No abstract

Molecular typing techniques have been used in outbreak investigations. In this study, molecular typing techniques were used to track the spread of gram-negative rods (GNRs) in a neonatal intensive care unit (NICU) in the absence of an outbreak. Stool or rectal swab cultures for GNRs were obtained from all infants on admission, weekly, and on discharge. GNRs were tested for gentamicin susceptibility and were typed by contour-clamped homogeneous electric field electrophoresis. Transmission of identical strains of GNRs among infants was noted. Shared strains were more gentamicin resistant compared with unique strains (53% vs. 10%; P=.0001). Infants first colonized when they were >1 week of age had more total days of antibiotic treatment and had a higher rate of acquiring a shared and gentamicin-resistant strain, compared with infants colonized earlier. Antibiotic use increases colonization of infants in the NICU with resistant and shared strains of GNRs.

OBJECTIVETo evaluate ultraviolet C (UV-C) irradiance, UV-C dosage, and antimicrobial effect achieved by a mobile continuous UV-C device.DESIGNProspective observational study.METHODSWe used 6 UV light sensors to determine UV-C irradiance (W/cm2) and UV-C dosage (µWsec/cm2) at various distances from and orientations relative to the UV-C device during 5-minute and 15-minute cycles in an ICU room and a surgical ward room. In both rooms, stainless-steel disks inoculated with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile spores were placed next to sensors, and UV-C dosages and log10 reductions of target organisms achieved during 5-minute and 15-minute cycles were determined. Mean irradiance and dosage readings were compared using ANOVA.RESULTSMean UV-C irradiance was nearly 1.0E-03 W/cm2 in direct sight at a distance of 1.3 m (4 ft) from the device but was 1.12E-05 W/cm2 on a horizontal surface in a shaded area 3.3 m (10 ft) from the device (P<.001). Mean UV-C dosages received by UV-C sensors located at different distances and orientation relative to the device varied significantly during 5-minute cycles and during 15-minute cycles (P<.001). Log10 reductions ranged from >4 to 1–3 for MRSA, >4 to 1–2 for VRE and >4 to 0 log10 for C. difficile spores, depending on the distance from, and orientation relative to, the device with 5-minute and 15-minute cycles.CONCLUSIONUV-C irradiance, dosage, and antimicrobial effect received from a mobile UV-C device varied substantially based on location in a room relative to the UV-C device.Infect Control Hosp Epidemiol 2016;37:667–672

Restriction endonuclease analysis (REA) was evaluated as an epidemiologic typing tool to distinguish Branhamella catarrhalis strains. Fourteen 0-lactamase-producing strains were collected over a 16-month period at a hospital where a nosocomial outbreak of this organism was previously documented by REA. REA produced 12 distinct patterns which correlated with epidemiologic data. Chromosomal REA appears to be a useful technique for distinguishing B. catarrhalis strains.

The in vitro antibacterial activity of BMS-284756 was compared to those of ciprofloxacin, gatifloxacin, moxifloxacin, ceftriaxone, imipenem, piperacillin-tazobactam, and amoxicillin-clavulanic acid against 492 gram-positive clinical isolates. BMS-284756 was the most-active agent against Streptococcus pneumoniae, Streptococcus viridans, beta-hemolytic streptococci, methicillin-sensitive and -resistant Staphylococcus aureus, methicillin-sensitive and -resistant coagulase-negative staphylococci, and enterococci.The fluoroquinolones have considerable antimicrobial activity against most gram-negative bacilli and cocci (15). However, ciprofloxacin and other early fluoroquinolones provide limited activity against most gram-positive organisms (1). The synthesis of newer fluoroquinolones has focused on overcoming the limitations of the early fluoroquinolones by expanding their spectrum of activity with regard to gram-positive organisms (2,5,8,9,13). Serious infections due to Streptococcus pneumoniae, viridans group streptococci, and enterococci have become major treatment problems because of their resistance to several, if not most, currently available antimicrobial agents (8,9,14).BMS-284756 is a novel des-fluoro(6) quinolone that differs from the fluoroquinolones in that it lacks a fluorine molecule at the C-6 position. BMS-284756 has a broad spectrum of antimicrobial activity, including activity against gram-positive bacteria (6, 10). A potential advantage of the des-fluoro(6) quinolone derivatives are that they show less acute toxicity in mice than the fluorinated quinolone compounds and may therefore have the potential of an improved toxicity profile in humans as well (K. Hayashi, Y. Todo, S. Hamamaoto, K. Ojima, M. Yamada, T. Kito, M. Takahata, Y. Watanabe, and H. Narita, Abstr. 37th Intersci. Conf. Antimicrob. Agents Chemother., abstr. F-158, 1997).In the present study, the in vitro activity of BMS-284756 was tested and compared to those of ciprofloxacin, gatifloxacin, moxifloxacin, ceftriaxone, imipenem, piperacillin-tazobactam, and amoxicillin-clavulanic acid against 492 gram-positive clinical isolates from Yale-New Haven Hospital. BMS-284756 E-test was obtained from Bristol-Myers Squibb, Princeton, N.J. The E-test strips for the other antibiotics were obtained from AB Biodisk North America Inc., Piscataway, N.J. All organisms were tested using the E-test methodology for susceptibility testing (4, 11). Specifically, 2 ml of tryptic soy broth was inoculated with organisms to a density of a 0.5 McFarland standard from a freshly grown subculture (grown overnight) and applied to a 150-mm-diameter MuellerHinton agar plate for testing of staphylococci and enterococci and to Mueller-Hinton agar supplemented with 5% sheep blood for testing of streptococci. E-test strips were applied following the manufacturer's recommendations. Staphylococci and enterococci were incubated at 37°C in an ambient air incubator, and streptococci were incubated in a 5% CO 2 incubator at 37°C. The plates were examined after 16 to 20 h of incu...