A total of 674 Salmonella serovar Typhimurium(S. Typhimurium)strains consisting of 522 domestic strains and 152 imported strains isolated in Tokyo, 1980-1998, were examined regarding their drug-resistance and phage-type.
Domestic strains accounted for 6.2% of all Salmonella(8, 359 strains)isolated from domestic cases, and imported strains accounted for 3.7% of all Salmonella(4, 083 strains)isolated from imported cases.
A drug-resistance test using 9 drugs(CP, TC, SM, KM, ABPC, ST, NA, FOM, and NFLX)showed that 245 strains(46.9%)of the domestic strains and 109 strains(71.7%)of the imported strains were resistant to some of the drugs, excluding FOM and NFLX. Drugs with a high resistance rate were TC, SM, ABPC, and CP for both groups. Drug-resistance patterns of the resistant strains varied among the 40 types. Among those, prevalent patterns recongnized were CP·ETC·ESM·EABPC, CP·ETC·SM·KM·ABPC, TC·SM, SM, and TC·KM in the domestic strains, and TC, CP·TC·SM·ABPC, CP·TC·ESM·EKM·EABPC, CP·ETC·ESM·EKM·EABPC·EST and TC·EKM in the imported strains. The results of the phage-typing test revealed that 31 strains of 52 domestic strains tested, and 13 strains of 46 imported strains tested were definitive type 104(DT104). Those resistance patterns were CP·ETC·ESM·EABPC·ESU(43 strains)and CP·ETC·ESM·EKM·EABPC·ESU(1 strain).

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AnaeroPack^® Malaria Culture System (SUGIYAMA-GEN Co., Ltd.) using AnaeroPack^®·plas (5%O₂, 5%CO₂) and AnaeroPack^®·CO₂ (15%O₂, 6%CO2) was evaluated by comparing with the standard laboratory in vitro continuous culture technique. Two culture-adapted strains of Plasmodium falciparum, SGE-1 (chloroquine sensitive strain) and K1 (chloroquine resistant strain), were continuously cultured for 26 days in vitro under the 3 systems. The parasite proliferation curves under the different set systems were paralleled in both strains, which demonstrate that this AnaeroPack^® Malaria Culture System is useful for the culture-adapted strains of P. falciparum. Although further test using isolates from falciparum malaria patients should be carried out, the AnaeroPack^® Malaria Culture System seems promising for the culture in the field studies.

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We have recently developed a method of in vitro cultivation of P. falciparum using a portable incubator and Anaero Pack®·CO₂ (Onda et al.), we applied semi-microtechnique drug susceptibility tests to the culture method to evaluate the system using several P. falciparum strains or isolates of different susceptibilities to chloroquine (SGE-1, FCR-3, K-1, Patient 1 and 2). The new method gave comparable results to those shown by the standard test employing a modular incubator chamber with standard gas composition of 5%O₂, 5%CO₂ and 90%N₂. Many useful data on the epidemiology of drug resistant malaria such as the emergence of multi-drug resistant isolates could be collected by applying this new method to the field survey.

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To investigate the incidence of diarrheagenic Escherichia coli among E. coli strains screened by commercially available O-antigen antisera, we used PCR to isolate 8 virulence genes (eae, bfp A, IpaH, LT, ST, VT1, VT2, and aggR) in 184 E. coli strains sampled from sporadic diarrheal children in our district. eae and bfpA are the localized adherence factor genes of enteropathogenic E. coli (EPEC). IpaH is the invasion antigen gene of enteroinvasive E. coli (EIEC), LT and ST are the toxin genes of enterotoxigenic E. coli (ETEC), VT1 and VT2 are the toxin genes of enterohemorrhagic E. coli (EHEC), and aggR is the adherence factor gene of enteroaggregative E. coli (EAggEC). The results were as follows: eae, 7 (3.8%); bfpA, 0 (0%); IpaH, 0 (0%); LT, 0 (0%); ST, 2 (1.1%); VT, 5 (2.7%); aggR, 8 (4.3%). Seven isolates with eae did not have bfpA, and did not show a localized adherence to HeLa cells. Seven of the 8 isolates with aggR showed aggregative adherence to HeLa cells, while their Oserotypes of them were O 111: H21 or O 111: HUT. Because of the low incidence of the virulence gene, the commercially available O-antigen antisera was not expected to be useful for the screening of diarrheagenic E. coli, except for EHEC and EAggEC. EAggEC may be important as a pathogen of sporadic diarrhea of children as well as EHEC.

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We studied the cefotaxime (CTX)-resistant (MIC≥32 μg/ml) clinical isolates of E. coli and K. pneumoniae in Teikyo University Hospital from 1990 to 1996. The incidence of CTX-resistant isolates was 0.4% (6/1, 282) in E. coli and 0.6% (7/1, 044) in K. pneumoniae, in 1990. In 1995, the incidence of CTX-resistance increased to 1.7% (50/2, 910) in E. coli (p=0.0013) and 7.2% (144/1, 996) in K. pneumoniae (p<0.0001).
These species have been detected in the stool (86 isolates), urine (59 isolates), sputum (15 isolates), pus (15 isolates), throat (10 isolates) and others (12 isolates) in 1995.
MIC₅₀ of ampicillin (ABPC), ABPC with clavlanic acid (CVA) 5μg/ml, piperacillin (PIPC), PIPC with CVA 5μg/ml, ceftazidime, CTX, ceftizoxime, cefpodoxime, cefepime, aztreonam, cefmetazole, latamoxef, and imipenem used against 33 isolates (11 isolates of E. coli, 22 isolates of K. pneumoniae), which were detected in 1996-1997, was >512μg/ml, 8μg/ml, >512μg/ml, 8μg/ml, 4μg/ml, >512μg/ml, 16μg/ml, >512μg/ml, 256μg/ml, 32μg/ml, 2μg/ml, 0.25μg/ml and 0.25μg/ml, respectively.
This susceptibility pattern were very similar to the Toho-1 type β-lactamases producing strains.

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Epidemiological and microbiological studies were carried out using 200 strains of pneumococci isolated from clinical specimens in 5 Kitakyushu municipal hospitals, between October 1994 and July 1995.
Eighty nine percent of pneumococci were detected in the specimens from the respiratory tract.
Pneumococci were isolated mainly from infants under 3-years of age and adults over 50-years of age, and the rates of isolation were 40.5% and 39.5%, respectively.
MICs of 8 antimicrobial agents, such as PCG, NFLX, CPFX, LFLX, FLRX, TFLX, SPFX, LVFX, were determined using broth microdilution methods.
According to NCCLS standard (1997), recovery rates of PSSP, PISP and PRSP were 48.0%, 39.5 % and 12.5%, respectively. Among 7 quinolones, TFLX, SPFX and LVFX were effective so far examined, except for a few resistant strains.
Four cases in which quinolones resistant pneumococci were isolated were reviewed retrospectively. Among them 3 cases had been given quinolones before the strains were detected.

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The efficacy and adverse effects of prophylactic administration of Sulfamethoxazole-Trimethoprim (ST) for Pneumocystis carinii Pneumonia (PCP) were assessed in patients with connective tissue diseases (CTD) Eightly four patients who were receiving more than 40mg/day of prednisolone were entried in the present study. Patients with at least one of the two PCP risk factors (interstitial pulmonary fibrosis and lymphopenia), were administred either one (11 patients) or two (26 patients) ST tablets/day. The remaining 47 patients who did not receive ST served as the controls. Although PCP was detected in 4.3% of the patients in the no-ST group, none of the patients who received ST developed PCP. Five of these 26 patients who received two tablets of ST/day, experienced adverse reactions. However, no adverse reactions were detected in the patients who received one tablet of ST/day (p<0.05). Abnormal laboratory data were obtained for 10 (38.5%) of the patients who received two tablets of ST/day and for 4 (36.4%) of the 11 patients who received one tablet of ST/day. The results of the present study suggest that the prophylactic administration of one tablets of ST in patients with CTD that have at least one of the two PCP risk factors is effective in preventing PCP.

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From October through December, 1998, person to person infection caused by Shigella sonnei had occured in the day nursery in Hachioji-city Tokyo, and a total of 41 patients including 3 suspected cases and 3 carriers had been confirmed. Although one case was imported case which is one-year-old kindergarten child, the remaining was domestic case. Of patients, 33 cases (80.5%) were a three-yearold kindergarten children and their families, accounting for 20 and 13 cases, respectively. From the data of symptom onset of patients, epidemic could distinguish to the former part and the later part. The recur or reinfection, and re-detection case was observed in the later part. Clinical symptom of the patients was diarrhea (100%), fever (80%) and abdominal cramps (70%), and LVFX for adult or FOM for child was used for the therapy.
In the colicin typing test and the antibiotic susceptibily test for 9 reagents, almost isolates in the former part were type 0 and susceptible, and MBC for FOM ranged from 6.25 to 100 μg/ml, whereas those in the later part was type 2 and resistant for the TC, and showed highly MBC for FOM with 50 or 100 μg/ml . However, both isolates showed same pattens in plasmid profiles and DNA fingerprints by RAPD analysis. On the other hand, the strain from imported case was also colicin 0, but it was diffrent as regards resistant for ABPC and ST and two genetic analysis.

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To identify the source and route of verotoxin-producing Escherichia coli (VTEC) infection in humans, we tried to isolate VTEC from fresh deer dung collected from free-range animals in two parks during the period from August 1997 to January 1998. The results are presented below.
1) VTEC were isolated from 21 of 200 deer dung samples (10.5%), consisting of 15 of 100 samples (15.0%) collected in park A and 6 of 100 samples (6.0%) collected in park B, suggesting that the incidence of VTEC isolation differs depending on location.
2) With respect to typing of verotoxin, the 21 isolated VTEC strains consisted of 10 strains (47.6 %) as VT1 producer, 5 strains (23.8%) as VT2 producer, and 6 strains (28.6%) as double producer of both types.
3) With respect to serogroup of the isolated VTEC strains, 2 strains belonged to O128: H2, 1 strain each belonged to the O8: H10, O128: H12, and O169: HUT groups. The remaining 16 strains failed to be identified as particular serotypes. Regarding local distribution of the serotype, in park A, 1 strain each belonged to the O128: H2, O8: H10, and O169: HUT groups. The remaining 12 strains did not clearly show particular serotypes. In park B, 2 strains belonged to O128: H2, and 4 strains failed to show particular serotypes. The remaining 1 strains showed autoagglutination.
In conclusion, we isolated VTEC strains from deer that showed types of toxin and serogroups identical to those of human VTEC. Therefore, VTEC found in deer dung could well be a source of VTEC-infectious diseases in humans.

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Although nasal vaccination has emerged as an interesting alternative to intramuscular or oral vaccination, knowledge is scarce about the immune responses after such immunization. In the present study, we inoculated purified Pertussis Toxin (PT) and Filamentous Haemagglutinin (FHA) with or without adjuvant (kayexalate). or Diphtheria acellular Pertussis Tetanus (DaPT) combined vaccine to mice intranasally three times every four weeks to investigate the references of the immunoresponses between nasal and intramuscular vaccination. The levels of pertussis specific serum IgG antibodies (Abs) and secretory IgA Abs in the nasal wash were measured by ELISA, and cytotoxic T cell activities were examined by proliferative response, and compared with the result from intramuscular inoculation. We also studied the efficacy of adjuvant in the nasal vaccination.
The intramuscular inoculation of pertussis vaccine induced serum IgG antibodies and cellular immunity against PT and FHA, but did not induce local IgA antibodies. On the other hand, the nasal inoculation induced both serum and local antibody resposes. Moreover, it also induced significant cellular immunity to pertussis antigen. In nasal vaccination, the inoculation with adjuvant was superior to inoculation without adjuvant for the induction of both humoral and cellular immunity.

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Directigen Flu A, an enzyme immunoassay membrane test for the detection of influenza A virus, was compared with serum hemagglutinine inhibition assay in adult and elderly patients.
Throat specimens were collected by vigorous swabbing from febrile patients who were suspect for influenza by clinical symptoms and tested with Directigen Flu A. Serum samples were collected from the patients at onset of illness and two to eleven weeks later and tested for antibody titer to influenza A/H1N1, A/H3N2, and B. A total of 57 patients were involved in this study; 32 under 59 years of age and 25 over 60 years of age.
Influenza was diagnosed in 42 patients by HI titer elevation (73.7%). Directigen Flu A was positive in 25 patients. Results of Directigen Flu A and HI test agreed in 40 patients. Sensitivity and specificity of Directigen Flu A were 59.5% (25/42) and 100% (15/15), respectively. There was no significant difference in sensitivity between the two age groups.
These results indicate the potential usefulness of Directigen Flu A in the surveillance of influenza A infection in the geriatric population. Directigen Flu A gives results within 15 minutes without expensive equipment. Use of Directigen Flu permits the timely administration of antiviral therapy and infection control among hospitalized and institutionalized geriatric patients.

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A 46-year-old male patient with alcoholic cirrhosis of the liver was carried to our out-patient clinic as he had developed shock while under routine follow-up, and died on the way to the hospital. He had been admitted several times since the diagnosis eight years ago, and was finally discharged from the hospital six weeks ago with improved physical condition and laboratory findings. A vesicle and bulla formation with phlegmon on the skin of right leg and sole of foot was noticed. Vibrio vulnificus was detected from the purulent discharge of the skin on culture. We conclude that the patient developed V. vulnificus-septicemia which resulted in sudden death. Since V. vulnificus infection may frequently take a fulminant course in patients with liver cirrhosis, adequate measures should be taken for early diagnosis and treatment to prevent the fatal outcome.

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