Dengue virus (DENV) infection is a serious global health threat. For the surveillance and control of dengue, there is a need for robust diagnostic tools that are relatively easy to use and reliable in various clinical settings. We investigated the applicability of NS1 antigen detection in urine samples for the diagnosis of DENV. About 118 urine samples, obtained from 96 dengue patients at various phases of disease, were used for this study. NS1 antigen was detected by ELISA in the urine samples obtained from patients after 2–17 days of disease onset. Positive detection rates of NS1 antigen ranged between 13–43%. Based on real-time RT-PCR, positive detection rates of viral genome in the urine samples ranged between 20–33% on days 0 to ≥15. On days 11 to ≥15 after the disease onset, NS1 antigen was detected at similar rates in serum and urine samples. Additionally, NS1 antigen was detected in 2 urine samples, but not in the serum samples, on days 7 and 16 after the onset of the disease. The results confirm the applicability of NS1 antigen detection in urine samples using ELISA to diagnose acute DENV infection and suggests that the assay is potentially useful when only limited amounts of serum samples are available and in limited resource settings.

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Stigma, considered a social disease, is more apparent in developing societies which are driven by various social affairs, and influences adherence to treatment. The aim of the present study was to examine levels of social stigma related to tuberculosis (TB) in sociodemographic context and identify the effects of sociodemographic factors on stigma. The study sample consisted of 372 TB patients. Data were collected using stratified sampling with simple random sampling techniques. T tests, chi-square tests, and binary logistic regression analysis were performed to examine correlations between stigma and sociodemographic variables. Approximately 85.9% of patients had experienced stigma. The most frequent indicator of the stigma experienced by patients involved problems taking part in social programs (79.5%). Mean levels of stigma were significantly higher in women (55.5%), illiterate individuals (60.8%), and villagers (60.8%) relative to those of other groups. Chi-square tests revealed that education, monthly family income, and type of patient (pulmonary and extrapulmonary) were significantly associated with stigma. Binary logistic regression analysis demonstrated that stigma was influenced by sex, education, and type of patient. Stigma is one of the most important barriers to treatment adherence. Therefore, in interventions that aim to reduce stigma, strong collaboration between various institutions is essential.

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The level of osteopontin (OPN) increases during bacterial lung infection. However, the OPN level in virus-induced lung injury is unclear, and the relationship between the hyer-production of OPN and lung injury remains to be thoroughly understood. Therefore, we sought to determine whether a relationship exists between OPN and pulmonary damage. Particularly, pulmonary edema and the destruction of pulmonary tissue. In this study, we found that the OPN level was significantly elevated in patients with pulmonary damage, and there was a positive correlation between the OPN serum level and disease severity in influenza lung injury. The epithelial sodium channel (ENaC) is the main mechanism of clearance of pulmonary edema fluid, and matrix metalloproteinase 7 (MMP7) can degrade the extracellular matrix. In lung epithelial cells, OPN markedly decreased the mRNA expression of the α-subunit of ENaC through integrin β3 and CD44 (OPN receptors); however, the expression of MMP7 was promoted by OPN interaction with integrin β1 and CD44. In addition, OPN increased the levels of tumor necrosis factor-α and interleukin-6. These findings suggested that OPN might increase influenza virus-induced lung injury by augmenting lung epithelial cell apoptosis and impairing ENaC and extracellular matrix destruction.

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Nanotechnology is important for medical diagnosis. Various nanoparticles have presented tremendous potential for diagnosing disease markers, pre-cancerous cells, fragment of viruses, specific proteins, antibodies, and other disease indicators. In general, nanoparticles are smaller than 1,000 nm and produced from different materials in different shapes such as spheres, rods, wires, and tubes. Our study aimed to develop a novel antigen-capture immunoassay based on IgG polyclonal antibody-coated magnetic microbead nanoparticles for the rapid detection of circulating surface antigen 1 of Toxoplasma gondii in human serum samples. Sandwich ELISA elicited a sensitivity of 92%, a specificity of 92.7%, a positive predictive value (PPV) of 92%, and a negative predictive value (NPV) of 92.7%. Immunomagnetic bead-ELISA showed sensitivity (98%), specificity (96.4%), PPV (96%), and NPV (98.1%) higher than that of sandwich ELISA. It is obvious that the use of magnetic microbead nanoparticles offers the potential advantage of improving the diagnostic testing of toxoplasmosis.

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Treponema pallidum, hepatitis C virus (HCV), human immunodeficiency virus (HIV)-1, and hepatitis B virus (HBV) are major causes of sexually transmitted diseases passed through blood contact. The development of a sensitive and efficient method for detection is critical for early diagnosis and for large-scale screening of blood specimens in China. This study aims to establish an assay to detect these pathogens in clinical serum specimens. We established a TaqMan-locked nucleic acid (LNA) real-time polymerase chain reaction (PCR) assay for rapid, sensitive, specific, quantitative, and simultaneous detection and identification. The copy numbers of standards of these 4 pathogens were quantified. Standard curves were generated by determining the mean cycle threshold values versus 10-fold serial dilutions of standards over a range of 10⁶ to 10¹ copies/μL, with the lowest detection limit of the assay being 10¹ copies/μL. The assay was applied to 328 clinical specimens and compared with enzyme-linked immunosorbent assay (ELISA) and commercial nucleic acid testing (NAT) methods. The assay identified 39 T. pallidum-, 96 HCV-, 13 HIV-1-, 123 HBV-, 5 HBV/HCV-, 1 T. pallidum/HBV-, 1 HIV-1/HCV-, and 1 HIV-1/T. pallidum-positive specimens. The high sensitivity of the assay confers strong potential for its use as a highly reliable, cost-effective, and useful molecular diagnostic tool for large-scale screening of clinical specimens. This assay will assist in the study of the pathogenesis and epidemiology of sexually transmitted blood diseases.

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The first cases of Hantavirus infection in Turkey were reported in early 2009 in the Zonguldak and Bartin provinces. The aim of this study was to investigate the presence of Hantavirus antibodies in patients who had clinical and laboratory findings that were potentially associated with Hantavirus infection prior to the epidemic in Bartin in 2009. After screening 314,577 medical records from between 2007 and 2009, the clinical and laboratory data for 442 patients meeting the criteria of coexistent thrombocytopenia, and elevated urea and creatinine levels were transferred to a statistical program. Home visits were made to 170 patients, 84 of whom consented to participate in the study. The participants completed a questionnaire and provided a blood sample. Commercial anti-Hantavirus IgG and IgM ELISA and immunoblotting assays were used, with seropositive samples being confirmed by focus reduction neutralization tests (FRNT). ELISA and/or immunoblotting assays detected 10 positive samples; however, only 7 of these were recorded as positive by FRNT. FRNT positivity was significantly associated with female sex, the presence of a barn near to the house, and working in a forest (P < 0.05). In a Hantavirus endemic region, physicians must keep in mind that thrombocytopenia, and elevated urea and creatinine levels may indicate Hantavirus infection.

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Helicobacter pylori and hepatitis A virus (HAV) are thought to have similar routes of transmission and epidemiology. This study investigated the seroprevalence of these 2 pathogens among children in rural, central Taiwan. Serum samples were collected from 856 children between 2010 and 2012 and levels of anti-HAV and anti-H. pylori antibodies were measured by ELISA. Questionnaires were used to investigate possible risk factors. The overall H. pylori and HAV infection rates were 6% and 0.8%, respectively. There was a significant difference in H. pylori infection rates (P value=0.008), but not HAV infection rates, between different age groups. H. pylori infection rates were significantly higher in children whose mothers had lower education levels. In contrast, HAV infection rates were significantly higher in children whose fathers had lower education levels. The risk of HAV infection was also 14.20-fold higher in children whose family members had traveled to China or Southeast Asia. No significant correlation was found between H. pylori and HAV seropositivity. The seroprevalences of H. pylori and HAV were low in rural central Taiwan. Universal HAV vaccination is highly recommended to prevent outbreak due to low seroprevalence.

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Hand, foot and mouth disease (HFMD), caused by various viral pathogens, is an emerging infectious disease in children in Asia. Understanding the composition of these pathogens is necessary to prevent and control this disease. In the present study, the pathogens in 436 HFMD patients (from 2009 to 2011) with concurrent clinical indications of encephalitis, meningoencephalitis, or both, were defined using the semi-nested PCR. A systematic analysis of the composition of these pathogens was performed. Various enteroviruses that are capable of inducing central nervous system (CNS) damage in HFMD patients were identified, including enterovirus 71, coxsackievirus A16, and Echovirus 9. Most of these pathogens were found co-infecting the patients. The composition of the pathogens that induced CNS damage in the HFMD patients was dynamically modulated in the cases.

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Crimean-Congo hemorrhagic fever (CCHF) is a potentially fatal disease which is endemic to Turkey. We aimed to investigate the procalcitonin levels and their prognostic value over fatality in CCHF patients. The sera were harvested from patients who were diagnosed with CCHF within the first 2 days of the onset of their symptoms. The patients were divided into 2 groups according to their survival status: fatal or non-fatal. The biochemical and hematological parameters were studied in the Biochemistry Laboratory of Sorgun City Hospital. The sera were stored at −80℃ until testing for procalcitonin, and the procalcitonin levels were assayed by ELISA at the Biochemistry Laboratory of Kirikkale University. Forty- eight patients were included in the study, with 8 and 40 patients in the fatal and non-fatal groups, respectively. While the procalcitonin level was high in all patients in the fatal group, the same was observed in 30 patients in the non-fatal group (75%). The mean value of procalcitonin was 1.12 ng/ml in the fatal group and was 0.21 ng/ml in the non-fatal group (P = 0.003). According to the results of our study, the procalcitonin levels in the first 2 days of the onset of the symptoms might be helpful for predicting fatality in CCHF patients.

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In June 2013, a diarrheal outbreak occurred among high school students in Incheon, South Korea. We investigated the outbreak to identify the pathogen and mode of transmission. A case-control study using a self-administered questionnaire was conducted by local authorities and the Korean Centers for Disease Control and Prevention. Bacterial cultures of stool samples, environmental samples, and samples of preserved food items were prepared. PCR, serotyping, and pulsed-field gel electrophoresis (PFGE) were used to identify and characterize the outbreak-related pathogen. We identified 54 cases of gastroenteritis, with symptoms including diarrhea, abdominal pain, and nausea. None of the food items served in the high school cafeteria were significantly associated with illness, although the odds ratio for kippered trotters mixed with vegetables was relatively high (odds ratio: 2.92, 95% confidence interval: 0.62–13.69). Enteroaggregative Escherichia coli (EAEC) was isolated from this item and the stool samples from 22 symptomatic students and 4 asymptomatic food handlers. The PFGE patterns of EAEC isolated from these sources were indistinguishable. This outbreak was caused by EAEC, and kippered trotters mixed with vegetables, perhaps contaminated by asymptomatic food handlers, were linked to the outbreak. This case-control study highlights the importance of safe food preparation.

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Nontuberculous mycobacteria (NTM) are associated with a number of clinical diseases and only a few antitubercular agents are active against them. Oxazolidinones comprise a novel class of antimicrobials that inhibit bacterial protein synthesis at the ribosome. Linezolid, the first oxazolidinone antibacterial agent approved for clinical use, has excellent activity against some NTM but is ineffective against others. Sy142 and sy144 are novel oxazolidinones with demonstrated activties against Mycobacterium tuberculosis and Staphylococcus aureus. In this work, we compared the susceptibilities of key NTM species to linezolid, sy142, and sy144. The organisms included 21 isolates of Mycobacterium abscessus, 31 of Mycobacterium avium, 11 of Mycobacterium chelonae, 24 of Mycobacterium fortuitum, 26 of Mycobacterium kansasii, and 17 of Mycobacterium intracellulare. For M. kansasii and M. fortuitum, linezolid showed excellent antimicrobial activity, and an equal MIC range was found in sy142 and sy144. For the species that linezolid was less active against, sy142 and sy144 showed greater antimicrobial activities or exhibited equal compared to linezolid. Particularly, for M. avium and M. intracellulare, the in vitro antimicrobial activity of sy142 was 4-fold higher than that of linezolid. These results demonstrate the potential of these compounds to treat NTM infections.

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Previously, we conducted a 3-year prospective study to determine the viral causes of acute respiratory tract infections among 495 febrile pediatric outpatients. We collected 495 nasopharyngeal aspirate specimens, and used both real-time PCR assays and viral culture to test each for respiratory viruses other than coronavirus. Here, we used real-time PCR to test the 495 archival specimens for four human coronavirus strains. We identified 15 coronavirus-positive specimens: eight with OC43, 5 with NL63, 2 with HKU1, and none with 229E. Of the 15 children (5 boys) infected with human coronavirus, the mean age was 3.5 years, and the age range was 1.1 to 5.8 years; one child was diagnosed with lower respiratory infection; the other 14 were diagnosed with upper respiratory infection. Of these 15 patients, none were hospitalized, 5 were infected with coronavirus alone, 8 were co-infected with another virus, and 2 were co-infected with 2 other viruses. The multi-virus infections involved 6 adenoviruses, 3 respiratory syncytial viruses, 2 parainfluenza viruses, and 1 rhinovirus. In conclusion, the burden of human coronaviruses was relatively light among this cohort of 495 pediatric outpatients, and the incidence of these infections was low.

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Here, we report a case of pneumonia possibly caused by the aspiration of runoff water containing Chromobacterium haemolyticum. A 69-year-old man became intoxicated with alcohol, fell into a ditch, and lost consciousness after suffering a blow to the head. The lower half of his body was completely paralyzed because of damage to his spinal cord, and he aspirated runoff water from the ditch. Chest computed tomography scans revealed consolidation in the right upper lobe and bilateral lower lobes. A sputum culture detected gram-negative bacteria that was identified as C. haemolyticum. Antibacterial chemotherapy was initiated, and the clinical course was favorable. To the best of our knowledge, this is the first report of C. haemolyticum pneumonia in the literature.

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