We examined the relationship between the distribution of Legionella bacteria and various physicochemical characteristics of hot springs in Japan. Legionella bacteria were isolated from 52 (49.5%) out of 105 water samples, particularly from outdoor hot springs (67.3%). The bacterial count in the water samples positive for Legionella (86.5%) ranged from 10¹ to<10³ cfu/100mL. L. pneumophila serogroup (SG) 4 (27.8%) was predominant in the water samples, folowed by SG 5 (12.2%). The pulsefield gel electrophoresis (PFGE) patterns of chromosomal DNA for L. pneumophila SG 4 isolated from different parts of a hot spring resort were identical. Isolation of Legionella species from hot spring waters did not occur at pH 1.8-3.3, SO₄^2-: >780mg/L, and H₂SiO₃: >146mg/L. The hot waterrecirculating systems were applied to 18 out of 20 (90%) hot spring facilities which were found positive for Legionella. These results indicate that Legionella species are widespread in hot springs throughout Japan, except for waters with a low pH and non-recirculating waters, and that a single strain of L. pneumophila SG 4 is predominant in a particular hot spring resort.

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At present, in Japan, hepatitis B virus (HBV) and hepatitis C virus (HCV) infection by blood transfusion rarely happens. However, according to the national survey, outbreak of sporadic acute hepatitis B and C is reported every year and viral hepatitis induced by iatrogenic infection is also reported. We think that education and enlightenmen for measures of infection control for hepatitis virus in dentisal medical care are important. Therefore, we carried out a questionnaire survey about measures of an infection control including hepatitis B and C for 352 students of a certain faculty of dentistry and a dental hygienist school. 35.5% of the total students thought the defense of oneself against infection was more important than defense of cross infection. Furthermore, the prevalence of the student who thought to permit recycle of a disposer glove and a disposer cartridge of a local anesthesia was 13.1% (46/352), 14.8% (52/352), respectively. The prevalence of students who recognized that HCV and HBV were detected from not only blood but also body fluid such as saliva remained in 65.3%. Consequently, the reality that knowledge of hepatitis virus and understanding about sterilization and disinfection of instruments were low became clear.
In conclusion, immediate making of the guideline that aimed at standardization of prevention of hospital infection in domestic dental treatment and education to introduce the curriculum with a high regard for risk management of infection for students of dentistry will be required. In addition, it is an important problem to spread thoughts of standard precautions for dentistry.

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We analyzed the performance of (1, 3)-Beta-D-glucan (measurement by the alkaline-kinetic chromogenic Limulus method [FUNGITEC G test-MK, Fungitec] and the kinetic turbidimetric Limulus method [Beta-Glucan test WAKO, Wako]) and we carried out Aspergillus galactomannan antigen detection (enzyme-linked immunosorbent assay, ELISA test) for the early diagnosis of invasive aspergillosis in patients with hematological diseases at the time of febrile episodes of unknown origin that did not respond to antibacterial therapy for more than 3 days. During a one-year period (April 2002 to March 2003), a total of 69 febrile episodes in 58 patients were studied; 8 cases of invasive aspergillosis were diagnosed according to the definition of the European Organization for Research and Treatment of Cancer/Mycosis Study Group, and 61 cases were found to be non-mycotic diseases. Based on the analysis of 69 results with confirmed disease status, the overall performance of the Fungitec, the Wako, and the ELISA test were as follows: sensitivity was 0.88, 0.63, and 0.50, respectively, whereas the specificity was 0.85, 0.98, and 1.0, respectively. Moreover, there was a strong relationship between the log-transformed values of the (1, 3)-Beta-D-glucan levels measured by the two methods (r=0.92 [95%CI, 0.89-0.94]; p<0.001). For the statistical analysis of these serological tests a receiver operating characteristic curve (ROC) was used, as well as the resulting area under the ROC curve (ROC AUC). The ROC AUC and the cut-off values that gave the highest accuracy were as follows: 0.92, 24.9pg/ml for the Fungitec, 0.84, 7.3pg/ml for the Wako, and 0.89, 0.9 COI for the ELISA test, respectively.
In conclusion, these results indicate that both of the two (1, 3)-Beta-D-glucan measurement approaches served equally well as surveillance tools for determining the extent of invasive aspergillosis; in addition, the log-transformed value of these tests can be used for comparison. Moreover, the ELISA test was found to have clinical utility, both as a surveillance and as a diagnostic tool when invasive aspergillosis was suspected. It should be noted that the galactomannan assay had sensitivityrelated limitations; lowering the cut-off value is expected to increase the diagnostic value for use in cases of invasive aspergillosis.

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Bartonella henselae is a causative agent of cat scratch disease. We preliminarily tested four media for the bacterial growth, including agar plates with sheep, horse or rabbit blood, and chocolate agar. Of these media, rabbit blood and chocolate agar plate were found to be more excellent for the growth than the medium with sheep or horse blood.
Blood samples from 60 domestic cats in Yamaguchi Prefecture were then cultured using 7% rabbit blood agar plates and BACTEC9050 (BD), automated blood culture microbial detection system. B. henselae was isolated from six of the 60 (10%) blood samples. Tiny colonies of B. henselae were visible on the agar medium after one week of culture at 35°C in the 5% CO₂ atmosphere. BACTEC 9050 detected B. henselae in one of the 10 blood samples and it took two weeks to detect the bacteria automatically, though gram stain failed to show organisms in the blood culture bottle.
In conclusion, rabbit blood or chocolate agar and incubation of agar media more than one week and of BACTEC more than two weeks are recommended for the detection of B. henselae.

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We performed epidemiologic study of 109 strains of methicillin resistant Staphylococcus aureus (MRSA) which were detected in our hospital.
Of these strains, 6 strains showed resistant to Teicoplanin (TEIC) which MIC level were between 4 to 8μg/mL. All of them showed some phenotype, such as type II of coagulase, type A of enterotoxin, and were producing TSST-1.
Genotype analysis by PFGE also showed that those strains ware identical. From analyzing the spreading rout of these TEIC resistant MRSA, we speculate that they first were in ICU ward, then spread all over the hospital carried by the stuff cross-working ICU and other units of hospital.

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Fluorescent lamp that is coated with a photocatalyst film, titanium dioxide (TiO₂), can catalyze the microorganisms and smell producing molecules that touch the membrane. In this report, we examined the effect of this coated lamp by the number of floating microorganisms or smell molecules in a room installed with this lamp. The number of floating microorganisms was examined independently in different laboratories before and after installing the lamps in an animal facility and a vegetable processing room of a food company. We found that the number of floating microorganisms was significantly reduced after the installation of this coated lamp. To test for smell molecules, acetaldehyde was injected into a closed chamber installed with the coated lamp and the result was compared to a control where a regular fluorescent lamp was used. The acetaldehyde concentration did not change with the regular lamp but was halved after 1h with the photocatalyst coated lamp. To test the effect in real settings, questionnaires were filled out by restroom users in several different places. About 90% of those surveyed answered that there was a reduction of smell after the installation of the photocatalyst coated lamp. We concluded that the installation of this coated fluorescent lamp reduced not only the floating microorganisms but the smell in various practical situations.

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Weevaluated the performance of an improved version of Espline Influenza A & B-N (Fujirebio Inc., Japan), an immunochromatography test using enzyme immunoassay for rapid diagnosis of influenza A and B. The test produced positive results for four strains of influenza viruses and thirty-one influenza viral antigens and negative results for all of thirty strains of other respiratory viruses that were tested. The detection limit of this test was 5.8× 10² to 5.8×10³ pfu/assay, which is more sensitive than the old version of Espline. Furthermore, 715 respiratory specimens collected from the patients (children, 79.4%; adults, 18.5%; unknown, 2.1%) with influenza-like illnesses during the 2002/2003 influenza season in Japan were tested as part of a clinical evaluation of this test. The relative performance of this test compared to cell culture and nested RT-PCR results were examined. In the cell cultures, influenza viruses were detected in 488 of the 715 specimens (overall, 68.3%; AH3, 41.7%; B, 26.4%; AH3 and B, 0.1%). For influenza A, the sensitivity of this test was 95.4% (125/131) for nasal aspirates, 96.8% (92/95) for nasal swabs, and 85.1% (63/74) for throat swabs. For influenza B, the sensitivity of this test was 91.2% (52/57) for nasal aspirates, 88.1% (59/67) for nasal swabs, and 71.6% (48/67) for throat swabs. The new test exhibited a remarkably higher sensitivity to influenza A in throat swabs than the old version of Espline. Only two false positive results were obtained out of a total of 223 virus negative specimens; the specificity of the test was 100% (88/88) for nasal aspirates, 97.6% (81/83) for nasal swabs, and 100% (52/52) for throat swabs. We conclude that the new Espline Influenza A & B-N rapid diagnostic test is easy to use and has a high sensitivity and specificity, especially for influenza A.

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Haemophilus influenzae type b (Hib) is the most frequent pathogen of bacterial meningitis in Japanese children. The prevalence of beta-lactamase-negative ampicillin-resistant (BLNAR) Hib strain has been increasing in recent years. Furthermore, antibiotic activities of cefotaxime (CTX) and ceftriaxone (CTRX) have decreased against some of those BLNAR strains. We report a case of one-year-old boy who suffered from meningitis caused by BLNAR Hib. The MICs of CTX and CTRX for the strain isolated from cerebrospinal fluid was 1.0 and 0.5μg/ml, respectively. The patient was administered high-dose CTRX (150mg/kg/day) and recovered completely without any sequela. The highdose CTRX administration may be a considerable choice of the treatment of BLNAR meningitis.

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[in Japanese]

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