We retrospectively analyzed 33 cases of children with systemic pneumococcal infections, 22 bacteremia and 11 meningitis, diagnosed and treated in Asahi General Hospital between 1985 and 1999. The median age at diagnosis was 15 months old and the incidence peaked in infants between 7 and 24 months of age (57.6%). Two cases showed low serum IgG2 levels. Fever was a common symptom in all cases and 13 (39.4%) presented convulsions. Meningitis [median age: 10 months] tended to occur, if not significant, in younger children than bacteremia [16 months]. All cases of meningitis were diagnosed 12 hours or later after the onset of fever, though 54.5% of the cases of bacteremia were diagnosed within 12 hours. The cases of meningitis showed statistically lower white blood cell counts [median: 9, 700/mm³] and higher CRP levels [median: 25.6 mg/dl] than those of bacteremia [23, 900/mm³ and 4.2mg/dl, respectively] at diagnosis. Although all cases of bacteremia were cured without any sequelae by antibiotic treatment, 3 cases (27.3%) of meningitis died and 4 (36.4%) developed severe neurological sequelae. Our findings suggest that the putative pathogenesis by which pneumococcal meningitis results from bacteremia and, taking in the account of the poor outcome of meningitis, may justify the early antibiotic intervention against pneumococcal bacteremia.

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We have evaluated a new HIV screening assay kit (Genscreen HIV Ag-Ab) for the HIVantigenantibody combined test by comparing with two HIV antigen-antibody combined assay kits (VIDAS HIV DUO, Enzygnost HIV integral). Genscreen HIV Ag-Ab is a microwell plate enzymeimmunoassay for the detection of HIV infection, based on the detection of anti-HIV-1/2 antibodies and HIV p24 antigen in human serum or plasma.
In this study, 90 samples of HIV-1 antibody positive sera and 670 samples of HIV negative sera were examined. The sensitivity was 100% and the specificity was 99.7%. All of HIV-1 group M sera (subtypes A to G and B/D), HIV-1 group 0 sera and HIV-2 sera in worldwide HIV performance panel-302 were positive with Genscreen HIV Ag-Ab. Ten commercially available HIV-1 seroconversion panels were tested to evaluate sensitivity of three HIV antigen-antibody combined assay kits. Genscreen HIV Ag-Ab detected infection at the same bleeds as VIDAS HIV DUO in 8 of 10 seroconversion panels and 1 to 2 bleeds earlier than Enzygnost HIV integral in 5 of 10 seroconversion panels. However, VIDAS HIV DUO indicated false negative on 5^th bleed in panel BB (PRA952). The result of the specimen was positive on 3^rd bleed, equivocal on 4^th bleed, negative on 5^th bleed and again positive on 6^th bleed. All of these specimens were positive by Genscreen HIV Ag-Ab.
Therefore, Genscreen HIV'Ag-Ab that shorten the window period is a useful and reliable for HIV screening test, especially in case of primary infection.

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Twenty-four Shigella strains of provisional serovars were isolated from travellers with diarrhea during 1993-2000 at Osaka Airport-and Kansai Airport-Quarantine Station. The outline of these cases were as follows.
1) The provisional serovars of these strains (number of cases) were S. dysenteriae 93-119 (2), S. dysenteriae 204/96 (4), S. dysenteriae 19809-73 (4), S. flexneri 88-893 (9), and S. boydii E16553 (5).
2) Symptoms of these cases were diarrhea, abdominal pain, fever, and vomiting. The ratios of each symptom were 100%, 50%, 50%, and 29.2%, respectively. Typical dysentery symptoms (mucous and bloody stool) were observed in three cases
3) In six cases (25.0%), plural kinds of entero-pathogenic bacteria were isolated, and in four cases, two kinds of Shigella serovar (known and unknown type) were isolated.
4) The major regions where these travellers were infected was South-west Asia (79.2%).
5) Twenty-three of the Shigella strains (95.8%) of the provisional serovars were resistant to two or more drugs tested (SM, CP, TC, KM, ABPC, NA, and OFLX). The most predominant drug resistance pattern was SM. CP. TC. ABPC.

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The time kinetics of poliovirus and secretory IgA (sIgA) antibody titers were examined in fecal samples from four vaccinees immunized with two doses of trivalent oral polio vaccine (TOPV) from 1996 to 2000. Poliovirus types 1 and 2 multiplied in the human intestine after the first vaccination, and poliovirus type 3 multiplied after the second vaccination. Additionally, poliovirus type 3 multiplied for several days in two cases after the first vaccination, and poliovirus types 1 and 2 multipliedfor before and after a week in one case after the second vaccination. Poliovirus type 2 multiplied most efficiently in the human intestine and stimulated the sIgA antibody response. The sIgA antibody titers are required to be≥1: 4 for poliovirus types 1 and 3, and≥1: 8 for poliovirus type 2 in 10% fecal suspension for adequate TOPV protection against reinfection. Serum neutralizing antibody titers against poliovirus type 3 were 1: 6 and 1: 8 for the shorter periods of 16 and 13 days, respectively, and 1: 60 and 1: 45 for 36 days in multiplication of poliovirus type 3 after the second vaccination. For double infection of poliovirus types 1 and 2, only the higher titers were obtained.
These results suggest that poliovirus multiplication induces the sIgA antibody inthe human intestine and the induced sIgA antibody defends the subject from poliovirus infection, and that the duration and the amount of virus multiplication tend to correlate with the levels of the serum neutralizing antibody titers.

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We investigated the usefulness of Rapidtesta Rota-Adeno (Daiichi Pure Chemicals Co., Ltd., Japan) for rapid detection of group A rotavirus and adenovirus simultaneously using immunochromatography with clinical samples. In investigation of the reaction of the kit to 5 strains of group A rotavirus, 13 strains of adenovirus and other intestinal viruses, specific lines were formed in red to group A rotavirus and blue to adenovirus. No cross reaction was observed with other intestinal virus. In measurement of detection limit, group A rotavirus (SA11) was detected at 10^4.4TCID₅₀/ml, serotype 3 adenovirus at 10^4.45TCID₅₀/ml. The detection limit of the kit was similar to other immunochromatographic assay or enzyme immnoassay kits and approximately 10 times higher than that of kits usinglatex gglutination test. In comparison with other testing kits in clinical samples, the concordance with other immunochromatographic assay was 99.2% (121/122) in group A rotavirus and 98.6% (138/140) in adenovirus. The rate of oncordance with latex agglutination test kit was 94.5% (69/73) in group A rotavirus and 92.3% (84/91) in adenovirus. The kit had high rates of concordance with other immunochromatographic assay kits and higher virus detection rates than those of latex agglutination test kits. Rapidtesta Rota-Adeno is able to detect group A rotavirus and adenovirus simply and rapidly. In addition, the two kinds of virus can be easily differentiated by color difference in reaction lines, suggesting that the kit is useful in clinical diagnosis.

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We evaluated a rapid diagnostic kit that detects influenza type A and B viral antigens by immunochromatography, Quick Vue^®Influenza Test (Quidel Corp., San Diego, CA, USA), with 425 specimens collected from patients with influenza-like symptoms at three hospitals between January and March 2001. The specimens included 184 nasal aspirates, 140 nasal swabs, and 101 throat swabs. The test correctly identified 179 of the 204 culture positive specimens and 203 of the 221 culture negative specimens; the sensitivity and specificity compared with the culture were 87.7% and 91.9%, respectively. The sensitivity of the test was 92.6% (112/121) for nasal aspirates, 83.7% (41/49) for nasal swabs, and 76.5% (26/34) for throat swabs, which is similar to the results for conventional rapid enzyme immunoassay kits for influenza virus infection . The sensitivity and specificity of the Quick Vue^®Influenza Test were equivalent to those of Flu OIA^® (BioStar, Inc., Boulder, CO, USA), with the agreement of 84.2%. Although the Quick Vue^® Influenza Test does not differentiate betweeninfluenza A and B viruses, the easy-to-use kit detects both types in the physician's office, allowing physicians to make a decision on prescription of neuraminidase inhibitor therapy during the initial visit.

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[in Japanese]

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We report a case of leptospirosis infected in Sabah, Borneo island, Malaysia. The case is 25-year old male who had participated in the EcoChallenge Sabah 2000 Expedition Race, a multisport event held during August 20 to September 3, 2000 at various sites in Sabah in Malaysian Borneo. He developed a high fever and headache on September 7, and he was admitted to our hospital on September 9. On admission he also had conjunctivitis and myalgias. Laboratory findings on admission revealed leukocytosis with left shift, slightly elevated transaminase levels, high CRP levels and proteinuria. Plasmodium spp. were negative on blood smears, and no bacteria were isolated from blood and feces cultures. We performed the laboratory tests for leptospirosis, based on the information about the probable leptospirosis outbreak among athletes who participated in the EcoChallenge Race, however both Leptospira antigens and antibodies were negative at that time. We diagnosed leptospirosis clinically because he manifested persistent symptoms, and minocycline 100mg b.i.d. was administered intravenously resulting in excellent efficacy. Serum antibody tests by microscopic agglutination test (MAT) at convalescent stage revealed significant increased antibodies against Leptospira interrogans serovar hebdomadis, and the diagnosis of leptospirosis was confirmed . Infectious diseases have been global and it is important to have information concerning worldwide infectious disease situations as much as possible for accurate diagnosis.

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