The efficacy of the 2005/2006 influenza season vaccine was assessed, which consisted of A/H1N1/New Caledonia/20/99, A/H3N2/New York/55/2004 and B/Shanghai/361/2002, in healthcare workers, by determining the hemagglutination-inhibition (HI) antibody titer against each vaccine strain. The seroprotection rates (ratio of subjects with a protective HI antibody titer of 40 or higher) of the 2004/2005 season vaccine employed against A/H1N1/New Caledonia, A/H3N2/New York, B/Shanghai and A/H3N2/Wyoming were 65.0%, 32.5%, 48.4% and 42.0%, respectively, before the vaccination, and increased to 92.2%, 95.7%, 76.6% and 86.5%, respectively, 4weeks after immunization. Significantly (p< 0.001) higher increases in antibody titer were observed in subjects without protective HI antibody than in subjects with protective HI antibody. The seroprotection rates against A/H1N1/New Caledonia, A/H3N2/New York, B/Shanghai and A/H3N2/Wyoming, were decreased to 89.6%, 88.1%, 70.1%, and 86.6%, respectively, at 16 weeks after vaccination, and then to 67.2%, 62.5%, 57.8% and 50.0%, respectively, at 1 year after vaccination. HI antibody titers against all strains except for A/H1N1/New Caledonia persisted at higher ratios at 1 year after vaccination than before vaccination. Of 11 subjects in the non-vaccinated group, none was diagnosed with influenza, yet 4 showed a 4-fold or more increase in antibody titer, indicating the presence of silent infection. Since no subject in the vaccinated group was diagnosed with influenza during this season, we were not able to assess the protective effect of the vaccination. Differences in antibody titers before vaccination were evident in the A/H3N2, Wyoming and New York strains, so annual vaccination is recommended.

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The clinical significance of pertussis infection is underestimated in Japan, so no infection control plan for nosocomial pertussis infection has been established. Our hospital experienced several episodes of nosocomial pertussis exposure, so an infection control plan for pertussis was developed according to the CDC guidelines including surveillance with classifying contacts and chemoprophylaxis. Here we describe our infection control plan and experience with infection control for exposed patients. In addition, the incidence of pertussis infection in adults was examined using agglutinating titers for pertussis in patients with chronic cough. The study found that 23% of patients had suspected pertussis infection. The clinical significance of nosocomial pertussis infection is important to recognize, and early diagnostic methods and criteria for the diagnosis of pertussis should be established to efficiently prevent nosocomial infection.

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Nationwide outbreaks of infectious gastroenteritis were caused by the norovirus in 2006 and 2007, so “the noro-phase” was devised based on the conditions of local epidemics, outbreak in patients in our hospital, and reinforcement of environmental hygiene and restrictions of the use of common facilities such toilets in the hospital. Furthermore, utilizing the “diarrhea surveillance” routinely performed on LAN for symptom surveillance in our hospital, we have developed a system to notify staff of a current “noro-phase” using the LAN so that every employee in the hospital can share common information about that particular phase. So far, the “noro-phase” procedure has worked quite well. In March 2007, when the norovirus epidemic terminated in this area, a total of only seven cases were observed in our hospital, including two mild cases with symptoms of diarrhea that disappeared within a day or two. We observed one patient in each of five wards, including one uncertain case of secondary infection without further evidence. Therefore, our system appears robust enough to deal with any GI epidemic such as norovirus.

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This study was designed to compare antimicrobial use and cost, and outcome for pediatric patients with infection before and after implementation of the antimicrobial use notification policy or initiation of intervention by the infection control team (ICT) in our hospital. The policy was applied in October 2004, requiring the use of “special drugs” defined as anti-MRSA agents, fourthgeneration cephalosporins, carbapenems and broad-spectrum penicillin was notified to the infection control committee. Total antimicrobial use decreased by 15% (p<0.05) after policy implementation. The use of “special drugs” tended to decrease. In particular, use of fourth-generation cephalosporins significantly decreased by 85% (p<0.05), and use of anti-MRSA agents significantly decreased by 20% (p<0.01). Total antimicrobial expenditures decreased by 20%. In August 2005, we started ICT intervention for use of “special drugs”. To evaluate the effects of implementation of both the notification policy and ICT intervention, a retrospective assessment of a tenmonth time period of only policy implementation and a ten-month time period of both policy and ICT intervention implementation was performed. No significant change occurred in the use of anti-MRSA agents, carbapenems and second-generation cephalosporins during the policy only period, but the use of these agents decreased significantly (p<0.05) when the intervention by ICT was started. Comparing 2004 (a transition year) and 2006 (after full implementation of both programs), infection-related hospital mortality in pediatric patients in the intensive care unit decreased notably from 20% to 0%. Implementation of both antimicrobial use notification policy and ICT intervention resulted in substantial reductions in antimicrobial use and cost, and infectionrelated hospital mortality in the maternity center and children's hospital.

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Fungal exposure is difficult to avoid as spores are present in ordinary indoor dust and easily enter a ward. In our dental hospital, molds of environmental origin colonized damp/water-damaged building materials. Mold formation was mainly observed on/in walls on the north side of buildings. Stachybotrys chartarum, Chaetomium funicola and Aspergillus niger were isolated from these sites. Better design, careful construction and renovation, and diligent operation and maintenance of a hospital may minimize the exposure of humans to molds.

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Objectives: To determine the validity of screening criteria based on signs and symptoms for catheter-associated bacteriuria in elderly hospitalized patients. Design: Prospective observational study. Patients: Adult catheterized patients ≥65 years of age in two units of a general hospital. Methods: The following data were collected between August and October 2004;signs and sym-Atoms of urinary tract infections, dipstick tests and urine cultures once a week. Detection of any type of microorganisms of more than 10⁵ CFU/mL was used to calculate sensitivity, specificity, positive/negative predictive value and efficiency. Results: Forty-four subjects (mean age 81 yearold) were enrolled. The sensitivity of signs and symptoms of at least one of the following was 65%; fever ≥37.5°C, urgency/frequency/dysuria/suprapubic tenderness and pyuria. Therefore, using of only signs and symptoms will miss 1/30f cases of bacteuria. In contrast, the sensitivity of leukocyte esterase and nitrate by the dipstick test was over 90%, and efficiency was 78%. Conclusions: The validity of the dipstick test was higher than the screening criteria based on signs and symptoms for early detection of UTIs in the elderly.

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To evaluate the performance of the squeezed sponge-mop (S-mop) produced from cellulose fibers, the capture efficiency of three different types of imitation dust and the correlation between bacterial growth and water retention were compared to those of shaggy mops such as the Flat mop and Kentucky mop. The squeezed S-mop removed almost all purified talcum powder, cream and paper powder from a desk. The water retention of the squeezed S-mop kept in indoors at less than 70% of humidity was small, so growth of bacteria remained at a low level. As a result, the mop spread few bacteria on the floor surface during the following sweeping. Use of the set of the special squeezer and the S-mop, which provide high capture efficiency of dust and are easily dried, is effective to protect immunocompromised patients from some environmental agents.

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Saitama City Government is enforcing countermeasures to eradicate measles, including the spread of accurate information and education, vaccination for all preschool children, and surveillance of all incidence cases. An outbreak of measles has occurred in Saitama City since April, 2007. This study analyzed reported cases of measles; and assessed the first outbreak of measles in Saitama City. All cases reported in the 14^th week (April 2 to 8) and the 27^th week (July 2 to 8) were included. A total of 422 cases were reported. The peak week was the 22nd (63 cases). Of all subjects, 142 had been vaccinated, 187 had not been vaccinated, and 93 were unknown. According to the age distribution, 31% of all cases were concentrated at the age of 15-19 years. All subjects less than 12 months of age and 41% aged 15-19 years had not been vaccinated. Our results suggest that thorough implementation of routine vaccination and reconsideration of target subjects for vaccination are essential for the eradication of measles in Japan.

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[in Japanese]

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Multidrug-resistant organisms may emerge as a result of many factors including widespread or long-term usage of broad-spectrum antimicrobials.Therefore, it is essential to avoid inappropriate use. A carbapenem use restriction program was developed to promote correct antimicrobial use. As a result, the consumption of carbapenems significantly decreased from 12, 993 vials in 2005 to 4, 815 vials in 2006 (p<0.01). Moreover, the incidence of Pseudornonas aeruginosa isolates resistant to imipenem (IPM) and the detection rate of multidrug-resistant P. aeruginosa significantly decreased from 12.5% to 6.6% (p<0.05) and from 3.0% to 1.3%, respectively. Thus, the restriction program prevented the unnecessary use and optimized the administration of carbapenems, and successfully reduced the emergence of drug resistant bacteria. Administration of the most effective dosage (based on the PK/PD properties of carbapenems) of 2 vials two times a day or 1 vial three times a day was increased. The restriction program was effective in terms of correct antimicrobial use. Infectious disease consultation should be mandatory prior to prescription of broad-spectrum antimicrobials.

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[in Japanese]

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To prevent nosocomial infection in a community, detailed information is required about any nosocomial infections that might have occurred in the community. With such information infection control measures can be improved and maintained. A questionnaire was sent out to 265 hospitals with 20 or more beds affiliated to the Kagoshima Medical Association. The questionnaire asked the director and/or the chief of the infection control team (ICT) of the hospital about preventive measures against nosocomial infection and occupational exposures to infections or needle stick injuries. Of 265, 132 hospitals (50%) responded to the questionnaire. One problem in Kagoshima Prefecture is the low number hospitals with ICTs (only 58%), as well the absence of an ICT in 28% of the hospitals with 200 or more beds. There were also significant differences between hospitals in the rates of introduction of preventive measures against nosocomial infection and occupational exposures. The rates of introduction of some measures were lower in Kagoshima Prefecture than reported previously. ICT networks, medical associations and societies, local authorities, and the government should assist hospitals to prevent nosocomial infections in their community.

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[in Japanese]

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