We examined the susceptibilities of 100 Neisseria meningitidis strains isolated between 1990 and 2004 to 12 antimicrobial agents, finding the MIC₅₀ to be 0.031μg/mL and that of MIC₉₀ of benzylpenicillin (PCG), a type of penicillin, to be 0.063μg/mL. Two strains showed intermediate resistance (MIC of 0.125-0.25μg/mL). Two strains of the same origin also showed intermediate resistance (0.25-1μg/mL) to ampicillin (ABPC). For cephems, MIC₅₀ and MIC₉₀ of cefotaxime (CTX) were both 0.004μg/mL, while the MICs of ceftriaxone (CTRX) were all 0.004μg/mL, showing the strongest antibacterial spectrum. The three carbapenems surveyed meropenem (MEPM), panipenem (PAPM), and imipenem (IPM) also had a strong antibacterial spectrum in ascending order, with the MIC₅₀ and MIC₉₀ of MEPM, which was lowest, being 0.008μg/mL and 0.016μg/mL. Some 97%of MICs for ciprofloxacin (CPFX) were 0.004μg/mL but 3 strains showed resistance (0.125μg/mL).
No difference was seen between MICs of N. meningitidis strains originated from meningitis patients, patients other than meningitis, and healthy carriers. No difference was seen in MICs by serogroup (A, B, C, Y, W135 and NG).

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When measles antibody levels among pregnant women were measured with measles hemagglutinin inhibition (HI), 31% of subjects had negative HI antibody titers. When the same blood samples were tested with measles gelatin particle agglutination (PA) and neutralizing (NT), the percentages of those with negative antibody levels were 1% and 3%. We conducted the correlation between antibody titers measured by the three types of titration.
Correlation between NT and HI antibody titers higher than 1: 8 and that between NT and PA antibody titers were good, but 81 % of subjects whose HI antibody titer was below 1: 8 and all women with HI antibody of 1: 8 were found to have NT antibody titer higher than 1: 4. NT antibody titer higher than 1: 4 was found in 95% of women having PA antibody titer of 1: 256 and in 99% of those with PA antibody titer of 1: 512. Based on the relationships to measles NT antibody level, the majority of subjects with HI antibody titer higher than 1: 8 or PA antibody level higher than 1: 512 was reasonably assumed to be protected against clinical measles. PA seemed superior to HI in finding subjects with insufficient immunity against measles, because the former detects weak immunity more efficiently than the latter.

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Iwate Medical University Hospital (IMUH) is a general regional hospital with approximately 1, 000 beds and emergency facilities. Due to the increased prevalence of cases of hospital-acquired influenza during the 2004/5 epidemic season, measures to systematically and comprehensively prevent the spread of seasonal influenza such as reinforcement of the active surveillance of influenza and adequacy of patient placement and the introduction of a new zoning system based on transmission-based precautions, were implemented. This report compares pre-and post intervention, and analyzes the impact on the prevalence of hospital-acquired influenza patients.
Comparison of the prevalence of the 2005/6 season and 2004/5 season, irrespective of the fact that patients with influenza upon admission to the hospital doubled from 9 patients to 18, the number of influenza patients assumed to have secondary infections within the hospital markedly decreased from 48 to 20. In the 2004/5 season, a significant correlation was seen between the increase in the number of communityacquired influenza infections and the number of hospital-acquired ones. In contrast, no significant relationship was seen in the 2005/6 season. To exclude any influence due to seasonal differences in influenza epidemics, the secondary infection rate index one showed a decrease from of 36.8% to 23.7%. Based on the above results, influenza measures at IMUH in the 2005/6 season are considered to have suppresses the number of secondary infections occurring within the hospital.

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In January 2004, 20 patients and 19 staff in one ward became ill in an outbreak of norovirus-related gastroenteritis over a 12-day period. The epidemic curve indicated person-to-person transmission. Infection control measures were instituted in consultation with the government health authorities. A prompt rigorous response may have prevented spread to other wards. In March 2004, 54 staff and 1 member of a patient's family became ill in an outbreak of gastroenteritis. The source of norovirus contamination was associated with food served at the hospital restaurant. Secondary infection was prevented because the outbreak was recognized early and staff members with gastroenteritis symptoms were asked to stay home. Immediate control measures, such as identification and announcement of the outbreak, isolation of symptomatic individuals from others, personal protection, helped control the infection.

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Our recent studies have shown that type IV cytosolic phospholipase A₂ (cPLA₂) plays an important role in the expression of macrophage (MΦ) antimicrobial activity against the Mycobacterium avium complex (MAC). To clarify the modes of c PLA₂ participation in MΦ anti-MAC antimicrobial function in detail, we studied intracellular profiles of phospholilase A₂, focusing on c PLA₂, in MAC-infected MΦs, with the following findings: In murine peritoneal MΦs, cPLA₂ was constitutively expressed even in uninfected MΦs, and MAC infection did not increase intramacrophage c PLA₂ expression. In an RAW264.7 mouse MΦ cell line (RAW264.7 MΦs) infected with MAC, a portion of intracellular c PLA₂ was concentrated in MAC organisms residing within MΦ phagosomes. MAC infection upregulated intramacrophage c PLA₂ expression and induced its phosphorylation. These findings suggest that MAC infection of RAW264.7 MΦs may induce the activation of intracellular c PLA₂, translocating it to phagosomes engulfing infected MAC organisms.

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A spiral Gram-negative bacterium, Helicobacter cinaedi, has been isolated from clinical specimens of immunodeficient patients in Japan. We determined the isolation procedure and features using practical phenotypic tests for H. cinaedi isolated from blood culture. We applied 28 clinically isolated strains from 5 different metropolitan institutions, whose species was reconfirmed in technical support at another expert veterinary medicine institute in identifying H. cinaedi. We also used 6 strains of type and reference.
Positive signals from aerobic bottles in automated blood culture systems, BACTEC, were observed 4-9 days after culture was started. A thin spread colony was found 3-4 days after the start of subcultures consisting of growth on 5% sheep blood agar plates with immediate incubation under wet and microaerophilic conditions at 35°C.
In phenotypic tests, all specimens of H. cinaedi were shown to be positive in nitrate reduction and to be negative in both indoxyl acetate hydrolysis and urease activity, underlining the usefulness of these 3 phenotypes. Tests of alkaline phosphatase hydrolysis, growth at different temperatures, and growth with 1% glycin provided additional information when referencing standard results of identification. We took speculative profiling data of H. cinaedi identification with a simple phenotypic kit, Api campy, indicating its usefulness in testing.
These observations suggest combined methods of previously available tests (nitrate reduction, indoxyl acetate hydrolysis, and urease activity) with Api campy may be useful in differentiating H. cinaedi from H. cinaedi-like microorganisms when observing the characteristic thin spread colony within subcultures under microaerophilic conditions.

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The status of infectious mononucleosis in Japanese youth has been little studied. To gain more information, we analyzed data from tests for Epstein-Barr virus-specific IgM in about 180, 000 serum specimens sent to a commercial diagnostic laboratory from clinics nationwide between 1999 and 2006. The IgM antibody to the viral capsid antigen (VCA) was assayed by indirect immunofluorescence with P3HR-1 cells. In an agedistribution graph of IgM positive specimens, two peaks were found both in young children and youth. Boys outnumbered girls in the group of children aged 0 to 3, and vice versa in the group of youth aged 15 to 25. IgM-positive specimens increased from spring to autumn only in the youth group, suggesting that infectious mononucleosis in this group occurs more during this time. Infectious mononucleosis symptoms are more severe in youth, and further epidemiological studies are needed to clarify the disease status in young Japanese adults.

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The Ariake Sea area of Japan is endemic for Vibrio vulnificus infection. V vulnificus was isolated from slime from tidal flats, seawater, and fish Sea year-round as we reported previously. To identify new routes and factors of V. vulnificus infection, we studied V. vulnificus pollution of imported frozen Black Tiger shrimps purchased from a fish market in Kurume, Fukuoka, Japan. V vulnificus was isolated from 9 of 100 tails (9%) of Philippines products, 3 of 100 tails (3%) of Indonesia products, and 0 out of 100 tails (0%) of Madagascar products. Cytotoxin-hemolysin genes were identified in 7 V vulnificus strains isolated from patients with V. vulnificus septicemia, 9 strains from Philippine products, and 3 strains from Indonesian products. These results suggest that imported frozen Black Tiger shrimps are a new sources of V vulnificus infection.

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The frequency of diabetes mellitus has risen in Japan as the traditional diet has become increasing Americanized and society has aged. With this has come a rise in infectious diseases and complications elderly diabetic patients and a growing need for appropriate management to maintain their quality of life (QOL) and minimize medical measures.
Subjects were 98 diabetic patients-60 men and 38 women hospitalized for intravenous antibiotic treatment of infectious disease from 2002 to 2005. We studied plasma glucose control, plasma and urinary protein levels related to nephropathy, and inflammatory responses to treatment.
Subjects were divided into good (under 6.5%), fair (from 6.5% to 8.0%), poor (over 8.0%) and severe (over 10%) groups by HbAlc level on admission. We then compared white blood cell counts, CRP levels and the antibacterial medication periods.
Those with poorly controlled plasma glucose control, hypoalbuminuria and interrupted or untreated diabetes required significantly longer antibacterial administration.
Insulin was increased by the complications of infection, and decreased as infection ameliorated.
Appropriate antibiotic administration is essential for diabetic patients with infectious disease, in addition to early intervention, strict plasma glucose control, continuous treatment, and maintenance of good nutrition. Such treatment improves QOL, shortens antibiotic administration, staves off antibiotic-resistant bacteria, and cuts medical costs.

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We report the case of a patient with pneumonia caused by Pasteurella multocida (P. multocida)
An 83-year-old woman admitted for bronchiectasis, productive cough, and a high fever was found in chest radiography on admission to have a new infiltrative shadow in the left lower lung field. Chest computed tomography indicated bilateral bronchiectasis and an infiltrative lingular shadow. P. multocida was isolated from sputum samples. Biapenem and minocycline therapy ameliorated symptoms. Pulsed-field gel electrophoresis (PFGE) showed that the clinical isolate recovered was identical to the P. multocida isolate recovered from the pharyngeal swab specimen culture obtained from the patient's dog. Several years later, P. multocida subsp. gallicida isolates were recovered from human sputum and a canine pharyngeal swab specimen. PFGE confirmed these isolates to be identical and PFGE band patterns were identical to those of previous P. multocida isolates. These findings suggest that P. multocida was transmitted from the patient's dog to the patient and underscore the need to inform susceptible hosts at risk of contracting zoonotic agents about basic hygiene rules for keeping pets. PFGE data strengthened the evidence of zoonotic transmission of P. multocida through casual contact in a patient with a respiratory infection caused by this organism. PFGE should prove useful in both epidemiological tracing and preventing pasteurellosis and clarifying its pathology. Case reports of respiratory infections including pneumonia caused by P. multocida are increasing in humans, and P. multocida respiratory infections appear to occur mostly in patients with chronic respiratory disease. A history of pet exposure, even without bites or scratches, should alert the physician to P. multocida as a potential respiratory pathogen.

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We report the case of a patient with acute bronchitis caused by Neisseria meningitidis associated with HIV infection. A 36-year-old homosexual Japanese man being treated for HIV infection and reporting fever and a productive cough was found in laboratory findings to have elevated C-reactive protein but no leukocytosis. Chest radiography showed no infiltrates in either lung, but a sputum smear yielded large numbers of Gram-negative cocci, including some phagocytized by white blood cells. One day later N. meningitidis was reported to be the predominant isolate from sputum culture. The patient was diagnosed with acute bronchitis caused by N. meningitidis. The strain isolated from this patient was in serogroup B. The sequence type based on multilocus sequence typing was ST-5583, a subtype of ST-32. This strain is resistant to penicillin G in vitro, so we administered tosufloxacin at 600mg b.i.d., which showed excellent efficacy. Because of frequent sex with many men, homosexual contact was suspected as a possible route of infection. Meningococcal infections apart from meningitis rarely are surveyed epidemiologically in Japan, and the frequency of meningococcal infections in general is not clear. Vigilance is needed to identify trends in meningococcal infection, because N. meningitidis can cause acute bronchitis.

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The frequency of pulmonary involvement in leptospirosis is not well known in Japan. A 51-year-old man admitted with fever, bloody sputum, and general severe myalgia was found in laboratory studies to have thrombocytopenia, proteinuria, renal and liver dysfunction, and positive C-reactive protein. Chest computed tomography showed multiple tiny ill-defined nodules in both lungs. Intravenous ciprofloxacin treatment (600 mg/day) ameliorated symptoms and abnormal data. After starting therapy, we learned that he had been in contacted with rodents, and he was diagnosed with leptospirosis in a microscopic agglutination test.

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We report a case of 4 patients with pulmonary tuberculosis in a mental hospital located in Yamanashi, Japan, between 2000 and 2004 in which 3 isolates of Mycobacterium tuberculosis were analyzed using IS6110restriction fragment length polymorphism (RFLP). DNA fingerprinting showed them to be identical and the copy number to be two. Additional RFLP using (CGG)₅ fingerprinting yielded the same result and a copy number of 15, suggesting a M. tuberculosis outbreak.(CGG)₅ analysis thus proved useful in supplementary typing method like polymorphic G-C rich repetitive sequence (PGRS) or spoligotyping.

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Third-generation cephalosporin-resistant Enterobacter cloacae was isolated from the blood culture of a 31-year-old woman after bone-marrow transplantation. Since this strain was resistant to third-generation cephalosporins, the production of extended-spectrum β-lactamases (ESBLs) was suspected. PCR and a sequence analysis confirmed two ESBL genes, bla_SHV-12 and bla_CTX-M-14. No bacteria were detected after meropenem was administered, and symptoms abated. This is, to our knowledge, the first report in Japan of E. cloacae clinical isolates simultaneously producing both SHV-12 and CTX-M-14 ESBL. In cases where chromosomal AmpC over-production of E. cloacae concomitantly produces ESBL, caution should be exercised due to the potential development of resistance against extended-spectrum β-lactam agents.

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