Japanese encephalitis (JE) cases confirmed by serological and/or virological tests, and clinically typical fatal JE cases have been collected using individual report cards in Japan since 1965. A total of 324 confirmed cases (male: 167, female: 157) reported between 1982 and 1996 were analyzed . Annual incidence of JE cases was less than one hundred cases from 1982 to 1991, and less than 10 cases after 1992. Age distribution of the patients was: 0-9 years old, 43 cases (13%); 10-39 years old, 30 cases (9%); 40-69 years old, 161 cases (50%); over 70 year old, 90 cases (29%). The highest incidence in male cases was observed in the age group of 50-59 years, and that in female was in 60-69 years. Most of the patients (95%) were living in the western parts of Japan. No patient was reported from Okinawa, southernmost prefecture of Japan, and from Tohoku-Hokkaido area, northern parts of Japan. The date of onset were distributed from the end of July to the end of October, and the highest incidence was observed in the end of August . Prognosis of the patients were: complete recovery, 99 cases (31%); sequelae, 156 cases (48%); fatal, 56 cases (17%); unknown, 13 cases (4%). Vaccination histories of patients were reported as: vaccinee, 4 cases (1%); incomplete vaccinee, 14 cases (4%); non-vaccinee, 181 cases (56%); unknown, 125 cases (39%). Spread of JE virus in Japan has not been diminished as shown by the data of antibody acquisition of young swine in every summer in Japan. Based on these observations we conclude that JE vaccination has contributed to maintaining the low JE incidence among children in Japan.

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Recentry, the efficacy of oral vitamin A supplementation for measles and respiratory syncytial (RSV) infection has been evaluated in developing countries. However, in developed countries where vitamin A defiency is little worth consideration, few studies have been conducted on the effect of vitamin A supplementation.
The effect of oral vitamin A (100, 000 IU) supplementation was evaluated in 105 children with measles (age 5 months to 4 years) and in 96 children with RSV infection (ages a month to 2.5 years) in Fukushima, Japan. Comparisons were made of clinical signs, duration of hospitalization and complications between treated groups and non-treated groups. Treated group (measles n=47, RSV n=54) and non-treated groups (measles n=58, RSV n=42) had similar baseline characteristics. Patients with measles given a vitamin A supplementation had a shorter duration of cough (7.2±1.6 vs 9.2±1.8 days, p<0.05) and patients with severe RSV infection given a vitamin A supplementation had a shorter duration of retraction (3.6±1.4 vs 5.3±0.8 days, p<0.05) and wheezing (4.4±1.7 vs 6.3±1.5 days, p<0.05). Toxicities, including excess vomiting and bulging fontanel were not observed.
Our findings may suggest the efficacy of oral vitamin A supplementation for measles and severe RSV infection, in children who have no malnutrition.

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During the period of investigation from Sept. 4, 1994 to Dec, 1996, a total of 11, 446, 534 overseas travellers were quarantined at Kansai Airport Quarantine Station, and 22, 187 voluntarily reported of episodes suffering from diarrhoea. Bacteriological examination of the stools a total of 9, 299 individuals' was performed, and the following results were obtained.
1) Various enteropathogenic bacteria were isolated from 33.3% of the stools examined . Bacterial species isolated were as follows: Plesiomonas shigelloides, 2, 066 cases (66.7%); Vibrio parahaemolyticus, 358 cases (11.6%); Aeromonas sobria, 360 cases(11.6%); Shigella spp., 291 cases (9.4%); Salmonella spp., 183 cases (5.9%); A.hydrophila, 126 cases (4.1%); and V. cholerae non-01, 121 cases(3.9%). However, ETEC was not done with an object of test.
2) In 502 cases (16.2%), plural enteropathogenic bacteria were isolated from single patient, suggesting high frequency of a mixed infections.
3) From Feb. to Mar. 1995, thirteen cases cholera were found from patients who had travelled to Bali, Indonesia. Cases with enteropathogenic bacteria other than V. cholerae 01 were found without any seasonal variation.
4) The major regions where the travellers were infected with the pathogens are as follows: Vibrio spp., were from only Asia; Shigella, widely distributed but especially in India and Indonesia; P. shigelloides and Salmonella, widely distributed.
5) Among the Shigella strains, S. sonneiwere isolated the most, followed by S. flexneri, S. boydii and S. dysenteriae. A strain of S. boydii provisional serovar E 16553 was isolated from a patient infected in India.
6) Among the Salmonella serovars, Salmonella Enteritidis was isolated the most frequently(49 cases, 25.7%).
7) 265(89.2%) of 297 Shigella strains, 52(27.2%)of 191 Salmonella strains, and 19(95.0%)of 20 V. cholerae O1 were resistant to one or more drugs tested(SM. CP. TC. KM. ABPC. NA. OFLX).
8) All of the 20 V. cholerae O1 strains were Ogawa, El Tor. All of them were toxigenic strains.
9) The most frequently isolated serovar of V. parahaemolyticus was O3: K6. 89.8% of all V. parahaemolyticus strains were positive for thermostable direct hemolysin (TDH) gene, and 14.6% of them were positive for TDH-related hemolysin(TRH)gene by DNA-probe or PCR method.

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This paper investigated the efficacy of passive protection provided by milk (immunized milk) against enterovirus infection in mice experimentally infected with enterovirus.
Milk with a high antibody titer against six enterovirus serotypes was prepared from hyperimmunized goat.
In vivo and in vitro experiments were performed and the results showed that immunized milk has an antiviral activity against enterovirus infection.
Further observation was peformed using Coxsackie B 3 virus (CVB 3). When immunized milk was orally applied to mice prior to oral inoculation with CVB 3, preventive effects against viral infection such as reduction of histopathological changes in the heart and reduced detection of the virus genome in the organs were seen.
The antiviral effect was also indicated by the increase of CD4⁺T cells proportion in the i-IEL. The proportion of virus specific CD4+T cells was increased in mice treated with immunized milk, whereas no such increase was detected in control mice.
These results suggest that oral application of immunized milk is not only capable of preventing viral infection but also induces specific immunological responses. These phenomena may play an important role in host defense mechanisms.

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During the recent 2 years we experienced 5 children (2 months-5 years old) with lung tuberculosis, all of whom had positive tuberculin skin-tests, and were in close contact with their family members who had active tuberculosis. However, no abnormal findings on chest X-ray films were pointed out by 2 independent roentogenologists, and no increased levels of inflammatory markers including WBC numbers, CRP, and ESR were detected in all but one child. Moreover, mycobacterial examination of sputa and/or gastric aspirates by microscope, culture technique, and PCR amplification revealed no causative bacilli in 4 children. To clarify whether these children were affected by Mycobacterium tuberculosis, chest CT scan was applied. Surprisingly, all 5 children were revealed to have abnormal changes including primary complexes in the lung field. Taken together, it is important to pursuit the apparent lung tuberculosis in children with a positive family history and positive tuberculin skin-test.

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An epidemic of aseptic meningitis in Fukuoka Prefecture during April 1997 to August 1998 was studied to determine the serotype of viruses isolated in Fukuoka Prefecture. In Fukuoka Prefecture, bimodal peaks were seen in July and December 1997. Monthly changes of reported aseptic meningitis patients and period of virus isolation revealed that epidemics of the earlier part in 1997 was caused by echovirus 9 (E 9) and the latter part due to echovirus 30 (E 30). E 9 was isolated mainly in Chikugo Area from June to October 1997 but, E 30 was isolated all in areas of Fukuoka Prefecture . Isolation of E 30 continued after January 1998 in Fukuoka Prefecture.
Isolation of echovirus 18 started in June 1998. The main serotypes of isolates are changing.
The E 30 isolates are serotyped by neutralization with the aid of antiserum pools for enterovirus type differentiation, but serotyping was difficult with commercially available antiserum. The result of neutralization tests with standard serum and an immune albino rabbit serum prepared in our laboratory with the E 30 isolates indicated that the isolates in Fukuoka Prefecture was an antigenic varian

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All immunocompromised hosts, such as infants, the elderly, patients with advanced cancer, and patients being treated with immunosuppressants, etc., are said to be more susceptible to cytomegalovirus (CMV) infection or CMV disease. However, we quentioned the validity of this conclusion and attempted to detect CMV viremia in the plasma of subjects by using the AMPLICOR^TM CMV test (Roche Diagnostics Systems, Branchburg, NJ), the first standardized PCR kit for CMV infection. One hundred healthy volunteers whose CMV IgG titer was<4 and 100 healthy volunteers whose IgG titer for CMV was≥4 were studied. None of the subjects in either helthy group was positive for CMV viremia. Patients who were suspected of CMV infection were divided into four groups and tested: [1] 104 patients with benign disease, only one of whom was positive for CMV [2] 99 patients with hematopoietic malignancy who had not undergone bone marrow transplantation and all of whom were negative for CMV infection [3] 120 post-bone-marrow transplantation, 28 of whom were CMV positive, [4] 37 post-renal transplantation patients, 19 of whom were CMV positive. A statistically significant difference in CMV positivity was found by the non-parametric Kruskal-Wallis test (p<0.0001) among the four disease group. CMV infection has been said to occur in all types of immunocompromised patients, however, based on our findings, we conclude that CMV infection tends to occur in post-transplantation status and does not tend to occur in patients with hematopoietic malignancy if they have not undergone transplantation.

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Vibrio vulnificus (V. vulnificus) infection has recently been drawning attention as a high mortality disease especially in a patient with the preexisting chronic liver disease. The illness casued by V. vulnificus is divided into three groups such as primary septicemia, wound infection and gastrointestinal illness. Primary septicemia, which is the most common in Japan, is defined as a systemic illness presenting fever or hypotension with recovery of V. vulnificus from blood or tissue without the apparent primary focus of infection. We diagnosed four cases as infectious diseases of V. vulnificus by isolating it from each clinical material in Kurashiki Central Hospital from 1984 through 1997. We investigated clinical manifestations of the four cases including season of the onset, presence of drinking habit, underlying diseases, consumption of raw seafood, symptoms, presence of disseminated intravascular coagulation (DIC) or shock, laboratory data, administered antibiotics and the outcomes of the treatment. And for each strain, we also performed in vitro drug susceptibility tests. The age of the patients ranged from 49 to 61 years old (mean 56), and all of the patients were male. Each of them had a chronic liver disease as an underlying disease. Two of them had a history of raw seafood consumption prior to the onset of the illness. Skin manifestations appeared in two of the four patients. All the patients complicated septic shock and DIC. V. vulnificus was isolated from the venous blood cultures of them. Three of the four were given a diagnosis of primary septicemia and one was made a diagnosis of acute cholecystitis which has never been reported previously. Three of the four patients died and only the rest was alive as a result of antimicrobial therapy. In the sensitivity tests, the four strains were revealed to be very sensitive to the antimicrobials such as minocycline, cephalosporins of the third generation and carbapenems. Once patients with a chronic liver disease are infected with V. vulnificus, their prognosis is poor. Every effort should be made to advise not to have uncooked seafood. Physicians should be informed about the characteristics of the disease caused by this bacteria and treat any suspicious case promptly and appropriately.

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Human β-defensin-1 (hBD-1) and human β-defensin-2 (hBD-2) are new members of the defensin family. In this study, we investigated their gene expressions in the respiratory epithelial surface of the human lung and their bactericidal activities against Escherichia coli. Both hBD-1 and hBD-2 gene transcripts were detected in human lung tissue and cellular component of bronchoalveolar lavage fluid by reverse transcription-polymerase chain reaction. Synthetic hBD-1 and hBD-2 had dosedependent bactericidal activities against E. coli. The concentration for the 50% colony reduction of hBD-2 was 0.46 nmol/ml, that for HNP-1 2.15 nmol/ml, and hBD-1 99.3 nmol/ml under conditions nearly the same as in human bronchial airway surface liquid. We prepared an antiserum against hBD-2 and established a highly sensitive radioimmunoassay and quantified plasma hBD-2 concentrations in normal subjects and patients with pneumonia. The plasma concentration of hBD-2 in normal individuals was 8.3±0.9 fmol/ml (mean±SE). The mean hBD-2 plasma concentration for the 12 patients with bacterial pneumonia in the acute stage was 34.2±3.4 fmol/ml, significantly higher than normal individuals, and returned to the normal range after recovery. The presence of hBD-1 and hBD-2 in the airway tract and their bactericidal activity suggest that they function in innate airway mucosal defense.

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The susceptibility of Streptococcus agalactiae (S. agalactiae) clinical isolates of Juntendo University Urayasu Hospital, and type strain ATCC 13813 to beta-lactam antimicrobial agents was evaluated by means of macro-broth dilution MIC determination, killing kinetics and population analysis . When 10⁶ cells of S. agalactiae were inoculated and cultured in Todd-Hewitt broth containing two-fold serial dilutions of penicillin, the viable cell count showed that about 10² cells survived irrespective of the penicillin concentration which ranged from 0.063 to 128 μ/ml. The result indicated that S. agalactiae had tolerance to penicillin (MICs were around 0.063 μ/ml). Furthermore, the S. agalactiae strains were found to have a paradoxical response to penicillin in an acidic condition (pH 5.5). When the cell counts were performed at pH 5.5, about 10² cells survived at penicillin concentrations from 0.016 to 0.125 μ/ml, while about 10⁴ cells survived at the concentrations of 1 to 8 μg/ml . The antibiotic tolerance and paradoxical effects of S. agalactiae were also observed in killing kinetics. The ATCC 13813 and 10 out of 11 clinical strains showed slow response to penicillin-mediated killing at pH 7.8, and ATCC 13813 and one of the clinical strains showed a reduced response with increase in penicillin concentration at pH 5.5. These results suggested that the tolerance and paradoxical effect of S. agalactiae cells to betalactam antibiotics may be one of the reasons for frequent re-colonization of S. agalactiae at the time of delivery after the chemophylaxis in the 2nd trimester.

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We compared the Mycobacteria Growth Indicator Tube 960 (MGIT 960) and Ogawa medium (OM) for the detection of mycobacteria (acid-fast bacteria: AFB) using 882 sputum specimens. Overall, 120 strains of AFB were isolated by the MGIT 960 system and 99 strains of AFB were isolated by using OM. As far as Mycobacterium tuberculosis is concerned, 88 and 71 isolates were achieved by the MGIT 960 and OM respectively. A total of 28 isolates (18 isolates of M. tuberculosis and 10 isolates of nontuberculous mycobacteria: NTM) were detected by the MGIT 960 only whereas only 2 isolates (1 M. tuberculosis and 1 NTM) were detected by OM only. Of these sputum specimens, 72 were smear positive for AFB. The rates of smear negative but culture positive specimens were 8.0% (65 out of 809) for the MGIT 960 system and 6.2% (50 out of 809) for OM. The contamination rate for MGIT 960 was only 1.2%. The average time required for detection of M. tuberculosis was 14.1 days by the MGIT 960 system and 24.6 days by OM. For the NTM, the average detection time were 8.3 days for the MGIT 960 system and 22.8 days for OM. These results indicate that the MGIT 960 system allows detection of mycobacteria significantly faster than OM.

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Vibrio parahaemolyticus food poisoning, is the most prevalent among bacterial food poisoning inJapan. Study of epidemiologic markers is important in an attempt to trace the source of contamination.The purpose of this study was to compare seven different typing methods (serotyping, plasmidprofile, antibiogram, phage susceptibility.TDH production, tdh and trh gene and pulsed-field gel electrophoresis [PFGE]) for V. parahaemolyticus.
Outbreaks of V. parahaemolyticus food poisoning which occured during the 13 years from 1981 to1993 numbered 43 including 481 cases in Nagano Prefecture. Serovar O4: K8 was the most plevalentserovar isolated, serovar O2: K3, O4: K63 and O3: K5 followed. Forty one strains of V. parahaemolyticuswere used in this study. All of the strains were isolated from 12 food poisoning cases at NaganoPrefectual Research Institute for Health and Pollution.
Of the 41 strains, twenty two strains (O4: K8, O4: K63) were sensitive to both ∅ VP 253 and ∅ VP 143 phages. six strains (O3: K5) to phage ∅ VP 143. Thirteen strains (03: K29, O4: K11, O4: K12 and O5: KUT) were insensitive to both phages. CBPC, CBPC·ECEZ and CBPC·ECEZ·EKM·ESM resistant strains was determined in 22 strains out of 41 strains. Five strains of V. parahaemolyticuscarried plasmid. Of the 41 strains, thirty nine strains were possessive to tdh gene and productive toTDH. Chromosomal DNA of the isolates from 12 different outbreaks was analysed by PFGE after NotI digestion. PFGE analysis of the digested DNA yielded 11 to 21 DNA fragments. Twelve distinctivefragment patterns were identified in 41 V. parahaemolyticus isolates from 12 different food poisonings.
These results showed that the PFGE method is an useful tool to analyse an epidemiological surveyfor isolates of Vibrio parahaemolyticus food poisoning.

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A 63-year old female was admitted because of an abnormal shadow on chest X-ray film. Chest CT showed a nodular shadow in the right S⁶ and a patchy shadow in the right S¹⁰. Right lower lobectomywas performed under a diagnosis of lung cancer made by TBLB in the right S⁶. Pathological examinationof the resected lung revealed papillary adenocarcinoma in the right S⁶ and numerous cryptococciin the right S¹⁰. No cryptococcal infection was found in the resected lymph nodes.

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A 40-year-old female was admitted with right chest pain. SLE was abscent from her past history, although she complained of polyarthralgia in winter. Atypical pneumonia/pleuritis was suspected by chest X-ray film, showing a nodular shadow in the right lower field and moderate pleural effusion. Chlamydia pneumonia was diagnosed by elevated anti-C. psittsci antibody, while characteristics of pleural fluid revealed serositis accompained by SLE because of the high titered anti-DNA antibody and the low titered complement. She was cured by clarithromycin and subsequent administration of prednisolon and cyclophosphamide.

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