Fit testing is essential to match the N95 (DS2) filtering facepiece respirator with the individual face. However, a properly fitted respirator is relatively difficult to find for women under 40 years old, so structural improvement of the N95 filtering facepiece respirator is required. Almost all N95 filtering facepiece respirators are fixed to the head with only elastic straps. The present study examined if the fitting ratio could be improved for women under 40 years old with adjustable head straps passed around the neck and attached to the respirator near the mouth with a sweat-absorbent 3-D facepiece lip cushion. Twenty subjects wore two types of N95 filtering facepiece respirators, with the adjustable head straps around the neck and attached to the respirator near the mouth with the sweat-absorbent 3-D facepiece lip cushion, and with only elastic straps as a control. Participants were tested with a quantitative fit test using the Mask Fitting Tester Model MT-03TM (Shibata Kagaku Corporation). The permissible range of leakage rate was less than 5.0%. All participants achieved leakage rates of less than 5.0% with normal breathing for the N95 filtering facepiece respirators with the adjustable head straps near the mouth and the sweat-absorbent 3-D facepiece lip cushion. However, five participants had leakage rates over 5.0% with normal breathing using the N95 filtering facepiece respirators with elastic straps only. Three participants had leakage rates of 5.0% or more when bending over with the N95 filtering facepiece respirators with the adjustable head straps near the mouth and the sweat-absorbent 3-D facepiece lip cushion. However, 11 participants had leakage rates over 5.0% when bending over with the N95 filtering facepiece respirators with only rubber elastic straps. This study suggests that the N95 filtering facepiece respirators with the adjustable elastic head straps near the mouth and the sweat-absorbent 3-D facepiece lip cushion provide better fitting for women under 40 years old.
Catheter-related bloodstream infection (CR-BSI) is one of the most important of the various nosocomial infections, so the CDC in the United States recommends maximum barrier precautions (MBP). However, many neonatal intensive-care units (NICU) in Japan do not follow MBP, but the incidence of nosocomial infections is lower than in the United States. The incidence of CR-BSI over the past 5 years in our NICU, which does not follow MBP, was reviewed to discuss the necessity for following the CDC guidelines in Japan. Over a 5-year period from 2002 to 2006, percutaneously inserted central venous catheter (PICC) was inserted an average of 70 times in 55 patients per year. During the same period, the total number of catheterizations was 3652 days/5 years. According to the National Nosocominal Infection Surveillance (NNIS) data, the incidence of CR-BSI in children weighing <1000 g is high at 10.6/1000 catheter-days, but the incidence in our facility, including suspected cases, was very low at 0.81/1000 catheter-days. As a general rule, alcohol was used to sterilize the fingers without sterile gloves when inserting a PICC, and this did not result in CR-BSI in the clinical setting. Neonates soon after birth have no normal skin flora, and are in an aseptic state and immunologically immature. Precautions are in place to prevent infections, and neonates are cared for in closed incubators in the NICU, resulting in a low incidence of CR-BSI in Japan. Close examination of the current state of hospital-acquired infections in Japan and accumulation of more data is warranted before adopting anti-infection measures developed in Western countries with higher incidences of hospital-acquired infections.
Recently quick-drying antiseptics including 0.5 w/v% chlorhexidine gluconate/gel-alcohol (0.5%CHG-GA) have been sold in Japan. In this study, hand antiseptic effects and side effects of rough skin were compared with 0.2 w/v% benzalkonium chloride/liquid-alcohol (0.2%BAC-LA) which is the standard product. 0.5%CHG-GA had similar antiseptic effect to 0.2%BAC-LA immediately after hand antisepsis. 0.5%CHG-GA was superior to 0.2%BAC-LA during the 3 hours after hand antisepsis. There was no difference in the side effects of rough skin. Therefore, 0.5%CHG-GA is useful compared with 0.2%BAC-LA for prolonged hand antisepsis effects.
A total of 1,650 Escherichia coli, 659 Klebsiella spp., and 241 Proteus mirabilis strains were collected during a 3-month period (October-December 2006) at 32 institutes participating in the Shiga Prefecture infection control network to investigate the expression of extended-spectrum β-lactamases (ESBLs). ESBLs were detected in 55 (3.3%), 8 (1.2%), and 40 (16.6%) of the E. coli, Klebsiella spp., and P. mirabilis isolates, respectively, using the Clinical Laboratory Standards Institute Document M100-S16 and PCR analysis. Of the 55 ESBL-positive E. coli strains and 40 ESBL-positive P. mirabilis strains, 28 isolates carried the genes for CTX-M9 and 40 carried genes for CTX-M2 β-lactamases, respectively. Identical PCR fingerprint profiles were obtained by random amplified polymorphic DNA (RAPD) pattern analysis for E. coli from three separate institutes, suggesting nosocomial spread in these institutions. Moreover, P. mirabilis strains displaying identical PCR fingerprint profiles were identified from five institutes, suggesting nosocomial spread in Shiga Prefecture. Each medical facility completed a questionnaire survey, allowing us to examine infection control measures. According to the responses, the problems caused by ESBLs in facilities are understood by most facilities (29 facilities), and infection control measures were thus improved. The frequency of occurrence in the facilities and realities of ESBL diffusion in the Shiga Prefecture were clarified by this investigation. The study provided the opportunity to review the infection control measures in each facility and underlined the importance of monitoring antibiotic-resistant bacteria in the region.
Ralstonia pickettii with similar biochemical properties was isolated from clinical specimens of the content of the cervical canal from five outpatients of obstetrics in our hospital on June 23, 2006.The infection control team interviewed the link nurse of obstetrics on June 26. The common medical practice to all five patients was a bidet for vulva washing with a limited part washing device irrigator set up in the first inspection room. Bacterial culture of the 0.025% benzalkonium chloride solution that remained in the nozzle of the limited part washing device irrigator was performed. R. pickettii was identified with the same biochemical properties as the five bacterial strains isolated from the patients. The five bacterial strains derived from the patients and one bacterial strain derived from the antiseptic solution in the nozzle were analyzed by the random amplified polymorphic DNA polymerase chain reaction (RAPD) method, which strongly suggested that all were the same bacterial strain. Therefore, we supposed that the infection spread by indirect contact mediated by the 0.025% benzalkonium chloride antiseptic solution contaminated with R. pickettii in the nozzle of the bidet for vulva washing.
Vancomycin-resistant Enterococcus (VRE) was detected in a patient's feces for the first time at our hospital since surveillance of bacterial resistance was begun. The status of the patient, the treatment of the infection, and interventions to stop the spread of the infection were immediately assessed by the infection control team (ICT). Initial screening involved 115 specimens, including patients hospitalized with the VRE patient, physicians and staff members, and environmental specimens were examined. VRE was detected in two of these specimens. As a result of thorough environmental control, including hand washing and changing of gloves, VRE was not detected after the additional screening, and the spread of infection was prevented.
The reasons for agreement and disagreement with research on the safety of influenza pre-pandemic vaccination were investigated. Most staff (66.6%) strongly agreed with the effectiveness of vaccines for prevention against pandemics. The three highest-ranking reasons for agreement were as follows: ‘There will be no alternative method’, ‘There will be no other chance for vaccination’ and ‘It seemed effective’. Therefore, their expectations regarding the effectiveness of the vaccine and recognition of pandemic diseases seemed high. More physicians, nurses and paramedics than clerks and cooks agreed that vaccination is effective, because such staff are closer to patients. Half of the physicians, nurses, paramedics and clerks agreed that there will be no alternative method or vaccination seemed effective in contrast to cooks and other categories (cleaning staff, etc.), suggesting that recognition of vaccination differs with staff function. In conclusion, more educational intervention about vaccination is needed to increase knowledge because there was disagreement among the staff as indicated by the selection of the option ‘I expect that I would not be infected’ in all staff categories.
We investigated the use of carbapenems in our hospital between January 2005 and June 2008, and examined the trend of susceptibility to different antibacterial agents and cross-resistance using 813 strains of Pseudomonas aeruginosa isolated from in-patients. We conducted susceptibility tests to carbapenems on 38 strains isolated during a three-month period from November 2007, for comparison with the findings of nationwide surveillance. The amount of carbapenems used markedly increased by approximately 2 times in July-December 2007 (later half) compared to January-June 2007 (first half). From 2005 to 2007, annual changes in susceptibility were low, and the susceptibility rates were maintained at 90% or above for AMK, GM, CPFX, LVFX, PIPC and CFPM; and at 80% or above for IPM and MEPM. In 2008, the number of antibiotics with susceptibility rates of 90% or above was reduced to only three: AMK, GM and PIPC. These results suggested that increased use of carbapenems was related to decreases in susceptible bacteria. Comparison of the susceptibility rates to different antibacterial agents of 35 IPM-resistant strains and 27 MEPM-resistant strains isolated during a one-year period from July 2007 found that the susceptibility rates were low in MEPM-resistant strains. Comparison of the susceptibility results of strains isolated from November 2007 to January 2008 with the nationwaide surveillance data found that the MEPM-resistant rate was higher at 23.7%. Comparison of the resistance rates to carbapenems showed that the resistance rate to DRPM was the lowest at 22-33%. No metallo-beta-lactamase-producing and no multi-drug resistant P. aeruginosa strains were observed. Although the present study period was only for a short period of 3.5 years, the results indicated that increased use of carbapenems is associated with decreases in susceptibility rates; in particular MEPM-resistant strains showed decreased susceptibility to various antibacterial agents including carbapenems. In the future, survey of the trends of carbapenem use and surveillance of bacterial susceptibility should be continued to ensure correct use of carbapenems.