells) of urine samples remains a technical challenge as low cell concentrations, and urine characteristics (conductivities, pH, microbes) can affect the accuracy of cell measurements. In this work, we report a microfluidic inertial-impedance cytometry technique for label-free rapid (<5 min) neutrophil sorting and impedance profiling from urine directly. Based on size-based inertial focusing effects, neutrophils are isolated, concentrated, and resuspended in saline (buffer exchange) to improve consistency in impedance-based single-cell analysis. We first observed that both urine pH and the presence of bacteria can affect neutrophil high-frequency impedance measurements possibly due to changes in nucleus morphology as neutrophils undergo NETosis and phagocytosis, respectively. As a proof-of-concept for clinical testing, we report for the first time, rapid UTI testing based on multiparametric impedance profiling of putative neutrophils (electrical size, membrane properties, and distribution) in urine samples from non-UTI (n = 20) and UTI patients (n = 20). A significant increase in cell count was observed in UTI samples, and biophysical parameters were used to develop a UTI classifier with an area under the receiver operating characteristic curve of 0.84. Overall, the developed platform facilitates rapid culture-free urine screening which can be further developed to assess disease severity in UTI and other urologic diseases based on neutrophil electrical signatures.


Subject(s)
Bacteriuria , Urinary Tract Infections , Humans , Electric Impedance , Microfluidics , Urinary Tract Infections/diagnosis , Urinary Tract Infections/microbiology , Urinary Tract Infections/urine , Bacteriuria/diagnosis , Bacteriuria/urine , Urinalysis/methods
7.
Microbiol Resour Announc ; 12(6): e0016723, 2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37166299

ABSTRACT

We report the draft genome sequences of two Phytobacter diazotrophicus isolates recovered from a swab specimen from the water faucet located in the Neonatal Intensive Care Unit (ICU), National University Hospital, Singapore. The isolates were misidentified as Cronobacter sakazakii and Klebsiella oxytoca using biochemical methods. Whole-genome sequencing (WGS) was performed to determine their identity.

8.
Microbiol Spectr ; 11(3): e0403322, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37042789

ABSTRACT

Pseudomonas aeruginosa ST308 clone has been reported to carry carbapenemase genes such as blaIMP and blaVIM but has been rarely associated with blaNDM-1. A total of 199 P. aeruginosa ST308 clinical and environmental isolates obtained between April 2019 and November 2020 from a tertiary-care hospital in Singapore were characterized using whole-genome sequencing. In addition, 71 blaNDM-1-positive ST308 whole-genome sequences from two other local tertiary-care hospitals in Singapore and 83 global blaNDM-1-negative ST308 whole-genome sequences in public databases were included to assess phylogenetic relationships and perform genome analyses. Phylogenetic analysis and divergent time estimation revealed that blaNDM-1-positive P. aeruginosa ST308 was introduced into Singapore in 2005 (95 % highest posterior density: 2001 to 2008). Core genome, resistome, and analyses of all local blaNDM-1-positive ST308 isolates showed chromosomal integration of multiple antibiotic resistance genes (ARGs) [aac(3)-Id, aac(6')-Il, aadA6, aadA11, dfrB5, msr(E), floR, sul2, and qnrVC1], which was absent in global blaNDM-1-negative ST308 sequences. Most ARGs and virulence genes were conserved across isolates originating from the three different local hospitals. Close genetic relatedness of the blaNDM-1-positive ST308 clinical and environmental isolates suggests cocirculation between the hospital environment and human hosts with the hospital environment as a potential reservoir. Core genome single nucleotide polymorphism analyses revealed possible clonal transmission of blaNDM-1-positive ST308 isolates between the three hospitals over 7 years. Bloodstream isolates accounted for six of 95 (6.3%) clinical isolates. This study reports the introduction of a pathogenic blaNDM-1-positive P. aeruginosa ST308 more than a decade ago in Singapore and warrants surveillance for wider dissemination. IMPORTANCE P. aeruginosa is a Gram-negative opportunistic pathogen ubiquitously found in the environment and a major cause of nosocomial infections. While the P. aeruginosa ST308 clone has been known to bear blaIMP and blaVIM among global isolates, reports of blaNDM-1-positive P. aeruginosa ST308 are rare. The local blaNDM-1-positive P. aeruginosa ST308 isolates detected in this study appear to be unique to this region, with evidence of chromosomal acquisition of multiple ARGs compared to global blaNDM-1-negative P. aeruginosa ST308 isolates. Surveillance in Singapore and beyond for dissemination is essential to determine whether existing measures are sufficient to control the spread of this ST308 clone.


Subject(s)
Pseudomonas Infections , Pseudomonas aeruginosa , Humans , Pseudomonas aeruginosa/genetics , Singapore/epidemiology , Phylogeny , Pseudomonas Infections/epidemiology , Anti-Bacterial Agents/pharmacology , beta-Lactamases/genetics , Microbial Sensitivity Tests
9.
Infect Control Hosp Epidemiol ; 44(3): 460-466, 2023 03.
Article in English | MEDLINE | ID: mdl-35603837

ABSTRACT

OBJECTIVE: In our center, previous infection prevention and control (IPC) resources were concentrated on multidrug-resistant organisms other than CRAB because the rate of CRAB was stable with no evidence of outbreaks. Triggered by an increase in the baseline rate of CRAB isolated in clinical cultures, we investigated horizontal transmission of CRAB to guide targeted IPC actions. METHODS: We prospectively collected clinical data of patients with positive CRAB cultures. We identified genetic relatedness of CRAB isolates using whole-genome sequencing. Findings were regularly presented to the IPC committee, and follow-up actions were documented. RESULTS: During the study period, 66 CRAB isolates were available for WGS. Including 12 clinical isolates and 10 environmental isolates from a previous study, a total of 88 samples were subjected to WGS, of which 83 were successfully sequenced and included in the phylogenetic analysis. We identified 5 clusters involving 44 patients. Genomic transmissions were explained by spatiotemporal overlap in 12 patients and by spatial overlap only in 12 patients. The focus of transmission was deduced to be the intensive care units. One cluster was related to a retrospective environmental isolate, suggesting the environment as a possible route of transmission. Discussion of these findings at multidisciplinary IPC meetings led to implementation of measures focusing on environmental hygiene, including hydrogen peroxide vapor disinfection in addition to terminal cleaning for rooms occupied by CRAB patients. CONCLUSIONS: We showed that WGS could be utilized as a "tool of persuasion" by demonstrating the presence of ongoing transmission of CRAB in an endemic setting, and by identifying actionable routes of transmission for directed IPC interventions.


Subject(s)
Acinetobacter Infections , Acinetobacter baumannii , Cross Infection , Humans , Acinetobacter baumannii/genetics , Retrospective Studies , Phylogeny , Cross Infection/epidemiology , Cross Infection/prevention & control , Acinetobacter Infections/epidemiology , Microbial Sensitivity Tests , Carbapenems/pharmacology , Genomics
10.
Nat Commun ; 13(1): 3052, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35650193

ABSTRACT

Carbapenemase-producing Enterobacterales (CPE) infection control practices are based on the paradigm that detected carriers in the hospital transmit to other patients who stay in the same ward. The role of plasmid-mediated transmission at population level remains largely unknown. In this retrospective cohort study over 4.7 years involving all multi-disciplinary public hospitals in Singapore, we analysed 779 patients who acquired CPE (1215 CPE isolates) detected by clinical or surveillance cultures. 42.0% met putative clonal transmission criteria, 44.8% met putative plasmid-mediated transmission criteria and 13.2% were unlinked. Only putative clonal transmissions associated with direct ward contact decreased in the second half of the study. Both putative clonal and plasmid-mediated transmission associated with indirect (no temporal overlap in patients' admission period) ward and hospital contact did not decrease during the study period. Indirect ward and hospital contact were identified as independent risk factors associated with clonal transmission. In conclusion, undetected CPE reservoirs continue to evade hospital infection prevention measures. New measures are needed to address plasmid-mediated transmission, which accounted for 50% of CPE dissemination.


Subject(s)
Enterobacteriaceae Infections , Gammaproteobacteria , Bacterial Proteins , Enterobacteriaceae Infections/microbiology , Enterobacteriaceae Infections/transmission , Gammaproteobacteria/genetics , Humans , Retrospective Studies , Whole Genome Sequencing , beta-Lactamases/genetics
13.
Clin Infect Dis ; 74(10): 1850-1854, 2022 05 30.
Article in English | MEDLINE | ID: mdl-34554228

ABSTRACT

We studied the performance of an algorithm combining multiplex polymerase chain reaction with phenotypic detection of extended-spectrum ß-lactamases and carbapenemases directly from positive blood culture bottles in patients with gram-negative bacteremia and found good concordance with routine cultures. Such an algorithm may be a tool to improve time to optimal therapy in patients with gram-negative bacteremia.


Subject(s)
Bacteremia , Multiplex Polymerase Chain Reaction , Algorithms , Bacteremia/diagnosis , Bacterial Proteins , Blood Culture , Gram-Negative Bacteria/genetics , Humans , Microbial Sensitivity Tests , beta-Lactamases/genetics
15.
Biomaterials ; 273: 120794, 2021 06.
Article in English | MEDLINE | ID: mdl-33887644

ABSTRACT

Zwitterionic polymers are classical antifouling polymers but they require specialized monomers that have cationic and anionic charges integrated into a single monomer. Herein, we show that pseudo-zwitterionic copolymers synthesized from a mixture of 2 monomers each having a single opposite polarity has excellent antibiofilm efficacy. We have discovered a new mixed-charge copolymer brush (#1-A) synthesized from 2 oppositely charged monomers, the anionic SPM (3-Sulfopropyl methacrylate) and the cationic AMPTMA ((3-Acrylamidopropyl) trimethylammonium chloride), that achieves broad spectrum in vitro antibiofilm effect of greater than 99% reductions against all six Gram-positive and Gram-negative bacteria tested. In the murine subcutaneous wound catheter infection models, the #1-A has good long-term anti-biofilm efficacy against MRSA and Pseudomonas aeruginosa of 3.41 and 3.19 orders respectively, outperforming previous mixed-charge copolymer coatings. We discovered a new method to choose the cationic/anionic pair combination to form the best antibiofilm copolymer brush coating by exploiting the solution polymerization kinetics disparity between the cationic and anionic monomers. We also showed that #1-A is softer and has higher hydration than the classical zwitterionic polymer. This study shows the possibility of achieving potent antibiofilm efficacy by combining readily available opposite singly charged monomers.


Subject(s)
Anti-Bacterial Agents , Gram-Negative Bacteria , Animals , Anti-Bacterial Agents/pharmacology , Biofilms , Gram-Positive Bacteria , Mice , Polymers
16.
ACS Appl Mater Interfaces ; 13(2): 3237-3245, 2021 Jan 20.
Article in English | MEDLINE | ID: mdl-33405504

ABSTRACT

Cationic polymers are promising antibacterial agents because bacteria have a low propensity to develop resistance against them, but they usually have low biocompatibility because of their hydrophobic moieties. Herein, we report a new biodegradable and biocompatible chitosan-derived cationic antibacterial polymer, 2,6-diamino chitosan (2,6-DAC). 2,6-DAC shows excellent broad-spectrum antimicrobial activity with minimum inhibitory concentrations (MICs) of 8-32 µg/mL against clinically relevant and multidrug-resistant (MDR) bacteria including Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Furthermore, 2,6-DAC shows an excellent synergistic effect with various clinically relevant antibiotics proved by decreasing the MICs of the antibiotics against MDR A. baumannii and methicillin-resistant Staphylococcus aureus to <1 µg/mL. In vivo biocompatibility of 2,6-DAC is proved by a dosage of 100 mg/kg compound via oral administration and 25 mg/kg compound via intraperitoneal injection to mice; 2,6-DAC does not cause any weight loss and any significant change in liver and kidney biomarkers or the important blood electrolytes. The combinations of 2,6-DAC together with novobiocin and rifampicin show >2.4 log10 reduction of A. baumannii in murine intraperitoneal and lung infection models. The novel chitosan derivative, 2,6-DAC, can be utilized as a biocompatible broad-spectrum cationic antimicrobial agent alone or in synergistic combination with various antibiotics.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Chitosan/analogs & derivatives , Chitosan/pharmacology , Animals , Bacterial Infections/drug therapy , Drug Synergism , Female , Humans , Methicillin-Resistant Staphylococcus aureus/drug effects , Mice, Inbred BALB C , Microbial Sensitivity Tests
17.
ACS Cent Sci ; 6(11): 2031-2045, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-33274280

ABSTRACT

Gram-negative bacteria cannot be easily eradicated by antibiotics and are a major source of recalcitrant infections of indwelling medical devices. Among various device-associated infections, intravascular catheter infection is a leading cause of mortality. Prior approaches to surface modification, such as antibiotics impregnation, hydrophilization, unstructured NO-releasing, etc., have failed to achieve adequate infection-resistant coatings. We report a precision-structured diblock copolymer brush (H(N)-b-S) composed of a surface antifouling block of poly(sulfobetaine methacrylate) (S) and a subsurface bactericidal block (H(N)) of nitric-oxide-emitting functionalized poly(hydroxyethyl methacrylate) (H) covalently grafted from the inner and outer surfaces of a polyurethane catheter. The block copolymer architecture of the coating is important for achieving good broad-spectrum anti-biofilm activity with good biocompatibility and low fouling. The coating procedure is scalable to clinically useful catheter lengths. Only the block copolymer brush coating ((H(N)-b-S)) shows unprecedented, above 99.99%, in vitro biofilm inhibition of Gram-positive and Gram-negative bacteria, 100-fold better than previous coatings. It has negligible toxicity toward mammalian cells and excellent blood compatibility. In a murine subcutaneous infection model, it achieves >99.99% biofilm reduction of Gram-positive and Gram-negative bacteria compared with <90% for silver catheter, while in a porcine central venous catheter infection model, it achieves >99.99% reduction of MRSA with 5-day implantation. This precision coating is readily applicable for long-term biofilm-resistant and blood-compatible copolymer coatings covalently grafted from a wide range of medical devices.

18.
Proc Natl Acad Sci U S A ; 117(49): 31376-31385, 2020 12 08.
Article in English | MEDLINE | ID: mdl-33229526

ABSTRACT

For a myriad of different reasons most antimicrobial peptides (AMPs) have failed to reach clinical application. Different AMPs have different shortcomings including but not limited to toxicity issues, potency, limited spectrum of activity, or reduced activity in situ. We synthesized several cationic peptide mimics, main-chain cationic polyimidazoliums (PIMs), and discovered that, although select PIMs show little acute mammalian cell toxicity, they are potent broad-spectrum antibiotics with activity against even pan-antibiotic-resistant gram-positive and gram-negative bacteria, and mycobacteria. We selected PIM1, a particularly potent PIM, for mechanistic studies. Our experiments indicate PIM1 binds bacterial cell membranes by hydrophobic and electrostatic interactions, enters cells, and ultimately kills bacteria. Unlike cationic AMPs, such as colistin (CST), PIM1 does not permeabilize cell membranes. We show that a membrane electric potential is required for PIM1 activity. In laboratory evolution experiments with the gram-positive Staphylococcus aureus we obtained PIM1-resistant isolates most of which had menaquinone mutations, and we found that a site-directed menaquinone mutation also conferred PIM1 resistance. In similar experiments with the gram-negative pathogen Pseudomonas aeruginosa, PIM1-resistant mutants did not emerge. Although PIM1 was efficacious as a topical agent, intraperitoneal administration of PIM1 in mice showed some toxicity. We synthesized a PIM1 derivative, PIM1D, which is less hydrophobic than PIM1. PIM1D did not show evidence of toxicity but retained antibacterial activity and showed efficacy in murine sepsis infections. Our evidence indicates the PIMs have potential as candidates for development of new drugs for treatment of pan-resistant bacterial infections.


Subject(s)
Anti-Bacterial Agents/pharmacology , Designer Drugs/pharmacology , Imidazoles/pharmacology , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/therapeutic use , Cell Death/drug effects , Cell Line , Cell Membrane/drug effects , Designer Drugs/chemistry , Designer Drugs/therapeutic use , Humans , Hydrophobic and Hydrophilic Interactions , Imidazoles/chemistry , Imidazoles/therapeutic use , Membrane Potentials/drug effects , Mice , Microbial Sensitivity Tests , Microbial Viability/drug effects , Pseudomonas Infections/drug therapy , Pseudomonas Infections/microbiology , Pseudomonas Infections/pathology , Pseudomonas aeruginosa/drug effects , Sepsis/drug therapy , Sepsis/prevention & control , Skin/drug effects , Skin/microbiology , Skin/pathology
19.
Open Forum Infect Dis ; 7(9): ofaa335, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32964061

ABSTRACT

BACKGROUND: The performance of real-time reverse transcription polymerase chain reaction (rRT-PCR) for SARS-CoV-2 varies with sampling site(s), illness stage, and infection site. METHODS: Unilateral nasopharyngeal, nasal midturbinate, throat swabs, and saliva were simultaneously sampled for SARS-CoV-2 rRT-PCR from suspected or confirmed cases of COVID-19. True positives were defined as patients with at least 1 SARS-CoV-2 detected by rRT-PCR from any site on the evaluation day or at any time point thereafter, until discharge. Diagnostic performance was assessed and extrapolated for site combinations. RESULTS: We evaluated 105 patients; 73 had active SARS-CoV-2 infection. Overall, nasopharyngeal specimens had the highest clinical sensitivity at 85%, followed by throat, 80%, midturbinate, 62%, and saliva, 38%-52%. Clinical sensitivity for nasopharyngeal, throat, midturbinate, and saliva was 95%, 88%, 72%, and 44%-56%, respectively, if taken ≤7 days from onset of illness, and 70%, 67%, 47%, 28%-44% if >7 days of illness. Comparing patients with upper respiratory tract infection (URTI) vs pneumonia, clinical sensitivity for nasopharyngeal, throat, midturbinate, and saliva was 92% vs 70%, 88% vs 61%, 70% vs 44%, 43%-54% vs 26%-45%, respectively. A combination of nasopharyngeal plus throat or midturbinate plus throat specimen afforded overall clinical sensitivities of 89%-92%; this rose to 96% for persons with URTI and 98% for persons ≤7 days from illness onset. CONCLUSIONS: Nasopharyngeal specimens, followed by throat specimens, offer the highest clinical sensitivity for COVID-19 diagnosis in early illness. Clinical sensitivity improves and is similar when either midturbinate or nasopharyngeal specimens are combined with throat specimens. Upper respiratory specimens perform poorly if taken after the first week of illness or if there is pneumonia.

20.
Nat Commun ; 11(1): 2800, 2020 05 29.
Article in English | MEDLINE | ID: mdl-32472043

ABSTRACT

Understanding the particle size distribution in the air and patterns of environmental contamination of SARS-CoV-2 is essential for infection prevention policies. Here we screen surface and air samples from hospital rooms of COVID-19 patients for SARS-CoV-2 RNA. Environmental sampling is conducted in three airborne infection isolation rooms (AIIRs) in the ICU and 27 AIIRs in the general ward. 245 surface samples are collected. 56.7% of rooms have at least one environmental surface contaminated. High touch surface contamination is shown in ten (66.7%) out of 15 patients in the first week of illness, and three (20%) beyond the first week of illness (p = 0.01, χ2 test). Air sampling is performed in three of the 27 AIIRs in the general ward, and detects SARS-CoV-2 PCR-positive particles of sizes >4 µm and 1-4 µm in two rooms, despite these rooms having 12 air changes per hour. This warrants further study of the airborne transmission potential of SARS-CoV-2.


Subject(s)
Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Environmental Microbiology , Patients' Rooms , Pneumonia, Viral/virology , Adult , COVID-19 , Coronavirus Infections/epidemiology , Coronavirus Infections/pathology , Coronavirus Infections/transmission , Cross-Sectional Studies , Female , Hospitals , Humans , Male , Middle Aged , Pandemics , Particle Size , Particulate Matter/analysis , Particulate Matter/chemistry , Pneumonia, Viral/epidemiology , Pneumonia, Viral/pathology , Pneumonia, Viral/transmission , SARS-CoV-2 , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...