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Among symptomatic outpatients, subgenomic RNA of severe acute respiratory syndrome coronavirus 2 in nasal midturbinate swab specimens was concordant with antigen detection but remained detectable in 13 (82.1%) of 16 nasopharyngeal swab specimens from antigen-negative persons. Subgenomic RNA in midturbinate swab specimens might be useful for routine diagnostics to identify active virus replication.

Group A Streptococcus (GAS) (Streptococcus pyogenes) is the most common bacterial cause of acute pharyngitis. Diagnosed cases of GAS pharyngitis should be treated with antibiotics to prevent primary and secondary complications. Commonly, testing for GAS pharyngitis can be done rapidly (in minutes) using rapid antigen detection tests (RADTs), which generally have relatively high specificity (>90%) but lower sensitivity (70 to 90%). The low sensitivity of GAS RADTs requires that culture be performed to maximize sensitivity, which delays the final result by 24 to 48 hours. New molecular GAS assays are on the market and offer relatively rapid (i.e., minutes to tens of minutes) and highly sensitive results so that culture is not required for negative results. We describe our experience with moving from RADT and culture testing for GAS to solely molecular testing, providing quicker results for improved patient care.

Noroviruses are a leading cause of acute gastroenteritis (AGE) among adults and children worldwide. NoroSurv is a global network for norovirus strain surveillance among children

We evaluated six commercial molecular tests targeting Mycoplasma pneumoniae, namely, 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 (RUO) PCR, and the SpeeDx Resistance Plus MP assays. 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 PCR (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

Background: Discontinuation of contact precautions for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) have failed to show an increase in associated transmission or infections in adult healthcare settings. Pediatric experience is limited. Objective: We evaluated the impact of discontinuing contact precautions for MRSA, VRE, and extended-spectrum β-lactamase–producing gram-negative bacilli (ESBLs) on device-associated healthcare-associated infections (HAIs). Methods: In October 2018, contact precautions were discontinued for children with MRSA, VRE, and ESBLs in a large, tertiary-care pediatric healthcare system comprising 2 hospitals and 620 beds. Coincident interventions that potentially reduced HAIs included blood culture diagnostic stewardship (June 2018), a hand hygiene education initiative (July 2018), a handshake antibiotic stewardship program (December 2018) and multidisciplinary infection prevention rounding in the intensive care units (November 2018). Compliance with hand hygiene and HAI prevention bundles were monitored. Device-associated HAIs were identified using standard definitions. Annotated run charts were used to track the impact of interventions on changes in device-associated HAIs over time. Results: Average hand hygiene compliance was 91%. Compliance with HAI prevention bundles was 81% for ventilator-associated pneumonias, 90% for catheter-associated urinary tract infections, and 97% for central-line–associated bloodstream infections. Overall, device-associated HAIs decreased from 6.04 per 10,000 patient days to 3.25 per 10,000 patient days after October 2018 (Fig. 1). Prior to October 2018, MRSA, VRE and ESBLs accounted for 10% of device-associated HAIs. This rate decreased to 5% after October 2018. The decrease in HAIs was likely related to interventions such as infection prevention rounds and handshake stewardship. Conclusions: Discontinuation of contact precautions for children with MRSA, VRE, and ESBLs were not associated with increased device-associated HAIs, and such discontinuation is likely safe in the setting of robust infection prevention and antibiotic stewardship programs.Funding: NoneDisclosures: None

Non-Staphylococcus aureus staphylococcal species (non-SASS) are important pathogens in both animal and human populations. The development of β-lactam resistance in non-SASS through acquisition and expression of penicillin-binding protein 2a (PBP2a) represents a significant clinical and public health threat. Here, we evaluated the diagnostic performance of two versions of a PBP2a immunochromatographic assay with non-SASS. Our data show that the revised version of the assay, the PBP2a SA culture colony test, has superior diagnostic sensitivity compared to the previous version of the assay, the PBP2a culture colony test, 100% (95% confidence interval [CI], 93.3 to 100%) versus 67.9% (95% CI, 53.7 to 80.1%), respectively, while both assays display a specificity of 100% (95% CI, 92.5 to 100%). Therefore, the PBP2a SA culture colony test offers a rapid, accurate, and relatively inexpensive method for detecting PBP2a-mediated β-lactam resistance in clinically relevant non-SASS for the management of infections due to these organisms and for antimicrobial stewardship.

Background The reservoir of pathogenic ciprofloxacin-resistant Escherichia coli remains unknown. Methods We conducted a prospective cohort study of 80 healthy twins and their mothers to determine the frequency of excretion of ciprofloxacin-resistant, potentially pathogenic E. coli. Stool specimens were cultured selectively for ciprofloxacin-resistant gram-negative bacteria. Isolates were categorized on the basis of additional resistance and virulence profiles. We also prospectively collected clinical metadata. Results Fifteen children (19%) and 8 mothers (20%) excreted ciprofloxacin-resistant E. coli at least once. Overall, 33% of 40 families had at least 1 member whose stool specimen yielded ciprofloxacin-resistant E. coli on culture. Fifty-seven submitted stool specimens (2.8%) contained such organisms; clones ST131-H30 and ST405 accounted for 52 and 5 of the positive specimens, respectively. Length of hospital stay after birth (P = .002) and maternal colonization (P = .0001) were associated with subsequent childhood carriage of ciprofloxacin-resistant E. coli; antibiotic use, acid suppression, sex, mode of delivery, and maternal perinatal antibiotic use were not. Ciprofloxacin-resistant E. coli were usually resistant to additional antibiotic classes, and all had virulence genotypes typical of extraintestinal pathogenic E. coli. Conclusions Healthy children and their mothers commonly harbor ciprofloxacin-resistant E. coli with pathogenic potential.

Clinical laboratory workers encounter a variety of occupational hazards, including exposure to infectious agents. The routes of pathogen exposure associated with laboratory work include ingestion, inhalation, direct inoculation, and contamination of skin and mucous membranes (1). The accidental inoculation of infectious materials (i.e., via contaminated needles, broken glass, or other sharps) is the leading cause of laboratory-associated infections (1). In the 1980s, the emergence of the HIV epidemic created an appreciation for biosafety and laboratory-acquired infections, ultimately leading to both practice guidelines and legislation to reduce the risk of exposure of laboratory workers to bloodborne pathogens; this was implemented by the adoption of Universal Precautions in 1987, and later, in 1996, these became a component of Standard Precautions (2). The actual incidence and risk of laboratory-acquired infections is very difficult to quantify in the absence of standardized reporting systems, as well as the challenge of attributing a specific exposure to acquisition of infection. The most comprehensive studies to date attempting to estimate the incidence and epidemiology of laboratory-acquired infections were completed prior to 1980, and it is difficult to generalize them to today's laboratory environment, for a variety of reasons—standards for personal protective equipment have changed, the availability of vaccines, the epidemiology of bloodborne infections has changed, and the way laboratory testing is performed has changed (with a shift away from primarily manual methods to more automated methods). That said, since 1999, only 1 confirmed case of laboratory-acquired HIV infection has been reported in the US; this case was secondary to a needle stick injury sustained in an individual working with a live HIV culture (2). The fear associated with the recent Ebola virus (EV)3 epidemic triggered a renewed interest in occupationally acquired infections in healthcare workers in the US, including the safety of laboratory workers in …

Sepsis is a global problem and laboratory methods must be optimized to effect rapid, positive patient outcomes. The proverbial reference standard method for diagnosis, the actual culture of blood, suffers from a variety of preanalytical issues such as sufficient blood volume, prior antimicrobial treatment, time from sampling to incubation, and analytical issues of prolonged turnaround time until final identification and availability of antimicrobial susceptibility testing results. Advancements have occurred in molecular methods to provide rapid microorganism identification and resistance gene detection (e.g., mecA in Staphylococcus spp.) from positive blood culture broths. In a meta-analysis of these new methods, a significant reduction in time to targeted treatment was observed ( 1 ). However, these methods are dependent on having a positive blood culture, which is subject to the preanalytical issues described above. The ability to directly identify pathogens from blood specimens would greatly reduce the time to identification and time to optimization of therapy, as well as potentially contributing to avoiding unnecessary antimicrobials and/or discontinuation of treatment in patients with negative testing results. Direct detection methods for viruses from patient specimens have benefited from advances in molecular methods, which is largely because of the high viral loads present in those specimens. In contrast, the majority of septic patients have a paucity of bacteria or fungi per milliliter of blood, necessitating the need for larger blood volumes to increase blood culture sensitivity ( 2 – 4 ).

Norovirus is the most common cause of sporadic gastroenteritis and outbreaks worldwide. The rapid identification of norovirus has important implications for infection prevention measures and may reduce the need for additional diagnostic testing. The Xpert Norovirus assay recently received FDA clearance for the detection and differentiation of norovirus genogroups I and II (GI and GII), which account for the vast majority of infections. In this study, we evaluated the performance of the Xpert Norovirus assay with both fresh, prospectively collected ( n = 914) and frozen, archived ( n = 489) fecal specimens. A Centers for Disease Control and Prevention (CDC) composite reference method was used as the gold standard for comparison. For both prospective and frozen specimens, the Xpert Norovirus assay showed positive percent agreement (PPA) and negative percent agreement (NPA) values of 98.3% and 98.1% for GI and of 99.4% and 98.2% for GII, respectively. Norovirus prevalence in the prospective specimens (collected from March to May of 2014) was 9.9% ( n = 90), with the majority of positives caused by genogroup II (82%, n = 74). The positive predictive value (PPV) of the Xpert Norovirus assay was 75% for GI-positive specimens, whereas it was 86.5% for GII-positive specimens. The negative predictive values (NPV) for GI and GII were 100% and 99.9%, respectively.

In order to divide, the bacterium Escherichia coli must assemble a set of at least 10 essential proteins at the nascent division site. These proteins localize to midcell according to a linear hierarchy, suggesting that cell division proteins are added to the nascent divisome in strict sequence. We previously described a method, 'premature targeting', which allows us to target a protein directly to the division site independently of other cell division proteins normally required for its localization at midcell. By systematically applying this method to probe the recruitment of and associations among late cell division proteins, we show that this linear assembly model is likely incorrect. Rather, we find that the assembly of most of the late proteins can occur independently of 'upstream' proteins. Further, most late proteins, when prematurely targeted to midcell, can back-recruit upstream proteins in the reverse of the predicted pathway. Together these observations indicate that the late proteins, with the notable exception of the last protein in the pathway, FtsN, are associated in a hierarchical set of protein complexes. Based on these observations we present a revised model for assembly of the E. coli division apparatus.

We report two cases of bacteremia with Actinobaculum schaalii, a rarely reported, anaerobic, Gram-positive bacterium. The first case was a patient with renal cancer who developed pyelonephritis after cryoablation, and the second was a patient who developed sepsis after a urogenital procedure. Bacteremia resolved after administration of empiric antibiotic therapy.

In this study, we investigated the requirement of theListeria monocytogenesbroad-range phospholipase C (PC-PLC) during infection of human epithelial cells.L. monocytogenesis a facultative intracellular bacterial pathogen of humans and a variety of animal species. After entering a host cell,L. monocytogenesis initially surrounded by a membrane-bound vacuole. Bacteria promote their escape from this vacuole, grow within the host cell cytosol, and spread from cell to cell via actin-based motility. Most infection studies withL. monocytogeneshave been performed with mouse cells or an in vivo mouse model of infection. In all mouse-derived cells tested, the pore-forming cytolysin listeriolysin O (LLO) is absolutely required for lysis of primary vacuoles formed during host cell entry. However,L. monocytogenescan escape from primary vacuoles in the absence of LLO during infection of human epithelial cell lines Henle 407, HEp-2, and HeLa. Previous studies have shown that the broad-range phospholipase C, PC-PLC, promotes lysis of Henle 407 cell primary vacuoles in the absence of LLO. Here, we have shown that PC-PLC is also required for lysis of HEp-2 and HeLa cell primary vacuoles in the absence of LLO expression. Furthermore, our results indicated that the amount of PC-PLC activity is critical for the efficiency of vacuolar lysis. In an LLO-negative derivative ofL. monocytogenesstrain 10403S, expression of PC-PLC has to increase before or upon entry into human epithelial cells, compared to expression in broth culture, to allow bacterial escape from primary vacuoles. Using a system for inducible PC-PLC expression inL. monocytogenes, we provide evidence that phospholipase activity can be increased by elevated expression of PC-PLC or Mpl, the enzyme required for proteolytic activation of PC-PLC. Lastly, by using the inducible PC-PLC expression system, we demonstrate that, in the absence of LLO, PC-PLC activity is not only required for lysis of primary vacuoles in human epithelial cells but is also necessary for efficient cell-to-cell spread. We speculate that the additional requirement for PC-PLC activity is for lysis of secondary double-membrane vacuoles formed during cell-to-cell spread.