In the US, antiseptics with an indication of “preoperative skin preparation” are evaluated according to the tentative final monograph issued by the FDA (FDA-TFM). In the FDA-TFM, antiseptics are required to reduce the number of resident bacteria to 2.0 log₁₀ CFU/cm² on an abdomen test site and to 3.0 log₁₀ CFU/cm² on a groin test site 10 minutes after application of the antiseptic to the test sites, in subjects who are instructed to avoid the use of antimicrobials (systemic or topical) and exclusively use non-antimicrobial personal care products for the acclimation period of more than 2 weeks before testing. For the evaluation using the FDA-TFM, study subjects are required to have sufficient numbers of resident bacteria before treatment as the baseline bacterial counts. However, whether the number of bacteria may sufficiently increase in Japanese people under these acclimation conditions is unknown. In this study, total number of resident bacteria and number of five bacteria genera, including typical resident bacteria genera, were measured on both abdomen and groin test sites in Japanese subjects who were acclimated according to the FDA-TFM. The number of bacteria on the abdomen site did not increase sufficiently in the subjects, suggesting that an adequate number of study subjects who have appropriate baseline bacterial counts on the abdomen is difficult to secure. On the other hand, the number of bacteria on the groin site significantly increased, suggesting that a sufficient number of study subjects with appropriate baseline bacterial counts on the groin can be secured. The resident bacterial flora was not altered by the acclimation conditions employed in this study. According to the FDA-TFM, efficacy evaluation of novel antiseptics is considered to be possible by measuring the reduction of bacterial counts even in the Japanese population, although an adequate number of study subjects who have appropriate baseline bacterial counts on the abdomen may be difficult to secure.

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  Measles and rubella vaccines were given to health care workers of Hokkaido University Hospital with inadequate antibody levels for prevention of measles and rubella: anti-measles antibody levels less than 1:128 determined by the gelatin particle agglutination (PA) method, and anti-rubella antibody levels less than 1:16 determined by the hemagglutinin inhibition (HI) method. After measles vaccination, 92 (74.8%) of the 123 health care workers acquired anti-measles antibody levels higher than 1:128, and 70 (56.9%) acquired anti-measles antibody levels higher than 1:256. After rubella vaccination, 118 (90.8%) of the 130 health care workers acquired anti-rubella antibody levels higher than 1:16, and 101 (77.7%) of them acquired anti-rubella antibody levels higher than 1:32. The seroconversion rates following single doses of measles and rubella vaccines to infants are higher than 95%. However, the acquisition rates of antibodies sufficient for prevention of measles and rubella following single doses of measles and rubella vaccines to health care workers were less than 95%.

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  For screening of contact infection with tubercle bacillus, the interferon-γ release assay is recommended. However, this procedure is not commonly used in tuberculosis ward-free hospitals, and its application varies. In our hospital, QFT was introduced for contact infection screening, and applied using an algorithm. Contact infection screening was performed in cases of pulmonary tuberculosis with a positive reaction on a smear test, in the absence of a strategy to prevent air infection. An exposure test (baseline examination) was carried out within 2 weeks after exposure. An additional QFT was conducted 8 to 12 weeks after exposure (post-exposure examination). In patients who had not undergone baseline examination, with a post-exposure interval of 2 weeks or more, only post-exposure examination was performed. If the results of post-exposure examination were difficult/impossible to evaluate, an additional QFT was conducted after 4 to 8 weeks (additional post-exposure examination). In 23 cases, screening involving 434 persons, consisting of health care professionals, students, and patients staying in the same room, was performed. In 5 (1.4%) of 215 persons with a negative reaction on baseline examination, post-exposure examination revealed a positive reaction. In 9 (4.2%) of these 215 persons, the results of post-exposure examination were difficult to evaluate. On additional post-exposure examination, 2 of 10 persons showed positive reaction. In cases in which only post-exposure examination was performed, 9 (5.8%) of 159 persons showed a positive reaction, and evaluation was difficult in 18 (11.3%) of 159 persons. On additional examination involving 15 in whom evaluation was difficult, 2 (13.3%) showed a positive reaction. The introduction of QFT facilitated clarification of the presence or absence of infection, contributing to the prevention of hospital infection with tubercle bacillus. In cases in which only post-exposure examination was performed, it was unclear whether or not infection was related to exposure immediately before the examination. QFT must be introduced for admission screening.

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  Among the episodes of blood and body fluid exposure, exposure of the eyes is comparable to needle-stick accident in risk for infection. To clarify exposure of the eyes and periphery, we investigated the occupation of exposed persons, exposed substances, and place of exposure over the past 2 years and 6 months in Tohoku University Hospital, which contains both Medical and Dental Schools. A total of 41 episodes were reported involving exposure of the eyes and periphery. The 41 persons consisted of 19 nurses, 9 physicians, 4 medical students, 3 midwives, 2 dentists, and 2 clinical engineering technologists. Substances involved in these exposures included blood in 14 episodes, body fluid in 7, sputum in 4, and injection in 2. The places of exposure consisted of the operating room in 14 episodes, ward in 10, intensive care unit (ICU) in 4, Emergency Department in 3, dialysis treatment room in 3, delivery room in 2, and blood collection room in 2. In particular, the number of delivery-related episodes was large (n=6). Furthermore, the total number of exposure episodes was 67. Of these, 41 (61.2%) involved the exposure of the eyes and periphery. In Tohoku University Hospital, such exposure was most frequent in the operating room, suggesting that staff working in the operating room must wear goggles.

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  Isolation background of extended spectrum β-lactamase (ESBL) producers obtained from patient samples in Showa University Fujigaoka Hospital between 2003 and 2007, which is located in the northern area of Yokohama city in Japan, was investigated. Isolation number of ESBL producers was four in 2003, but increased to 29 in 2007. Eighty percent of all producers in 2007 were Proteus mirabilis and Escherichia coli. After these ESBL producers were pulsotyped, isolation backgrounds were retrospectively investigated in more detail. Of 11 P. mirabilis isolates in the CTX-M2 β-lactamase group, five with pulsotype A of the five different pulsotypes were obtained from inside-hospital occurrence in one, outside-hospital (cooperative hospital) occurrence in two, and unknown in two, respectively. However, none of the ten E. coli isolates with seven different pulsotypes were found from inside-hospital occurrence. These findings confirmed that a clonal CTX-M2 β-lactamase producer is present in patients utilizing cooperative hospitals, recognizing the necessity of active surveillance culture for assessing the ESBL producers carried by patients from cooperative hospitals.

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  The attendance of in-hospital study sessions is low among healthcare professionals, so knowledge regarding the prevention of infection may be deficient. However, in-hospital infection prevention and medical safety requires that healthcare professionals possess adequate knowledge regarding infection. Therefore, to ensure that healthcare professionals possess basic knowledge regarding infections, we planned several study sessions intended for all medical professions, which were held frequently, unlike aggregative training, by pharmacists from the ICT for each department. because of the frequent sessions and the cooperation of departmental leaders, the attendance rate of the in-hospital study sessions escalated to 95%, and the educational content of the study session could also be customized for each department. To verify the effectiveness of the study, we adopted the nominative confirmation test for the study session and attempted to review and discuss the educational influence of the session after the confirmation test was adopted by conducting a retest after one year. The accuracy rate of the confirmation test differed depending on the category of the job and question, but the effectiveness of the study session was 88.2% after the study session, compared to 66.8% before the study session in terms of the accuracy rate after the confirmation test was employed. Moreover, the confirmation tests with the same questions after one year showed an accuracy rate of 81.6%, which was higher than that calculated before the study session in the previous year, so seemed to achieve retention of knowledge. We concluded that the study session adopting the confirmation test for healthcare professionals provided more effective education.

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Background: Some employees engaged in central services in a hospital have experienced irritation to the eyes and throat near the hydrogen peroxide (HP) steriliser.
Method: The concentrations of hydrogen peroxide vapour (HPV) in the proximity of HP sterilisers (low-temperature hydrogen peroxide gas plasma steriliser: Sterrad NX^®, Sterrad 100S^®, and Sterrad 200^®, Johnson & Johnson, and Low-temperature vaporized hydrogen peroxide steriliser: Amsco V-PRO1^®, Sakura Seiki) were measured with an electrochemical detector.
Results: HPV was present at higher concentrations than anticipated.
Conclusion: Adequate air conditioning, donning gloves for bag handling, supplied-air respirator use for door opening, and other measures for the security of healthcare personnel should be seriously reevaluated.

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  To prevent infection and dissemination of drug-resistant bacteria as the main causes of contact infection in medical institutions, the improvement and maintenance of hand hygiene compliance are important. However, there are no established parameters for the evaluation of such compliance. We used the rates of consumption of alcohol-based hand disinfectants and hand cleaning agents as indirect parameters of hand hygiene compliance, and compared the MRSA detection and isolation rates in inpatients during 24-month periods before and after the intensification of a hand hygiene promotion project (April 2007). Significant increases (p<0.01) were observed in the mean consumption of hand disinfectants from 2.93±0.84 to 8.58±2.93 (L/1,000 patient days) and that of hand cleaning agents from 2.88±1.04 to 5.09±1.20 (L/1,000 patient days). Although there was no significant difference in the frequency of MRSA detection between the groups, the isolation rate significantly decreased (p<0.01) from 12.6±2.5 to 10.4±1.5%. Frequent interventions to promote hand hygiene employing various approaches may be effective for improving and maintaining hand hygiene compliance.

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  We report two cases of prolonged norovirus shedding for more than 3 months in severely immunocompromised HIV-infected patients. One of the patients had persistent diarrhea throughout his hospital stay and nosocomical transmission took place in the ward. Patients with leukemia, lymphoma or primary immunodeficiency, and patients taking immunosuppressive therapy have also been reported to develop chronic norovirus infection resulting in nosocomical infection. Our cases demonstrate that immunocompromised patients can suffer prolonged periods of norovirus infection for months, so we must take appropriate durations of infection control measures.

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