Project description:OBJECTIVE:This study was performed to further identify the previously uncharacterized human coronavirus 229E (hCoV-229E) and human coronavirus OC43 (hCoV-OC43) in Thailand by using the RT-PCR technique. In addition, we performed this study in order to delineate the prevalence, the potential clinical impacts and evaluation of the genetic characterization of this pathogen in young children who presented with acute lower respiratory tract infections (ALRI). METHODS:We obtained nasopharyngeal secretions (NPs) from 226 children <5 years of age who were either attending the outpatient department or hospitalized with ALRI from March 2002 to July 2003. All clinical, laboratory, RT-PCR, direct sequencing and phylogenetic analysis data were collected and analyzed. RESULTS:Of the 226 NPs samples from infants and young children presented with ALRI, 8 (3.54%) were positive for hCoV-229E, 2 (0.88%) were positive for hCoV-OC43, and 1 (0.44%) had co-infection. The following clinical presentations were noted: fever (100%), rhinitis (44%), acute bronchiolitis (44%), viral pneumonia (33%), viral pneumonia triggering asthma exacerbation (11%) as well as viral pneumonia causing BPD exacerbation (11%). All positive samples were subjected to direct sequencing. The amino acid sequences had 82-99% similarity to previous sequences stored in the GenBank database. CONCLUSION:The molecular technique we applied to detect human coronavirus appears justified as a valuable diagnostic approach to elucidate the prevalence, cause and clinical implications of ALRI among infants and young children.
Project description:Analysis of transcriptional profiles in whole blood from children < 2 years of age (and healthy matched controls) with RSV, rhinovirus and influenza infection. The hypothesis tested is that transcriptional profile heterogeneity will reflect patient clinical heterogeneity and that RSV infection induces a distinct host response compared with influenza and rhinovirus infection Total RNA extracted from whole blood (lysed in Tempus tubes) drawn from individual pediatric patients with acute RSV, influenza and Rhinovirus lower respiratory tract infection. A total of 241 samples are analyzed: 135 with acute RSV LRTI, 30 with Rhinovirus LRTI, 16 with influenza LRTI, 39 age-sex matched healthy controls and 21 samples obtained one month after the acute hospitalization in children with RSV. Samples GSM1226237-GSM1226272, which were hybridized to Platform GPL10558, were normalized separately from the other Samples in this Series, which were hybridized to Platform GPL6884. 'GSE38900_non-normalized_GSM1226237-GSM1226272.txt.gz' includes the non-normalized data for Samples GSM1226237-GSM1226272; 'GSE38900_non-normalized.txt.gz' includes the non-normalized data for the other Samples.
Project description:BackgroundMolecular diagnostics enable sensitive detection of respiratory viruses, but their clinical significance remains unclear in pediatric lower respiratory tract infection (LRTI). We aimed to determine whether viral coinfections increased life-threatening disease in a large cohort.MethodsMolecular testing was performed for respiratory viruses in nasopharyngeal aspirates collected from children aged <5 years within 24 hours of hospital admission during sentinel surveillance for severe acute respiratory illness (SARI) hospitalization conducted in South Africa during February 2009-December 2013. The primary outcome was life-threatening disease, defined as mechanical ventilation, intensive care unit admission, or death.ResultsOf 2322 HIV-uninfected children with respiratory syncytial virus (RSV)-associated LRTI, 1330 (57.3%) had RSV monoinfection, 38 (1.6%) had life-threatening disease, 575 (24.8%) had rhinovirus, 347 (14.9%) had adenovirus (ADV), and 30 (1.3%) had influenza virus. RSV and any other viral coinfection was not associated with severe disease, ADV coinfection had increased odds of life-threatening disease (adjusted OR, 3.4; 95% CI, 1.6-7.2; P = .001), and influenza coinfection had increased odds of life-threatening disease and prolonged length of stay (adjusted OR, 2.1; 95% CI, 1.0-4.5; P = .05) compared with RSV monoinfection.ConclusionsRSV coinfection with any respiratory virus is not associated with more severe disease when compared to RSV alone in this study. However, increased life-threatening disease in RSV-ADV and RSV-influenza coinfection warrants further study.
Project description:BackgroundVarious case definitions of respiratory syncytial virus lower respiratory tract infection (RSV-LRTI) are currently proposed. We assessed the performance of three clinical case definitions against the World Health Organization definition recommended in 2015 (WHO 2015).MethodsIn this prospective cohort study conducted in eight countries, 2401 children were followed up during 2 years from birth. Suspected LRTIs were detected via active and passive surveillance, followed by in-person clinical evaluation including single timepoint respiratory rate and oxygen saturation (by pulse oximetry) assessment, and nasopharyngeal sampling for RSV testing by polymerase chain reaction. Agreement between case definitions was evaluated using Cohen's κ statistics.ResultsOf 1652 suspected LRTIs, 227 met the WHO 2015 criteria for RSV-LRTI; 73 were classified as severe. All alternative definitions were highly concordant with the WHO 2015 definition for RSV-LRTI (κ: 0.95-1.00), but less concordant for severe RSV-LRTI (κ: 0.47-0.82). Tachypnea was present for 196/226 (86.7%) WHO 2015 RSV-LRTIs and 168/243 (69.1%) LRTI/bronchiolitis/pneumonia cases, clinically diagnosed by non-study physicians. Low oxygen saturation levels were observed in only 55/226 (24.3%) WHO 2015 RSV-LRTIs.ConclusionThree case definitions for RSV-LRTI showed high concordance with the WHO 2015 definition, while agreement was lower for severe RSV-LRTI. In contrast to increased respiratory rate, low oxygen saturation was not a consistent finding in RSV-LRTIs and severe RSV-LRTIs. This study demonstrates that current definitions are highly concordant for RSV-LRTIs, but a standard definition is still needed for severe RSV-LRTI.
Project description:BACKGROUND. Lower respiratory tract infection (LRTI) is a leading cause of death in children worldwide. LRTI diagnosis is challenging since non-infectious respiratory illnesses appear clinically similar and existing microbiologic tests are often falsely negative or detect incidentally-carried microbes common in children. These challenges result in antimicrobial overuse and adverse patient outcomes. Lower airway metagenomics has the potential to detect host and microbial signatures of LRTI. Whether it can be applied at scale and in a pediatric population to enable improved diagnosis and precision treatment remains unclear. METHODS. We used tracheal aspirate RNA-sequencing to profile host gene expression and respiratory microbiota in 261 children with acute respiratory failure. We developed a random forest gene expression classifier for LRTI by training on patients with an established diagnosis of LRTI (n=117) or of non-infectious respiratory failure (n=50). We then developed a classifier that integrates the: i) host LRTI probability, ii) abundance of respiratory viruses, and iii) dominance in the lung microbiome of bacteria/fungi considered pathogenic by a rules-based algorithm. RESULTS. The host classifier achieved a median AUC of 0.967 by 5-fold cross-validation, driven by activation markers of T cells, alveolar macrophages and the interferon response. The integrated classifier achieved a median AUC of 0.986 and significantly increased the confidence of patient classifications. When applied to patients with an uncertain diagnosis (n=94), the integrated classifier indicated LRTI in 52% of cases and nominated likely causal pathogens in 98% of those. CONCLUSIONS. Lower airway metagenomics enables accurate LRTI diagnosis and pathogen identification in a heterogeneous cohort of critically ill children through integration of host, pathogen, and microbiome features.
Project description:Severe lower respiratory tract infection (LRTI) in infants caused by respiratory syncytial virus (RSV) has been associated with later pneumonia hospitalization among children. To determine risk for pneumonia after RSV hospitalization in infancy, we conducted a retrospective cohort analysis of 2,813 infants admitted to a hospital in Kenya and identified readmissions for pneumonia among this group during early childhood (<60 months of age). Incidence of readmission for pneumonia was higher for children whose first admission as infants was for LRTI and who were <3 months of age than for children who were first admitted as infants for non-LRTI, irrespective of RSV status. Incidence of readmission for pneumonia with wheeze was higher for children whose first admission involved RSV compared with those who had non-RSV LRTI. Excess pneumonia risk persisted for 2 years after the initial hospitalization. Close postdischarge follow-up of infants with LRTI, with or without RSV, could help prevent severe pneumonia later in childhood.
Project description:Analysis of transcriptional profiles in whole blood from children < 2 years of age (and healthy matched controls) with RSV, rhinovirus and influenza infection. The hypothesis tested is that transcriptional profile heterogeneity will reflect patient clinical heterogeneity and that RSV infection induces a distinct host response compared with influenza and rhinovirus infection