Trends in the detection of viruses causing gastroenteritis over a 10-year period and impact of nonpharmaceutical interventions.

BACKGROUND: Viral gastroenteritis continues to be a leading cause of death in low-income countries. The impact of nonpharmaceutical interventions (NPIs) on the transmission of gastroenteritis-causing viruses during the COVID-19 pandemic is understudied. OBJECTIVES: To investigate the 10-year trends of enteric viruses and estimate the impact of implementing and mitigating NPIs. STUDY DESIGN: Data regarding norovirus, rotavirus, adenovirus, astrovirus, and sapovirus detection were collected from five Korean hospitals between January 2013 and April 2023. We compared positivity between the pre-pandemic, pandemic, and post-pandemic periods. The causal effects of implementing and mitigating NPIs were quantified using the Bayesian Structural Time Series (BSTS) model. RESULTS: Norovirus was most frequently detected (9.9 %), followed by rotavirus (6.7 %), adenovirus (3.3 %), astrovirus (1.4 %), and sapovirus (0.6 %). During the pandemic, the positivity of all five viruses decreased, ranging from -1.0 % to -8.1 %, with rotavirus showing the greatest decrease. In the post-pandemic period, positivity rebounded for all viruses except for rotavirus. The BSTS model revealed that NPI implementation negatively affected the detection of all five viruses, resulting in reductions ranging from -73.0 % to -91.0 % compared to the prediction, with rotavirus being the least affected. Conversely, NPI mitigation positively affected the detection of all viruses, ranging from 79.0 % to 200.0 %, except for rotavirus. CONCLUSIONS: Trends observed over 10 years show that NPIs have had a major impact on changes in enteric virus detection. The effect of vaccines, in addition to NPIs, on rotavirus detection requires further investigation. Our findings emphasize the importance of NPIs in infection control and prevention.

Unveiling the inhibition mechanism of Clostridioides difficile by Bifidobacterium longum via multiomics approach.

Antibiotic-induced gut microbiota disruption constitutes a major risk factor for Clostridioides difficile infection (CDI). Further, antibiotic therapy, which is the standard treatment option for CDI, exacerbates gut microbiota imbalance, thereby causing high recurrent CDI incidence. Consequently, probiotic-based CDI treatment has emerged as a long-term management and preventive option. However, the mechanisms underlying the therapeutic effects of probiotics for CDI remain uninvestigated, thereby creating a knowledge gap that needs to be addressed. To fill this gap, we used a multiomics approach to holistically investigate the mechanisms underlying the therapeutic effects of probiotics for CDI at a molecular level. We first screened Bifidobacterium longum owing to its inhibitory effect on C. difficile growth, then observed the physiological changes associated with the inhibition of C. difficile growth and toxin production via a multiomics approach. Regarding the mechanism underlying C. difficile growth inhibition, we detected a decrease in intracellular adenosine triphosphate (ATP) synthesis due to B. longum-produced lactate and a subsequent decrease in (deoxy)ribonucleoside triphosphate synthesis. Via the differential regulation of proteins involved in translation and protein quality control, we identified B. longum-induced proteinaceous stress. Finally, we found that B. longum suppressed the toxin production of C. difficile by replenishing proline consumed by it. Overall, the findings of the present study expand our understanding of the mechanisms by which probiotics inhibit C. difficile growth and contribute to the development of live biotherapeutic products based on molecular mechanisms for treating CDI.

Exploration of Potential Breath Biomarkers of Chronic Kidney Disease through Thermal Desorption-Gas Chromatography/Mass Spectrometry.

Breath volatile organic compound (VOC) analysis is a non-invasive tool for assessing health status; the compositional profile of these compounds in the breath of patients with chronic kidney disease is believed to change with decreasing renal function. We aimed to identify breath VOCs for recognizing patients with chronic kidney disease. Using thermal desorption-gas chromatography/mass spectrometry, untargeted analysis of breath markers was performed using breath samples of healthy controls (n = 18) versus non-dialysis (n = 21) and hemodialysis (n = 12) patients with chronic kidney disease in this cross-sectional study. A total of 303 VOCs alongside 12 clinical variables were used to determine the breath VOC profile. Metabolomic analysis revealed that age, systolic blood pressure, and fifty-eight breath VOCs differed significantly between the chronic kidney disease group (non-dialysis + hemodialysis) and healthy controls. Thirty-six VOCs and two clinical variables that showed significant associations with chronic kidney disease in the univariate analysis were further analyzed. Different spectra of breath volatile organic compounds between the control and chronic kidney disease groups were obtained. A multivariate model incorporating age, 2-methyl-pentane, and cyclohexanone showed high performance (accuracy, 86%) in identifying patients with chronic kidney disease with odds ratios of 0.18 (95% CI, 0.07-2.49, p = 0.013); 2.10 (0.94-2.24, p = 0.025); and 2.31 (0.88-2.64, p = 0.008), respectively. Hence, this study showed that renal dysfunction induces a characteristic profile of breath VOCs that can be used as non-invasive potential biomarkers in screening tests for CKD.

Two Years of Experience and Methodology of Korean COVID-19 Living Clinical Practice Guideline Development.

BACKGROUND: In Korea, during the early phase of the coronavirus disease 2019 (COVID-19) pandemic, we responded to the uncertainty of treatments under various conditions, consistently playing catch up with the speed of evidence updates. Therefore, there was high demand for national-level evidence-based clinical practice guidelines for clinicians in a timely manner. We developed evidence-based and updated living recommendations for clinicians through a transparent development process and multidisciplinary expert collaboration. METHODS: The National Evidence-based Healthcare Collaborating Agency (NECA) and the Korean Academy of Medical Sciences (KAMS) collaborated to develop trustworthy Korean living guidelines. The NECA-supported methodological sections and 8 professional medical societies of the KAMS worked with clinical experts, and 31 clinicians were involved annually. We developed a total of 35 clinical questions, including medications, respiratory/critical care, pediatric care, emergency care, diagnostic tests, and radiological examinations. RESULTS: An evidence-based search for treatments began in March 2021 and monthly updates were performed. It was expanded to other areas, and the search interval was organized by a steering committee owing to priority changes. Evidence synthesis and recommendation review was performed by researchers, and living recommendations were updated within 3-4 months. CONCLUSION: We provided timely recommendations on living schemes and disseminated them to the public, policymakers and various stakeholders using webpages and social media. Although the output was successful, there were some limitations. The rigor of development issues, urgent timelines for public dissemination, education for new developers, and spread of several new COVID-19 variants have worked as barriers. Therefore, we must prepare systematic processes and funding for future pandemics.

Melatonin and Prostate Cancer: Anti-tumor Roles and Therapeutic Application.

Melatonin is an endogenous indoleamine that has been shown to inhibit tumor growth in laboratory models of prostate cancer. Prostate cancer risk has additionally been associated with exogenous factors that interfere with normal pineal secretory activity, including aging, poor sleep, and artificial light at night. Therefore, we aim to expand on the important epidemiological evidence, and to review how melatonin can impede prostate cancer. More specifically, we describe the currently known mechanisms of melatonin-mediated oncostasis in prostate cancer, including those that relate to the indolamine's ability to modulate metabolic activity, cell cycle progression and proliferation, androgen signaling, angiogenesis, metastasis, immunity and oxidative cell status, apoptosis, genomic stability, neuroendocrine differentiation, and the circadian rhythm. The outlined evidence underscores the need for clinical trials to determine the efficacy of supplemental, adjunct, and adjuvant melatonin therapy for the prevention and treatment of prostate cancer.

Comparison of Erythrocyte and Reticulocyte Indices for Evaluation of Iron Deficiency by Two Automated Hematologic Analyzers.

The reticulocyte hemoglobin content and hypochromic erythrocyte percentage offer advantages in evaluation of iron deficiency, especially in inflammatory conditions. The aim of this study was to evaluate the correlation of reticulocyte hemoglobin content (CHr, Ret-He) and hypochromic erythrocyte percentage (%HYPO, Hypo-He) between two automated hematologic analyzers. The CHr and %HYPO values were determined using the Advia 2021i (Siemens), while the Ret-He and Hypo-He levels were assessed using the XN-3000 (Sysmex). Data from a total of 971 cases and 834 patients were collected. For reticulocyte hemoglobin content, there was a good linear correlation between CHr and Ret-He (r = 0.857, p < 0.001). For percentage of hypochromic erythrocytes, there was a better correlation between the two measures when using a second-degree polynomial equation (Hypo-He* = 0.4818 - 0.0218 x %HYPO + 0.0069 x %HYPO2) (r = 0.786, p < 0.001).

Induction and Maintenance Treatment of Lupus Nephritis: A Comprehensive Review of Meta-Analyses.

BACKGROUND: Lupus nephritis (LN) is present in over 50% of patients with systemic lupus erythematosus (SLE) which is managed with immunosuppressive and immunomodulatory therapies. However, several novel therapeutic approaches for LN are under investigation due to the adverse effects spectrum of conventional therapy; Methods: We performed a comprehensive review of meta-analyses aggregating the comparative efficacies of various pharmacotherapies for LN. We conducted a literature search and retrieved a total of 23 meta-analyses and network meta-analyses for summarization. Pharmacotherapies were evaluated across six major outcomes: remission, relapse, mortality, end stage kidney disease (ESKD) progression, infection, and malignancy. RESULT: Calcineurin inhibitors (CNI), particularly tacrolimus (TAC), in combination with glucocorticoids (GC) outperformed cyclophosphamide (CPA) with GC in the rate of remission, either complete or partial remission, and in terms of infectious complications. In maintenance therapy, MMF was superior to azathioprine (AZA) as the MMF-treated patients had lower relapse rate. INTERPRETATION: This review aggregates evidence of therapy for clinicians and sheds light on comparative efficacies of alternative LN treatments. As more promising agents are entering the market, such as voclosporin, belimumab, and obinutuzumab, LN management might undergo significant changes during the next years.

Neisseria gonorrhoeae Multivalent Maxibody with a Broad Spectrum of Strain Specificity and Sensitivity for Gonorrhea Diagnosis.

Gonorrhea is one of the most common, but still hidden and insidious, sexually transmitted diseases caused by Neisseria gonorrhoeae (gonococci). However, the diagnosis and treatment of gonorrhea are hampered by antigenic variability among gonococci, the lack of acquired immunity, and antimicrobial resistance. Further, strains resistant to cephalosporins, including ceftriaxone, the last line of defense, represent a growing threat, which prompted us to develop gonococci-specific diagnostic antibodies with broad-spectrum binding to gonococci strains to generate gonorrhea-detecting reagents. This study reports the identification of gonococci antibodies via bio-panning on gonococci cells using scFv-phage libraries. Reformatting the lead scFv-phage Clones 1 and 4 to a multivalent scFv1-Fc-scFv4 maxibody increased the sensitivity by up to 20-fold compared to the single scFv-Fc (maxibody) alone. Moreover, the multivalent maxibody showed broader cross-reactivity with clinical isolates and the ceftriaxone antibiotic-resistant World Health Organization (WHO) reference strain L. In contrast, the selected antibodies in the scFv-phage, maxibody, and multivalent maxibody did not bind to N. sicca, N. meningitides, and N. lactamica, suggesting the clinical and pharmaceutical diagnostic value of these selected antibodies for gonorrheal infections. The present study illustrates the advantages and potential application of multivalent maxibodies to develop rapid and sensitive diagnostic reagents for infectious diseases and cancer.

Association between erythema nodosum/ erythema induratum of Bazin and Mycobacterium tuberculosis infection in Koreans.

BACKGROUND: Erythema nodosum and erythema induratum of Bazin are similar inflammatory diseases of the lower extremities. These are clinically distinguishable entities, though overlap can occur. Both diseases are reported to be related to Mycobacterium tuberculosis infection, but it is very difficult to identify Mycobacterium tuberculosis in skin lesions. AIM: This study aimed to develop a new nested polymerase chain reaction targeting the IS6110 insertion sequence of M. tuberculosis to improve the M. tuberculosis detection rate in skin lesions of erythema nodosum or erythema induratum of Bazin. METHODS: From May 2016 to Jan 2018, 14 patients with clinically suspicious erythema nodosum or erythema induratum were enrolled in the study. Two cases were classified as erythema nodosum and 12 as erythema induratum. Individual patients were subjected to a 4-mm punch biopsy, and their venous whole blood was sampled immediately after diagnosis. RESULTS: Eight patients were tested for M. tuberculosis using QuantiFERON, of which seven (87.5%) were positive. IS6110-nested polymerase chain reaction on all 14 patients identified 11 (78.6%) positive cases. Four of the eight (50%) individuals tested with QuantiFERON were also positive in the IS6110 nested polymerase chain reaction. The difference between the outcomes of the QuantiFERON and the IS6110-nested polymerase chain reaction tests was not statistically significant. There was also no significant agreement between the results of both assays. Sequencing the IS6110-nested polymerase chain reaction products showed a 97%-100% nucleotide sequence identity with the H37Rv genome. CONCLUSION: It is important to test for tuberculosis in patients with multiple tender subcutaneous nodules on their lower extremities in high-burden tuberculosis countries like Korea. LIMITATIONS: We need to register more suspicious patients to verify the association between erythema nodosum/erythema induratum of Bazin and M. tuberculosis. Furthermore, it is necessary to improve the more sensitive polymerase chain reaction technique to identify M. tuberculosis directly in cutaneous lesions.

Foot-and-Mouth Disease Virus Evades Innate Immune Response by 3C-Targeting of MDA5.

Foot-and-mouth disease (FMD) is a highly contagious disease caused by FMD virus (FMDV) in cloven-hoofed animals. Retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5) are representative receptors in the cytoplasm for the detection of viral RNA and trigger antiviral responses, leading to the production of type I interferon. Although MDA5 is a crucial receptor for sensing picornavirus RNA, the interplay between MDA5 and FMDV is relatively unknown compared to the interplay between RIG-I and FMDV. Here, we observed that the FMDV infection inhibits MDA5 protein expression. Of the non-structural proteins, the Lb and 3C proteinases (Lbpro and 3Cpro) were identified to be primarily responsible for this inhibition. However, the inhibition by 3Cpro was independent of proteasome, lysosome and caspase-dependent pathway and was by 3C protease activity. A direct interaction between 3Cpro and MDA5 protein was observed. In conclusion, this is the first report that 3Cpro inhibits MDA5 protein expression as a mechanism to evade the innate immune response during FMDV infection. These results elucidate the pathogenesis of FMDV and provide fundamental insights for the development of a novel vaccine or therapeutic agent.

Treatment of severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19): a systematic review of in vitro, in vivo, and clinical trials.

Rationale: Coronavirus disease 2019 (COVID-19) has spread worldwide and poses a threat to humanity. However, no specific therapy has been established for this disease yet. We conducted a systematic review to highlight therapeutic agents that might be effective in treating COVID-19. Methods: We searched Medline, Medrxiv.org, and reference lists of relevant publications to identify articles of in vitro, in vivo, and clinical studies on treatments for severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and COVID-19 published in English until the last update on October 11, 2020. Results: We included 36 studies on SARS, 30 studies on MERS, and 10 meta-analyses on SARS and MERS in this study. Through 12,200 title and 830 full-text screenings for COVID-19, eight in vitro studies, 46 randomized controlled trials (RCTs) on 6,886 patients, and 29 meta-analyses were obtained and investigated. There was no therapeutic agent that consistently resulted in positive outcomes across SARS, MERS, and COVID-19. Remdesivir showed a therapeutic effect for COVID-19 in two RCTs involving the largest number of total participants (n = 1,461). Other therapies that showed an effect in at least two RCTs for COVID-19 were sofosbuvir/daclatasvir (n = 114), colchicine (n = 140), IFN-ß1b (n = 193), and convalescent plasma therapy (n = 126). Conclusions: This review provides information to help establish treatment and research directions for COVID-19 based on currently available evidence. Further RCTs are required.

Comparative Evaluation of Allplex Respiratory Panels 1, 2, 3, and BioFire FilmArray Respiratory Panel for the Detection of Respiratory Infections.

Multiplex nucleic acid amplification assays that simultaneously detect multiple respiratory pathogens in a single nasopharyngeal swab (NPS) specimen are widely used for rapid clinical diagnostics. We evaluated Allplex Respiratory Panel (RP) 1, 2, 3, and the BioFire FilmArray RP assay for detecting respiratory pathogens from NPS specimens. In all, 181 NPS specimens obtained from patients suspected of having respiratory infections during the non-influenza season (August-December 2019) were included. The Allplex RP 1, 2, and 3 detected 154 samples positive for respiratory viruses, whereas the BioFire FilmArray detected viruses in 98 samples. Co-infection with two or more viruses was detected in 41 and 17 NPS specimens by Allplex RP and the BioFire FilmArray RP, respectively. For adenoviruses, Allplex RP 1 detected 31 specimens, compared to 34 by the BioFire FilmArray. In all, 64 NPS specimens were positive for human enterovirus (HEV) and human rhinovirus (HRV) on the Allplex RP, in contrast to 39 HEV/HRV on the BioFire FilmArray. The parainfluenza virus (PIV-1-4) detection rate differed between the two systems. Most discrepant results were observed for NPS specimens with high cycle threshold values obtained by Allplex RP. This study showed concordant performance of the Allplex RP 1, 2, 3, and the BioFire FilmArray RP for the simultaneous detection of multiple respiratory viruses.

Increased Delta Neutrophil Index Is Associated With Poor Prognosis in Cadaver Donor Kidney Transplantation.

OBJECTIVE: Delta neutrophil index (DNI), representing an elevated fraction of circulating immature granulocyte in acute infection, has been reported as a useful, predictable marker for mortality in patients with sepsis. We have hypothesized that an increased recipient DNI is associated with poor prognosis in cadaver donor kidney transplantation. METHODS: We investigated patients undergoing kidney transplantation from cadaver donors from March 2013 to January 2018. Rejection was diagnosed by kidney biopsy with Banff classification and excluded subclinical rejection. RESULTS: In a total of 73 patients undergoing cadaver kidney transplantation, 25 (34.2%) patients were diagnosed with rejection based on the Banff classification. Among them, 11 patients were diagnosed with early rejection. The recipients' postoperative DNI (%) was different between patients with early rejection and patients without rejection (0.18 vs 1.21, P < .001). In the univariate logistic regression analysis, cold ischemic time, donor preoperative last creatinine level, postoperative DNI level, and perioperative infection were predictive of early rejection. However, in a multivariate adjusted logistic regression test, only a high level of DNI (odds ratio 12.307, 95% confidence interval [CI] 1.22-129.82) was associated with early rejection. The C-statistic was 0.777 (95% CI 0.604-0.951, P = .004) for DNI. In multivariate Cox regression analysis, the donor's last creatinine level (hazard ratio 2.25, 95% CI 1.26-4.13) and preoperative DNI (hazard ratio 14.02 95% CI 2.62-75.26) were predictors of renal survival. CONCLUSIONS: Increased DNI in cadaver donor kidney transplantation recipients might be one of the predictive values of early kidney rejection and prognosis.

Enhanced production of cadaverine by the addition of hexadecyltrimethylammonium bromide to whole cell system with regeneration of pyridoxal-5'-phosphate and ATP.

Cadaverine, also known as 1,5-pentanediamine, is an important platform chemical with a wide range of applications and can be produced either by fermentation or bioconversion. Bioconversion of cadaverine from l-lysine is the preferred method because of its many benefits, including rapid reaction time and an easy downstream process. In our previous study, we replaced pyridoxal-5-phosphate (PLP) with pyridoxal kinase (PdxY) along with pyridoxal (PL) because it could achieve 80% conversion with 0.4 M of l-lysine in 6 h. However, conversion was sharply decreased in the presence of high concentrations of l-lysine (i.e., 1 M), resulting in less than 40% conversion after several hours. In this study, we introduced an ATP regeneration system using polyphosphate kinase (ppk) into systems containing cadaverine decarboxylase (CadA) and PdxY for a sufficient supply of PLP, which resulted in enhanced cadaverine production. In addition, to improve transport efficiency, the use of surfactants was tested. We found that membrane permeabilization via hexadecyltrimethylammonium bromide (CTAB) increased the yield of cadaverine in the presence of high concentrations of l-lysine. By combining these two strategies, the ppk system and addition of CTAB, we enhanced cadaverine production up to 100% with 1 M of l-lysine over the course of 6 h.

Analytical and Clinical Performance Evaluation of the Abbott Architect PIVKA Assay.

Protein induced by vitamin K absence (PIVKA) is measured using various assays and is used to help diagnose hepatocellular carcinoma. The present study evaluated the analytical and clinical performances of the recently released Abbott Architect PIVKA assay. Precision, linearity, and correlation tests were performed in accordance with the Clinical Laboratory Standardization Institute guidelines. Sample type suitability was assessed using serum and plasma samples from the same patients, and the reference interval was established using sera from 204 healthy individuals. The assay had coefficients of variation of 3.2-3.5% and intra-laboratory variation of 3.6-5.5%. Linearity was confirmed across the entire measurable range. The Architect PIVKA assay was comparable to the Lumipulse PIVKA assay, and the plasma and serum samples provided similar results. The lower reference limit was 13.0 mAU/mL and the upper reference limit was 37.4 mAU/mL. The ability of the Architect PIVKA assay to detect hepatocellular carcinoma was comparable to that of the alpha-fetoprotein test and the Lumipulse PIVKA assay. The Architect PIVKA assay provides excellent analytical and clinical performance, is simple for clinical laboratories to adopt, and has improved sample type suitability that could broaden the assay's utility.

Evaluation of a New Multiplex Real-Time PCR Assay for Detecting Gastroenteritis-Causing Viruses in Stool Samples.

BACKGROUND: Diarrhea has been the second leading cause of death among children under the age of five, and the rapid and accurate pathogen diagnosis in patients with diarrhea is crucial for reducing morbidity and mortality. A newly developed one-step multiplex real-time PCR assay, the Allplex GI-Virus Assay, was evaluated for its ability to detect six diarrhea-causing viruses (rotavirus, norovirus genogroup I (GI) and genogroup II (GII), enteric adenovirus, astrovirus, and sapovirus) in stool samples. METHODS: The performance of the Allplex assay was compared with those of another multiplex PCR assay (Seeplex Diarrhea-V Ace Detection) and genotyping by sequencing, using 446 stool samples from patients with acute gastroenteritis. RESULTS: The overall agreement rates between the results of the Allplex and Seeplex assays were 98.7% for rotavirus, 99.1% for norovirus GI, 93.3% for norovirus GII, 98.0% for adenovirus, and 99.6% for astrovirus. The overall agreement rates between the Allplex assay and genotyping were 99.1% for rotavirus, 99.1% for norovirus GI, 98.7% for norovirus GII, 89.7% for adenovirus, 98.2% for astrovirus, and 99.8% for sapovirus. In addition, eight rotavirus genotypes, three norovirus GI genotypes, four norovirus GII genotypes, eight adenovirus genotypes, two astrovirus genotypes, and two sapovirus genotypes were detected. CONCLUSIONS: The Allplex assay showed high agreement with Seeplex and genotyping results, and was able to additionally detect sapoviruses. The Allplex assay could be useful in identifying viral gastrointestinal infections in patients with acute gastroenteritis symptoms.

Determination of optimal age for single vaccination of growing pigs with foot-and-mouth disease bivalent vaccine in South Korea.

In South Korea, pigs were vaccinated once between 8 and 12 weeks of age because of the injection-site granulomas. Therefore this study was performed to determine the optimal age for single vaccination of growing pigs with the currently used type O FMD vaccine. With 498 pigs divided into four groups, seroprevalence of the antibody was analyzed with enzyme-linked immunosorbent assay. Although double vaccination is necessary to completely protect growing pigs from FMD virus infection with the current vaccine, the age of 8 weeks can be considered as the optimal age for piglet vaccination if the booster injection is unavailable.

Comparison of the Luminex xTAG Respiratory Viral Panel Fast v2 Assay With Anyplex II RV16 Detection Kit and AdvanSure RV Real-Time RT-PCR Assay for the Detection of Respiratory Viruses.

BACKGROUND: The accurate and rapid identification of the causative viruses is important for the timely diagnosis and management of respiratory infections. Multiplex molecular diagnostic techniques have been widely adopted to detect respiratory viruses. We compared the results of a newly upgraded, multiplex, molecular bead-based respiratory viral panel (RVP) assay with the results of Anyplex II RV16 detection kit and AdvanSure RV real-time RT-PCR assay. METHODS: We tested 254 respiratory specimens and cultured viral strains using the Luminex xTAG RVP Fast v2 assay (Luminex Molecular Diagnostics, Canada) and Anyplex II RV16 detection kit and compared the results. Specimens showing discordant results between the two assays were tested with a AdvanSure RV real-time RT-PCR assay. RESULTS: Of the 254 respiratory specimens, there was total agreement in the results between the xTAG RVP Fast v2 assay and the other real-time PCR assay in 94.1-100% of the specimens. The agreement levels were relatively low (94.1-97.6%) for specimens of adenovirus, coronavirus NL63, and parainfluenza type 3. In comparison to the other assay, the xTAG RVP Fast v2 assay detected a higher number of parainfluenza type 3 (4 cases) and metapneumovirus (9 cases). CONCLUSIONS: The xTAG RVP Fast v2 assay showed comparable capabilities compared with the other assays; it will be useful for identifying respiratory viral infections in patients with respiratory symptoms. Clinicians should be aware of the characteristics of the assays they use, since different assays show different detectability for each virus.

Analysis of Respiratory Viral Infections Detected Using Multiplex Real-Time PCR in Hwaseong, Korea from 2013 to 2015.

BACKGROUND: We investigated the incidences and age-related/seasonal variations of respiratory virus infections in a regional area in Korea. METHODS: A total of 3,467 respiratory specimens from patients with acute respiratory infection symptoms in a teaching hospital were tested for respiratory viruses during 2013 - 2015. RESULTS: At least one virus was detected in 2,561 of the 3,467 specimens (73.9%), and 706 patients (20.4%) were positive for two or more viruses. The most frequently detected viruses were rhinovirus (23.9%), respiratory syncytial virus B (15.5%), and adenovirus (12.5%). Most of the patients (with and without a detected virus) were children. Young children (< 5 years old) were significantly more likely to have two or more viruses compared to older individuals (p < 0.0001). Most viruses exhibited seasonal variations. CONCLUSIONS: This study revealed the incidence of respiratory virus infections. These findings can enhance our understanding of the distribution of respiratory viruses according to patient age and season.