To evaluate the in vitro antimicrobial activities of biapenem, arbekacin, and cefminox against different gram-negative bacterial isolates in China, a total of 100 non-duplicated Escherichia coli, 100 Acinetobacter baumannii, 100 Pseudomonas aeruginosa, and 99 Klebsiella pneumoniae isolates were collected from 6 teaching hospitals in China in 2012. The minimal inhibitory concentrations (MICs) of biapenem, arbekacin, cefminox and 13 other antibiotics were determined by the broth microdilution method. The carbapenems (biapenem, meropenem, and imipenem) exhibited high antimicrobial activity against E. coli (98%) and K. pneumoniae (≥95%), followed by colistin and amikacin. The MIC₅₀ and MIC₉₀ of biapenem against E. coli were ≤0.06 mg/L and 0.25 mg/L, respectively. For K. pneumoniae, the MIC₅₀ and MIC₉₀ of biapenem were 0.25 mg/L and 1.0 mg/L, respectively. The MIC₅₀ and MIC₉₀ of cefminox against E. coli were 1.0 mg/L and 4.0 mg/L, respectively. The resistance rates of A. baumannii to most of the antibiotics were more than 50%, except for colistin. Amikacin was the most active antibiotic against P. aeruginosa (97%), followed by colistin (93%). The MIC₅₀ and MIC₉₀ of arbekacin against P. aeruginosa were 2.0 mg/L and 8.0 mg/L, respectively. In conclusion, carbapenems, colistin, amikacin, and arbekacin exhibited high antimicrobial activities against gram-negative bacteria, except A. baumannii.

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Multipurpose cohort studies have demonstrated that coffee consumption reduces the risk of hepatocellular carcinoma (HCC). Given that one of the main causes of HCC is hepatitis C virus (HCV) infection, we examined the effect of caffeic acid, a major organic acid derived from coffee, on the propagation of HCV using an in vitro naïve HCV particle-infection and production system within human hepatoma-derived Huh-7.5.1-8 cells. When cells were treated with 1% coffee extract or 0.1% caffeic acid for 1-h post HCV infection, the amount of HCV particles released into the medium at 3 and 4 days post-infection considerably decreased. In addition, HCV-infected cells cultured with 0.001% caffeic acid for 4 days, also released less HCV particles into the medium. Caffeic acid treatment inhibited the initial stage of HCV infection (i.e., between virion entry and the translation of the RNA genome) in both HCV genotypes 1b and 2a. These results suggest that the treatment of cells with caffeic acid may inhibit HCV propagation.

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In this study, we evaluated and compared the antibacterial activity of chlorine dioxide (ClO₂) and sodium hypochlorite (NaClO) on various multidrug-resistant strains in the presence of bovine serum albumin and sheep erythrocytes to mimic the blood contamination that frequently occurs in the clinical setting. The 3 most important species that cause nosocomial infections, i.e., methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Pseudomonas aeruginosa (MDRP), and multidrug-resistant Acinetobacter baumannii (MDRA), were evaluated, with three representative strains of each. At a 10-ppm concentration, ClO₂ drastically reduced the number of bacteria of all MDRP and MDRA strains, and 2 out of 3 MRSA strains. However, 10 ppm of NaClO did not significantly kill any of the 9 strains tested in 60 seconds (s). In addition, 100 ppm of ClO₂ completely killed all MRSA strains, whereas 100 ppm of NaClO failed to significantly lower the number of 2 MRSA strains and 1 MDRA strain. A time-course experiment demonstrated that, within 15 s, 100 ppm of ClO₂, but not 100 ppm of NaClO, completely killed all tested strains. Taken together, these data suggest that ClO₂ is more effective than NaClO against MRSA, MDRP, and MDRA, and 100 ppm is an effective concentration against these multidrug-resistant strains, which cause fatal nosocomial infections.

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Rhinovirus infections are common in all age groups world-wide, and they occur throughout the year. In this study, we examined 2,689 nasopharyngeal swabs collected in Mongolia during 2008–2013. Human rhinoviruses (HRVs) were detected in 295 (11.0%) samples, and 85 (28.8%) patients were co-infected with other respiratory viruses. HRV was co-detected with bocavirus, human coronavirus, and respiratory syncytial virus in 21 (24.7%), 17 (20.0%), and 14 (16.5%), respectively. We tested 170 (57.6%) of the 295 HRV-positive samples: 117 HRV strains were typed by using the VP4/VP2 method and 53 by using 5′ UTR method. We found HVR-A, HVR-C, and HVR-B infections in 80 (47.1%), 76 (44.7%), and 14 (8.2%) samples, respectively.

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Enhanced surveillance was conducted during the Sports Festival in Tokyo 2013 (September 28–October 14, 2013) for early detection of outbreaks of infectious diseases and other health emergencies. Through this enhanced surveillance, 15 cases were found that required additional gathering of information outside the routine process of creating/evaluating the Daily Report. However, none of these was assessed as critical. Through the enhanced surveillance, we structured a framework that allows for earlier response when detecting aberrations. It includes the role of the Tokyo Metropolitan Government in communications and contacts with relevant parties such as public health centers, as well as in monitoring of surveillance data. However, some issues need to be further considered toward the Tokyo 2020 Olympic and Paralympic Games, such as establishing the criteria for additional response steps, increasing the number of participating bodies in syndromic surveillance, and strengthening of cooperation with related departments, including those for crisis management assuming potential biological/chemical terrorism.

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Fever of unknown origin (FUO) poses a major diagnostic challenge in patients infected with human immunodeficiency virus (HIV). In this retrospective study, we sought to assess the clinical utility of percutaneous liver biopsy as a diagnostic aid for FUO in HIV-infected patients and identify the factors associated with a greater likelihood of a positive diagnostic yield form this procedure. A total of 101 HIV-infected patients with FUO, who had undergone percutaneous liver biopsy in an HIV care hospital, served as the study population. The results obtained from percutaneous liver biopsy were categorized into three groups: (i) diagnostic, (ii) helpful, and (iii) not helpful. Diagnostic and helpful results were classified as useful. The mean (SD) age of patients was 37.6 (6.9) years, and the median (interquartile range [IQR]) CD4 count was 18 (3–62) cells/mm³. The median (IQR) duration of fever was 20 (8–30) days. Percutaneous liver biopsy was diagnostic in 51 patients (50.5%), helpful in 12 (11.9%) and not helpful in 38 (37.6%) patients. On multivariate analyses, elevation of serum alkaline phosphatase level (OR 1.27 per one time elevation from the upper normal range; 95% CI, 1.03–1.57; P = 0.023), and fever duration of less than 3 weeks (OR 3.82; 95% CI, 1.03–14.18; P = 0.046) was significantly associated with the likelihood of the biopsy findings being classified as useful. Our study supports the case for percutaneous liver biopsy as a useful diagnostic aid in HIV-infected patients with FUO.

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“Immunological discordance,” i.e., immunological failure despite complete viral suppression in human immunodeficiency virus (HIV)-infected patients receiving antiretroviral therapy (ART), is associated with increased risk of AIDS or death. To evaluate risk factors for immunological discordance in a resource-limited setting in which patients usually present late with low CD4 cell counts, we conducted a case-control study among HIV-infected patients receiving ART and having undetectable HIV RNA. The study included patients with immunological discordance (cases), which was defined as CD4 cell count < 30% above baseline and absolute CD4 cell count < 200 cells/mm³ at the first 12 months of undetectable HIV RNA (<50 copies/mL). Patients without immunological discordance were included as controls. Of 142 patients (44 cases; 98 controls), the mean age was 38.6 ± 9.4 years and 67.6% were men; 65.5% had history of opportunistic infections. In multivariate analysis, only baseline CD4 cell count < 100 cells/mm³ (odd ratio [OR], 2.53; 95% confidence interval [CI], 1.04–6.14; P = 0.040) and history of lost to follow-up (OR, 11.04; 95% CI, 2.87–42.46; P < 0.001) were significantly associated with immunological discordance. Early initiation of ART and intervention to improve regular clinic visit compliance and adherence to ART are crucial to prevent immunological discordance among HIV-infected patients.

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Human immunodeficiency virus (HIV) tests are commonly performed in emergency departments (EDs) in the United States (US), but the experience and effectiveness of conducting rapid HIV tests in EDs in regions with low HIV seroprevalence outside the US have seldom been reported. An observational cross-sectional opt-in rapid HIV test and counseling program was conducted at an ED in a teaching hospital in Taiwan, a country with low seroprevalence, to determine the acceptance of rapid HIV tests as well as risky behaviors and illness presentations of people who agreed to undergo the tests. Among 7,645 ED patients between 20 and 55 years of age, 2,138 (28%) agreed to undergo rapid HIV tests, and only 2 (0.09%) tested positive. Patients diagnosed with urinary tract infections, respiratory tract infections, infectious diarrhea, and pelvic inflammatory disease were more likely to be willing to undergo rapid HIV tests in the ED. Stratified analysis revealed that sexually active patients were more likely to consent to HIV testing. Therefore, non-targeted opt-in HIV testing and counseling in the ED was feasible but was not effective in a region with low HIV seroprevalence.

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Herein, we determined the seroprevalence, seroconversion, and risk factors associated with Toxoplasma gondii (T. gondii) infection among pregnant women in Taipei, Taiwan. Pregnant women attending antenatal consultation in a Taipei medical center were invited, and 104 women completed a self-administered structured questionnaire. Venous blood samples were collected during the first and third trimester after consent was obtained. Serum IgG and IgM antibodies (Abs) as well as IgG avidity were analyzed using an enzyme-linked fluorescent assay. Of the samples collected in the first trimester, seven were seropositive for IgG Abs and one was seropositive for IgG + IgM Abs with a borderline avidity index, resulting in an overall seroprevalence of 7.7%. No statistically significant association was found between toxoplasmosis and age, pregnancy history, or any risk factors. Seroconversion was not detected from paired sera between the first and third trimesters. Pregnant women with senior high school education level or those who claimed to knowing Toxoplasma exhibited a significantly higher seroprevalence than those with bachelor degree (P = 0.05) or those who claimed not to have this knowledge (P = 0.05). Therefore, failure to understand the importance of T. gondii infection and the prevention measures resulted in the development of toxoplasmosis among these women.

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Polymyxins have recently reemerged as a treatment option in response to the increasing number of resistant bacterial infections seen in recent years. Therefore, the current study aimed to determine the rate of and risk factors related to colistin-associated nephrotoxicity. All adult patients who had received colistimethate sodium (CMS) between 2010 and 2012 and met the inclusion criteria were included in the study. RIFLE (Risk, Injury, Failure, Loss of renal function and End stage of renal disease) criteria were used to evaluate nephrotoxicity. Age, sex, underlying diseases presences, daily and total CMS doses, daily blood urea and creatinine levels, as well as concurrent drug use were recorded for each patient. Nephrotoxicity occurred in 48% of patients. There was a significant difference in the baseline serum urea levels of patients who experienced nephrotoxicity and those who did not (P value (P) = 0.015). Furthermore, the multivariate analysis showed that advanced age and concomitant aminoglycoside-class antibiotic use were significantly associated with nephrotoxicity. In conclusion, colistin should be used carefully, and all patients should be monitored closely for renal nephrotoxicity.

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In India, artemisinin-based combination therapy (ACT; specifically artesunate + sulfadoxine-pyrimethamine) has been implemented for uncomplicated falciparum malaria since 2010. But for vivax malaria drug policy remained unchanged i.e., chloroqine and primaquine. We observed the impact of this intervention in urban Kolkata by analyzing data from the Malaria Clinic from 2001 to 2013. In Kolkata, we observed that Plasmodium vivax was perennial, whereas P. falciparum infection was seasonal. Before ACT implementation, the proportion of P. falciparum was as high as 50% and it steadily decreased during 4 successive years post intervention. No change was observed in the number of P. vivax cases. ACT may be an effective measure in reducing falciparum malaria cases. Artemisinin-derivative combination therapies should be explored in vivax malaria to reduce the overall burden of malaria.

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We encountered a pediatric case of bacteremia and possible cholecystitis due to Moraxella osloensis that was treated successfully. We confirmed the diagnosis with the presence of a high serum titer of the antibody to the organism. Furthermore, 16S rRNA sequencing was performed to identify the bacteria.

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Since Group B Streptococcus (GBS, Streptococcus agalactiae) clinical isolates are believed to be uniformly susceptible to β-lactams, penicillin G has been used as the first-line agent for the prevention and treatment of GBS infections. However, the existence and characteristics of GBS isolates with reduced penicillin susceptibility (PRGBS) have recently been reported in Japan. Moreover, the sequence type (ST) 458 is predominant among the PRGBS in Japan. Although the majority of the PRGBS isolates in Japan have been recovered from respiratory specimens of adults, no information on the genotype of these isolates is available. Therefore, whether ST458 predominates among GBS isolates obtained from such specimens is not known. In this study, we characterized the STs of 38 penicillin-susceptible GBS isolates (PSGBS) recovered from respiratory specimens and compared them to the reported PRGBS STs. ST458, the predominant ST among the PRGBS isolates studied (10/19, 53%), was not found in the PSGBS isolates. Thirty-six PSGBS isolates belonged to the ST1/19/10 group (includes 6 different STs), and the remaining 2 isolates belonged to that of ST23. Further, the PRGBS isolates were divided into the ST1 (3 STs), and ST23 (2 STs) groups. ST458 was not predominant among the PSGBS isolates recovered from respiratory specimens in Japan and may therefore be specific to the PRGBS. Thus, the ST distribution of the PRGBS isolates does not reflect that of the PSGBS.

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Single nucleotide polymorphisms (SNPs) 1063A/G (Asp299Gly) and 1363C/T (Thr399Ile) in the gene encoding Toll-like receptor 4 (TLR4) increase susceptibility to invasive aspergillosis. However, limited information is available on the prevalence of these SNPs in Japan. Therefore, we surveyed these TLR4 SNPs by using formalin-fixed and paraffin-embedded tissue blocks obtained from autopsies of patients with invasive pulmonary aspergillosis. Tissue samples of approximately 30% patients were included in genomic analysis. However, none of these samples showed the presence of TLR4 Asp299Gly and Thr399Ile polymorphisms. Thus, the present study provided information on the prevalence of TLR4 SNPs in Japanese patients with invasive aspergillosis and indicated that these SNPs played a minor role in increasing the susceptibility of Japanese individuals to invasive aspergillosis.

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In this paper, we examine 2 case reports for different reptile-related Salmonella enterica subspecies enterica serotypes. In case 1, a 5-year-old boy presented with gastroenteritis caused by S. enterica subspecies enterica serovar Poona. The suspected source of infection was a turtle kept at the patient's home. In case 2, a 4-year-old boy presented with gastroenteritis caused by S. enterica subspecies enterica serovar Abony. The Pulsed-field gel electrophoresis analysis suggested that a tortoise kept at the patient's home was the source of infection. This paper presents a review of the literature and an examination of cases regarding turtle-associated salmonellosis in Japan.

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Clostridium difficile PCR ribotype 027 is a hypervirulent strain that has caused significant nosocomial diarrhea in many countries but has not yet been reported or isolated in Taiwan previously. Here, we present the characteristics of a case of C. difficile PCR ribotype 027 identified in Taiwan. Taiwan is located in a key transportation center of Asia. This report is important for alerting hospitals and public health departments in Asia about the emergence of this hypervirulent strain so that close monitoring may be enacted to prevent potential outbreaks.

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Lactococcus lactis is a gram-positive coccus that is nonpathogenic in humans. Herein, we present the case of a 1-year-old boy with Down syndrome and Hirschprung's disease (HD) who developed a catheter-related bloodstream infection with L. lactis after gastrointestinal surgery. The patient had been hospitalized in the pediatric surgery unit from birth because of HD, and had undergone the Duhamel-Martin procedure which caused recurrent diarrhea episodes and feeding intolerance. On the infant's 430th day of life, he had an episode of gastroenteritis and feeding intolerance. Because of clinical suspiction of sepsis, blood cultures were taken both from the central venous catheter and peripheral vein, and evidence of a growing microorganism was detected in 2 different central venous catheter blood cultures taken 2 days apart. The colonies were then identified by both the Vitek 2 and Vitek MS systems (bioMérieux, Marseille, France) as L. lactis spp. lactis. The central venous catheter could not be removed because of the absence of a peripheral venous line, and the patient was subsequently successfully treated with vancomycin. Therefore, although Lactococcus species is generally thought to be nonpathogenic, it should still be kept in mind as a potential pathogen in infants.

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Methylobacterium mesophilicum — is a gram-negative bacillus most often isolated in medical establishments. In humans, M. mesophilicum is considered a conditionally pathogenic flora. Infections in humans generally occur in immunodeficient individuals. This article describes a rare case of M. mesophilicum infection that developed into acute meningitis in a 26-year-old patient. Decreased neutrophil bactericidal activity was also detected. To our knowledge, there have been no previous reports of meningitis due to M. mesophilicum.

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Cholera is a major cause of illness in the developing world. During the monsoon season, small sporadic clusters of cholera cases are reported on an annual basis in Karnataka, India. During the monsoons of 2013, there was a cholera outbreak in Badami, a remote area of Bagalkot district in Karnataka. The multi-drug-resistant Vibrio cholerae O1 serotype Ogawa was found to be responsible for this outbreak. On 5 August 2013, a 30-year-old woman presented with severe dehydration and watery diarrhea at the Aganwadi Health Centre in Badami. A total of 49 suspected cholera cases were reported, with an attack rate of 3.5%. The V. cholerae isolates exhibited resistance to a wide range of drugs, including ampicillin, co-trimoxazole, nitrofurantoin, carbenicillin, and third generation cephalosporins, and showed reduced susceptibility to third generation fluoroquinolones. All of the cephalosporin-resistant V. cholerae strains produced extended-spectrum beta-lactamase. All V. cholerae O1 isolates harbored virulent genes (ctxA, ctxB, tcpA El Tor, Tox S, VPI, ToxT, ToxR, ToxRS, ace, zot, and tcpP) and were found to be genetically similar as determined by randomly amplified polymorphic DNA fingerprinting assay. To the best of our knowledge, this is the first report of a cholera outbreak in the district of Bagalkot. The resistance of V. cholerae to commonly used antimicrobial drugs is becoming a major public health concern in the region as clinicians are left with a limited choice of antibiotics for the treatment of cholera.

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Volume 68, no. 3, p. 176–180, 2015. Page 176, affiliation “¹Foodborne and Waterborne Diseases Research Center, Tehran; ²Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Tehran; ³Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran; and ⁴Gastroenterology and Liver Diseases Research center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran” should read “¹Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; ²Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; ³Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran; and ⁴Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran”

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