The present French and European measles outbreaks show a bimodal distribution: the two most affected populations are infants aged less than 1 year and adults older than 20 years. The purpose of this study was to determine wether there were differences in the clinical presentation and evolution of measles between adult and pediatric patients. We performed a retrospective study of adult and pediatric measles patients admitted to three tertiary-level university hospitals between January 2008 and May 2011. Data were extracted from medical charts and positive laboratory results. Collected data were age, sex, geographical origin, vaccination status, source of exposure, overseas travel before symptom onset, clinical symptoms, risk factors for complications, severity criteria on admission, type of diagnosis, biological abnormalities, complications, and treatments. A total of 305 patients (171 children and 134 adults) were included in the study. The mean age was 4.6 ± 4.4 years in children and 26.7 ± 8.1 years in adults. Children were less often hospitalized than adults (29% vs. 66%). A comparison between hospitalized pediatric (n = 49) and adult (n = 89) patients revealed that the former had a higher incidence of complications (P < 0.0001), more otorhinolaryngological complications (24% vs. 1%; P < 0.0001), and a higher incidence of severe criteria on admission (P = 0.02). Hospitalized pediatric patients differed from adults in terms of disease severity and complications.

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Enterotoxigenic Escherichia coli (ETEC) is the most common cause of diarrhea among children. ETEC strains express colonization factors (CFs), which mediate adherence to the small intestinal epithelium and produce entrotoxins that induce diarrhea. Here, we characterized the phenotypes and genotypes of ETEC strains from 261 diarrheal stool samples from Iranian children. The prevalence of ETEC was 8.04%. Most of the isolates were positive for heat-labile and heat-stable toxins. CFA/I, CS3, CS2, and CS5 were detected from some of the clinical isolates. 33.3% of the isolates did not express CFs. The majority of ETEC isolates were identified as O127 and O128 serotypes, and 57% of the strains were resistant to more than 1 antimicrobial agent. Heat-labile enterotoxin activity was confirmed using the Y1 adrenal cell assay, rabbit ileal loop and adenylate cyclase activation tests. Regional phenotypic and genotypic characterization could help to elucidate the ecology and pathogenicity of ETEC to efficiently reduce the burden of illness brought about by ETEC. This study may lead to development of effective prophylactic measures.

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The mechanisms of endothelial barrier dysfunction in dengue disease remain poorly understood. Endothelial cell (EC) death due to virus infection or in combination with an infection-induced cytokine storm is deemed as one of the major causes of plasma leakage. Using an in vitro model of human endothelia and several dengue virus (DENV) strains (including a clinical isolate), the direct consequence of infection on endothelial permeability was investigated throughout the course of the infection. All employed DENV-2 strains were able to infect and replicate in ECs. Rather than increase endothelial permeability, DENV infection alone enhanced cell barrier integrity up to 7 days postinfection. Improved cell barrier function was mediated by type I interferon activation at the early phase of infection and by the survival advantage of the infected cells at the late phase of infection. Consistent with this phenomenon, DENV infection did not augment tumor necrosis factor-α-induced permeability. Our results prove that DENV infection does not directly account for vascular permeability; DENV neither induces hyperpermeability nor exacerbates the permeabilizing effect of cytokines. The contributory role of other factors on plasma leakage during dengue disease warrants further investigation.

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A matched case-control study was conducted in Beijing to identify the relative importance of major environmental risk factors for outbreaks of hand, foot, and mouth disease (HFMD). A case was defined as a kindergarten class with at least 1 HFMD outbreak. As a control, a kindergarten class that did not experience an HFMD outbreak was used. To identify potential transmission factors, the control group was divided into 2 subgroups: a sporadic group and an HFMD-negative group. We collected data for 8 environmental factors and basic information of each class. The correlations between the suspected environmental factors and HFMD outbreaks were analyzed. Thirty outbreak classes, 19 sporadic classes, and 30 HFMD-negative classes were enrolled. Class grade, indoor solar radiation, and ultraviolet (UV) radiation revealed significant differences among the 3 groups. After controlling for other factors, UV radiation (adjusted β = −0.42) and class grade (adjusted β = −0.46) as protective factors and temperature (adjusted β = 0.31) as a risk factor were significantly associated with the attack rate by multiple linear regression analysis. Logistic regression analysis showed that the probability of an HFMD outbreak in the lower grade was 6-fold greater than that in the higher grade (P = 0.0380, odds ratio = 0.157, 95% confidence interval = 0.027–0.903). We identified UV radiation and class grade as protective factors that were associated with the epidemic intensity in Beijing. However, more data is needed to evaluate the relationship between these factors and HFMD outbreaks.

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The recent H1N1 influenza pandemic involved several cases of influenza pneumonia. Although influenza pneumonia may have occurred more frequently in fatal cases, the clinical characteristics of influenza pneumonia in Japan remain unclear. We conducted a retrospective cohort study of adult patients with influenza pneumonia, for which questionnaires were sent to respiratory physicians working in 2,491 hospitals across Japan. Questionnaires were returned by 994 physicians (39.9%), providing data on 346 influenza pneumonia cases. The case-fatality ratio was 8.2% (27 cases). Pure influenza viral pneumonia was observed in 94 cases, which were most frequently young adults with chief complaints of non-productive cough and dyspnea. Radiological imaging showed diffuse ground-glass opacity. Corticosteroid therapy and mechanical ventilation were more frequently used for pure influenza viral pneumonia, but these modalities were not correlated with poor treatment outcomes. Anti-influenza antiviral drugs were prescribed in 335 cases (96.8%). In the recent pandemic in Japan, several pure influenza viral pneumonia cases were observed, but we found no variances in mortality between the different types of pneumonia. Almost all cases were treated with anti-influenza antiviral drugs, which may have contributed to its relatively low mortality rate.

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Human adenovirus (HAdV) serotype 7 is an important etiological agent of severe childhood pneumonia. The aim of this study was to define the role of HAdV7 and to describe its clinical and molecular epidemiological characteristics in the Philippines in 2011. HAdVs were detected by viral culture, and a partial region of hexon gene was sequenced. A total of 700 patients were enrolled, of which 22 (3.1%) died. Nine (1.3%) HAdV cases were confirmed, of which 7 were positive for HAdV7, 1 for HAdV3, and 1 for HAdV5. Among the 9 HAdV-positive cases, 4 (44%) with HAdV7 died. Molecular analysis revealed that all HAdV7 isolates were closely related to genome type h strains. This study demonstrated the significance of HAdV7 as an etiological agent of severe pediatric pneumonia with a high fatality rate. Hence, continuous monitoring is required to define the clinical and public health significance of HAdV7 infection.

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A total of 138 animals from 7 species (Apodemus agrarius, Bandicota indica, Crocidura suaveolens, Mus caroli, Mus formosanus, Rattus losea, and Suncus murinus) captured in Taichung, located in central Taiwan, and Kinmen Island, an island off the shore of China, were examined for the presence of Anaplasma phagocytophilum. The presence of the bacteria, which causes human granulocytic anaplasmosis, was examined by nested PCR targeting the16S rDNA. Twelve animals (8.7%) from M. caroli and R. losea, and 25 (18.1%) from A. agrarius, B. indica, M. caroli, and R. losea were infected with A. phagocytophilum and Anaplasma bovis, respectively. Phylogenetic analysis revealed that partial 16S rDNA sequences in the 12 aforementioned animals showed higher similarity to the sequences related to A. phagocytophilum detected in wild rodents (Rattus and Niviventer) from southeast China. The sequences of the other 25 animals belonged to the A. bovis clade. We demonstrated that small wild mammals were infected with A. phagocytophilum and A. bovis in Taichung and Kinmen Island, Taiwan.

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A 34-year-old woman presented with septic shock, disseminated intravascular coagulation (DIC), and multiorgan dysfunction with a 1-week history of fever, abdominal pain in the right upper quadrant, and dull pain in the right flank. Physical and laboratory data showed cytopenia (thrombocytopenia and anemia), splenomegaly, hyperferritinemia, hypofibrinogenemia, and an elevated level of interleukin-2 receptor (soluble CD25). Bone marrow examinations disclosed hypercellular marrow with increased infiltration of histiocytes with hemophagocytosis. This diagnosis was confirmed by positive Weil–Felix test results (Proteus mirabilis OX-K titer, 1:80), the presence of IgG and IgM antibodies, and positive PCR results for Orientia tsutsugamushi. The patient developed a severe intracranial hemorrhage 3 days after admission and expired due to systemic inflammatory response syndrome with DIC and multiorgan failure on the 13th day of hospitalization. Scrub typhus with hemophagocytic syndrome can be complicated by DIC and multiorgan failure. Patients with scrub typhus usually have an excellent response to treatment; therefore, early diagnosis and prompt administration of antimicrobial therapy may prevent the development of serious complications.

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This study aimed at evaluating the effectiveness of testing multiple samples (urine, stool, and pharyngeal swabs) for accurate screening of multidrug-resistant (MDR) Pseudomonas aeruginosa. Of a total of 641 patients, 16 (2.5%) were confirmed for MDR P. aeruginosa carriage at any site (urine and/or stool and/or pharyngeal swab). Notably, of the 3 sample sites, urine culture had the highest rate of positive surveillance for MDR P. aeruginosa. Seven (43.8%) of the 16 cases of MDR P. aeruginosa were detected by urine culture alone. Eleven (91.7%) of the 12 MDR P. aeruginosa carriers detected by urine culture had an indwelling urinary catheter. Our data suggest that urine culture was the most effective in detecting MDR P. aeruginosa carriage, particularly for patients with an indwelling urinary catheter. However, sample cultures from all 3 sites increased the detection rate of MDR P. aeruginosa carriage. Therefore, we recommend the use of a urine culture in combination with either a stool and/or a pharyngeal swab culture to increase the accuracy of MDR P. aeruginosa carriage detection.

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OXA-48 carbapenemase-producing organisms have emerged rapidly worldwide and may be transmitted through patients who receive medical care abroad. To our knowledge, this is the second case of OXA-48-producing Klebsiella pneumoniae isolated from a patient who had returned to Japan after receiving treatment abroad.

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Orientia tsutsugamushi remains latent in humans after scrub typhus. Pneumonia occurs as a complication of scrub typhus in the late-phase disease. However, pneumonia may also occur as a presenting manifestation of O. tsutsugamushi infection. We reviewed the cases of 3 patients with atypical pneumonia who presented at our hospital and were later confirmed to have O. tsutsugamushi infection by serology, nested polymerase chain reaction (PCR), and cell culture. All patients were young adults with no history of scrub typhus, and none claimed to have recently been exposed to areas where scrub typhus is endemic. Two cases occurred in non-outbreak seasons. Furthermore, eschar was not observed. Pneumonia was documented within 4 days after fever onset. The immunoglobulin (Ig) G antibody titers against O. tsutsugamushi were higher than the IgM titers, although the serologic test results were less helpful in the diagnosis. Nested PCR and cell culture of blood specimens confirmed the diagnosis of O. tsutsugamushi infection. These findings suggest that pneumonia can occur as a result of recrudescence of latent O. tsutsugamushi infection.

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Reverse transcription polymerase chain reaction (RT-PCR) and real-time RT-PCR were used to detect 14 (6.6%) influenza C virus (InfC) among 213 clinical samples collected from children with respiratory symptoms in Mie Prefecture, Japan, between January 2012 and December 2012. Virus isolation using Madin-Darby canine kidney cells and/or embryonated chicken eggs was also successful for 3 of the 14 PCR-positive samples. Eleven patients (78.6%) were aged <3 years. Phylogenetic analysis of the hemagglutinin-esterase gene showed that the InfC detected in Mie Prefecture belonged to the C/Sao Paulo/82-related lineage. To determine the seroprevalence of InfC, a total of 575 serum samples from patients aged 1 month to 69 years in Mie Prefecture were screened by hemagglutination inhibition test using the C/Mie/199/2012 (C/Sao Paulo/82-related lineage) strain as the antigen. The samples with an antibody titer of ≥1:16 were designated as antibody-positive. The results showed that 53.7% of the 296 serum samples collected in 2011 and 85.3% of the 279 samples collected in 2012 were positive for antibodies against InfC, suggesting that an outbreak of InfC infection occurred in Mie Prefecture in 2012. Therefore, continuous and proactive monitoring is important to determine the number of InfC-infections and to better understand the epidemiology.

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Dengue fever (DF) and dengue hemorrhagic fever (DHF) are caused by mosquito-borne dengue virus (DENV) infection leading to death in tropical and subtropical countries. In Thailand, all 4 serotypes of DENV are circulating. The most severe cases of DF and DHF are primarily introduced by secondary infections. Epidemiological studies have demonstrated that approximately 20% of the primary infection cases were caused by DENV-1 and -3, while the cases of DENV-2 or -4 accounted for less than 3%. For this reason, DENV-2 and -4 from primary infections have not been well studied. In this study, the sequence diversity of the envelope gene of 8 DENV-2 clinical isolates from primary/secondary infections was analyzed. DENV-2 from primary infections were highly heterogeneous in individual patients, whereas those from secondary infections were homogeneous. Phylogenetic analysis demonstrated that the heterogeneous population of DENV-2 from primary infections was composed of closely related quasispecies. Homogenous DENV-2 could be derived from selection of a particular viral population in secondary infections. The degree of sequence diversity of DENV-2 varied, and thus quasispecies may be involved in the progression of DENV infection.

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