New aspects on human rhinovirus infections

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 1: acute respiratory infections

Acute illnesses affecting the respiratory tract are common and form a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. Acute respiratory illness (ARill) can broadly be classified as non-infective ARill and acute respiratory infections (ARinf). The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to ARinf in athletes. The International Olympic Committee (IOC) Medical and Scientific Commission appointed an international consensus group to review ARill (non-infective ARill and ARinf) in athletes. Six subgroups of the IOC Consensus group were initially established to review the following key areas of ARill in athletes: (1) epidemiology/risk factors for ARill, (2) ARinf, (3) non-infective ARill including ARill due to environmental exposure, (4) acute asthma and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport and (6) acute nasal/vocal cord dysfunction presenting as ARill. Several systematic and narrative reviews were conducted by IOC consensus subgroups, and these then formed the basis of sections in the consensus documents. Drafting and internal review of sections were allocated to 'core' members of the consensus group, and an advanced draft of the consensus document was discussed during a meeting of the main consensus core group in Lausanne, Switzerland on 11 to 12 October 2021. Final edits were completed after the meeting. This consensus document (part 1) focusses on ARinf, which accounts for the majority of ARill in athletes. The first section of this consensus proposes a set of definitions and classifications of ARinf in athletes to standardise future data collection and reporting. The remainder of the consensus paper examines a wide range of clinical considerations related to ARinf in athletes: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations, risks of infection during exercise, effects of infection on exercise/sports performance and return-to-sport guidelines.

Polyphenols and their potential role to fight viral diseases: An overview

Fruits, vegetables, spices, and herbs are a potential source of phenolic acids and polyphenols. These compounds are known as natural by-products or secondary metabolites of plants, which are present in the daily diet and provide important benefits to the human body such as antioxidant, anti-inflammatory, anticancer, anti-allergic, antihypertensive and antiviral properties, among others. Plentiful evidence has been provided on the great potential of polyphenols against different viruses that cause widespread health problems. As a result, this review focuses on the potential antiviral properties of some polyphenols and their action mechanism against various types of viruses such as coronaviruses, influenza, herpes simplex, dengue fever, and rotavirus, among others. Also, it is important to highlight the relationship between antiviral and antioxidant activities that can contribute to the protection of cells and tissues of the human body. The wide variety of action mechanisms of antiviral agents, such as polyphenols, against viral infections could be applied as a treatment or prevention strategy; but at the same time, antiviral polyphenols could be used to produce natural antiviral drugs. A recent example of an antiviral polyphenol application deals with the use of hesperidin extracted from Citrus sinensis. The action mechanism of hesperidin relies on its binding to the key entry or spike protein of SARS-CoV-2. Finally, the extraction, purification and recovery of polyphenols with potential antiviral activity, which are essential for virus replication and infection without side-effects, have been critically reviewed.

Molecular epidemiology and clinical impact of rhinovirus infections in adults during three epidemic seasons in 11 European countries (2007-2010)

Background

Differences in clinical impact between rhinovirus (RVs) species and types in adults are not well established. The objective of this study was to determine the epidemiology and clinical impact of the different RV species.

Methods

We conducted a prospective study of RVs infections in adults with acute cough/lower respiratory tract infection (LRTI) and asymptomatic controls. Subjects were recruited from 16 primary care networks located in 11 European countries between 2007 and 2010. RV detection and genotyping was performed by means of real time and conventional reverse-transcriptase polymerase chain reaction assays, followed by sequence analysis. Clinical data were obtained from medical records and patient symptom diaries.

Results

RVs were detected in 566 (19%) of 3016 symptomatic adults, 102 (4%) of their 2539 follow-up samples and 67 (4%) of 1677 asymptomatic controls. Genotyping was successful for 538 (95%) symptomatic subjects, 86 (84%) follow-up infections and 62 (93%) controls. RV-A was the prevailing species, associated with an increased risk of LRTI as compared with RV-B (relative risk (RR), 4.5; 95% CI 2.5 to 7.9; p<0.001) and RV-C (RR 2.2; 95% CI 1.2 to 3.9; p=0.010). In symptomatic subjects, RV-A loads were higher than those of RV-B (p=0.015). Symptom scores and duration were similar across species. More RV-A infected patients felt generally unwell in comparison to RV-C (p=0·023). Of the 140 RV types identified, five were new types; asymptomatic infections were associated with multiple types.

Interpretation

In adults, RV-A is significantly more often detected in cases with acute cough/LRTI than RV-C, while RV-B infection is often found in asymptomatic patients.

Viral respiratory infections in very low birthweight infants at neonatal intensive care unit: prospective observational study

BACKGROUND AND OBJECTIVE

Very low birthweight (VLBW) infants are highly susceptible to respiratory infections. Information about prevalence of viral respiratory infections (VRIs) in neonatal intensive care unit (NICU) is scarce. Recent evidence suggests short-term and long-term impact of VRI in morbidity of VLBW infants. The goal of this study is to conduct a VRI surveillance in VLBW infants during NICU admission to address the prevalence, type of viruses and associated clinical features.

METHODS

Prospective observational cohort study on infants below 32 gestational weeks admitted to a tertiary NICU during a 2-year period. Respiratory virus detection (influenza, parainfluenza, rhinovirus (hRV), enterovirus, respiratory syncytial virus, metapneumovirus, coronavirus, bocavirus and adenovirus) was performed by real time multiplex PCR assays in nasopharyngeal aspirates (NPAs), within the first 72 hours after birth and weekly, until discharge. Additional samples were taken if clinically indicated.

RESULTS

147 out of 224 eligible infants were enrolled. At least one positive NPA was found in 38% of the study cohort. Main viruses identified were hRV (58%) and adenovirus (31%). Among the 56 infants with positive NPA, 26 showed non-specific respiratory features in 58% (increased respiratory workload, tachypnoea, apnoea) or typical cold features in 38% (rhinorrhea, cough, fever), at least in one episode. Antibiotics were prescribed in 29% of cases. Positive infants showed higher rates of bronchopulmonary dysplasia (BPD), need for supplemental oxygen and mechanical ventilation, and had longer hospital stay. Cox regression analysis found BPD as an independent risk factor for viral infection (p<0.001) and symptomatic VRI (p<0.04).

CONCLUSIONS

Systematic surveillance in VLBW infants reports VRI is frequent, particularly by hRV. Asymptomatic infection is highly prevalent which is critical in the face of establishing appropriate preventive strategies. Infants with BPD are especially vulnerable to such infections.

Rhinoviruses in infancy and risk of immunoglobulin E sensitization

Previous data about the role of viruses in the development of allergic immunoglobulin E (IgE) sensitization are contradictory. The aim of this study was to determine the possible associations between exposure to different viruses (rhinovirus, enterovirus, norovirus, and parechovirus) during the first year of life and IgE sensitization. Viruses were analyzed from stool samples collected monthly from infants participating in a prospective birth cohort study. From that study, 244 IgE sensitized case children and 244 nonsensitized control children were identified based on their allergen-specific IgE antibody levels at the age of 6, 18, and 36 months. Stool samples (n = 4576) from the case and control children were screened for the presence of rhinovirus, enterovirus, norovirus, and parechovirus RNA by reverse transcription quantitative polymerase chain reaction. The study showed that rhinovirus was the most prevalent virus detected, present in 921 (20%) samples. None of the viruses were associated with IgE sensitization in the full cohort but after stratifying by sex, the number of rhinovirus positive samples was inversely associated with IgE sensitization in boys (odds ratio [OR]: 0.81; 95% confidence interval [CI]: 0.69-0.94; P = 0.006). There was also a temporal relation between rhinoviruses and IgE sensitization, as rhinovirus exposure during the first 6 months of life was associated with a reduced risk of subsequent IgE sensitization in boys (OR: 0.76; 95% CI: 0.6-0.94; P = 0.016). In conclusion, early exposure to rhinoviruses was inversely associated with IgE sensitization but this protective association was restricted to boys.

ROS Is Involved in Disruption of Tight Junctions of Human Nasal Epithelial Cells Induced by HRV16

OBJECTIVE

Rhinoviruses (RV), which are responsible for the majority of common colds, induce mucus overproduction, increased vascular permeability, and secondary bacterial infection. These symptoms are primarily caused by barrier function disruption, which is controlled by intercellular junctions. In this study, we investigated whether reactive oxygen species (ROS) are closely involved in tight junction disruption of primary human nasal epithelial (HNE) cells induced by infection of RV .

METHODS AND RESULTS

Incubation with RV resulted in disruption of tight junction proteins (ZO-1, E-cadherin, claudin-1, and occludin) in HNE cells. Pretreatment with diphenylene iodonium (DPI) decreased RV-induced disruption of tight junction in HNE cells. RV-induced generation of ROS was diminished by DPI. However, rotenone was not inhibited in HNE cells following incubation with RV. Rhinoviruses resulted in a marked decrease in protein phosphatases activity and an increase in protein tyrosine phosphorylation levels in HNE cells. Diphenylene iodonium inhibited the RV-induced inactivation of phosphatases and phosphorylation of protein tyrosine. In addition, inhibition of protein tyrosine phosphatases with phenylarsine oxide resulted in a marked decrease in protein phosphatase activity and disruption of tight junction proteins in HNE cells.

CONCLUSION

Our results suggest that ROS-mediated inhibition of phosphatases plays a crucial role in disruption of tight junctions in HNE cells by RV. The data suggest that RV infection may damage nasal epithelial barrier function.

LEVEL OF EVIDENCE

NA Laryngoscope, 128:E393-E401, 2018.

Etiology, Seasonality, and Clinical Features of Viral Respiratory Tract Infections in Children Hospitalized With Acute Bronchiolitis: A Single-Center Study

The purpose of this study was to evaluate the viral frequency, seasonality, and clinical and demographic features of patients hospitalized with acute bronchiolitis. A cross-sectional, descriptive study was performed in 316 infants younger than 2 years of age who were hospitalized for acute viral bronchiolitis. Respiratory tract infection agents were investigated with polymerase chain reaction (PCR). A total of 316 infants were included in this study. Of the 316 infants, at least one respiratory tract pathogen was detected in 75% (237/316). Respiratory syncytial virus (RSV) was the most common virus identified in 127 infants (40.1%) followed by rhinovirus (n = 78, 24.6%). In this study, where viral agents were determined via PCR in patients who were followed-up due to the diagnosis of acute bronchiolitis, RSV was detected as the most common agent, as in other studies. In almost half of the RSV-positive patients, RSV was accompanied by a second or third agent.

Review of the clinical significance of respiratory virus infections in newborn infants

Respiratory viruses have been recognised as causative agents for a wide spectrum of clinical manifestations and severe respiratory compromise in neonates during birth hospitalisation. Early‐life respiratory virus infections have also been shown to be associated with adverse long‐term consequences.

Conclusion

Preventing virus infections by intensifying hygiene measures and cohorting infected infants should be a major goal for neonatal intensive care units, as well as more common use of virus diagnostics. Active virus surveillance and long‐term follow‐up are needed to ascertain the causality and exact underlying mechanisms for adverse long‐term consequences.

RV-Typer: A Web Server for Typing of Rhinoviruses Using Alignment-Free Approach

Rhinoviruses (RV) are increasingly being reported to cause mild to severe infections of respiratory tract in humans. RV are antigenically the most diverse species of the genus Enterovirus and family Picornaviridae. There are three species of RV (RV-A, -B and -C), with 80, 32 and 55 serotypes/types, respectively. Antigenic variation is the main limiting factor for development of a cross-protective vaccine against RV.Serotyping of Rhinoviruses is carried out using cross-neutralization assays in cell culture. However, these assays become laborious and time-consuming for the large number of strains. Alternatively, serotyping of RV is carried out by alignment-based phylogeny of both protein and nucleotide sequences of VP1. However, serotyping of RV based on alignment-based phylogeny is a multi-step process, which needs to be repeated every time a new isolate is sequenced. In view of the growing need for serotyping of RV, an alignment-free method based on "return time distribution" (RTD) of amino acid residues in VP1 protein has been developed and implemented in the form of a web server titled RV-Typer. RV-Typer accepts nucleotide or protein sequences as an input and computes return times of di-peptides (k = 2) to assign serotypes. The RV-Typer performs with 100% sensitivity and specificity. It is significantly faster than alignment-based methods. The web server is available at http://bioinfo.net.in/RV-Typer/home.html.

Resveratrol inhibits rhinovirus replication and expression of inflammatory mediators in nasal epithelia

Human rhinoviruses (HRV), the cause of common colds, are the most frequent precipitants of acute exacerbation of asthma and chronic obstructive pulmonary disease, as well as causes of other serious respiratory diseases. No vaccine or antiviral agents are available for the prevention or treatment of HRV infection. Resveratrol exerts antiviral effect against different DNA and RNA viruses. The antiviral effect of a new resveratrol formulation containing carboxymethylated glucan was analyzed in H1HeLa cell monolayers and ex vivo nasal epithelia infected with HRV-16. Virus yield was evaluated by plaque assay and expression of viral capsid proteins by Western blot. IL-10, IFN-β, IL-6, IL-8 and RANTES levels were evaluated by ELISA assay. ICAM-1 was assessed by Western blot and immunofluorescence. Resveratrol exerted a high, dose-dependent, antiviral activity against HRV-16 replication and reduced virus-induced secretion of IL-6, IL-8 and RANTES to levels similar to that of uninfected nasal epithelia. Basal levels of IL-6 and RANTES were also significantly reduced in uninfected epithelia confirming an anti-inflammatory effect of the compound. HRV-induced expression of ICAM-1 was reversed by resveratrol. Resveratrol may be useful for a therapeutic approach to reduce HRV replication and virus-induced cytokine/chemokine production.

Infectivity assays of human rhinovirus-A and -B serotypes

Infectivity is a fundamental property of viral pathogens such as human rhinoviruses (HRVs). This chapter describes two methods for measuring the infectivity of HRV-A and -B serotypes: end point dilution (TCID50) assay and plaque assay. End point dilution assay is a quantal, not quantitative, assay that determines the dilution of the sample at which 50 % of the aliquots have infectious virus. It can be used for all the HRV-A and -B serotypes and related clinical isolates that grow in cell culture and induce cytopathic effect (CPE), degenerative changes in cells that are visible under a microscope. Plaque assay is a quantitative assay that determines the number of infectious units of a virus in a sample. After an infectious unit of virus infects one cell, the infected cell produces progeny viruses that then infect and kill a circle of adjacent cells. This circle of dead cells detaches from the dish and thus leaves a clear hole in a cell monolayer. Plaque assay works only for HeLa-adapted HRV-A and -B serotypes that can make visible plaques on the cell monolayer. Currently the end point dilution assay and plaque assay have not been developed for the newly discovered HRV-C.

Detection of enteroviruses and parechoviruses by a multiplex real-time RT-PCR assay

Detection of all enteroviruses while excluding cross-detection of rhinoviruses is challenging because of sequence similarities in the commonly used conserved targets for molecular assays. In addition, simultaneous detection and differentiation of enteroviruses and parechoviruses would be beneficial because of a similar clinical picture presented by these viruses. A sensitive and specific real-time RT-PCR protocol that can address these clinical needs would be valuable to molecular diagnostic laboratories. Here we report a multiplex nucleic acid based assay using hydrolysis probes targeting the 5′ non-translated region for the detection and differentiation of enteroviruses and parechoviruses without cross-detection of rhinoviruses. This assay has been shown to detect enteroviruses belonging to the different species in a variety of specimen types without detecting the different species of rhinoviruses. Laboratory validation shows the assay to be sensitive, specific, reproducible, easy to set up and uses generic cycling conditions. This assay can be implemented for diagnostic testing of patient samples in a high throughput fashion.

Common childhood viral infections

Infections caused by viruses are universal during childhood and adolescence. Clinicians will regularly care for children and adolescents who present with infections caused by a wide number of viral pathogens. These infections have varied presentations. Many infections may have clinical presentations that are specific to the infecting virus but present differently, based on the age and immunocompetence of the patient. Some children are directly impacted early in their lives when maternal disease results in an in utero infection (cytomegalovirus, rubella virus, or parvovirus B19). Other viruses may infect children in a predictable pattern as they grow older (rhinovirus or influenza virus). Fortunately, many viral infections frequently encountered in the past are no longer extant due to widespread immunization efforts. Recognition of these vaccine-preventable infections is important because outbreaks of some of these diseases (mumps or measles) continue to occur in the United States. Vigilance in vaccine programs against these viral agents can prevent their re-emergence. In addition, an increasing number of viral infections (herpes simplex virus, influenza virus, varicella zoster virus, or cytomegalovirus) can now be successfully treated with antiviral medications. Most viral infections in children result in self-limited illness and are treated symptomatically and infected children experience full recovery. This review will address the epidemiology, clinical presentation, diagnosis, treatment, and prevention of viral infections commonly encountered by the clinician.

Growth of human rhinovirus in H1-HeLa cell suspension culture and purification of virions

HeLa cell culture is the most widely used system for in vitro studies of the basic biology of human rhinovirus (HRV). It is also useful for making sufficient quantities of virus for experiments that require highly concentrated and purified virus. This chapter describes the protocols for producing a large amount of HeLa cells in suspension culture, using these cells to grow a large quantity of virus of HeLa-adapted HRV-A and -B serotypes, and making highly concentrated virus stock and highly purified virions. These purified HRV virions are free of cellular components and suitable for experiments that are sensitive to cellular contaminations.

Pathophysiology of Clinical Symptoms in Acute Viral Respiratory Tract Infections

In this article we discuss the pathophysiology of common symptoms of acute viral respiratory infections (e.g., sneezing, nasal discharge, sore throat, cough, muscle pains, malaise, and mood changes). Since clinical symptoms are not sufficient to determine the etiology of viral respiratory tract infections, we believe that the host defense mechanisms are critical for the symptomatology. Consequently, this review of literature is focused on the pathophysiology of respiratory symptoms regardless of their etiology. We assume that despite a high prevalence of symptoms of respiratory infection, their pathogenesis is not widely known. A better understanding of the symptoms' pathogenesis could improve the quality of care for patients with respiratory tract infections.

Molecular identification and quantification of human rhinoviruses in respiratory samples

PCR-based molecular assays have become standard diagnostic procedures for the identification and quantification of human rhinoviruses (HRVs) and other respiratory pathogens in most, if not all, clinical microbiology laboratories. Molecular assays are significantly more sensitive than traditional culture-based and serological methods. This advantage has led to the recognition that HRV infections are common causes for not only upper airway symptoms but also more severe lower respiratory illnesses. In addition, molecular assays improve turnaround time, can be performed by technicians with ordinary skills, and can easily be automated. This chapter describes two highly sensitive and specific PCR-based methods for identifying and quantifying HRVs. The first is a two-step PCR method for the detection and typing of HRV. The second is a pan-HRV real-time quantitative (q) PCR method for measuring viral loads in respiratory samples.

Prebiotic and probiotic supplementation prevents rhinovirus infections in preterm infants: a randomized, placebo-controlled trial

Background

Simple and safe strategies for the prevention of viral respiratory tract infections (RTIs) are needed.

Objective

We hypothesized that early prebiotic or probiotic supplementation would reduce the risk of virus-associated RTIs during the first year of life in a cohort of preterm infants.

Methods

In this randomized, double-blind, placebo-controlled trial (ClinicalTrials.gov no. NCT00167700), 94 preterm infants (gestational age, ≥32 + 0 and ≤36 + 6 weeks; birth weight, >1500 g) treated at Turku University Hospital, Turku, Finland, were allocated to receive oral prebiotics (galacto-oligosaccharide and polydextrose mixture, 1:1), a probiotic (Lactobacillus rhamnosus GG, ATCC 53103), or placebo (microcrystalline cellulose) between days 3 and 60 of life. The primary outcome was the incidence of clinically defined virus-associated RTI episodes confirmed from nasal swabs by using nucleic acid testing. Secondary outcomes were the severity and duration of RTIs.

Results

A significantly lower incidence of RTIs was detected in infants receiving prebiotics (rate ratio [RR], 0.24; 95% CI, 0.12-0.49; P < .001) or probiotics (RR, 0.50; 95% CI, 0.28-0.90; P = .022) compared with those receiving placebo. Also, the incidence of rhinovirus-induced episodes, which comprised 80% of all RTI episodes, was found to be significantly lower in the prebiotic (RR, 0.31; 95% CI, 0.14-0.66; P = .003) and probiotic (RR, 0.49; 95% CI, 0.24-1.00; P = .051) groups compared with the placebo group. No differences emerged among the study groups in rhinovirus RNA load during infections, duration of rhinovirus RNA shedding, duration or severity of rhinovirus infections, or occurrence of rhinovirus RNA in asymptomatic infants.

Conclusions

Gut microbiota modification with specific prebiotics and probiotics might offer a novel and cost-effective means to reduce the risk of rhinovirus infections.

Simultaneous detection and differentiation of human rhino- and enteroviruses in clinical specimens by real-time PCR with locked nucleic Acid probes

Human rhinoviruses (HRVs) and human enteroviruses (HEVs) are significant respiratory pathogens. While HRV infections are restricted to the respiratory tract, HEV infections may spread to secondary target organs. The method of choice for sensitive specific detection of these viruses is reverse transcription (RT)-PCR with primers targeting the conserved 5' noncoding region of the viral RNA. On the other hand, sequence similarities between HRVs and HEVs complicate their differential detection. In this study, we describe the use of locked nucleic acid (LNA) analogues in short double-dye probes which contained only two selectively HRV- or HEV-specific bases. The double-stranded DNA dye BOXTO (4-[6-(benzoxazole-2-yl-(3-methyl-)-2,3-dihydro-(benzo-1,3-thiazole)-2-methylidene)]-1-methyl-quinolinium chloride) was used with the LNA probes in a tricolor real-time PCR assay to allow specific detection of HRVs (probes labeled with 6-carboxyfluorescein [FAM] [green]) and HEVs (Cy5 [red]) with additional melting curve analysis (BOXTO [yellow]). The functionality of the probes was validated in PCR and RT-PCR assays using plasmids containing viral cDNA, quantified viral RNA transcripts, cultivated rhino- and enterovirus prototypes, and clinical specimens. Of 100 HRV and 63 HEV prototypes, the probes correctly identified all HEVs except one that produced only a BOXTO signal. Among 118 clinical specimens with sequencing results, concordant results were obtained for 116 specimens. Two specimens were reactive with both probes, but sequencing yielded only a single virus. Real-time PCR with LNA probes allowed sensitive group-specific identification of HRVs and HEVs and would enable relative copy number determination. The assay is suitable for rapid and accurate differential detection of HRVs and HEVs in a diagnostic laboratory setting.