The entire coding region of the nucleoprotein (N) gene of Takamen and Komatsugawa strains of rabies virus isolated in Japan in 1940's were determined. Phylogenetic analysis was performed on 140 lyssaviruses (128 viruses of genotype 1 and 12 lyssaviruses of other genotypes) isolated in various parts of the world, including the two Japanese rabies strains, based on the sequences of 1, 350 nucleotides of the N gene. The rabies viruses were divided into 12 distinct clusters at least, reflecting geographical areas and hosts as reservoirs. The Takamen, Nishigahara, and RC-HL strains derived from the Nishigahara strain were grouped into the same cluster as the Chinese strain (3aG) in the worldwide distribution group. The Komatsugawa strain was grouped into the same cluster as the viruses from a raccoon dog from Khabarovsk, and from a steppe fox in area of Lake Baikal in Russia in a group consisting of Canada, Greenland, and the Arctic. These data along with the historical evidence suggest that Japanese rabies viruses, the Takamen and Komatsugawa strains, belong to two different clusters and moved into Japan from China and Russia, respectively.

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Bacterial interactions such as methicillin-resistant Staphylococcus aureus (MRSA) growth inhibition or inactivation of anti-MRSA antibiotics by Pseudomonas aeruginosa as an indirect pathogen were tested by in vitro assay.
Paired strains, P.aeruginosa and MRSA, used in this experiment were isolated from 63 respiratory samples at Juntendo University Hospital from 2002 to 2003. Growth inhibitory activities against MRSA by P.aeruginosa were tested with reversed agar plate method. Inactivation of anti-MRSA antibiotics by P.aeruginosa were assayed with disk diffusion method using agar over lay technique.
Fifty-six (88.9%) out of 63 samples showed the significant MRSA growth inhibitory activity by co-existed P.aeruginosa. Anti-MRSA antibiotics such as trimetoprim-sulfamethoxazole combination (ST), arbekacin (ABK) and minocycline (MINO) except Vancomycin (VCM) and Teicoplanin (TEIC) were inactivated by the co-existed P.aeruginosa.
Our data suggests that P.aeruginosa may play not only as a chronic respiratory pathogen but also as an indirect pathogen. Further, the most P.aeruginosa with anti-MRSA activity isolated respiratory sample may play as a modulator of MRSA infection.

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In the patient with a chronic respiratory disease, both Pseudomonas aerugiosa and methicillinresistant Staphylococcus aureus (MRSA) are frequently detected from expectoration. Vancomycin (VCM) and arbekacin (ABK) are both recommended for the chemotherapy of MRSA infection in Japan. Minocycline (MINO) is also selected for the treatment of MRSA infection. While rifampicin (RFP) and a trimetoprim-sulfamethoxazole combination (ST) are also recommended in Europe and USA but not recommended in Japan for the chemotherapy of MRSA infection.
It is pointed out that coexistence bacteria affect chemotherapy as an indirect pathogen. Not only an antibacterial action but the immunological action or the metabolic effect against Chronic P. aeruginosa infection such as DPB is known by the administration of 14-membered ring macrolides including erythromycin (EM).
We considered the influence of P. aeruginosa isolated with MRSA on the activity against anti-MRSA agents by the disk diffusion method with bilayer flat agar in uitro. Moreover, we also examined the influence of EM against the activity of the anti-MRSA agents when P. aeruginosa was coexistence.
One strain of MRSA as an indicator strain and 100 strains of P. aeruginosa as test strains, which were obtained from clinical materials, were used for the following experiment. P. aeruginosa was streaked on to the Mueller-Hinton agar culture medium (MHA), and they incubated at 35°'C for 24 hours. Then, the blood agar plate was piled up, MRSA was streaked on the blood agar surface, the susceptibility test disks (VCM, ABK, MINO, RFP, ST) were put on it, and incubated at 35°C for a further 24 hours. The diameter of the zone of inhibition around the susceptibility disks against MRSA was measured and compared with P. aeruginosa free experiments.
The anti-MRSA activity of MINO, ST and ABK was reduced by coexistence of P. aeruginosa. In RFP and VCM, the anti-MRSA activity was reinforced by coexistence of P. aeruginosa. Although the anti-MRSA activity of ST and ABK has improved by EM addition in the MHA plates, the anti-MRSA activity has not improved in MINO.
These results are suggesting that in a MRSA infection, the chemotherapy by anti-MRSA agents were affected by coexistence of P. aeruginosa as an indirect pathogen. The macrolides such as EM may be useful as a modulator for chemotherapy by ST or ABK when MRSA and P. ansuginosa are isolated at the same time from the patient.

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A total of 535 Haemophilus influenzae strains from 226 Japanese institutions participating in the Nationwide Surveillance Study Group for Bacterial Meningitis were sent to our laboratory during 1999 to 2003. All strains were analyzed by PCR to identify the β-lactam resistance genes, and their susceptibilities to β-lactam agents were determined. These strains wereclassified into 6 genotype patterns and MIC₉₀ values for ampicillin (ABPC): (i) β-lactamase nonproducing, ABPC susceptible (BLNAS) strains and lacked all resistance genes (27.7% of isolates; MIC₉₀, 0.5μg/ml); (ii) β-lactamase producing, ABPC resistant (BLPAR) strains (129%, 16μg/ml); (iii) β-lactamase nonproducing, ABPC resistant (Low-BLNAR) strains with a Asn 526 Lys amino acid substitution in ftsI gene encoding PBP3 (31.2%, 2μg/ml); (iv) β-lactamase nonproducing, ABPC resistant (BLNAR) strains with Ser 385 Thr and Asn 526 Lys substitutions in ftsI (172%, 8μg/ml); (v) amoxicillin/clavlanic acid resistant (BLPACR I) strains, having β-lactamase gene and a Asn 526 Lys amino acid substitution in ftsI (9.2%, 32μg/ml); and (vi) amoxicillin/clavlanic acid resistant (BLPACR II), having β-lactamase gene and ftsI substitutions as for BLNAR strains (19%, 64μg/ml). All but 4 strains were serotype b.
The prevalence of BLNAR strains has increased exponentially: 0% (n=0/41) in 1999, 5.8% (n=4/69) in 2000, 14.1% (n=19/139) in 2001, 20.1% (n=32/159) in 2002 and 29.1% (n=37/127) in 2003. The MIC₉₀s of BLNAR isolates except for ABPC were as follows: piperacillin, 0.125μg/ml; ceftriaxone, 0.25μg/ml; meropenem, 0.5μg/ml; cefotaxime, 1μg/ml; panipenem, 2μg/ml; cefozopran, 16μg/ml; and cefotiam, 64μg/ml.
To prevent such resistance from the increasing, expedited vaccination, correctidentification of the BLNAR by molecularly, and the proper selection of proper antibiotics based on PK/PD must be taken.

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To determine a more timely acquisition of accurate results for influenza patients, a rapid diagnostic testing for influenza were studied on 877 pediatric patients performed during the 2002-2003 flu season in our hospital. Of these, 337 patients were finally diagnosed as influenza based on the test results and treated with antiviral agents, amantadine or oseltamivir. Ten (29%) of the 34 patients whose tests were negative within 12 hours after onset became positive over 12 hours after onset. On the other hands, diagnoses based on antigen tests over 12 hours after onset were reliable because all 13 patients first confirmed negative were unchanged when tested afterward. These 10 patients missed the opportunity to take antivirals early, which possibly caused them to have significantly longer (p=0.0003) febrile duration and higher frequency of admission (p<0.0001) than the 106 patients first confirmed positive within 12 hours after onset. Days from onset until starting antivirals (mean 1.4 days), the febrile duration (mean 2.7 days) and frequency of hospitalization (20.5%) of the 219 patients who tested positive over 12 hours after onset were significantly worse (p<0.0001, p<0.0001 and p=0.0406, respectively) than those of patients testing positive within 12 hours after onset (mean 0.2 days, mean 1.7 days and 11.3%, respectively). The febrile duration (mean 2.3days) of the patients confirmed positive even over 12 hours, but within 48 hours, of onset was tolerable but significantly longer (p<0.0001) than that of patients confirmed positive within 12 hours after onset. The frequency (19.6%) of hospitalization of the patients confirmed positive even over 12 hours, but within 48 hours, of onset was not significantly different from that of patients confirmed positive within 12 hours after onset. These results suggested that over 12 hours but within 48 hours after onset of illness is the best period for the rapid diagnosis to correctly determine whether a patient should be treated with antiviral agents based on the result.

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Methicilin-Resistant Staphylococcus aureus (MRSA) strains with the exception of urinary strains were isolated from the inpatients in urology ward hospitalized in 2003 and medical workers. Biotype according to the production of coagulase, enterotoxin and mupirocin sensitivity, and genotype by pulsed field gel electrophoresis (PFGE), and clinical background were determined for the MRSA strains to analyze the transmission route of the infection.
In 34 medical workers in urology ward, MRSA were isolated in 6 (17.6%) workers from the nasal cavity, and the rate of colonization in doctors was higher than in nurses. Furthermore, mupirocinresistant strains were isolated from two medical workers. 18 MRSA strains were isolated in 2003 and the accounting was 8 strains from wounds, 6 strains from sputum or nasal cavity, 3 strains from blood, and 2 strains from urinary tract. Most of the patients with MRSA had operations undergeneral anesthesia or were under severe conditions with malignant tumors. No MRSA was detected at the same time from the same rooms. There were some rooms in which the MRSA detected rate was high, however no MRSA was isolated from hospital environments and dumping bacteria.
These results suggest that the involvement of the medical workers and the spread of MRSA in the society might be important as infection source and for transmission of MRSA in hospital.

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We evaluated a flow-through immunoassay for rapid detection of influenza A and B viral antigens, RapidTesta FLU AB (Daiichi Pure Chemicals Co., Ltd., Tokyo, Japan), by using 507 specimens collected from patients with influenza-like symptoms during the 2002/2003 influenza season in Japan. The specimens consisted of 239 nasal swabs and 268 nasal aspirates; 374 specimens were collected from pediatric patients (under 16 years of age) and 133 from adult patients. RapidTesta FLU AB was compared with cell culture and nested reverse transcription-polymerase chain reaction (RT-PCR). Cell culture detected influenza virus from 66.7% of the 507 specimens (influenza AH3: 44.0%, B: 22.7%). For nasal swabs, it had a sensitivity of 81.9% (77/94), a specificity of 97.9% (142/145) and an efficiency of 91.6% (219/239) for influenza A virus as well as a sensitivity of 80.0% (52/65), a specificity of 98.3% (171/174) and an efficiency of 93.3% (223/239) for influenza B. For nasal aspirates, RapidTesta FLU AB had a sensitivity of 83.2% (109/131), a specificity of 98.5% (135/137) and an efficiency of 91.0% (244/268) for influenza A as well as a sensitivity of 82.7% (43/52), a specificity of 97.7% (211/216) and an efficiency of 94.8% (254/268) for influenza B. RapidTesta FLU AB is characterized by high specificity, low false positive rate, and 10-minute detection of influenza virus. These advantages suggest that RapidTesta FLU AB is a useful kit to assist physicians in making a diagnosis of influenza on candidates for antiviral therapy.

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