Viral infectivity in paediatric SARS-CoV-2 clinical samples does not vary by age.

At the start of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, there was much uncertainty about the role of children in infection and transmission dynamics. Through the course of the pandemic, it became clear that children were susceptible to SARS-CoV-2 infection, although they were experiencing a notable lack of severe disease outcomes as compared to the adult population. This trend held true with the emergence of new SARS-CoV-2 variants, even in paediatric populations that were ineligible to be vaccinated.

Viral infectivity in pediatric SARS-CoV-2 clinical samples does not vary by age.

During the early months of the SARS-CoV-2 pandemic, notable uncertainty emerged regarding the role of children in transmission dynamics. With time, it became more clear that children were susceptible to infection with SARS-CoV-2, but that the vast majority of children experienced mild symptoms with lower incidence of severe disease. This pattern remained consistent despite the later emergence of SARS-CoV-2 variants, including Delta and Omicron, even among children <5 ineligible for vaccination.

Inhibition of Human Coronaviruses by Antimalarial Peroxides.

As the toll of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic continues, efforts are ongoing to identify new agents and repurpose safe drugs for its treatment. Antimalarial peroxides have reported antiviral and anticancer activities. Here, we evaluated the activities of artesunate (AS) and two ozonides (OZ418 and OZ277) against human α-coronavirus NL63 and β-coronaviruses OC43 and SARS-CoV-2 in several cell lines.

COVID-19 pre-procedural testing strategy and early outcomes at a large tertiary care children's hospital.

Purpose: With the emergence of the coronavirus disease-2019 (COVID-19) pandemic, institutions were tasked with developing individualized pre-procedural testing strategies that allowed for re-initiation of elective procedures within national and state guidelines. This report describes the experience of a single US children's hospital (Children's Wisconsin, CW) in developing a universal pre-procedural COVID-19 testing protocol and reports early outcomes.

Methods: The CW pre-procedural COVID-19 response began with the creation of a multi-disciplinary taskforce that sought to develop a strategy for universal pre-procedural COVID-19 testing which (1) maximized patient safety, (2) prevented in-hospital viral transmission, (3) conserved resources, and (4) allowed for resumption of procedural care within institutional capacity.

Sequencing and analysis of globally obtained human parainfluenza viruses 1 and 3 genomes.

Human Parainfluenza viruses (HPIV) type 1 and 3 are important causes of respiratory tract infections in young children globally. HPIV infections do not confer complete protective immunity so reinfections occur throughout life. Since no effective vaccine is available for the two virus subtypes, comprehensive understanding of HPIV-1 and HPIV-3 genetic and epidemic features is important for diagnosis, prevention, and treatment of HPIV-1 and HPIV-3 infections.

Establishment of a lethal aged mouse model of human respiratory syncytial virus infection.

Human respiratory syncytial virus (HRSV) infection is a significant cause of morbidity and mortality, particularly among the children and the elderly. Despite extensive efforts, there is currently no formally approved vaccine and effective antiviral options against HRSV infection are limited. The development of vaccines and antiviral strategies for HRSV was partly hampered by the lack of an efficient lethal mouse model to evaluate the efficacy of the candidate vaccines or antivirals.

Simulated Respiratory Secretion for Use in the Development of Influenza Diagnostic Assays.

Many assays have been developed for the detection of influenza virus which is an important respiratory pathogen. Development of these assays commonly involves the use of human clinical samples for validation of their performance. However, clinical samples can be difficult to obtain, deteriorate over time, and be inconsistent in composition.

Sequencing and analysis of globally obtained human respiratory syncytial virus A and B genomes.

Background: Human respiratory syncytial virus (RSV) is the leading cause of respiratory tract infections in children globally, with nearly all children experiencing at least one infection by the age of two. Partial sequencing of the attachment glycoprotein gene is conducted routinely for genotyping, but relatively few whole genome sequences are available for RSV. The goal of our study was to sequence the genomes of RSV strains collected from multiple countries to further understand the global diversity of RSV at a whole-genome level.

Complete genome sequences of one human respiratory syncytial antigenic group a virus from china and its four mouse-adapted isolates.

In this study, one human respiratory syncytial antigenic group A virus (HRSV-A-GZ08-0) and its four BALB/c mouse-adapted isolates were sequenced and elucidated. Nineteen nucleotides were mutated between HRSV-A-GZ08-0 and the four mouse-adapted isolates.

Analytical reactivity of 13 commercially available rapid influenza diagnostic tests with H3N2v and recently circulating influenza viruses.

Objectives: Rapid influenza diagnostic tests (RIDTs) used widely in clinical practice are simple to use and provide results within 15 minutes; however, reported performance is variable, which causes concern when novel or variant viruses emerge. This study's goal was to assess the analytical reactivity of 13 RIDTs with recently circulating seasonal and H3N2v influenza viruses, using three different viral measures.

Design: Virus stocks were characterized by infectious dose (ID50 ) and nucleoprotein (NP) concentration, diluted at half-log dilutions, and tested with each RIDT and real-time RT-PCR.

Prevalence of respiratory syncytial virus-associated lower respiratory infection and apnea in infants presenting to the emergency department.

The prevalence of respiratory syncytial virus in children presenting to US emergency departments with lower respiratory tract infection or apnea (N = 4172) was evaluated outside the traditional respiratory syncytial virus season (September to October and April to May) relative to January to February. The Mid-Atlantic and Southeast demonstrated positivity rates in September to October comparable with rates observed during January to February.

Distribution of respiratory syncytial virus subtypes A and B among infants presenting to the emergency department with lower respiratory tract infection or apnea.

Background: Respiratory syncytial virus (RSV), a leading viral respiratory pathogen worldwide, has 2 major subtypes, A and B.

Objective: To describe the temporal and geographic distribution and parameters of disease severity associated with RSV A and B in the United States.

Methods: A US multicenter active surveillance study was conducted in emergency departments (EDs) during 2 RSV seasons.

Genome sequencing and phylogenetic analysis of 39 human parainfluenza virus type 1 strains isolated from 1997-2010.

Thirty-nine human parainfluenza type 1 (HPIV-1) genomes were sequenced from samples collected in Milwaukee, Wisconsin from 1997-2010. Following sequencing, phylogenetic analyses of these sequences plus any publicly available HPIV-1 sequences (from GenBank) were performed. Phylogenetic analysis of the whole genomes, as well as individual genes, revealed that the current HPIV-1 viruses group into three different clades.

Update on influenza diagnostics: lessons from the novel H1N1 influenza A pandemic.

The menu of diagnostic tools that can be utilized to establish a diagnosis of influenza is extensive and includes classic virology techniques as well as new and emerging methods. This review of how the various existing diagnostic methods have been utilized, first in the context of a rapidly evolving outbreak of novel influenza virus and then during the different subsequent phases and waves of the pandemic, demonstrates the unique roles, advantages, and limitations of each of these methods. Rapid antigen tests were used extensively throughout the pandemic.

Whole genome sequencing and evolutionary analysis of human respiratory syncytial virus A and B from Milwaukee, WI 1998-2010.

Background: Respiratory Syncytial Virus (RSV) is the leading cause of lower respiratory-tract infections in infants and young children worldwide. Despite this, only six complete genome sequences of original strains have been previously published, the most recent of which dates back 35 and 26 years for RSV group A and group B respectively.

Methodology/principal Findings: We present a semi-automated sequencing method allowing for the sequencing of four RSV whole genomes simultaneously.

H1N1 hemagglutinin-inhibition seroprevalence in Emergency Department Health Care workers after the first wave of the 2009 influenza pandemic.

Study Objective: The 2009 H1N1 pandemic (H1N1pdm) virus has been associated with high rates of asymptomatic infections. Existing influenza infection control policies do not address potential transmission through exposure to asymptomatic infected individuals in health care settings. We conducted a seroprevalence study of H1N1pdm infection to determine whether health care workers (HCWs) in the emergency department showed increased evidence of infection during the first wave of the pandemic than that previously reported in adults in the community.

Phylogeography of the spring and fall waves of the H1N1/09 pandemic influenza virus in the United States.

Spatial variation in the epidemiological patterns of successive waves of pandemic influenza virus in humans has been documented throughout the 20th century but never understood at a molecular level. However, the unprecedented intensity of sampling and whole-genome sequencing of the H1N1/09 pandemic virus now makes such an approach possible. To determine whether the spring and fall waves of the H1N1/09 influenza pandemic were associated with different epidemiological patterns, we undertook a large-scale phylogeographic analysis of viruses sampled from three localities in the United States.

Epidemiologic Observations from Passive and Targeted Surveillance during the First Wave of the 2009 H1N1 Influenza Pandemic in Milwaukee, WI.

The first wave of the 2009 influenza H1N1 pandemic (H1N1pdm) in Milwaukee, WI has been recognized as the largest reported regional outbreak in the United States. The epidemiologic and clinical characteristics of this large first wave outbreak from April 28(th) 2009-July 25(th) 2009, studied using both passive and targeted surveillance methodologies are presented. A total of 2791 individuals with H1N1pdm infection were identified; 60 % were 5-18 years old.

Clinical and epidemiologic characteristics of children hospitalized with 2009 pandemic H1N1 influenza A infection.

Background: In 2009, pandemic H1N1 influenza caused significant morbidity and mortality worldwide. We describe the clinical and epidemiologic characteristics of children and adolescents hospitalized for 2009 H1N1 infections in Milwaukee, Wisconsin from April 2009 to August 2009.

Methods: We conducted retrospective chart reviews of hospitalized patients with laboratory-confirmed 2009 H1N1 infections.

Molecular diagnosis of respiratory viruses.

Respiratory tract viral infections are responsible for an incredible amount of morbidity and mortality throughout the world. Older diagnostic methods, such as tissue culture and serology, have been replaced with more advanced molecular techniques, such as PCR and reverse-transcriptase PCR, nucleic acid sequence-based amplification and loop-mediated isothermal amplification. These techniques are faster, have greater sensitivity and specificity, and are becoming increasingly accessible.

Persistence of adenovirus nucleic acids in nasopharyngeal secretions: a diagnostic conundrum.

Background: Polymerase chain reaction (PCR) assays increase the rate of viral detection in clinical specimens, compared with conventional virologic methods. Studies suggest that PCR may detect virus nucleic acid (NA) that persists in the respiratory tract.

Methods: We analyzed virologic data from children having frequent upper respiratory infections (URI), who were followed up in a longitudinal study.

The early diversification of influenza A/H1N1pdm.

Background Since its initial detection in April 2009, the A/H1N1pdm influenza virus has spread rapidly in humans, with over 5,700 human deaths. However, little is known about the evolutionary dynamics of H1N1pdm and its geographic and temporal diversification.Methods Phylogenetic analysis was conducted upon the concatenated coding regions of whole-genome sequences from 290 H1N1pdm isolates sampled globally between April 1 - July 9, 2009, including relatively large samples from the US states of Wisconsin and New York.

Development of a rapid automated influenza A, influenza B, and respiratory syncytial virus A/B multiplex real-time RT-PCR assay and its use during the 2009 H1N1 swine-origin influenza virus epidemic in Milwaukee, Wisconsin.

Rapid, semiautomated, and fully automated multiplex real-time RT-PCR assays were developed and validated for the detection of influenza (Flu) A, Flu B, and respiratory syncytial virus (RSV) from nasopharyngeal specimens. The assays can detect human H1N1, H3N2, and swine-origin (S-OIV) H1N1 Flu A viruses and were effectively used to distinguish Flu A infections (of all subtypes) from Flu B and RSV infections during the current S-OIV outbreak in Milwaukee, WI. The analytical limits of detection were 10(-2) to 10(1) TCID(50)/ml depending on the platform and analyte and showed only one minor cross-reaction among 23 common respiratory pathogens (intermittent cross-reaction to adenovirus at >10(7) TCID(50)/ml).