Vibrio vulnificus is found in marine waters near the coast around the world. Infection with this gram-negative rod, via ingestion of raw seafood or via a skin wound following contact with contaminated estu-arine or marine water, can cause necrotizing fasciitis and sepsis. Most of patients with Vibrio vulnificus infection have underlying liver dysfunction or diabetes mellitus. Due to the high mortality and short latent peri-ods, control of this infection depends on early identification of the bacterial species and prompt initiation of intensive care. Accordingly, the development of a technique that can identify this microbe quickly and accu-rately is of great importance. Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplifi-cation method to detect specific genes with rapidity and high sensitivity. In this study, we developed LAMP for the detection of Vibrio vulnificus. Using 28 Vibrio vulnificus strains and 53 other bacterial strains, we con-firmed the high specificity of this method. Moreover, our LAMP method also showed high sensitivity, with aminimum detection level of one colony-forming unit per test. Furthermore, we developed simplified and con-ventional pretreatments for the method using experimental animal models. All of these attempts have lod to our non being able to detect Vibrio vulnificus within 1 hour.

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Measles and rubella combined (MR) vaccine and two-dose-vaccination have been used in Japan since 2006. only children undergoing monovalent measles and rubella vaccination undergo a second vaccination. We intend to administer MR vaccine twice to Japanese children from 2011, so studied the safety and effi-cacy of two-dose MR vaccination. Subjects were 75 pre school children undergoing MR vaccine manufac-tured by Biken at one year old in a clinical trial. Children were observed for adverse events for 28 days af-ter the second MR vaccination. Efficacy was determined by measuring antibodies for measles and rubella before and after (six to eight weeks later) the second vaccination. Results showed that fever frequency de-creased significantly from 27.3% to 14.9% (p<0.05), and eruption decreased from 12.2% to 6.8% from the first to the second vaccination, whereas, the frequency of redness and swelling at the inoculation site in-creased from 7.3% to 10.8% and 2.9% to 8.1%. Differences are not statistically significant. Measles antibodytiter determined by NT assay and rubella antibody titer measured by HI assay increased significantly from prevaccination to postvaccination (p<0.0001). Measles antibodies measured by NT and EIA assays and ru-bella antibody measured by HI assay turned positive in all subjects after the second MR vaccination. In con-clusion, two-dose MR vaccination should be safe and effective in eliminating measles and rubella in Japan.

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Clostridium difficile is a major causative agent of antimicrobial-associated diarrhea, and the leading cause of nosocomial diarrhea. We clarified intestinal colonization and nosocomial spread of C. difficile in pediatric cancer patients undergoing antineoplastic therapy during long-term hospitalization. Subjects were 10 chil-dren with pediatric malignant diseases admitted from November 2005 to December 2006, aged 5 to 15 years, who received antineoplastic agents. Stool specimens were examined at hospitalization, after each course of treatment with antineoplastic chemotherapy, and when symptoms such as diarrhea or fever occurred.
While C. difficile was detected from stool specimens of 8 of 10 children during their hospital stay, 6 of these 8 children were negative for C. difficile on the day of their admission. These results demonstrate that the use of antimicrobial agents and antineoplastic agents lead to overgrowth of C. difficile in intestinal tract of pediatric cancer patients.
Five of the 8 children carried toxin A-positive, toxin B-positive C. difficle and 2 were diagnosed with C.difficile-associated diarrhea (CDAD). This demonstrates that CDAD is not a rare infection in pediatric cancer-patients. Nine C. difficile isolates from 8 children were analyzed by PCR ribotyping. Two isolates from 2 chil-dren were typed into the same type banding patterns of the remaining 7 isolates from 6 children were unique.

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[Objectives] Preparedness plans for pandemic flu are published in many countries. Since the details of pandemic flu are still not clear, mathematical models are widely used for the development of pandemic flu preparedness plans. Obtaining actual numbers for parameters in a mathematic model is very difficult. Our objectives were (1) to obtain realistic estimations of what proportion of people will decide to stay at home during pandemic flu and (2) to investigate reasons for their decisions. If the number of parameters is obtained, we can apply these parameters to the mathematical pandemic model.
[Methods] In April 2007, we a surveyed 2, 614 households, selected randomly from 250, 000 in Japan. “Reason to stay at home during a pandemic flu, ” “Working at Home”, and “food inventory” were asked. We analyzed the “decision of whether to stay home” by multivariate analysis.
[Results] We collected responses from 1, 727 households (5, 381 individuals). Of these, 46.1% would definitely stay at home, 47.1 % would leave if necessary, and 6.7% would leave anyway. We found that “30-40 years old, ” “vaccination of influenza, ” and “cars and motorbikes as normal transportation” significantly affect the decision to “stay at home.”
[Conclusions] We identified major factors for the decision of general Japanese people to stay home during pandemic flu. The fact that people most likely to go out were 30-40 years old suggests a close relationship to workplaces policy. To encourage people to stay at home during pandemic flu, management and human resource management policies in the workplace are thus important.

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We studied 96 mass outbreaks of infectious gastroenteritis due to Norovirus in winter 2006-2007. Of these, 56 occurred in welfare institutions for aging adults 31 in hospitals, and 9 in other facilities suchas kinder gardens. Affected staff accounted for 25.9% and users (inpatients, etc.) for 74.1 %. The shortest outbreak lasted 10 days and the longest 67 days. We found a positive corelation between periods from the beginning of an outbreak to warnings by public health centers and periods from the beginning to the end of outbreaks. The sooner advice was aired by public health centers, the sooner outbreaks ended. Dementia among users and insufficient knowledge and skills of staff were high risk factors in outbreaks. All 74 of specimens which we examined showed the GII4 genotype. We observed reoutbreaks at three institutions. We compared first and second specimens from the same instition. Two specimens from the second outbreak belonged to the same cluster as the first outbreak. We analyzed 310 bases of RT-PCR products in Capsid regions in both specimens, finding three point mutations accompanied by amino acids changes. This may change the antigenicity of Capsid protein, and may be why reoutbreaks occurred so quickly.

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After severe exposure to suspected rabid animal, WHO recommends a complete vaccine series using a potent effective vaccine that meets WHO criteria, and administration of rabies immunoglobulin (RIG). RIG is not available globally, and is not marketed in Japan. If pre-exposure prophylaxis for rabies is given, RIG is unnecessary even after severe exposure. It is thus important to give pre-exposure prophylaxis for rabies to people who plan to go to rabies-endemic areas.
In Japan, pre-exposure prophylaxis for rabies consists of 3 doses of cell-culture rabies vaccine. The first two doses are given 4 weeks apart, and the third dose is given 6-12 months after the first dose, all of which are injected subcutaneously (standard regimen). People who plan to travel abroad to rabies-endemic areas may know of their destinations only 1 or 2 months in advance at best. Therefore, it is virtually impossible to complete the 3 dose regimen for rabies in Japan.
Pre-exposure prophylaxis recommended by WHO consists of 3 doses given intramuscularly on days 0, 7, and 28, making it possible to complete pre-exposure prophylaxis in one month. This WHO recommended pre-exposure prophylaxis using Japanese cell-cultured rabies vaccine (PCEC-K) has not been studied, so we elected to fill the gap using PCEC-K, administered based on the WHO recommendation and examined its efficacy and safety.
Subjects were 26 healthy volunteers with no previous rabies vaccination giving oral and written consent. Vaccine was administered on days 0, 7, and 28, and rabies antibody levels were tested on days 7, 28, and 42. On day 7, every antibody level was negative. On day 28, antibody levels were between 0.7-3.5EU/ mL, with the exception of 3 cases still negative. On day 42, all cases, including the 3 negative cases, exceeded 1.6EU/mL, providing sufficient protection against rabies. This result was not inferior compared to the standard regimen. Local adverse effects such as erythema and pain were noted, but none were serious.
In conclusion, WHO recommended pre-exposure prophylaxis for rabies using PCEC-K is considered effective and safe.

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We evaluated a novel anti-human immunodeficiency virus type-1/2 (HIV-1/2) antibody detection kit for detecting anti-HIV-1/2 antibodies in whole blood based on the counting immunoassay (CIA) using an automated immunochemical analyzer (PAMIA-40i). This kit to detected all antibodies tested including those against HIV-1 subtype A to F, B/D in group M, HIV-1 group O, and HIV-2, and captured antibodies 4 to 7 days earlier than immunochoromatocraphic tests in the commercial seroconversion panel. In this study using 70 HIV-seropositive patients and 90 HIV-seronegative healthy individuals, both sensitivity and specificity were 100%. This automatic system using CIA for whole blood can be completed within 15min and examine many samples simultaneously. This system used latex-counting technology and reliably detects the low-titer antibodies in whole blood.

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A 26-year-old male was hospitalized with fever and pharyngeal pain. Liver dysfunction and an increase in the percentage of atypical lymphocytes in the peripheral blood were detected. Computed tomography showed pneumonia involving the right lung and synpneumonic pleural effusion. Serum immunological tests showed positive results for Epstein-Barr virus (EBV) viral capsid antigen (VCA) IgM and IgG antibodies andChlamydophila (Chlamydia) pneumoniae (C. pneumoniae) IgM and IgA antibodies on admission. The pneumonia and pleural effusion were no longer detectable after a week of treatment with starting azithromycin. At 7 weeks after admission, the liver function test results returned to within normal limits, the serum became negative for EBV VCA IgM antibody, theC. pneumoniaeIgM antibody titer decreased, and theC. pneumoniaeIgA and IgG antibody titers increased. This case was suspected to have infectious mononucleosis caused by primary coinfection withC. pneumoniaeand EBV.

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We report a case of acute respiratory distress syndrome caused by uropathogenicEscherichia coliinduced sepsis and treated successfully.
A 56-year-old women admitted for high-fever, dyspnea, and disturbance of consciousness on September 11, 2006, was found in chest computed tomography (CT) on admission to have diffuse infiltration with bilateral pleural effusion. Abdominal CT on admission showed left hydronephrosis complicated with ureteral stones. Because of severe hypoxemia, mechanical ventilation was started from hospital day 1. She went into shock soon after admission. Under mechanical ventilation, she was administered several antibiotics and dopamine. Because sera endotoxins were elevated, she was treated by endotoxin adsorption therapy on hospital day 3. A urethral stent was indwelled in the ureter for drainage after endotoxin adsorption therapy. BecauseEscherichia coliwas isolated from urine and blood cultures, she was diagnosed with acute respiratory distress syndrome (ARDS) caused byE. coliinducing septic shock. After therapy, her condition improved, and she was extubated on hospital day 9. Extracorporeal shock wave lithotripsy was conducted on hospital day 19 and she was discharged.

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Cases of septic pulmonary embolism (SPE) diagnosed clinically by CT after dental extraction rarely include verification of bacteria from the local infection site. We report the case of a 70-year-old man without background disease suffering severe pyothrax after dental extraction. We detected two species of oral bacteria from his pleural effusion. Treatment was so difficult that it required surgical debridement by video assisted thoracoscopic surgery (VATS), even after the appropriate administration of antibiotics.
According to the American Heart Association (AHA) prophylaxis guidelines for preventing infective endocarditis indicate that it is uncommon to prescribe antibiotics to patients without background disease after dental extraction. No appropriate Japanese guidelines exist considering the prevention of SPE causing severe pyothorax as in our case.
The hematogenous spread of bacteria such as SPE caused by sepsis after tooth extraction thus requires more attended careful consideration in clinical practice if patients are to be properly protected against potentially serious complications.

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Multidrug-resistant Pseudomonas aeruginosa(MDRP), defined as Pseudomonas aeruginosa resistant to aminoglycosides, carbapenems, and fluoroquinolones, has emerged as an increasingly problematic cause of hospital-acquired infection. With parenteral colistin unavailable in Japan, effective antimicrobial options are severely limited. We report a case of MDRP bacteremia successfully treated with antibiotic combination therapy screened by a Break-point Checkerboard Plate.
A 54-year-old man with malignant lymphoma who became febrile 9 days after a recent course of chemotherapy had a neutrophil count of 176/μEL. Treatment with meropenem and vancomycin was ineffective and high fever persisted. Methicillin-resistant Staphylococcus aureus(MRSA) and MDRP were isolated from blood culture and combination therapy with aztreonam and amikacin was selected for MDRP based on Break-point Checkerboard Plate' results. Linezolid was used for MRSA. The patient recovered successfully from MDRP and MRSA sepsis.

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