Human respiratory syncytial virus (RSV) is the most common worldwide cause of lower respiratory tract infections (LRI) in infants less than 12 months of age. RSV isolates can be divided intogroup A and B. In addition, there were many genotypes within each group, and these genotypeshave evolved global setting with temporal and geographic clustering. Many cellular genes encodingcytokines and chemokines which are activated by RSV infection has now been focused for the elucidation of pathophysiology of RSV LRI. The prophylaxis against RSV infection by vaccination hasbeen unsuccessful because of its adverse effects. No valuable anti-RSV drugs for clinical use havebeen yet developed. Therefore RSV LRI has been treated mainly symptomatically. Recently humanized anti-RSV F protein monoclonal antibody was developed and prescribed for prevention in high-risk infants such as premature ones and those with chronic lung and congenital heart diseases. It reduced the incidence of hospitalization significantly.

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In this study we analyzed the symptoms of gastroenteritis or food-borne disease caused by the10 most prevalent pathogens: Norovirus, Salmonella, Vibrio parahaemolyticus, Campylobacter jejuni, Clostridium perfringens, Shiga toxin-producing Escherichia coli(STEC), enterotoxigenic E. coli(ETEC), Shigella sonnei/flexneri (Shigella), Staphylococcus aureus, and emetic-type Bacillus cereus.The symptoms diarrhea, vomiting, fever, abdominal pain, and headache, and the incubation period in 646 casesin 10 districts of Kyushu between January 2000 and December 2004 were recorded. The pathogenwith the shortest mean incubation period wasB. cereus(0.8 h), and was followed byS. aureus(3.3 h)C. perfringens(10.7 h) and V. parahaemolyticus(16.4h). All the patients infected withB. cereusandS.aureusdeveloped symptoms within 6 hours, and those infected with V. parahaemolyticusandC. perfringensdeveloped symptoms within 24 hours. Bloody diarrhea was associated with STEC andShigella.but rare with other pathogens. Vomiting was associated with almost all cases ofS. aureusandB.cereusinfection, and occurred in 71.5% of the Norovirus cases and 56.1% of theV. parahaemolyticuscases. Vomiting was less common in the C. perfringens(22.0%) and the ETEC and STEC (both about5%). Bloody diarrhea, abdominal pain, and vomiting were statistically significantly more commonwith STEC 0157 infection than with STEC non-0157 infection. Since the cases analyzed in this studyincluded all degrees of illness, mild to severe, and a wide range of ages, the information obtained willserve as a good reference material for administrative and laboratory work when an outbreak takesplace.

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This aim of this study was to reveal an nual changes in antibiotic susceptibility, especially themacrolide susceptibility of streptococcus pyogenes. A total of 755 strains of s. pyogenes were clincalyisolated from throat swabs of children from 1995 through 2004 in Chiba Municipal Kaihin Hospital.All isoiates were fully suscepti ieto benzylpeniciilin, cefotaxim and cefaclor. The rate of resistance toerythromycin (EM) was over 10% every year after 2001 and 19% in 2004, and the rate of high resis-tance (MIC≥16μg/mL) has been in creasing.A significant increase in EM resistance was observedover a10-year period.There were118 strains (15.6%) that persisted after treatment with β-lactams.In the past few years it has been discovered that someS. pyogenes can be internalized by human cellsof respiratory tract origin and survive within them.Since β-lactams do not reach high intracellularconcentrations, this ability of S.pyogenes may belatedtotreatmentfailre.Sicemacrolidescanentereukaryotic cells and remain active in intracellular compartments, they will beeffective for these S.pyogenes.In case of pharyngitis which againist treatment with β-lactams, there is a possibilitymacrolides are effective. Macrolidesmay be effective in pharyngitis resistant to treatment withβ-lactams. However, macrolide resistance is not rar, suscepti ility must be tested.

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In the 2004/05 influenza season there were epidemics of influenza caused by several types of vi-ruses (type B and A (H3) viruses, and type B, A (H3), and A (H1) viruses) in many areas of Japan.In such epidemics a single individual could be co-infected with several influenza viruses. From Feb-ruary to March in 2005, we examined 15 patients who were positive for influenza type A and B vi-ruses when tested with a rapid diagnostic kit.
The type A (H3) and B influenza virus genes were successfully amplified by RT-PCR in 10 of the15 patients, confirming that they were co-infected with type A (H3) and B viruses.The type A (H1) and B virus genes were successfully amplified in another patient, confirming that the patient was co-infected with type A (H1) and B viruses. By contrast, 2 patients were clearly positive for type A and B viruses according to the rapid diagnostic kit, but positive for type B virus alone by RT-PCR. No in-fluenza virus genes were detected by RT-PCR in the remaining 2 patients.
To isolate one type from a mixture of two different types of influenza viruses in a specimen, weneutralized one of the types with type-specific antiserum, and isolated the other with MDCK(+) cells. The results obtained by virus isolation were identical to those obtained by RT-PCR. Influenzaviruses corresponding to the results of RT-PCR were isolated from 9 of the 11 patients in which isola-tion was attempted. No viruses were isolated from the 2 patients in whom no virus genes were de-tectable by RT-PCR.
Based on these results we concluded that 11 of 15 patients who were positive for type A and Bviruses according to the rapid diagnostic kit were co-infected with type A (H3) or A (H1) and B virus.
When several types of influenza viruses are prevalent, as in the 2004/05 influenza season, thepossibility of a patient being co-infected with more than one type of influenza virus should be consid-ered.

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The propotions of resistant strains and sensitivity to oral antibacterial agents were determinedfor 468 strains of Streptococcus pneumoniae and 557 strains of Haemophilus influenzae isolated from pediatric outpatients with a respiratory tract infection at the first consultation at 20 medical institutionsnationwide in the predefined 4-week period during November 2002 and June 2003. PRSP of the S.pneumoniae strains, accounted for 27%, and BLNAR accounted for 35% of the H. influenzae strains.Against the S. pneumoniae strains, faropenem showed the best MIC₉₀ value, 0.5μg/mL, of the β-lactam antibacterial agents, followed by cefditoren-pivoxil, and among the macrolide and ketolide antibacterial agents, telithromycin showed the best MIC₉₀ value, 0.12μg/mL. Against the H. influenzae strains, cefditoren-pivoxil showed the best MIC₉₀ value, 0.25μg/mL, among the β-lactam antibacterial agents, and among the macrolide and ketolide antibacterial agents, azithromycin showed the best activity, followed by telithromycin. It seems necessary to take these results into consideration when choosing drugs for treatment.
It will be necessary to survey the trends in resistant strains and the clinical efficacy of various oral antibacterial agents in the future.

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We report a case of Yersinia pseudotuberculosis (Y. ptbc) infection complicated by disseminated intravascular coagulation (DIC) that presented as Kawasaki disease (KD).
A 9-year-old girl had been well until two days before, when she developed a fever, exanthem, and abdominal pain. An erythematous macular rash was observed in the perineum, and she had astrawberry tongue.
The patient was admitted to Kawasaki Medical School Hospital because the macular rashspread over her entire body, and edema of her hands and conjunctivitis subsequently developed.Echo cardiography showed dilation of the left coronary artery. Thrombocytopenia and an elevatedtotal fibrin degeneration product level were noted on the third hospital day, and the prothronmbinand partial-thromboplastin times were prolonged. Her clinical presentation was typical of KD and DIC. A stool culture and a blood culture were negative. Serologic tests were positive for antibodies to Y. ptbc. The antibody titer against Y. ptbc-derived mitogen was not elevated after her recovery.
Y. ptbc infection should be considered in an older child whose clinical findings fulfill the criteriafor KD complicated by DIC.

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