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Respiratory Virus (respiratory + virus)
Selected AbstractsRhinovirus increases human ,-defensin-2 and -3 mRNA expression in cultured bronchial epithelial cellsFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2003Louise A Duits Abstract Human ,-defensins (hBDs) are antimicrobial peptides that play important roles in host defense against infection, inflammation and immunity. Previous studies showed that micro-organisms and proinflammatory mediators regulate the expression of these peptides in airway epithelial cells. The aim of the present study was to investigate the modulation of expression of hBDs in cultured primary bronchial epithelial cells (PBEC) by rhinovirus-16 (RV16), a respiratory virus responsible for the common cold and associated with asthma exacerbations. RV16 was found to induce expression of hBD-2 and -3 mRNA in PBEC, but did not affect hBD-1 mRNA. Viral replication appeared essential for rhinovirus-induced ,-defensin mRNA expression, since UV-inactivated rhinovirus did not increase expression of hBD-2 and hBD-3 mRNA. Exposure to synthetic double-stranded RNA (dsRNA) molecule polyinosinic:polycytidylic acid had a similar effect as RV16 on mRNA expression of these peptides in PBEC. In line with this, PBEC were found to express TLR3, a Toll-like receptor involved in recognition of dsRNA. This study shows that rhinovirus infection of PBEC leads to increased hBD-2 and hBD-3 mRNA expression, which may play a role in both the uncomplicated common cold and in virus-associated exacerbations of asthma. [source] An early report from newly established laboratory-based influenza surveillance in Lao PDRINFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 2 2010Phengta Vongphrachanh Please cite this paper as: Vongphrachanh P, Simmerman JM, Phonekeo D, Pansayavong V, Sisouk T, Ongkhamme S, Bryce GT, Corwin A, Bryant JE. An early report from newly established laboratory-based influenza surveillance in Lao PDR. Influenza and Other Respiratory Viruses 4(2), 47,52. Background, Prior to 2007, little information was available about the burden of influenza in Laos. We report data from the first laboratory-based influenza surveillance system established in the Lao People's Democratic Republic. Methods, Three hospitals in the capital city of Vientiane began surveillance for influenza-like illness (ILI) in outpatients in 2007 and expanded to include hospitalized pneumonia patients in 2008. Nasal/throat swab specimens were collected and tested for influenza and other respiratory viruses by multiplex ID-TagTM respiratory viral panel (RVP) assay on a Luminex® 100× MAP IS instrument (Qiagen, Singapore). Results, During January 2007 to December 2008, 287 of 526 (54·6%) outpatients with ILI were positive for at least one respiratory virus. Influenza was most commonly identified, with 63 (12·0%) influenza A and 92 (17·5%) influenza B positive patients identified. In 2008, six of 79 (7·6%) hospitalized pneumonia patients were positive for influenza A and four (5·1%) were positive for influenza B. Children <5 years represented 19% of viral infections in outpatients and 38% of pneumonia inpatients. Conclusion, Our results provide the first documentation of influenza burden among patients with febrile respiratory illness and pneumonia requiring hospitalization in Laos. Implementing laboratory-based influenza surveillance requires substantial investments in infrastructure and training. However, continuing outbreaks of avian influenza A/H5N1 in poultry and emergence of the 2009 influenza A(H1N1) pandemic strain further underscore the importance of establishing and maintaining influenza surveillance in developing countries. [source] Impact of human coronavirus infections in otherwise healthy children who attended an emergency department,JOURNAL OF MEDICAL VIROLOGY, Issue 12 2006Susanna Esposito Abstract This prospective clinical and virological study of 2,060 otherwise healthy children aged <15 years of age (1,112 males; mean age,±,SD, 3.46,±,3.30 years) who attended the Emergency Department of Milan University's Institute of Pediatrics because of an acute disease excluding trauma during the winter season 2003,2004 was designed to compare the prevalence and clinical importance of human coronaviruses (HCoVs) in children. Real-time polymerase chain reaction (PCR) in nasopharyngeal aspirates revealed HCoV infection in 79 cases (3.8%): 33 HCoV-229E (1.6%), 13 HCoV-NL63 (0.6%), 11 HCoV-OC43 (0.5%), none HCoV-HKU1 genotype A, and 22 (1.1%) co-detections of a HCoV and another respiratory virus. The HCoVs were identified mainly in children with upper respiratory tract infection; there was no significant difference in clinical presentation between single HCoV infections and HCoV co-infections. Diagnostic methods were used in a limited number of patients, and the therapy prescribed and clinical outcomes were similar regardless of the viral strain. There were a few cases of other members of the households of HCoV-positive children falling ill during the 5,7 days following enrollment. These findings suggest that HCoV-229E and HCoV-OC43 have a limited clinical and socioeconomic impact on otherwise healthy children and their household contacts, and the HCoV-NL63 identified recently does not seem to be any different. The quantitative and qualitative role of HCoV-HKU1 genotype A is apparently very marginal. J. Med. Virol. 78:1609,1615, 2006. © 2006 Wiley-Liss, Inc. [source] Impact of human metapneumovirus and human cytomegalovirus versus other respiratory viruses on the lower respiratory tract infections of lung transplant recipientsJOURNAL OF MEDICAL VIROLOGY, Issue 3 2006Giuseppe Gerna Abstract Viral respiratory tract infections in lung transplant recipients may be severe. During three consecutive winter-spring seasons, 49 symptomatic lung transplant recipients with suspected respiratory viral infection, and 26 asymptomatic patients were investigated for presence of respiratory viruses either in 56 nasopharyngeal aspirate or 72 bronchoalveolar lavage samples taken at different times after transplantation. On the whole, 1 asymptomatic (3.4%) and 28 symptomatic (57.1%) patients were positive for human metapneumovirus (hMPV, 4 patients), influenza virus A (3 patients), and B (2 patients), respiratory syncytial virus (2 patients), human coronavirus (2 patients), human parainfluenza virus (2 patients), rhinovirus (5 patients), while 4 patients were coinfected by 2 respiratory viruses, and 5 were infected sequentially by 2 or more respiratory viruses. In bronchoalveolar lavage samples, hMPV predominated by far over the other viruses, being responsible for 60% of positive specimens, whereas other viruses were present in nasopharyngeal aspirates at a comparable rate. RT-PCR (detecting 43 positive samples/128 examined) was largely superior to monoclonal antibodies (detecting 17 positive samples only). In addition, HCMV was detected in association with a respiratory virus in 4/18 HCMV-positive patients, and was found at a high concentration (>105 DNA copies/ml) in 3/16 (18.7%) patients with HCMV-positive bronchoalveolar lavage samples and pneumonia. Coinfections and sequential infections by HCMV and respiratory viruses were significantly more frequent in patients with acute rejection and steroid treatment. In conclusion: (i) about 50% of respiratory tract infections of lung transplant recipients were associated with one or more respiratory viruses; (ii) hMPV largely predominates in bronchoalveolar lavage of symptomatic lung transplant recipients, thus suggesting a causative role in lower respiratory tract infections; (iii) RT-PCR appears to be the method of choice for detection of respiratory viruses in lung transplant recipients, (iv) a high HCMV load in bronchoalveolar lavage is a risk factor for viral pneumonia, suggesting some measure of intervention for the control of viral infection. J. Med. Virol. 78:408,416, 2006. © 2006 Wiley-Liss, Inc. [source] Considering human,primate transmission of measles virus through the prism of risk analysisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2006Lisa Jones-Engel Abstract Measles is a respiratory virus that is endemic to humans. Human,nonhuman primate (NHP) transmission of the measles virus has been shown to cause significant morbidity and mortality in NHP populations. We investigated serological evidence of exposure to measles virus in two free-ranging populations of macaques at the Bukit Timah (BTNR) and Central Catchment Nature (CCNR) reserves in Singapore and the Swoyambhu Temple in Katmandu, Nepal. At BTNR/CCNR none of the 38 macaques (Macaca fascicularis) sampled were seropositive for antibodies to measles virus. In contrast, at Swoyambhu 100% (n=39) of the macaques (M. mulatta) sampled were seropositive for antibodies to the measles virus. Here the contrasting seroprevalences of the two sites are analyzed using risk analysis. These case studies show how risk analysis can be used to approach the phenomenon of cross-species pathogen transmission. Am. J. Primatol. 68:868,879, 2006. © 2006 Wiley-Liss, Inc. [source] Comparison of cytokine responses in nasopharyngeal aspirates from children with viral lower respiratory tract infectionsACTA PAEDIATRICA, Issue 4 2009Jung Hye Byeon Abstract Aim: To determine whether nasopharyngeal aspirates (NPAs) cytokine response is different according to the causative viruses in children with lower respiratory tract infections (LRTI). Methods: NPAs from 277 children with LRTI caused by respiratory virus were evaluated. Based on the proven viral agents, LRTI patients were divided into four groups. Levels of IL-4, IL-5 and IFN-, were determined by ELISA. Results: Patients with influenza virus infection demonstrated significantly lower IL-4 and IL-5 levels than those with other three groups. Patients with respiratory syncytial virus (RSV) infection showed an increase in production of IL-4 and IL-5, and a decrease in the IFN-, level when compared to patients with influenza virus infection. Interestingly, a similar Th2 response was seen in patients with parainfluenza virus or adenovirus infection. Conclusion: These results demonstrate that respiratory viruses can induce different local cytokine responses. However, Th2 biased responses are not unique for RSV but seem to be predominant in respiratory viruses of young children. [source] | |||||||||||||