Cost burden of viral respiratory infections: issues for formulary decision makers

Antibiotic prescriptions associated with a diagnosis of acute nasopharyngitis by GPs in France: a retrospective study

BACKGROUND

Nasopharyngitis is a common viral infection that has led to an overuse of prescription drugs, in particular antibiotics, which are not indicated for this condition.

AIM

The purpose of this study was to describe drug prescriptions for patients with a diagnosis of acute rhinopharyngitis in general practices in France.

DESIGN & SETTING

Retrospective study of 1 067 403 prescriptions for a diagnosis of nasopharyngitis issued by 2637 physicians to 754 476 patients living in metropolitan France.

METHOD

The data were sourced from the prescription software, Cegedim, for the period 1 January 2018 to 31 December 2021 and analysed according to patients' and physicians' ages.

RESULTS

A total of 2 591 584 medications were prescribed by GPs, with a median of three medications per patient. A total of 171 540 courses of antibiotics were prescribed (16% prescription rates), with amoxicillin being the most frequently prescribed (102 089 prescriptions; 59.5% of antibiotic prescriptions). Amoxicillin prescription increased in extreme age groups (18.2% of visits in those aged 9 years and under, and 10.0% of visits in those aged over 80 years, while patients aged 20-29-years were prescribed amoxicillin in just 2.9% of visits), and more prescriptions are issued by older doctors (GPs older than 70 years prescribed antibiotics in 26.4% of visits versus 3.2% of visits by GPs aged under 29 years).

CONCLUSION

Nasopharyngitis is frequently a cause of therapeutic over-prescriptions including antibiotics, with an antibiotic prescription rate of 16%. Additional research is required to enhance our understanding of factors linked to drug prescriptions.

RVdb: a comprehensive resource and analysis platform for rhinovirus research

Rhinovirus (RV), a prominent causative agent of both upper and lower respiratory diseases, ranks among the most prevalent human respiratory viruses. RV infections are associated with various illnesses, including colds, asthma exacerbations, croup and pneumonia, imposing significant and extended societal burdens. Characterized by a high mutation rate and genomic diversity, RV displays a diverse serological landscape, encompassing a total of 174 serotypes identified to date. Understanding RV genetic diversity is crucial for epidemiological surveillance and investigation of respiratory diseases. This study introduces a comprehensive and high-quality RV data resource, designated RVdb (http://rvdb.mgc.ac.cn), covering 26 909 currently identified RV strains, along with RV-related sequences, 3D protein structures and publications. Furthermore, this resource features a suite of web-based utilities optimized for easy browsing and searching, as well as automatic sequence annotation, multiple sequence alignment (MSA), phylogenetic tree construction, RVdb BLAST and a serotyping pipeline. Equipped with a user-friendly interface and integrated online bioinformatics tools, RVdb provides a convenient and powerful platform on which to analyse the genetic characteristics of RVs. Additionally, RVdb also supports the efforts of virologists and epidemiologists to monitor and trace both existing and emerging RV-related infectious conditions in a public health context.

Antibiotic prescription in ambulatory care for COVID-19 patients: a cohort analysis in four European countries

OBJECTIVE

To analyse antibiotic prescription rates in ambulatory care for COVID-19 patients by general practitioners (GPs) in four European countries.

METHODS

A total of 4,513,955 anonymised electronic prescribing records of 3656 GPs in four European countries were analysed. Diagnosis and prescriptions were retrieved. Antibiotic prescription rates during COVID-19 consultations were analysed and compared between France, the UK, Belgium and Romania.

RESULTS

Overall prescription rate was in France and Belgium (6.66 and 7.46%). However, analysing median GP prescribing rates, we found that 33.9% of the GPs in Belgium prescribed antibiotics with a median of 16 prescriptions per 100 COVID-19 consultations, while 55.21% of the GPs in France prescribed a median of 8 antibiotic prescriptions per 100 COVID-19 consultations. Overall antibiotic prescription rates were less in Romania than in the UK (22% vs 32%); however, 73% of the Romanian GPs vs 57% of the British GPs prescribed antibiotics. Depending on the country, the proportion of each type of antibiotic was statistically different, with the proportion of azithromycin being more than 50% of all antibiotics in each country except for the UK where it was less than 1%.

CONCLUSION

Both individual GPs prescribing patterns in addition to overall consumption patterns should be analysed in order to implement a tailored antimicrobial stewardship programme. Furthermore, antibiotic prescribing rates in COVID-19 are lower than other respiratory tract infections.

Genetic diversity and characterization of rhinoviruses from Chinese clinical samples with a global perspective

IMPORTANCE

Based on clinical samples collected in China, we detected and reported 22 types for the first time in China, as well as three types for the first time in Asia, and reported their genetic characteristics and diversity. We identified a novel type of Rhinovirus (RV), A110, highlighting its unique genetic features. We annotated the genomic structure and serotype of all the existing RV sequences in the database, and four novel RV types were identified and their genetic diversity reported. Combined with the sequence annotation, we constructed a complete VP1 data set of RV and conducted the first large-scale evolutionary dynamics analysis of RV. Based on a high-quality data set, we conducted a comprehensive analysis of the guanine-cytosine (GC) content variations among serotypes of RVs. This study provides crucial theoretical support and valuable data for understanding RV's genetic diversity and developing antiviral strategies.

Ingredients of Vicks VapoRub inhibit rhinovirus-induced ATP release

Background

Over-the-counter therapies, such as Vicks VapoRub, are frequently used in the management of upper respiratory tract infection symptoms. Of these, acute cough is the most bothersome; however, the mechanisms involved have not been fully elucidated. The temperature-sensitive transient receptor potential (TRP) channels, including TRPA1, TRPV1, TRPM8 and TRPV4, are potential candidates. TRPV4 is also thought to be involved in cough through the TRPV4-ATP-P2X3 pathway. Here, we hypothesise that Vicks VapoRub ingredients (VVRIs) modulate the TRP cough channels.

Methods

Stably transfected HEK cells expressing TRP channels were challenged with VVRIs, individually or in combination, and the agonist and antagonist effects were measured using calcium signalling responses. In addition, rhinovirus serotype-16 (RV16)-infected A549 airway epithelial cells were pre-incubated with individual or combinations of VVRIs prior to hypotonic challenge and extracellular ATP release analysis.

Results

Calcium signalling reconfirmed some previously defined activation of TRP channels by specific VVRIs. The combined VVRIs containing menthol, camphor and eucalyptus oil activated TRPV1, TRPV4, TRPM8 and untransfected wild-type HEK293 cells. However, pre-incubation with VVRIs did not significantly inhibit any of the channels compared with the standard agonist responses. Pre-incubation of RV16-infected A549 cells with individual or combined VVRIs, except menthol, resulted in a 0.45-0.55-fold reduction in total ATP release following hypotonic stimulation, compared with infected cells not treated with VVRIs.

Conclusion

These findings suggest that some VVRIs may reduce symptoms associated with upper respiratory tract infection by modulating specific TRP receptors and by reducing RV16-induced ATP release.

Medicinal Plants for Viral Respiratory Diseases: A Systematic Review on Persian Medicine

Introduction

Many medicinal plants have been introduced in Persian medicine references for various respiratory disorders. Considering the growing interest in herbal medicines, this review aimed to introduce medicinal herbs recommended by Persian Medicine (PM) references for respiratory diseases and to discuss their activity against respiratory viruses.

Methods

The medicinal plants recommended for respiratory disorders were extracted from the main PM textbooks. Subsequently, their activity against respiratory viruses was systematically investigated via queries of scientific databases.

Results

Searching PM references for medicinal plants used in the management of respiratory disorders yielded 45 results. Of them, 18 possess antiviral activity against respiratory viruses. There were 29 in vitro studies (including studies on human cell lines) and 5 in vivo studies.

Conclusion

This research demonstrated that many of the medicinal plants mentioned for the respiratory diseases in PM have considerable activity against respiratory viruses. However, human studies regarding the reported medicinal plants are scarce.

Cold exposure impairs extracellular vesicle swarm-mediated nasal antiviral immunity

BACKGROUND

The human upper respiratory tract is the first site of contact for inhaled respiratory viruses and elaborates an array of innate immune responses. Seasonal variation in respiratory viral infections and the importance of ambient temperature in modulating immune responses to infections have been well recognized; however, the underlying biological mechanisms remain understudied.

OBJECTIVE

We investigated the role of nasal epithelium-derived extracellular vesicles (EVs) in innate Toll-like receptor 3 (TLR3)-dependent antiviral immunity.

METHODS

We evaluated the secretion and composition of nasal epithelial EVs after TLR3 stimulation in human autologous cells and fresh human nasal mucosal surgical specimens. We also explored the antiviral activity and mechanisms of TLR3-stimulated EVs against respiratory viruses as well as the effect of cool ambient temperature on TLR3-dependent antiviral immunity.

RESULTS

We found that polyinosinic:polycytidylic acid, aka poly(I:C), exposure induced a swarm-like increase in the secretion of nasal epithelial EVs via the TLR3 signaling. EVs participated in TLR3-dependent antiviral immunity, protecting the host from viral infections through both EV-mediated functional delivery of miR-17 and direct virion neutralization after binding to virus ligands via surface receptors, including LDLR and ICAM-1. These potent antiviral immune defense functions mediated by TLR3-stimulated EVs were impaired by cold exposure via a decrease in total EV secretion as well as diminished microRNA packaging and antiviral binding affinity of individual EV.

CONCLUSION

TLR3-dependent nasal epithelial EVs exhibit multiple innate antiviral mechanisms to suppress respiratory viral infections. Furthermore, our study provides a direct quantitative mechanistic explanation for seasonal variation in upper respiratory tract infection prevalence.

The COPD Foundation's COPD360Net Initiative Approach to Patient-Centric Drug Development: A Case Study in Using Patient Surveys to Inform New Treatments for Viral Respiratory Infections

Patient-centric drug development is crucial to creating treatments that address unmet patient needs but is often ignored. The COPD Foundation's COPD360Net^® includes a multistakeholder approach for operationalizing patient-centric development of treatments where patients, caregivers, scientists, and clinicians review opportunities based on scientific merit, potential to address an unmet need, and feasibility of adoption. COPD360Net deploys large-scale online community surveys to review profiles of potential therapies based on those criteria. This approach was implemented to inform the development of an intranasal spray to prevent viral respiratory infections (VRIs), a major cause of exacerbations in people with chronic lung diseases. Insights included: Of the 376 respondents with COPD surveyed, frequent exacerbators reported strong interest in a new type of antiviral nasal spray to prevent VRI.Patient survey and advisory committee insights demonstrated that a pan antiviral nasal spray has potential high value to both clinicians and patients and informed the COPD360Net decision to partner on its development.Including patient perspectives from the outset can be conducted efficiently by mobilizing an engaged online patient community.

Modulation of transient receptor potential (TRP) channels by plant derived substances used in over-the-counter cough and cold remedies

BACKGROUND

Upper respiratory tract infections (URTIs) impact all age groups and have a significant economic and social burden on society, worldwide. Most URTIs are mild and self-limiting, but due to the wide range of possible causative agents, including Rhinovirus (hRV), Adenovirus, Respiratory Syncytial Virus (RSV), Coronavirus and Influenza, there is no single and effective treatment. Over-the-counter (OTC) remedies, including traditional medicines and those containing plant derived substances, help to alleviate symptoms including inflammation, pain, fever and cough.

PURPOSE

This systematic review focuses on the role of the major plant derived substances in several OTC remedies used to treat cold symptoms, with a particular focus on the transient receptor potential (TRP) channels involved in pain and cough.

METHODS

Literature searches were done using Pubmed and Web of Science, with no date limitations, using the principles of the PRISMA statement. The search terms used were 'TRP channel AND plant compound', 'cough AND plant compound', 'cough AND TRP channels AND plant compound', 'cough AND P2X3 AND plant compound' and 'P2X3 AND plant compound' where plant compound represents menthol or camphor or eucalyptus or turpentine or thymol.

RESULTS

The literature reviewed showed that menthol activates TRPM8 and may inhibit respiratory reflexes reducing irritation and cough. Menthol has a bimodal action on TRPA1, but inhibition may have an analgesic effect. Eucalyptus also activates TRPM8 and inhibits TRPA1 whilst down regulating P2X3, aiding in the reduction of cough, pain and airway irritation. Camphor inhibits TRPA1 and the activation of TRPM8 may add to the effects of menthol. Activation of TRPV1 by camphor, may also have an analgesic effect.

CONCLUSIONS

The literature suggests that these plant derived substances have multifaceted actions and can interact with the TRP 'cough' receptors. The plant derived substances used in cough and cold medicines have the potential to target multiple symptoms experienced during a cold.

Clinical characteristics, outcomes, and seasonality of acute respiratory infection associated with single and codetected rhinovirus species among hospitalized children in Amman, Jordan

Rhinovirus (RV)-specific surveillance studies in the Middle East are limited. Therefore, we aimed to study the clinical characteristics, outcomes, and seasonality of RV-associated acute respiratory infection among hospitalized young children in Jordan. We conducted a prospective viral surveillance study and enrolled children <2 years old admitted to a large public hospital in Amman, Jordan (2010-2013). Demographic and clinical data were collected by structured interviews and chart abstractions. Nasal and/or throat swabs were collected and tested for a panel of respiratory viruses, and RV genotyping and speciation was performed. At least one virus was detected in 2641/3168 children (83.4%). RV was the second most common virus detected (n = 1238; 46.9%) and was codetected with another respiratory virus in 730 cases (59.0%). Children with RV codetection were more likely than those with RV-only detection to have respiratory distress but had similar outcomes. RV-A accounted for about half of RV-positive cases (54.7%), while children with RV-C had a higher frequency of wheezing and reactive airway disease. RV was detected year-round and peaked during winter. In conclusion, though children with RV codetection had worse clinical findings, neither codetection nor species affected most clinical outcomes.

Ivy leaves extract EA 575 in the treatment of cough during acute respiratory tract infections: meta-analysis of double-blind, randomized, placebo-controlled trials

Ivy leaves extracts have been used successfully to treat acute cough, and data from well-controlled trials is accumulating. We present a meta-analysis of two double-blind, randomized, placebo-controlled trials. Patients with acute respiratory tract infection (ARTI) received ivy leaves dry extract EA 575 (n = 228) or placebo (n = 162) for 7 days, followed by a 7-day period without treatment. The main efficacy outcome was the Bronchitis Severity Score (BSS). Individual patient data meta-analyses were performed using mixed models for repeated measures, analysis of covariance and logistic ordinal regression. Significant BSS differences between EA 575 and placebo occurred already after 2 days and increased until treatment end, with BSS reductions of 8.6 ± 0.2 and 6.2 ± 0.2 (marginal means ± SEM; p < 0.001). The score reduction for placebo after 7 days was comparable to that for EA 575 after 4 days. In the EA 575 group, the proportion of cough-free patients was 18.1% at treatment end and 56.2% at end of follow-up, compared to 9.3% and 25.6% for placebo, respectively. Adverse event rates for EA 575 and placebo were comparable. EA 575 reduces effectively the intensity of acute cough associated with ARTIs and leads to a significant acceleration of recovery. No safety signals were observed.

Influence factors for upper respiratory tract infection in Chinese rural children: A cross-sectional study

AIM

The prevalence rate of upper respiratory tract infection (URTI) is high in children. Influencing factors for URTI have been reported in Chinese urban children, but those have not been explored in rural children. In China, children in the rural areas are a disadvantaged group. Therefore, this study aims to explore influencing factors for URTI in Chinese rural children.

METHODS

This is a cross-sectional study based on the 1991-2015 China Health and Nutrition Survey (CHNS). In total, 5,289 children were eligible for the analysis, including 3,684 rural children and 1,605 urban children. The generalized estimating equation was used to determine the influencing factors, and results were expressed as odds ratios (ORs) with 95% confidence intervals (95% CIs).

RESULTS

The results showed that rural children aged 7-12 and 13-17 years had lower odds of URTI than those aged 0-1 year, with OR value of 0.17 (95% CI, 0.11-0.27) and 0.12 (95% CI, 0.08-0.19), respectively. Compared with uneducated mothers, those with education level of primary school (OR: 0.59, 95% CI, 0.42-0.84), lower middle school (OR: 0.53, 95% CI, 0.38-0.73), and upper middle school and technical school (OR: 0.62, 95% CI, 0.40-0.95) were associated with the lower odds of URTI in rural children. Children, whose mothers were office workers, had 46% lower odds of URTI than those with farmer mothers (OR: 0.54, 95% CI, 0.34-0.84).

CONCLUSIONS

This study found that mother's education level, children's age, and mother's occupation were significant influencing factors for URTI, which suggested the importance to improve mother's health-related knowledge and working conditions in Chinese rural areas.

Respiratory Viral and Bacterial Factors That Influence Early Childhood Asthma

Asthma is a chronic respiratory condition characterised by episodes of shortness of breath due to reduced airway flow. The disease is triggered by a hyperreactive immune response to innocuous allergens, leading to hyper inflammation, mucus production, changes in structural cells lining the airways, and airway hyperresponsiveness. Asthma, although present in adults, is considered as a childhood condition, with a total of about 6.2 million children aged 18 and below affected globally. There has been progress in understanding asthma heterogeneity in adults, which has led to better patient stratification and characterisation of multiple asthma endotypes with distinct, but overlapping inflammatory features. The asthma inflammatory profile in children is not well-defined and heterogeneity of the disease is less described. Although many factors such as genetics, food allergies, antibiotic usage, type of birth, and cigarette smoke exposure can influence asthma development particularly in children, respiratory infections are thought to be the major contributing factor in poor lung function and onset of the disease. In this review, we focus on viral and bacterial respiratory infections in the first 10 years of life that could influence development of asthma in children. We also review literature on inflammatory immune heterogeneity in asthmatic children and how this overlaps with early lung development, poor lung function and respiratory infections. Finally, we review animal studies that model early development of asthma and how these studies could inform future therapies and better understanding of this complex disease.

Seasonal Coronaviruses and Other Neglected Respiratory Viruses: A Global Perspective and a Local Snapshot

Respiratory viral infections are the leading cause of morbidity and mortality in the world; however, there are several groups of viruses that are insufficiently routinely sought for, and can thus be considered neglected from a diagnostic and clinical standpoint. Timely detection of seasonality of certain respiratory viruses (e.g., enveloped viruses such as seasonal coronaviruses) in the local context can aid substantially in targeted and cost-effective utilization of viral diagnostic approaches. For the other, non-enveloped and year-round viruses (i.e., rhinovirus, adenovirus, and bocavirus), a continuous virological diagnosis needs to be implemented in clinical laboratories to more effectively address the aetiology of respiratory infections, and assess the overall impact of these viruses on disease burden. While the coronavirus disease 2019 (COVID-19) pandemic is still actively unfolding, we aimed to emphasize the persistent role of seasonal coronaviruses, rhinoviruses, adenoviruses and bocaviruses in the aetiology of respiratory infections. Consequently, this paper concentrates on the burden and epidemiological trends of aforementioned viral groups on a global level, but also provides a snapshot of their prevalence patterns in Croatia in order to underscore the potential implications of viral seasonality. An overall global prevalence in respiratory tract infections was found to be between 0.5 and 18.4% for seasonal coronaviruses, between 13 and 59% for rhinoviruses, between 1 and 36% for human adenoviruses, and between 1 and 56.8% for human bocaviruses. A Croatian dataset on patients with respiratory tract infection and younger than 18 years of age has revealed a fairly high prevalence of rhinoviruses (33.4%), with much lower prevalence of adenoviruses (15.6%), seasonal coronaviruses (7.1%), and bocaviruses (5.3%). These insights represent a relevant discussion point in the context of the COVID-19 pandemic where the testing of non-SARS-CoV-2 viruses has been limited in many settings, making the monitoring of disease burden associated with other respiratory viruses rather difficult.

Global burden of upper respiratory infections in 204 countries and territories, from 1990 to 2019

BACKGROUND

Upper respiratory infections (URIs) are among the most common diseases. However, the related burden has not been comprehensively evaluated. Thus, we designed the present study to describe the global and regional burden of URIs from 1990 to 2019.

METHODS

A secondary analysis was performed on the incidence, mortality, and disability-adjusted life years (DALYs) of URIs in different sex and age groups, from 21 geographic regions, 204 countries and territories, between 1990 and 2019, using the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Countries and territories were categorized according to Socio-demographic Index (SDI) quintiles.

FINDINGS

Globally, the incident cases of URIs reached 17·2 (95% uncertainty interval: 15·4 to 19·3) billion in 2019, which accounted for 42·83% (40·01% to 45·77%) cases from all causes in the GBD 2019 study. The age-standardized incidence rate remained stable from 1990 to 2019, while significant decreases were found in the mortality and DALY rate. The highest age-standardized incidence rates from 1990 to 2019 and the highest age-standardized DALY rates after 2011 were observed in high SDI regions. Among all the age groups, children under five years old suffered from the highest incidence and DALY rates, both of which were decreased with increasing age. Fatal consequences of URIs occurred mostly in the elderly and children under five years old.

INTERPRETATION

The present study provided comprehensive estimates of URIs burden for the first time. Our findings, highlighting the substantial incidence and considerable DALYs due to URIs, are expected to attract more attention to URIs and provide future explorations in the prevention and treatment with epidemiological evidence.

FUNDING

The study was funded by the National Natural Science Foundation of China (81770057).

ICAM-1 induced rearrangements of capsid and genome prime rhinovirus 14 for activation and uncoating

Medical visits and missed days of school and work caused by rhinoviruses cost tens of billions of US dollars annually. Currently, there are no antivirals against rhinoviruses, and the available treatments only treat the symptoms. Here, we present the molecular structure of human rhinovirus 14 in complex with its cellular receptor intercellular adhesion molecule 1. The binding of the virus to its receptor initiates the infection. Knowledge of the structure of the human rhinovirus 14–intercellular adhesion molecule 1 interface and mechanism of interaction provides the basis for the design of compounds that may block the binding of rhinoviruses to receptors and thus prevent infection.

Most rhinoviruses, which are the leading cause of the common cold, utilize intercellular adhesion molecule-1 (ICAM-1) as a receptor to infect cells. To release their genomes, rhinoviruses convert to activated particles that contain pores in the capsid, lack minor capsid protein VP4, and have an altered genome organization. The binding of rhinoviruses to ICAM-1 promotes virus activation; however, the molecular details of the process remain unknown. Here, we present the structures of virion of rhinovirus 14 and its complex with ICAM-1 determined to resolutions of 2.6 and 2.4 Å, respectively. The cryo-electron microscopy reconstruction of rhinovirus 14 virions contains the resolved density of octanucleotide segments from the RNA genome that interact with VP2 subunits. We show that the binding of ICAM-1 to rhinovirus 14 is required to prime the virus for activation and genome release at acidic pH. Formation of the rhinovirus 14–ICAM-1 complex induces conformational changes to the rhinovirus 14 capsid, including translocation of the C termini of VP4 subunits, which become poised for release through pores that open in the capsids of activated particles. VP4 subunits with altered conformation block the RNA–VP2 interactions and expose patches of positively charged residues. The conformational changes to the capsid induce the redistribution of the virus genome by altering the capsid–RNA interactions. The restructuring of the rhinovirus 14 capsid and genome prepares the virions for conversion to activated particles. The high-resolution structure of rhinovirus 14 in complex with ICAM-1 explains how the binding of uncoating receptors enables enterovirus genome release.

Medical Cost of Upper Respiratory Tract Infections in Children in Ambulatory Care

OBJECTIVE

The aim of this study was to estimate the direct cost per episode and the annual cost for upper respiratory tract infection (URTI) in children in Ambulatory Health Centers of the Ministry of Public Health (MSP) of Ecuador.

METHODS

A cost of illness study with a provider perspective was carried out through a micro-costing of health resources and valuated in international dollars. Medical visits, laboratory tests, imaging examinations, and other procedures were valued using the tariff framework of services for the National Health System, and for prescribed medication a reported cost registry of pharmacy purchases made in the year of study was used.

RESULTS

We included 380 electronic health records of children. We found a re-consultation rate of 22.89%, a medicine prescription rate of 95.52%, and an antibiotic prescription rate of 45.26%. The first medical consultation accounted for 71.9% of the total cost of URTI, the following visits accounted for 11.82%, and medication accounted for 14.68%. Antibiotics accounted for 58.92% of the total cost of medication.

CONCLUSION

The direct medical cost to the MSP of Ecuador of 1 episode of URTI in children in primary care was around I$37.28 (2017 dollars) (95% CI: I$35.81-I$38.75). The total cost of URTI cases in children to the MSP in 2017 was at least I$50.478 million (2017 dollars) (95% CI I$48.527m-I$52.523m). Re-consultation and the prescription of medication represent an important component of the direct cost of medical care of URTI.

Inhibition of viral RNA-dependent RNA polymerases with clinically relevant nucleotide analogs

The treatment of viral infections remains challenging, in particular in the face of emerging pathogens. Broad-spectrum antiviral drugs could potentially be used as a first line of defense. The RNA-dependent RNA polymerase (RdRp) of RNA viruses serves as a logical target for drug discovery and development efforts. Herein we discuss compounds that target RdRp of poliovirus, hepatitis C virus, influenza viruses, respiratory syncytial virus, and the growing data on coronaviruses. We focus on nucleotide analogs and mechanisms of action and resistance.

Cost of inappropriate antimicrobial use for upper respiratory infection in Japan

BACKGROUND

Antibiotics are often prescribed inappropriately to patients with upper respiratory infection (URI) in ambulatory care settings; however, the economic burden of such prescription has not been quantitatively assessed. Here, we aimed to evaluate the additional cost of antimicrobial prescription for URI at the population level in Japan.

METHODS

We conducted a retrospective observational survey using longitudinal claims data between 2013 and 2016 obtained from JMDC Claims Database, which contains data from 5·1 million corporate employees and family members under the age of 65 years. Appropriateness of antibiotic prescription was assessed by a panel of six infectious disease physicians according to ICD-10 code in JMDC Claims Database. Total additional cost of antibiotic prescription for URI at the national level was estimated by weighting of age-structured population data.

RESULTS

The annual additional cost of inappropriate antibiotic prescription for URI was estimated at 423·6 (95% CI: 416·8-430·5) million USD in 2013, 340·9 (95% CI: 335·7-346·2) million USD in 2014, 349·9 (95% CI: 344·5-355·3) million USD in 2015, and 297·1 (95% CI: 292·4-301·9) million USD in 2016. Three classes of broad-spectrum oral antibiotics (third-generation cephalosporins, macrolides, and fluoroquinolones) accounted for > 90% of the total additional cost.

CONCLUSIONS

Although a decreasing trend was observed, annual additional costs of inappropriate antibiotic prescriptions for URI could be a substantial economic burden in Japan. Appropriately prescribing broad-spectrum oral antibiotics might be an important issue to reduce unnecessary medical costs in Japanese ambulatory care.

T-bet+ Memory B Cells Link to Local Cross-Reactive IgG upon Human Rhinovirus Infection

Human rhinoviruses cause the common cold and exacerbate chronic respiratory diseases. Although infection elicits neutralizing antibodies, these do not persist or cross-protect across multiple rhinovirus strains. To analyze rhinovirus-specific B cell responses in humans, we developed techniques using intact RV-A16 and RV-A39 for high-throughput high-dimensional single-cell analysis, with parallel assessment of antibody isotypes in an experimental infection model. Our approach identified T-bet+ B cells binding both viruses that account for ∼5% of CXCR5- memory B cells. These B cells infiltrate nasal tissue and expand in the blood after infection. Their rapid secretion of heterotypic immunoglobulin G (IgG) in vitro, but not IgA, matches the nasal antibody profile post-infection. By contrast, CXCR5+ memory B cells binding a single virus are clonally distinct, absent in nasal tissue, and secrete homotypic IgG and IgA, mirroring the systemic response. Temporal and spatial functions of dichotomous memory B cells might explain the ability to resolve infection while rendering the host susceptible to re-infection.

A review on epidemiology and impact of human metapneumovirus infections in children using TIAB search strategy on PubMed and PubMed Central articles

Acute respiratory tract infections (ARTI) contribute to morbidity and mortality in children globally. Viruses including human metapneumovirus (hMPV) account for most ARTIs. The virus causes upper and lower respiratory tract infections mostly in young children and contributes to hospitalization of individuals with asthma,chronic obstructive pulmonary diseases and cancer. Moreover, hMPV pauses a considerable socio-economic impact creating a substantial disease burden wherever it has been studied, although hMPV testing is relatively new in many countries. We aimed to comprehensively analyze the epidemiological aspects including prevalence, disease burden and seasonality of hMPV infections in children in the world. We acquired published data extracted from PubMed and PubMed Central articles using the title and abstract (TIAB)search strategy for the major key words on hMPV infections from 9/54 African, 11/35 American, 20/50 Asian, 2/14 Australian/Oceanian and 20/51 European countries. According to the findings of this review, the prevalence of hMPV infection ranges from 1.1 to 86% in children of less than 5 years of age globally. Presence of many hMPV genotypes (A1, A2, B1, B2) and sub-genotypes (A2a, A2b, A2c, B2a, B2b) suggests a rapid evolution of the virus with limited influence by time and geography. hMPV infection mostly affects children between 2 to 5 years of age. The virus is active throughout the year in the tropics and epidemics occur during the winter and spring in temperate climates, contributing to a substantial disease burden globally.

Treatment of signs and symptoms of the common cold using EPs 7630 - results of a meta-analysis

The efficacy of Pelargonium sidoides preparation EPs 7630 in the common cold (CC) was assessed by performing meta-analyses of randomized, double-blind, placebo-controlled trials. Mean differences (MD) and risk ratios (RR) with their 95% confidence intervals (CI) were computed. Five trials with a total of 833 patients were included. All trials had a treatment period of ten days with visits at days 3, 5, and 10 after baseline and used a ten-symptom Cold Intensity Score (CIS) as the primary outcome. Significant differences favoring EPs 7630 were observed for total CIS reduction (day 5: MD = -2·30; 95%CI = -4·12,-0·49; day 10: MD = -1·16; 95%CI = -2·22,-0·10), proportion of patients with substantial improvement (day 5: RR = 1·73; day 10: RR = 1·06) and complete remission (day 5: RR = 2·52; day 10: RR = 2·13). Subjects treated with EPs 7630 missed fewer days at work, used less paracetamol and had an improved sleep quality. No serious adverse reactions to EPs 7630 were reported. The results support the efficacy of EPs 7630 in adults with CC.

Rhinovirus induces an anabolic reprogramming in host cell metabolism essential for viral replication

Rhinoviruses (RVs) are responsible for the majority of upper airway infections; despite their high prevalence and the resulting economic burden, effective treatment is lacking. We report here that RV induces metabolic alterations in host cells, which offer an efficient target for antiviral intervention. We show that RV-infected cells rapidly up-regulate glucose uptake in a PI3K-dependent manner. In parallel, infected cells enhance the expression of the PI3K-regulated glucose transporter GLUT1. In-depth metabolomic analysis of RV-infected cells revealed a critical role of glucose mobilization from extracellular and intracellular pools via glycogenolysis for viral replication. Infection resulted in a highly anabolic state, including enhanced nucleotide synthesis and lipogenesis. Consistently, we observed that glucose deprivation from medium and via glycolysis inhibition by 2-deoxyglucose (2-DG) potently impairs viral replication. Metabolomic analysis showed that 2-DG specifically reverts the RV-induced anabolic reprogramming. In addition, treatment with 2-DG inhibited RV infection and inflammation in a murine model. Thus, we demonstrate that the specific metabolic fingerprint of RV infection can be used to identify new targets for therapeutic intervention.

Neonatal Immunity, Respiratory Virus Infections, and the Development of Asthma

Infants are exposed to a wide range of potential pathogens in the first months of life. Although maternal antibodies acquired transplacentally protect full-term neonates from many systemic pathogens, infections at mucosal surfaces still occur with great frequency, causing significant morbidity and mortality. At least part of this elevated risk is attributable to the neonatal immune system that tends to favor T regulatory and Th2 type responses when microbes are first encountered. Early-life infection with respiratory viruses is of particular interest because such exposures can disrupt normal lung development and increase the risk of chronic respiratory conditions, such as asthma. The immunologic mechanisms that underlie neonatal host-virus interactions that contribute to the subsequent development of asthma have not yet been fully defined. The goals of this review are (1) to outline the differences between the neonatal and adult immune systems and (2) to present murine and human data that support the hypothesis that early-life interactions between the immune system and respiratory viruses can create a lung environment conducive to the development of asthma.

Propagation of respiratory viruses in human airway epithelia reveals persistent virus-specific signatures

Background

The leading cause of acute illnesses, respiratory viruses, typically cause self-limited diseases, although severe complications can occur in fragile patients. Rhinoviruses (RVs), respiratory enteroviruses (EVs), influenza virus, respiratory syncytial viruses (RSVs), and coronaviruses are highly prevalent respiratory pathogens, but because of the lack of reliable animal models, their differential pathogenesis remains poorly characterized.

Objective

We sought to compare infections by respiratory viruses isolated from clinical specimens using reconstituted human airway epithelia.

Methods

Tissues were infected with RV-A55, RV-A49, RV-B48, RV-C8, and RV-C15; respiratory EV-D68; influenza virus H3N2; RSV-B; and human coronavirus (HCoV)–OC43. Replication kinetics, cell tropism, effect on tissue integrity, and cytokine secretion were compared. Viral adaptation and tissue response were assessed through RNA sequencing.

Results

RVs, RSV-B, and HCoV-OC43 infected ciliated cells and caused no major cell death, whereas H3N2 and EV-D68 induced ciliated cell loss and tissue integrity disruption. H3N2 was also detected in rare goblet and basal cells. All viruses, except RV-B48 and HCoV-OC43, altered cilia beating and mucociliary clearance. H3N2 was the strongest cytokine inducer, and HCoV-OC43 was the weakest. Persistent infection was observed in all cases. RNA sequencing highlighted perturbation of tissue metabolism and induction of a transient but important immune response at 4 days after infection. No majority mutations emerged in the viral population.

Conclusion

Our results highlight the differential in vitro pathogenesis of respiratory viruses during the acute infection phase and their ability to persist under immune tolerance. These data help to appreciate the range of disease severity observed in vivo and the occurrence of chronic respiratory tract infections in immunocompromised hosts.

A multiplex liquid-chip assay based on Luminex xMAP technology for simultaneous detection of six common respiratory viruses

We utilized one-step multiplex reverse transcription-PCR (RT-PCR) and Luminex xMAP technology to develop a respiratory multiplex liquid-chip assay (rMLA) for simultaneous detection of 6 common respiratory viruses, including influenza virus type A (FluA) and type B (FluB), para-influenza virus type 3 (PIV-3), respiratory syncytial virus (RSV), human metapneumovirus (MPV) and a threatening virus to China, Middle East Respiratory Syndrome coronavirus (MERS-CoV). Performance of rMLA was evaluated by comparing with real-time RT-PCR. Detection data from clinical specimens showed that the rMLA had diagnostic sensitivities of 97.10% for FluA, 94.59% for FluB, 98.68% for PIV-3, 94.87% for RSV and 95.92% for MPV (No Data for MERS-CoV due to the lack of positive specimens). Data of analytical sensitivities showed that the detection limits of the rMLA assay were 5–25 viral RNA copies per μl for FluA, FluB, PIV-3 and MERS-CoV, approximate to the real-time RT-PCR assay; while the values were 8 and 22copies/μl for MPV and RSV, lower than the real-time RT-PCR(78 and 114 copies/μl respectively). The results indicated that the rMLA is a sensitive, specific detection tool and comparable to real-time RT-PCR, especially suitable for high-throughput detection of respiratory specimens.

Understanding the Association of Human Rhinovirus with Asthma

Human rhinoviruses are ubiquitous seasonal pathogens. They have known associations with first onset of wheezing illnesses in children and with asthma exacerbations in patients of all ages. It is not yet certain whether human rhinoviruses play a direct role in the pathogenesis of asthma by activating deleterious inflammatory responses or if they only serve as a catalyst to accelerate the disease in genetically predisposed individuals. There have been previously demonstrated reductions in the development of the asthmatic phenotype with passive immunization against respiratory syncytial virus; however, in the case of rhinovirus, there are barriers to effective vaccine development, such as the lack of a common antigenic target due to alterations of surface markers among subtypes. It remains to be determined whether certain subtypes of human rhinovirus are more asthmagenic and therefore worthy of greater attention as vaccine candidates, but several studies have suggested that RV-C and certain RV-A strains may be more strongly linked with asthma.

Hospitalizations and outpatient visits for rhinovirus-associated acute respiratory illness in adults

BACKGROUND

Rhinovirus is linked to asthma exacerbations and chronic obstructive pulmonary disease exacerbations in adults. The severity and rates of rhinovirus acute respiratory illnesses (ARIs) in adults are uncertain.

OBJECTIVES

We sought to determine rhinovirus-associated ARI rates in adults presenting for care in multiple settings and identify factors associated with rhinovirus detection.

METHODS

This prospective, population-based cohort enrolled Tennessee residents 18 years or older in the emergency department (ED), outpatient clinics, or hospitalized for ARI from December 2008 to May 2010. Nasal/throat swabs were collected and tested for rhinovirus and other viruses by using RT-PCR. Rates of ED visits and hospitalizations were calculated and rhinovirus-positive and rhinovirus-negative patients were compared.

RESULTS

Among 2351 enrollees, rhinovirus was detected in 247 (11%). There were 7 rhinovirus-associated ED visits and 3 hospitalizations per 1000 adults annually. Patients with rhinovirus, compared with virus-negative ARI, were more likely to present with wheezing (odds ratio [OR], 1.7; 95% CI, 1.23-2.35; P < .001), to be a current smoker (OR, 2.31; 95% CI, 1.68-3.19) or live with a smoker (OR, 1.72; 95% CI, 1.10-2.67), have a history of chronic respiratory disease (OR, 1.61; 95% CI, 1.17-2.22), and were less likely to be hospitalized versus seen in the outpatient setting (OR, 0.58; 95% CI, 0.41-0.83).

CONCLUSIONS

Rhinovirus is associated with a substantial number of ED visits and hospitalizations for ARIs in adults. There may be modifiable factors that can reduce the likelihood of presenting with rhinovirus-associated ARIs.

Human rhinovirus infections in hospitalized children: clinical, epidemiological and virological features

Molecular epidemiology and clinical impact of human rhinovirus (HRV) are not well documented in tropical regions. This study compared the clinical characteristics of HRV to other common viral infections and investigated the molecular epidemiology of HRV in hospitalized children with acute respiratory infections (ARIs) in Vietnam. From April 2010 to May 2011, 1082 nasopharyngeal swabs were screened for respiratory viruses by PCR. VP4/VP2 sequences of HRV were further characterized. HRV was the most commonly detected virus (30%), in which 70% were diagnosed as either pneumonia or bronchiolitis. Children with single HRV infections presented with significantly higher rate of hypoxia than those infected with respiratory syncytial virus or parainfluenza virus (PIV)-3 (12·4% vs. 3·8% and 0%, respectively, P < 0·05), higher rate of chest retraction than PIV-1 (57·3% vs. 34·5%, P = 0·028), higher rate of wheezing than influenza A (63·2% vs. 42·3%, P = 0·038). HRV-C did not differ to HRV-A clinically. The genetic diversity and changes of types over time were observed and may explain the year-round circulation of HRV. One novel HRV-A type was discovered which circulated locally for several years. In conclusion, HRV showed high genetic diversity and was associated with significant morbidity and severe ARIs in hospitalized children.

Antibiotics for acute laryngitis in adults

BACKGROUND

This is an update of the original review published in 2005. Acute laryngitis is a common illness worldwide. Diagnosis is often made by case history alone and treatment often targets symptoms.

OBJECTIVES

To assess the effectiveness and safety of different antibiotic therapies in adults with acute laryngitis. A secondary objective was to report the rates of adverse events associated with these treatments.

SEARCH METHODS

We searched CENTRAL (2014, Issue 11), MEDLINE (January 1966 to November week 3, 2014), EMBASE (1974 to December 2014), LILACS (1982 to December 2014) and BIOSIS (1980 to December 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing any antibiotic therapy with placebo for acute laryngitis. The main outcome was objective voice scores.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted and synthesised data.

MAIN RESULTS

We included three RCTs (351 participants) that had moderate to high risk of bias. The quality of the evidence was very low for all outcomes. We downgraded the studies because of limitations in study design or execution (risk of bias), imprecision and inconsistency of results. We included a new trial presented only as a conference abstract in this update.In one study of acute laryngitis in adults, 100 participants were randomised to receive penicillin V (800 mg twice daily for five days) or an identical placebo. A recording of each patient reading a standardised text was made at the first visit, during re-examination after one and two weeks, and at follow-up after two to six months. No significant differences were found between the groups. The trial also measured symptoms reported by participants and found no significant differences.One study investigated erythromycin for acute laryngitis in 106 adults. The mean objective voice scores measured at the first visit, at re-examination after one and two weeks, and at follow-up after two to six months did not significantly differ between the groups. At one week there were significant beneficial differences in the severity of reported vocal symptoms (slight, moderate and severe) as judged by participants (P value = 0.042). However, the rates of participants having improved voice disturbance (subjective symptoms) at one and two weeks were not significantly different among groups. Comparing erythromycin and placebo groups on the rate of persistence of cough at two weeks, the risk ratio (RR) was 0.38 (95% confidence interval (CI) 0.15 to 0.97, P value = 0.04) and the number needed to treat for an additional beneficial outcome (NNTB) was 5.87 (95% CI 3.09 to 65.55). We calculated a RR of 0.64 (95% CI 0.46 to 0.90, P value = 0.034) and a NNTB of 3.76 (95% CI 2.27 to 13.52; P value = 0.01) for the subjective voice scores at one week.A third trial from Russia included 145 patients with acute laryngitis symptoms. Participants were randomised to three treatment groups: Group 1: seven-day course of fusafungine (six times a day by inhalation); Group 2: seven-day course of fusafungine (six times a day by inhalation) plus clarithromycin (250 mg twice daily for seven days); Group 3: no treatment. Clinical cure rates were measured at days 5 ± 1, 8 ± 1 and 28 ± 2. The authors reported significant differences in the rates of clinical cure at day 5 ± 1 favouring fusafungine (one trial; 93 participants; RR 1.50, 95% CI 1.02 to 2.20; P value = 0.04) and fusafungine plus clarithromycin (one trial 97 participants; RR 1.47, 95% CI 1.00 to 2.16; P value = 0.05) when compared to no treatment. However, no significant differences were found at days 8 ± 1 and 28 ± 2. Also, no significant differences were found when comparing fusafungine to fusafungine plus clarithromycin at days 5 ± 1, 8 ± 1 and 28 ± 2.

AUTHORS' CONCLUSIONS

Antibiotics do not appear to be effective in treating acute laryngitis when assessing objective outcomes. They appear to be beneficial for some subjective outcomes. Erythromycin could reduce voice disturbance at one week and cough at two weeks when measured subjectively. Fusafungine could increase the cure rate at day five. The included RCTs had important methodological problems and these modest benefits from antibiotics may not outweigh their cost, adverse effects or negative consequences for antibiotic resistance patterns.

Carrageenan nasal spray in virus confirmed common cold: individual patient data analysis of two randomized controlled trials

Background

Clinical trials applying iota-carrageenan nasal spray have previously shown to reduce duration of virus-confirmed common cold. The present study pooled data of two similar clinical trials to provide further evidence for the antiviral effectiveness of carrageenan.

Methods

Individual patient data were analyzed from two randomized double blind placebo controlled trials assessing the therapeutic effectiveness of carrageenan nasal spray in acute common cold. Patients with virus-confirmed common cold (n = 254, verum 126, placebo 128) were included and the following parameters were appraised: duration of disease, number of patients with relapses, number of respiratory viruses and viral titers at inclusion (visit 1) compared to days 3–5 (visit 2).

Results

Carrageenan treated patients showed a significant reduction in duration of disease of almost 2 days (p < 0.05) as well as significantly fewer relapses during 21 days of observation period (p < 0.05). The virus clearance between visit 1 and visit 2 was significantly more pronounced in the carrageenan group (p < 0.05). In both studies, virus-confirmed common cold was caused by three main virus subtypes: human rhinovirus (46%), human coronavirus (25%) and influenza A (14%) virus. Carrageenan nasal spray showed significant antiviral efficacy in all three virus subgroups, the highest effectiveness was observed in human corona virus-infected patients. The reduced duration of disease was 3 days (p < 0.01) and the number of relapses was three times less (p < 0.01) in carrageenan treated corona-virus-infected patients compared to control patients.

Conclusions

Administration of carrageenan nasal spray in children as well as in adults suffering from virus-confirmed common cold reduced duration of disease, increased viral clearance and reduced relapses of symptoms. Carrageenan nasal spray appeared as an effective treatment of common cold in children and adults.

Trial registration

Pooled data from ISRCTN52519535 and ISRCTN80148028

IL-15 complexes induce NK- and T-cell responses independent of type I IFN signaling during rhinovirus infection

Rhinoviruses are among the most common viruses to infect man, causing a range of serious respiratory diseases including exacerbations of asthma and COPD. Type I IFN and IL-15 are thought to be required for antiviral immunity; however, their function during rhinovirus infection in vivo is undefined. In RV-infected human volunteers, IL-15 protein expression in fluid from the nasal mucosa and in bronchial biopsies was increased. In mice, RV induced type I IFN-dependent expressions of IL-15 and IL-15Rα, which in turn were required for NK- and CD8(+) T-cell responses. Treatment with IL-15-IL-15Rα complexes (IL-15c) boosted RV-induced expression of IL-15, IL-15Rα, IFN-γ, CXCL9, and CXCL10 followed by recruitment of activated, IFN-γ-expressing NK, CD8(+), and CD4(+) T cells. Treating infected IFNAR1(-/-) mice with IL-15c similarly increased IL-15, IL-15Rα, IFN-γ, and CXCL9 (but not CXCL10) expression also followed by NK-, CD8(+)-, and CD4(+)-T-cell recruitment and activation. We have demonstrated that type I IFN-induced IFN-γ and cellular immunity to RV was mediated by IL-15 and IL-15Rα. Importantly, we also show that IL-15 could be induced via a type I IFN-independent mechanism by IL-15 complex treatment, which in turn was sufficient to drive IFN-γ expression and lymphocyte responses.

New small-molecule inhibitors effectively blocking picornavirus replication

Few drugs targeting picornaviruses are available, making the discovery of antivirals a high priority. Here, we identified and characterized three compounds from a library of kinase inhibitors that block replication of poliovirus, coxsackievirus B3, and encephalomyocarditis virus. Using an in vitro translation-replication system, we showed that these drugs inhibit different stages of the poliovirus life cycle. A4(1) inhibited both the formation and functioning of the replication complexes, while E5(1) and E7(2) were most effective during the formation but not the functioning step. Neither of the compounds significantly inhibited VPg uridylylation. Poliovirus resistant to E7(2) had a G5318A mutation in the 3A protein. This mutation was previously found to confer resistance to enviroxime-like compounds, which target a phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ)-dependent step in viral replication. Analysis of host protein recruitment showed that E7(2) reduced the amount of GBF1 on the replication complexes; however, the level of PI4KIIIβ remained intact. E7(2) as well as another enviroxime-like compound, GW5074, interfered with viral polyprotein processing affecting both 3C- and 2A-dependent cleavages, and the resistant G5318A mutation partially rescued this defect. Moreover, E7(2) induced abnormal recruitment to membranes of the viral proteins; thus, enviroxime-like compounds likely severely compromise the interaction of the viral polyprotein with membranes. A4(1) demonstrated partial protection from paralysis in a murine model of poliomyelitis. Multiple attempts to isolate resistant mutants in the presence of A4(1) or E5(1) were unsuccessful, showing that effective broad-spectrum antivirals could be developed on the basis of these compounds.

IMPORTANCE

Diverse picornaviruses can trigger multiple human maladies, yet currently, only hepatitis A virus and poliovirus can be controlled with vaccination. The development of antipicornavirus therapeutics is also facing significant difficulties because these viruses readily generate resistance to compounds targeting either viral or cellular factors. Here, we describe three novel compounds that effectively block replication of distantly related picornaviruses with minimal toxicity to cells. The compounds prevent viral RNA replication after the synthesis of the uridylylated VPg primer. Importantly, two of the inhibitors are strongly refractory to the emergence of resistant mutants, making them promising candidates for further broad-spectrum therapeutic development. Evaluation of one of the compounds in an in vivo model of poliomyelitis demonstrated partial protection from the onset of paralysis.

Population structure and evolution of Rhinoviruses

Rhinoviruses, formerly known as Human rhinoviruses, are the most common cause of air-borne upper respiratory tract infections in humans. Rhinoviruses belong to the family Picornaviridae and are divided into three species namely, Rhinovirus A, -B and -C, which are antigenically diverse. Genetic recombination is found to be one of the important causes for diversification of Rhinovirus species. Although emerging lineages within Rhinoviruses have been reported, their population structure has not been studied yet. The availability of complete genome sequences facilitates study of population structure, genetic diversity and underlying evolutionary forces, such as mutation, recombination and selection pressure. Analysis of complete genomes of Rhinoviruses using a model-based population genetics approach provided a strong evidence for existence of seven genetically distinct subpopulations. As a result of diversification, Rhinovirus A and -C populations are divided into four and two subpopulations, respectively. Genetically, the Rhinovirus B population was found to be homogeneous. Intra-species recombination was observed to be prominent in Rhinovirus A and -C species. Significant evidence of episodic positive selection was obtained for several sites within coding sequences of structural and non-structural proteins. This corroborates well with known phenotypic properties such as antigenicity of structural proteins. Episodic positive selection appears to be responsible for emergence of new lineages especially in Rhinovirus A. In summary, the Rhinovirus population is an ensemble of seven distinct lineages. In case of Rhinovirus A, intra-species recombination and episodic positive selection contribute to its further diversification. In case of Rhinovirus C, intra- and inter-species recombinations are responsible for observed diversity. Population genetics approach was further useful to analyze phylogenetic tree topologies pertaining to recombinant strains, especially when trees are derived using complete genomes. Understanding of population structure serves as a foundation for designing new vaccines and drugs as well as to explain emergence of drug resistance amongst subpopulations.

Efficacy of a carrageenan nasal spray in patients with common cold: a randomized controlled trial

Background

The common cold is the most widespread viral infection in humans. Iota-carrageenan has previously shown antiviral effectiveness against cold viruses in clinical trials. This study investigated the efficacy of a carrageenan-containing nasal spray on the duration of the common cold and nasal fluid viral load in adult patients.

Methods

In a randomized, double-blind, placebo-controlled trial, 211 patients suffering from early symptoms of the common cold were treated for seven days. Application was performed three times daily with either a carrageenan-supplemented nasal spray or saline solution as placebo with an overall observation period of 21 days. The primary endpoint was the duration of disease defined as the time until the last day with symptoms followed by all other days in the study period without symptoms. During the study, but prior unblinding, the definition of disease duration was adapted from the original protocol that defines disease duration as the time period of symptoms followed by 48 hours without symptoms.

Results

In patients showing a laboratory-confirmed cold virus infection and adherence to the protocol, alleviation of symptoms was 2.1 days faster in the carrageenan group in comparison to placebo (p = 0.037). The primary endpoint that had been prespecified but was changed before unblinding was not met. Viral titers in nasal fluids showed a significantly greater decrease in carrageenan patients in the intention-to-treat population (p = 0.024) and in the per protocol population (p = 0.018) between days 1 and 3/4.

Conclusions

In adults with common cold virus infections, direct local administration of carrageenan with nasal sprays reduced the duration of cold symptoms. A significant reduction of viral load in the nasal wash fluids of patients confirmed similar findings from earlier trials in children and adults.

Trial registration

Current Controlled Trials ISRCTN80148028

Detection of viral and bacterial pathogens in acute respiratory infections

OBJECTIVES

The role of bacteria in acute respiratory illnesses (ARI) of adults and interactions with viral infections is incompletely understood. This study tested the hypothesis that bacterial co-infection during ARI adds to airway inflammation and illness severity.

METHODS

Two groups of 97 specimens each were randomly selected from multiplex-PCR identified virus-positive and virus-negative nasal specimens obtained from adults with new onset ARI, and 40 control specimens were collected from healthy adults. All specimens were analyzed for Haemophilus influenzae(HI), Moraxella catarrhalis(MC) and Streptococcus pneumoniae(SP) by quantitative-PCR. General linear models tested for relationships between respiratory pathogens, biomarkers (nasal wash neutrophils and CXCL8), and ARI-severity.

RESULTS

Nasal specimens from adults with ARIs were more likely to contain bacteria (37% overall; HI = 28%, MC = 14%, SP = 7%) compared to specimens from healthy adults (5% overall; HI = 0%, MC = 2.5%, SP = 2.5%; p < 0.001). Among ARI specimens, bacteria were more likely to be detected among virus-negative specimens compared to virus-positive specimens (46% vs. 27%; p = 0.0046). The presence of bacteria was significantly associated with increased CXCL8 and neutrophils, but not increased symptoms.

CONCLUSION

Pathogenic bacteria were more often detected in virus-negative ARI, and also associated with increased inflammatory biomarkers. These findings suggest the possibility that bacteria may augment virus-induced ARI and contribute to airway inflammation.

Antibiotics for acute laryngitis in adults

BACKGROUND

This is an updated version of the original review published in Issue 2, 2007 of The Cochrane Library. Acute laryngitis is a common illness worldwide. Diagnosis is often made by case history alone and treatment is often directed toward controlling symptoms.

OBJECTIVES

To assess the effectiveness and safety of different antibiotic therapies in adults with acute laryngitis. A secondary objective was to report the rates of adverse events associated with these treatments.

SEARCH METHODS

We searched CENTRAL 2012, Issue 12, MEDLINE (January 1966 to January week 3, 2013), EMBASE (1974 to January 2013), LILACS (1982 to January 2013) and BIOSIS (1980 to January 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing any antibiotic therapy with placebo for acute laryngitis. The main outcome was objective voice scores.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted and descriptively synthesised data.

MAIN RESULTS

Only two trials met the study inclusion criteria after extensive literature searches. One hundred participants were randomised to receive either penicillin V (800 mg twice a day for five days), or an identical placebo, in a study of acute laryngitis in adults. A tape recording of each patient reading a standardised text was obtained during the first visit, subsequently during re-examination after one and two weeks, and at follow-up after two to six months. No significant differences were found between the groups. The trial also measured symptoms reported by participants and found no significant differences.The second trial investigated erythromycin for treating acute laryngitis in 106 adults. The mean objective voice scores measured at the first visit, at re-examination after one and two weeks, and at follow-up after two to six months did not significantly differ between control and intervention groups. At one week there were significant beneficial differences in the severity of reported vocal symptoms as judged by the participants (P = 0.042). Comparing the erythromycin and placebo groups on subjective voice scores, the a priori risk ratio (RR) was 0.7 (95% confidence interval (CI) 0.51 to 0.96, P = 0.034) and the number needed to treat for an additional beneficial outcome (NNTB) was 4.5.

AUTHORS' CONCLUSIONS

Antibiotics appear to have no benefit in treating acute laryngitis. Erythromycin could reduce voice disturbance at one week and cough at two weeks when measured subjectively. We consider that these outcomes are not relevant in clinical practice. The implications for practice are that prescribing antibiotics should not be done in the first instance as they will not objectively improve symptoms.

Rhinovirus infections in western Sweden: a four-year molecular epidemiology study comparing local and globally appearing types

Human rhinovirus (HRV) is a highly prevalent pathogen and a major cause of acute respiratory tract infection (ARTI). HRV express less seasonality than other viral ARTIs, which typically appear as seasonal epidemics lasting for 1–2 months. The aim of this study was to investigate the seasonal patterns of HRV types over four consecutive years in one geographic region. HRV identified in respiratory samples from 114 patients over a four-year period were analysed by VP4/VP2 sequencing. HRV-A was found in 64, HRV-B in 11 and HRV-C in 37 cases. Overall, 33 different HRV-A types, nine B types and 21 C types were found. As many as 21 of the HRV types appeared during several seasons, with a maximum time-span of four years. Some types appeared during successive seasons and, in some cases, phylogenetic analysis indicated extended periods of circulation locally. Most of the strains were closely related to HRV identified in other parts of the world during the same time period. HRV strains that circulate locally represent many types and seem to reflect that HRV infections are highly globalised. The existence of simultaneous or successive epidemics with different HRV types in combination with the ability of each type to remain in the local population over extended periods of time may contribute to explaining the high rate of HRV infections.

George K, Walsh TJ. Human rhinoviruses

Human rhinoviruses (HRVs), first discovered in the 1950s, are responsible for more than one-half of cold-like illnesses and cost billions of dollars annually in medical visits and missed days of work. Advances in molecular methods have enhanced our understanding of the genomic structure of HRV and have led to the characterization of three genetically distinct HRV groups, designated groups A, B, and C, within the genus Enterovirus and the family Picornaviridae. HRVs are traditionally associated with upper respiratory tract infection, otitis media, and sinusitis. In recent years, the increasing implementation of PCR assays for respiratory virus detection in clinical laboratories has facilitated the recognition of HRV as a lower respiratory tract pathogen, particularly in patients with asthma, infants, elderly patients, and immunocompromised hosts. Cultured isolates of HRV remain important for studies of viral characteristics and disease pathogenesis. Indeed, whether the clinical manifestations of HRV are related directly to viral pathogenicity or secondary to the host immune response is the subject of ongoing research. There are currently no approved antiviral therapies for HRVs, and treatment remains primarily supportive. This review provides a comprehensive, up-to-date assessment of the basic virology, pathogenesis, clinical epidemiology, and laboratory features of and treatment and prevention strategies for HRVs.

Advantage of meditation over exercise in reducing cold and flu illness is related to improved function and quality of life

Please cite this paper as: Obasi et al. (2012) Advantage of meditation over exercise in reducing cold and flu illness is related to improved function and quality of life. Influenza and Other Respiratory Viruses 00(0), 00–00.

Purpose  To examine whether apparent advantages following training in meditation over exercise can be attributed to specific symptoms, functional impairments, or quality‐of‐life indicators assessed by the Wisconsin Upper Respiratory Symptom Survey (WURSS‐24).

Methods  Results from the randomized controlled trial “Meditation or Exercise for Preventing Acute Respiratory Illness” showed mean global severity and total days of illness were worse in control (358, 8·9) compared with exercise (248, 5·1) or meditation (144, 5·0). Global severity of illness was estimated using area under the curve from daily self‐reported severity scores on the WURSS‐24. For this project, we estimated within‐group WURSS item‐level severity and between‐group effect sizes (Cohen’s “d” statistic) relative to control. The item‐level effect sizes were grouped into (i) symptom and (ii) function and quality of life domains.

Results  Among the three groups, mediators showed the lowest severity estimates for 21 of 22 WURSS items. Item‐level Cohen’s “d” indicated most benefit was evident in WURSS items representing function and quality of life. Compared with exercise, meditation fostered larger reductions in illness severity, although due mostly to improved function and the quality of life domain (d = −0·33, P < 0·001) compared with symptom domain (d = −0·22, P < 0·001).

Conclusions  The apparent advantage of training in meditation over exercise for reducing cold and flu illness is explained more by improved function and quality of life than by a reduction in symptom severity.

Human rhinoviruses in severe respiratory disease in very low birth weight infants

OBJECTIVES

To assess incidence, burden of illness, and risk factors for human rhinoviruses (HRVs) in a cohort of very low birth weight (VLBW) infants.

METHODS

A 2-year prospective cohort study was conducted among VLBW premature infants in Buenos Aires, Argentina. Infants were enrolled in the NICU from June 1, 2003, to May 31, 2005, and managed monthly and with every acute respiratory illness (ARI) during the first year of life. Nasal wash samples were obtained during every respiratory episode and tested for HRV, respiratory syncytial virus (RSV), human parainfluenza viruses, influenza viruses, and human metapneumovirus using reverse transcriptase-polymerase chain reaction.

RESULTS

Of 119 patients, 66 (55%) had HRV-associated ARIs. The incidence of HRV-associated ARI was 123 events per 100 child-years of follow-up. Of those infants experiencing an episode of bronchiolitis, 40% had HRV versus 7% with RSV. The incidence of HRV-associated bronchiolitis was 75 per 100 infant-years of follow-up. HRV was associated with 12 of 36 hospitalizations (33%), and RSV was associated with 9 of 36 hospitalizations (25%). The incidence of HRV-associated hospitalization was 12 per 100 infant-years of follow-up. The risk of HRV-associated hospitalization was higher for infants with bronchopulmonary dysplasia and those who were not breastfed.

CONCLUSIONS

HRV is an important and frequent pathogen associated with severe respiratory infections in VLBW infants. Bronchopulmonary dysplasia and the absence of breastfeeding are risk factors for hospitalization. The results of our study reveal that HRV is the predominant pathogen of respiratory infections in premature infants.

In China, students in crowded dormitories with a low ventilation rate have more common colds: evidence for airborne transmission

Objective

To test whether the incidence of common colds among college students in China is associated with ventilation rates and crowdedness in dormitories.

Methods

In Phase I of the study, a cross-sectional study, 3712 students living in 1569 dorm rooms in 13 buildings responded to a questionnaire about incidence and duration of common colds in the previous 12 months. In Phase II, air temperature, relative humidity and CO₂ concentration were measured for 24 hours in 238 dorm rooms in 13 buildings, during both summer and winter. Out-to indoor air flow rates at night were calculated based on measured CO₂ concentrations.

Results

In Phase I, 10% of college students reported an incidence of more than 6 common colds in the previous 12 months, and 15% reported that each infection usually lasted for more than 2 weeks. Students in 6-person dorm rooms were about 2 times as likely to have an incidence of common colds ≥6 times per year and a duration ≥2 weeks, compared to students in 3-person rooms. In Phase II, 90% of the measured dorm rooms had an out-to indoor air flow rate less than the Chinese standard of 8.3 L/s per person during the heating season. There was a dose-response relationship between out-to indoor air flow rate per person in dorm rooms and the proportion of occupants with annual common cold infections ≥6 times. A mean ventilation rate of 5 L/(s•person) in dorm buildings was associated with 5% of self reported common cold ≥6 times, compared to 35% at 1 L/(s•person).

Conclusion

Crowded dormitories with low out-to indoor airflow rates are associated with more respiratory infections among college students.

New human rhinovirus species and their significance in asthma exacerbation and airway remodeling

Asthma is the most common chronic disease of childhood, affecting 10% to 15% of all children. Several different stimuli including allergens, tobacco smoke, certain drugs, and viral or bacterial infections are known to exacerbate asthma symptoms. Among these triggers, viruses are frequent inducers of asthma exacerbations, with human rhinoviruses being the most common in children and adults. This article describes the different species of this virus and their roles as major triggers of asthma exacerbations.

Newly identified human rhinoviruses: molecular methods heat up the cold viruses

Human rhinovirus (HRV) infections cause at least 70% of virus‐related wheezing exacerbations and cold and flu‐like illnesses. They are associated with otitis media, sinusitis and pneumonia. Annually, the economic impact of HRV infections costs billions in healthcare and lost productivity. Since 1987, 100 officially recognised HRV serotypes reside in two genetically distinct species; HRV A and HRV B, within the genus Enterovirus, family Picornaviridae. Sequencing of their ∼7kb genomes was finalised in 2009. Since 1999, many globally circulating, molecularly‐defined ‘strains’, perhaps equivalent to novel serotypes, have been discovered but remain uncharacterised. Many of these currently unculturable strains have been assigned to a proposed new species, HRV C although confusion exists over the membership of the species. There has not been sufficient sampling to ensure the identification of all strains and no consensus criteria exist to define whether clinical HRV detections are best described as a distinct strain or a closely related variant of a previously identified strain (or serotype). We cannot yet robustly identify patterns in the circulation of newly identified HRVs (niHRVs) or the full range of associated illnesses and more data are required. Many questions arise from this new found diversity: what drives the development of so many distinct viruses compared to other species of RNA viruses? What role does recombination play in generating this diversity? Are there species‐ or strain‐specific circulation patterns and clinical outcomes? Are divergent strains sensitive to existing capsid‐binding antivirals? This update reviews the findings that trigger these and other questions arising during the current cycle of intense rhinovirus discovery. Copyright © 2010 John Wiley & Sons, Ltd.

Do rhinoviruses reduce the probability of viral co-detection during acute respiratory tract infections?

BACKGROUND

Human rhinoviruses (HRVs) are often concurrently detected with other viruses found in the respiratory tract because of the high total number of HRV infections occurring throughout the year. This feature has previously relegated HRVs to being considered passengers in acute respiratory infections. HRVs remain poorly characterized and are seldom included as a target in diagnostic panels despite their pathogenic potential, infection-associated healthcare expenditure and relatively unmoderated elicitation of an antiviral state.

OBJECTIVES

To test the hypothesis that respiratory viruses are proportionately more or less likely to co-occur, particularly the HRVs.

STUDY DESIGN

Retrospective PCR-based analyses of 1247 specimens for 17 viruses, including HRV strains, identified 131 specimens containing two or more targets. We investigated the proportions of co-detections and compared the proportion of upper vs. lower respiratory tract presentations in the HRV positive group. Both univariate contingency table and multivariate logistic regression analyses were conducted to identify trends of association among the viruses present in co-detections.

RESULTS

Many of the co-detections occurred in patterns. In particular, HRV detection was associated with a reduced probability of detecting human adenoviruses, coronaviruses, bocavirus, metapneumovirus, respiratory syncytial virus, parainfluenza virus, influenza A virus, and the polyomaviruses KIPyV and WUPyV (p < or = 0.05). No single HRV species nor cluster of particular strains predominated.

CONCLUSIONS

HRVs were proportionately under-represented among viral co-detections. For some period, HRVs may render the host less likely to be infected by other viruses.