Factors associated with real-time RT-PCR cycle threshold values among medically attended influenza episodes.

We evaluated the cycle threshold (CT) values of 1,160 influenza A positive and 806 influenza B positive specimens from two seasons of the US Flu VE Network to identify factors associated with CT values. Low CT values (high genomic load) were associated with shorter intervals between illness onset and specimen collection, young age (ages 3-8 years old), and self-rated illness severity for both influenza A and B. Low CT values were also associated with reported fever/feverishness and age ≥65 years for influenza A.

Bordetella pertussis is an uncommon pathogen in children hospitalized with bronchiolitis during the winter season.

Background: In the United States (U.S.), Bordetella pertussis incidence has increased.

Respiratory syncytial virus genomic load and disease severity among children hospitalized with bronchiolitis: multicenter cohort studies in the United States and Finland.

Background: We investigated whether children with a higher respiratory syncytial virus (RSV) genomic load are at a higher risk of more-severe bronchiolitis.

Methods: Two multicenter prospective cohort studies in the United States and Finland used the same protocol to enroll children aged <2 years hospitalized for bronchiolitis and collect nasopharyngeal aspirates. By using real-time polymerase chain reaction analysis, patients were classified into 3 genomic load status groups: low, intermediate, and high.

Lactate dehydrogenase and caspase activity in nasopharyngeal secretions are predictors of bronchiolitis severity.

Background: Bronchiolitis is the leading cause of hospitalization in infants. Biomarkers of disease severity might help in clinical management.

Objective: To determine the clinical predictiveness of NW-LDH, NW-caspase 3/7, and NW-LDH/NW-caspase 3/7 ratio in bronchiolitis.

Gene sequence variability of the three surface proteins of human respiratory syncytial virus (HRSV) in Texas.

Human respiratory syncytial virus (HRSV) has three surface glycoproteins: small hydrophobic (SH), attachment (G) and fusion (F), encoded by three consecutive genes (SH-G-F). A 270-nt fragment of the G gene is used to genotype HRSV isolates. This study genotyped and investigated the variability of the gene and amino acid sequences of the three surface proteins of HRSV strains collected from 1987 to 2005 from one center.

Detection of NH1N1 influenza virus in nonrespiratory sites among children.

Among 20 children admitted with laboratory-confirmed influenza, viral RNA was detected in respiratory secretion, stool and blood in 19, 5 and 1 children, respectively. Gastrointestinal symptoms were common but were not associated with viral RNA in stool. nH1N1 viremia was detected, for the first time, in an immunocompetent child.

LDH concentration in nasal-wash fluid as a biochemical predictor of bronchiolitis severity.

Objective: Because the decision to hospitalize an infant with bronchiolitis is often supported by subjective criteria and objective indicators of bronchiolitis severity are lacking, we tested the hypothesis that lactate dehydrogenase (LDH), which is released from injured cells, is a useful biochemical indicator of bronchiolitis severity.

Patients And Methods: We retrospectively analyzed a study of children <24 months old presenting to the emergency department with bronchiolitis. Demographic, clinical information, nasal wash (NW), and serum specimens were obtained.

T lymphocytes contribute to antiviral immunity and pathogenesis in experimental human metapneumovirus infection.

Human metapneumovirus (hMPV), a member of the family Paramyxoviridae, is a leading cause of lower respiratory tract infections in children, the elderly, and immunocompromised patients. Virus- and host-specific mechanisms of pathogenesis and immune protection are not fully understood. By an intranasal inoculation model, we show that hMPV-infected BALB/c mice developed clinical disease, including airway obstruction and hyperresponsiveness (AHR), along with histopathologic evidence of lung inflammation and viral replication.

The search for adenovirus 14 in children in Houston, Texas.

Adenovirus (Ad)14 has recently emerged in the United States causing outbreaks of severe respiratory disease. To determine if Ad14 circulated in Houston, Texas, during the same time as an outbreak in military recruits in nearby San Antonio, 215 pediatric adenovirus isolates were serotyped using microneutralization. None were Ad14; Ad1, Ad2, and Ad3 were the most common identified serotypes.

Human metapneumovirus and respiratory syncytial virus infections in older children with cystic fibrosis.

Background: Human metapneumovirus (hMPV) has been isolated from children with acute respiratory infection worldwide. Its epidemiology remains to be defined in children with cystic fibrosis (CF). We describe the epidemiology and clinical impact of hMPV in CF children and compared it to respiratory syncytial virus (RSV).

Development of a cotton rat-human metapneumovirus (hMPV) model for identifying and evaluating potential hMPV antivirals and vaccines.

Hispid cotton rats were inoculated with two different human metapneumovirus (hMPV) subtype A strains and one subtype B hMPV. Although no overt disease was seen in any virus-inoculated animal, following an eclipse phase, significant pulmonary virus titers were observed in every hMPV-inoculated animal through day 7 post virus inoculation (p.i.

Conserved CTL epitopes on the adenovirus hexon protein expand subgroup cross-reactive and subgroup-specific CD8+ T cells.

Adenoviruses often cause lethal infections in immunocompromised individuals. Adoptive transfer of immune T cells offers a therapeutic option, but this strategy has been hindered by the paucity of information on molecular targets of cellular immunity and by the immunologic heterogeneity of the 51 human adenoviruses, which are grouped from A to F on the basis of genome size, composition, homology, and organization. Clonal analysis of the adenovirus-specific cytotoxic T lymphocyte (CTL) responses of seropositive individuals identified 5 novel CD8(+) T-cell epitopes, all located in conserved regions of the capsid protein hexon.

Comparison of the inhibition of human metapneumovirus and respiratory syncytial virus by NMSO3 in tissue culture assays.

Human metapneumovirus (hMPV) is a recently elucidated respiratory virus pathogen for which there are no agents currently licensed to prevent or treat infections caused by it. However, NMSO3 has been reported to inhibit replication of human respiratory syncytial virus (hRSV), a virus that is closely related to hMPV, both in vitro in tissue culture cells and in vivo in cotton rats. For this reason, experiments were performed to compare the antiviral activity of NMSO3 against both hRSV and hMPV in tissue culture-based assays.

Fiber-modified adenoviruses generate subgroup cross-reactive, adenovirus-specific cytotoxic T lymphocytes for therapeutic applications.

Adenovirus (Ad) infections are responsible for considerable morbidity and mortality, particularly in pediatric hematopoietic stem cell transplant (HSCT) recipients. To date there is no therapy. The present study was motivated by the potential for using adoptive immunotherapy as either prophylaxis or treatment for Ad infections and associated diseases.

Comparison of the inhibition of human metapneumovirus and respiratory syncytial virus by ribavirin and immune serum globulin in vitro.

Human metapneumovirus (hMPV) is a newly recognized pathogen that like its better-known relative, human respiratory syncytial virus (hRSV), appears to be ubiquitous and an important cause of respiratory disease in diverse subpopulations. No antivirals or vaccines are currently approved for the treatment or prevention of hMPV infections. However, ribavirin is licensed to treat serious hRSV-induced infections in children and immune globulin designed for intravenous administration (i.

Correlates of immunity to respiratory syncytial virus (RSV) associated-hospitalization: establishment of minimum protective threshold levels of serum neutralizing antibodies.

Objective: To determine if respiratory syncytial virus (RSV) specific, serum antibody titers correlate with protection against RSV associated-hospitalization at all ages.

Design: Participants who were enrolled in a trial to determine the frequency of specific virus infections associated with hospitalization [J. Am.

Immunogenicity of a new purified fusion protein vaccine to respiratory syncytial virus: a multi-center trial in children with cystic fibrosis.

A third generation, purified fusion protein (PFP-3) vaccine was developed to prevent severe respiratory syncytial virus (RSV) disease in high-risk groups. A phase II, multi-center, adjuvant-controlled trial was performed in RSV seropositive children with cystic fibrosis (CF); 151 received the adjuvant-control and 143 received the vaccine. Details of the vaccine-induced immune response are presented.