Role of respiratory syncytial virus in acute otitis media: implications for vaccine development

Prescribing for different antibiotic classes across age groups in the Kaiser Permanente Northern California population in association with influenza incidence, 2010-2018

There is limited information on the volume of antibiotic prescribing that is influenza-associated, resulting from influenza infections and their complications (such as streptococcal pharyngitis). We estimated that for the Kaiser Permanente Northern California population during 2010-2018, 3.4% (2.8%-4%) of all macrolide prescriptions (fills), 2.7% (2.3%-3.2%) of all aminopenicillin prescriptions, 3.1% (2.4%-3.9%) of all 3rd generation cephalosporins prescriptions, 2.2% (1.8%-2.6%) of all protected aminopenicillin prescriptions and 1.3% (1%-1.6%) of all quinolone prescriptions were influenza-associated. The corresponding proportions were higher for select age groups, e.g. 4.3% of macrolide prescribing in ages over 50 years, 5.1% (3.3%-6.8%) of aminopenicillin prescribing in ages 5-17 years and 3.3% (1.9%-4.6%) in ages <5 years was influenza-associated. The relative contribution of influenza to antibiotic prescribing for respiratory diagnoses without a bacterial indication in ages over 5 years was higher than the corresponding relative contribution to prescribing for all diagnoses. Our results suggest a modest benefit of increasing influenza vaccination coverage for reducing prescribing for the five studied antibiotic classes, particularly for macrolides in ages over 50 years and aminopenicillins in ages <18 years, and the potential benefit of other measures to reduce unnecessary antibiotic prescribing for respiratory diagnoses with no bacterial indication, both of which may contribute to the mitigation of antimicrobial resistance.

Predominant Bacterial and Viral Otopathogens Identified Within the Respiratory Tract and Middle Ear of Urban Australian Children Experiencing Otitis Media Are Diversely Distributed

Background

Otitis media (OM) is one of the most common infections in young children, arising from bacterial and/or viral infection of the middle ear. Globally, Streptococcus pneumoniae and non-typeable Haemophilus influenzae (NTHi) are the predominant bacterial otopathogens. Importantly, common upper respiratory viruses are increasingly recognized contributors to the polymicrobial pathogenesis of OM. This study aimed to identify predominant bacteria and viruses in the nasopharynx, adenoids and middle ears of peri-urban/urban South-East Queensland Australian children, with and without clinical history of chronic otitis media with effusion (COME) and/or recurrent acute otitis media (RAOM).

Methods

Sixty children, 43 diagnosed with OM and 17 controls with no clinical history of OM from peri-urban/urban South-East Queensland community were recruited to the study. Respiratory tract bacterial and viral presence were examined within nasopharyngeal swabs (NPS), middle ear effusions (MEE) and adenoids, using real-time polymerase chain reaction (RT-PCR) and bacterial culture.

Results

At least one otopathogen present was observed in all adenoid samples, 86.1% and 82.4% of NPS for children with and without OM, respectively, and 47.1% of the MEE from the children with OM. NTHi was the most commonly detected bacteria in both the OM and control cohorts within the adenoids (90.0% vs 93.8%), nasopharynx (67.4% vs 58.8%) respectively, and in the MEE (OM cohort 25.9%). Viruses were detected in all adenoid samples, 67.4% vs 47.1% of the NPS from the OM and control cohorts, respectively, and 37% of the MEE. Rhinovirus was the predominant virus identified in the adenoids (85.0% vs 68.8%) and nasopharynx (37.2% vs 41.2%) from the OM and control cohorts, respectively, and the MEE (19.8%).

Conclusions

NTHi and rhinovirus are predominant otopathogens within the upper respiratory tract of children with and without OM from peri-urban and urban South-East Queensland, Australia. The presence of bacterial otopathogens within the middle ear is more predictive of concurrent URT infection than was observed for viruses, and the high otopathogen carriage within adenoid tissues confirms the complex polymicrobial environment in children, regardless of OM history.

Antibiotic prescribing across age groups in the Kaiser Permanente Northern California population in association with different diagnoses, and with influenza incidence, 2010-2018

There is limited information on the volume of antibiotic prescribing that is influenza-associated, resulting from influenza infections and their complications (such as streptococcal pharyngitis and otitis media). Here, we estimated age/diagnosis-specific proportions of antibiotic prescriptions (fills) for the Kaiser Permanente Northern California population during 2010-2018 that were influenza-associated. The proportion of influenza-associated antibiotic prescribing among all antibiotic prescribing was higher in children aged 5-17 years compared to children aged under 5 years, ranging from 1.4% [95% CI (0.7-2.1)] in aged <1 year to 2.7% (1.9-3.4) in aged 15-17 years. For adults aged over 20 years, the proportion of influenza-associated antibiotic prescribing among all antibiotic prescribing was lower, ranging from 0.7% (0.5-1) for aged 25-29 years to 1.6% (1.2-1.9) for aged 60-64 years. Most of the influenza-associated antibiotic prescribing in children aged under 10 years was for ear infections, while for age groups over 25 years, 45-84% of influenza-associated antibiotic prescribing was for respiratory diagnoses without a bacterial indication. This suggests a modest benefit of increasing influenza vaccination coverage for reducing antibiotic prescribing, as well as the potential benefit of other measures to reduce unnecessary antibiotic prescribing for respiratory diagnoses with no bacterial indication in persons aged over 25 years, both of which may further contribute to the mitigation of antimicrobial resistance.

Respiratory viruses in the healthy middle ear and middle ear with otitis media with effusion

To investigate the presence of respiratory viruses in the middle ear cavity of the individuals with a healthy middle ear and the children with otitis media with effusion (OME). A total of 72 middle ear samples were collected from 25 children with OME (Group 1) and 47 individuals with no middle ear disease (Group 2). Multiplex real-time polymerase chain reaction was used to investigate the presence of 20 different respiratory viruses. Virus results were compared with bacteriomes of the same populations. At least one respiratory virus was detected in 56% of the patients in Group 1 and 12.8% of the individuals in Group 2. The viral co-infection rate for Group 1 and 2 was 8% and 2.1%, respectively. In Group 1, adenovirus was the most frequently detected virus with a rate of 24%, either alone (16%) or concurrent with other viruses (8%), followed by influenza B (12%), rhinovirus, and bocavirus (8%) each. Parainfluenza 4, coronavirus OC43, and RSV A/B were detected in 4% of the sample each. In Group 2, rhinovirus was detected in two samples (4.3%) followed by adenovirus, coronavirus OC43, coronavirus E299, and coronavirus NL63 with a rate of 2.1% each. The detection rate of respiratory viruses was significantly higher in children aged 6 to 11 years. There was no positive association between virus and bacteria found in the middle ear cavity. The current study has provided comprehensive data indicating the presence of diverse respiratory viruses in the healthy middle ear cavity. Our results also suggest that respiratory viruses might have a contribution to OME pathogenesis.

Respiratory Syncytial Virus-associated Acute Otitis Media in Infants and Children

Despite recent declines in the incidence of acute otitis media (AOM), more than 5 million cases and 5-6 million primary AOM visits still occur in young children in the United States, resulting in $4.4 billion direct medical costs annually. Our aims in this review are to describe the role of respiratory syncytial virus (RSV) in the etiology of AOM, discuss the prospect of prevention of RSV-associated AOM through immunization, and suggest future research strategies to assess the impact of immunization on RSV-associated AOM.

Translating Recent Microbiome Insights in Otitis Media into Probiotic Strategies

The microbiota of the upper respiratory tract (URT) protects the host from bacterial pathogenic colonization by competing for adherence to epithelial cells and by immune response regulation that includes the activation of antimicrobial and (anti-)inflammatory components. However, environmental or host factors can modify the microbiota to an unstable community that predisposes the host to infection or inflammation. One of the URT diseases most often encountered in children is otitis media (OM). The role of pathogenic bacteria like Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in the pathogenesis of OM is well documented. Results from next-generation-sequencing (NGS) studies reveal other bacterial taxa involved in OM, such as Turicella and Alloiococcus Such studies can also identify bacterial taxa that are potentially protective against URT infections, whose beneficial action needs to be substantiated in relevant experimental models and clinical trials. Of note, lactic acid bacteria (LAB) are members of the URT microbiota and associated with a URT ecosystem that is deemed healthy, based on NGS and some experimental and clinical studies. These observations have formed the basis of this review, in which we describe the current knowledge of the molecular and clinical potential of LAB in the URT, which is currently underexplored in microbiome and probiotic research.

A systematic review and meta-analysis of antimicrobial resistance in paediatric acute otitis media

OBJECTIVE OF REVIEW

Acute otitis media (AOM) is the largest cause of antimicrobial prescriptions amongst children in developed countries. Excessive and inappropriate prescribing is known to drive antimicrobial resistance, but less is known of antimicrobial resistance in AOM-associated bacteria.

TYPE OF REVIEW & SEARCH STRATEGY

We conducted a systematic review and meta-analysis of bacterial prevalence and antimicrobial resistance in studies of paediatric AOM identified from Ovid Medline, Embase and the Cochrane library.

RESULTS

From 48 unique studies, 15,871 samples were included. Only 0.67 (CI 0.63-0.71) of all ear samples grew a bacterial pathogen. The most common bacterial causes of AOM in children were Streptococcus pneumoniae 0.30 (CI 0.27-0.32), Haemophilus influenza 0.23 (CI 0.20-0.26), and Moraxella catarrhalis 0.05 (CI 0.04-0.06). Resistance patterns varied amongst organisms and antimicrobial agents. The pooled proportion of bacterial culture-positive episodes of AOM that could be effectively treated with amoxicillin was 0.85 (CI 0.76-0.94), erythromycin was 0.64 (0.48-0.78) and amoxicillin-clavulanate was 0.95 (CI 0.85-0.98).

CONCLUSION

We have demonstrated the bacteriology and antimicrobial resistance patterns of AOM. Of samples which grew bacteria, on average approximately 15% of isolates demonstrated resistance to amoxicillin; a typical first-line agent. Greater understanding of local bacteriology and resistance patterns is needed to enable improved antimicrobial stewardship.

Otitis Media in Fully Vaccinated Preschool Children in the Pneumococcal Conjugate Vaccine Era

Objectives. To evaluate the effect of pneumococcal conjugate vaccine (PCV13) on the burden of acute otitis media (AOM) and to evaluate the characteristics of AOM versus otitis media with effusion (OME) in the 2 PCV periods. Methods. A cohort of fully vaccinated children aged 18 to 60 months diagnosed with AOM from 2006 to 2015 was identified. Patients with otorrhea/bulging tympanic membrane were considered as true AOM, while those without bulging/otorrhea were considered to have OME. Burden of true AOM in the PCV7 and PCV13 periods and clinical features of true AOM versus OME were compared. Results. Of 393 episodes in our cohort, 50.8% occurred in PCV7 period. Burden of true AOM in the 2 PCV groups was similar: 26% in PCV7 versus 26.4% in PCV13 (odds ratio [OR] = 1.02, 95% confidence interval [CI] = 0.65-1.60). Factors significantly associated with OME were cold season (OR = 1.54, 95% CI = 1.04-2.4), fever (OR = 2.05, 95% CI = 1.29-3.3), and recurrence (OR = 2.24, 95% CI = 1.22-4.09). No complications of AOM were identified. Majority episodes were treated with antibiotics. Conclusion. Unlike the role of PCV13 in reducing invasive pneumococcal disease, its effect on reducing the burden of AOM is minimal as compared with PCV7. With regard to characteristics of AOM versus OME, findings of tympanic membrane should be used to suggest a diagnosis of AOM, instead of occurrence of fever or recurrence of AOM episodes. Using this approach would help in guiding the use of antibiotics appropriately.

Meteorological factors, air pollutants, and emergency department visits for otitis media: a time series study

AbstractOtitis media (OM) is a very common disease in children, which results in a significant economic burden to the healthcare system for hospital-based outpatient departments, emergency departments (EDs), unscheduled medical examinations, and antibiotic prescriptions. The aim of this retrospective observational study is to investigate the association between climate variables, air pollutants, and OM visits observed in the 2007-2010 period at the ED of Cuneo, Italy. Measures of meteorological parameters (temperature, humidity, atmospheric pressure, wind) and outdoor air pollutants (particulate matter, ozone, nitrous dioxide) were analyzed at two statistical stages and in several specific steps (crude and adjusted models) according to Poisson's regression. Response variables included daily examinations for age groups 0-3, 0-6, and 0-18. Control variables included upper respiratory infections (URI), flu (FLU), and several calendar factors. A statistical procedure was implemented to capture any delayed effects. Results show a moderate association for temperature (T), age 0-3, and 0-6 with P < 0.05, as well as nitrous dioxide (NO₂) with P < 0.005 at age 0-18. Results of subsequent models point out to URI as an important control variable. No statistical association was observed for other pollutants and meteorological variables. The dose-response models (DLNM-final stage) implemented separately on a daily and hourly basis point out to an association between temperature (daily model) and RR 1.44 at age 0-3, CI 1.11-1.88 (lag time 0-1 days) and RR 1.43, CI 1.05-1.94 (lag time 0-3 days). The hourly model confirms a specific dose-response effect for T with RR 1.20, CI 1.04-1.38 (lag time range from 0 to 11 to 0-15 h) and for NO₂ with RR 1.03, CI 1.01-1.05 (lag time range from 0 to 8 to 0-15 h). These results support the hypothesis that the clinical context of URI may be an important risk factor in the onset of OM diagnosed at ED level. The study highlights the relevance of URI as a control variable to be included in the statistical analysis in association with meteorological factors and air pollutants. The study also points out to a moderate association of OM with low temperatures and NO₂, with specific risk factors for this variable early in life. Further studies are needed to confirm these findings, particularly with respect to air pollutants in larger urban environments.

Viral Upper Respiratory Tract Infections

The upper respiratory system is one of the most common sites of infection for adults, but even more so for children. Several viruses, from variable families, cause upper respiratory infections which, although generally underestimated due to their typically self-limiting nature, underlie enormous healthcare resource utilization and financial burden. Such, otherwise “benign” infections, can have very significant sequelae both in the form of bringing about local complications but also inducing asthma attacks, thus greatly increasing morbidity. Their enormous prevalence also indicates that rigorous research should be undertaken in order to tackle them, in both the prevention and treatment field.

Modelling estimates of the burden of respiratory syncytial virus infection in children in the UK

OBJECTIVE

The burden of respiratory syncytial virus (RSV) illness is not well characterised in primary care. We estimated the burden of disease attributable to RSV in children in the UK between 1995 and 2009.

DESIGN

Time-series regression modelling.

SETTING

A multiple linear regression model based on weekly viral surveillance (RSV and influenza, Public Health England), and controlled for non-specific seasonal drivers of disease, estimated the proportion of general practitioner (GP) episodes of care (counted as first visit in a series within 28 days; Clinical Practice Research Datalink, CPRD), hospitalisations (Hospital Episode Statistics, HES) and deaths (Office of National Statistics, ONS) attributable to RSV each season.

PARTICIPANTS

Children 0-17 years registered with a GP in CPRD, or with a respiratory disease outcome in the HES or ONS databases.

PRIMARY OUTCOME MEASURES

RSV-attributable burden of GP episodes, hospitalisations and deaths due to respiratory disease by age. RSV-attributable burden associated with selected antibiotic prescriptions.

RESULTS

RSV-attributable respiratory disease in the UK resulted in an estimated 450 158 GP episodes, 29 160 hospitalisations and 83 deaths per average season in children and adolescents, with the highest proportions in children <6 months of age (14 441/100 000 population, 4184/100 000 and 6/100 000, respectively). In an average season, there were an estimated 125 478 GP episodes for otitis media and 416 133 prescriptions for antibiotics attributable to RSV. More GP episodes, hospitalisations and deaths from respiratory disease were attributable to RSV than to influenza in children under 5 years.

CONCLUSIONS

The burden of RSV in children in the UK exceeds that of influenza. RSV in children and adolescents contributes substantially to GP office visits for a diverse range of illnesses, and was associated with an average 416 133 prescribed antibiotic courses per season. Effective antiviral treatments and preventive vaccines are urgently needed for the management of RSV infection in children.

TRIAL REGISTRATION NUMBER

NCT01706302.

Predominant Bacteria Detected from the Middle Ear Fluid of Children Experiencing Otitis Media: A Systematic Review

BACKGROUND

Otitis media (OM) is amongst the most common childhood diseases and is associated with multiple microbial pathogens within the middle ear. Global and temporal monitoring of predominant bacterial pathogens is important to inform new treatment strategies, vaccine development and to monitor the impact of vaccine implementation to improve progress toward global OM prevention.

METHODS

A systematic review of published reports of microbiology of acute otitis media (AOM) and otitis media with effusion (OME) from January, 1970 to August 2014, was performed using PubMed databases.

RESULTS

This review confirmed that Streptococcus pneumoniae and Haemophilus influenzae, remain the predominant bacterial pathogens, with S. pneumoniae the predominant bacterium in the majority reports from AOM patients. In contrast, H. influenzae was the predominant bacterium for patients experiencing chronic OME, recurrent AOM and AOM with treatment failure. This result was consistent, even where improved detection sensitivity from the use of polymerase chain reaction (PCR) rather than bacterial culture was conducted. On average, PCR analyses increased the frequency of detection of S. pneumoniae and H. influenzae 3.2 fold compared to culture, whilst Moraxella catarrhalis was 4.5 times more frequently identified by PCR. Molecular methods can also improve monitoring of regional changes in the serotypes and identification frequency of S. pneumoniae and H. influenzae over time or after vaccine implementation, such as after introduction of the 7-valent pneumococcal conjugate vaccine.

CONCLUSIONS

Globally, S. pneumoniae and H. influenzae remain the predominant otopathogens associated with OM as identified through bacterial culture; however, molecular methods continue to improve the frequency and accuracy of detection of individual serotypes. Ongoing monitoring with appropriate detection methods for OM pathogens can support development of improved vaccines to provide protection from the complex combination of otopathogens within the middle ear, ultimately aiming to reduce the risk of chronic and recurrent OM in vulnerable populations.

Detection of respiratory pathogens in pediatric acute otitis media by PCR and comparison of findings in the middle ear and nasopharynx

We conducted a series of polymerase chain reactions (PCRs) in order to detect bacteria (7 species) and viruses (17 species) in middle ear fluid (MEF) and nasopharynx (Nph) of children with acute otitis media (AOM; n = 179). Bacterial and viral nucleic acids were detected in MEF of 78.8% and 14.5% patients, respectively. The prevalence was as follows: Streptococcus pneumoniae, 70.4%; Haemophilus influenzae, 17.9%; Staphylococcus aureus, 16.8%; Streptococcus pyogenes, 12.3%; Moraxella catarrhalis, 9.5%; rhinovirus, 9.5%; and adenovirus, 3.4%. The overall rate of PCR-positive specimens for bacterial pathogens was 2.6 times higher, compared to culture results. The rate of PCR-positive results and the distribution of pathogens in the Nph were similar to those in the MEF. Nph PCR results had variable positive predictive values and high negative predictive values in predicting MEF findings. Our results indicate that Nph PCR could be a practical tool for examining respiratory pathogens in children with acute infections.

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Middle ear fluid was examined by PCR detecting 24 bacterial/viral species.

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S. pneumoniae prevailed among bacteria and was found in 70.4% patients.

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Among viruses, rhinovirus (9.5%) and adenovirus (3.4%) were the most abandoned.

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Nasopharyngeal PCR results have high predictive value for middle ear fluid findings.

Differential impact of respiratory syncytial virus and parainfluenza virus on the frequency of acute otitis media is explained by lower adaptive and innate immune responses in otitis-prone children

BACKGROUND

Acute otitis media (AOM) is a leading cause of bacterial pediatric infections associated with viral upper respiratory infections (URIs). We examined the differential impact of respiratory syncytial virus (RSV) and parainfluenza virus URIs on the frequency of AOM caused by Streptococcus pneumoniae (Spn) and nontypeable Haemophilus influenzae (NTHi) in stringently defined otitis-prone (sOP) and non-otitis-prone (NOP) children as a potential mechanism to explain increased susceptibility to AOM.

METHODS

Peripheral blood and nasal washes were obtained from sOP and NOP children (n = 309). Colonization events and antiviral responses consisting of total specific immunoglobulin G (IgG) responses, neutralizing antibody responses, and T-cell responses were determined. Isolated neutrophils were infected with varying multiplicities of infection of both viruses, and opsonophagocytosis potential was measured.

RESULTS

A significant increase was found in frequency of AOM events caused by Spn and NTHi, with a concurrent RSV infection in sOP children. These results correlated with diminished total RSV-specific IgG, higher viral nasal burdens, and lower IgG neutralizing capacity. The sOP children had diminished T-cell responses to RSV that correlated with lower Toll-like receptor 3/7 transcript and decreased expression of HLA-DR on antigen-presenting cells. RSV interfered with the Spn phagocytic capacity of neutrophils in a dose-dependent manner. Parainfluenza virus infections did not differentially affect AOM events in sOP and NOP children.

CONCLUSIONS

Lower innate and adaptive immune responses to RSV in sOP children may slow the kinetics of viral clearance from the nasopharynx and allow for viral interference with antibacterial immune responses, thus contributing to increased frequency of AOMs.

Panel 1: Epidemiology, natural history, and risk factors

BACKGROUND

The First International Symposium on Recent Advances in Otitis Media (OM) with Effusion was held in Columbus, Ohio, in 1975. The symposium has been organized in the United States every 4 years since, followed by a research conference to (a) assess major research accomplishments, (b) identify important research questions and opportunities, (c) develop consensus on definitions and terminology, and (d) establish priorities with short- and long-term research goals. One of the principal areas reviewed quadrennially is Epidemiology, Natural History, and Risk Factors.

OBJECTIVE

To provide a review of recent literature on the epidemiology, natural history, and risk factors for OM.

DATA SOURCES AND REVIEW METHODS

A search of OM articles in English published July 2007 to June 2011 was conducted using PubMed and related databases. Those with findings judged of importance for epidemiology, public health, and/or statistical methods were reviewed.

RESULTS

The literature has continued to expand, increasing understanding of the worldwide burden of OM in childhood, complications from treatment failures, and comorbidities. Novel risk factors, including genetic factors, have been examined for OM susceptibility. Population-based studies in Canada, the United States, and other countries confirmed reductions in OM prevalence. Although most studies concentrated on acute OM (AOM) or OM with effusion (OME), a few examined severe chronic suppurative OM (CSOM), a major public health problem in developing countries and for certain indigenous populations around the world.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

Recent publications have reinforced earlier epidemiological findings, while extending our knowledge in human population groups with high burden of OM.

Cytokine responses in the common cold and otitis media

Cytokines are a group of diverse molecules that influence the function of every organ system. They are most well studied in their effects on the immune system and their integral role in mediating inflammation. The common cold and otitis media are two such disease states, and much has been learned about the various effects of cytokines in each disease. Most often the viruses isolated include rhinovirus (RV), respiratory syncytial virus (RSV), adenovirus, coronavirus, and picornavirus. Otitis media, sinusitis, bronchiolitis, pneumonia, and asthma exacerbation are commonly accepted as complications of viral upper respiratory tract infections. Furthermore, otitis media and upper respiratory infections are inextricably linked in that the majority (>70 %) of cases of acute otitis media occur as complications of the common cold. Cytokine polymorphisms have been associated with the severity of colds as well as the frequency of otitis media. This article attempts to update the reader on various studies that have recently been published regarding the role of cytokines in these two disease entities.

Viral-bacterial interactions in acute otitis media

Acute otitis media (AOM) is a polymicrobial disease, which usually occurs as a complication of viral upper respiratory tract infection (URI). While respiratory viruses alone may cause viral AOM, they increase the risk of bacterial middle ear infection and worsen clinical outcomes of bacterial AOM. URI viruses alter Eustachian tube (ET) function via decreased mucociliary action, altered mucus secretion and increased expression of inflammatory mediators among other mechanisms. Transient reduction in protective functions of the ET allows colonizing bacteria of the nasopharynx to ascend into the middle ear and cause AOM. Advances in research help us to better understand the host responses to viral URI, the mechanisms of viral-bacterial interactions in the nasopharynx and the development of AOM. In this review, we present current knowledge regarding viral-bacterial interactions in the pathogenesis and clinical course of AOM. We focus on the common respiratory viruses and their established role in AOM.

Replication of respiratory syncytial virus is inhibited by the host defense molecule viperin

Respiratory syncytial virus (RSV) is an important viral pathogen of otitis media, bronchiolitis, and pneumonia. As infection of the upper airways is a precondition for the development of these diseases, understanding RSV pathogenesis and the host response induced by RSV in this niche may enable the development of novel therapeutic strategies against this virus. We have used a microarray approach and showed that expression of the gene that encodes the antiviral protein viperin was significantly upregulated in the chinchilla nasopharynx up to 1 week after RSV challenge. Overexpression of human viperin in vitro diminished the ability of RSV to infect HeLa or A549 cells. Furthermore, transduction of the chinchilla airways with a recombinant adeno-associated virus vector that encodes viperin resulted in reduced titers of RSV in the nasopharyngeal lavage fluid. Collectively, these data indicated that viperin plays a significant role in the innate immune defense against RSV.

Etiological diagnosis reduces the use of antibiotics in infants with bronchiolitis

OBJECTIVE

Acute bronchiolitis is a leading cause of infant hospitalization and is most commonly caused by respiratory syncytial virus. Etiological tests are not required for its diagnosis, but the influence of viral screening on the therapeutic approach for acute bronchiolitis remains unclear.

METHODS

A historical cohort was performed to assess the impact of viral screening on drug prescriptions. The study included infants up to one year of age who were hospitalized for bronchiolitis. Virus screening was performed using immunofluorescence assays in nasopharyngeal aspirates. The clinical data were obtained from the patients' medical records. Therapeutic changes were considered to be associated with viral screening when made within 24 hours of the release of the results.

RESULTS

The frequency of prescriptions for beta agonists, corticosteroids and antibiotics was high at the time of admission and was similar among the 230 patients. The diagnosis of pneumonia and otitis was associated with the introduction of antibiotics but did not influence antibiotics maintenance after the results of the virus screening were obtained. Changes in the prescriptions were more frequent for the respiratory syncytial virus patients compared to patients who had negative viral screening results (p =0.004), especially the discontinuation of antibiotics (p<0.001). The identification of respiratory syncytial virus was associated with the suspension of antibiotics (p= 0.003), even after adjusting for confounding variables (p = 0.004); however, it did not influence the suspension of beta-agonists or corticosteroids.

CONCLUSION

The identification of respiratory syncytial virus in infants with bronchiolitis was independently associated with the discontinuation of antibiotics during hospitalization.

High detection rates of nucleic acids of a wide range of respiratory viruses in the nasopharynx and the middle ear of children with a history of recurrent acute otitis media

Both bacteria and viruses play a role in the development of acute otitis media, however, the importance of specific viruses is unclear. In this study molecular methods were used to determine the presence of nucleic acids of human rhinoviruses (HRV; types A, B, and C), respiratory syncytial viruses (RSV; types A and B), bocavirus (HBoV), adenovirus, enterovirus, coronaviruses (229E, HKU1, NL63, and OC43), influenza viruses (types A, B, and C), parainfluenza viruses (types 1, 2, 3, 4A, and 4B), human metapneumovirus, and polyomaviruses (KI and WU) in the nasopharynx of children between 6 and 36 months of age either with (n = 180) or without (n = 66) a history of recurrent acute otitis media and in 238 middle ear effusion samples collected from 143 children with recurrent acute otitis media. The co‐detection of these viruses with Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis was analyzed. HRV (58.3% vs. 42.4%), HBoV (52.2% vs. 19.7%), polyomaviruses (36.1% vs. 15.2%), parainfluenza viruses (29.4% vs. 9.1%), adenovirus (25.0% vs. 6.1%), and RSV (27.8% vs. 9.1%) were detected significantly more often in the nasopharynx of children with a history of recurrent acute otitis media compared to healthy children. HRV was predominant in the middle ear and detected in middle ear effusion of 46% of children. Since respiratory viruses were detected frequently in the nasopharynx of both children with and without a history of recurrent acute otitis media, the etiological role of specific viruses in recurrent acute otitis media remains uncertain, however, anti‐viral therapies may be beneficial in future treatment and prevention strategies for acute otitis media. J. Med. Virol. 83:2008–2017, 2011. © 2011 Wiley‐Liss, Inc.

Viral-bacterial interactions and risk of acute otitis media complicating upper respiratory tract infection

Acute otitis media (AOM) is a common complication of upper respiratory tract infection whose pathogenesis involves both viruses and bacteria. We examined risks of acute otitis media associated with specific combinations of respiratory viruses and acute otitis media bacterial pathogens. Data were from a prospective study of children ages 6 to 36 months and included viral and bacterial culture and quantitative PCR for respiratory syncytial virus (RSV), human bocavirus, and human metapneumovirus. Repeated-measure logistic regression was used to assess the relationship between specific viruses, bacteria, and the risk of acute otitis media complicating upper respiratory tract infection. In unadjusted analyses of data from 194 children, adenovirus, bocavirus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis were significantly associated with AOM (P < 0.05 by χ(2) test). Children with high respiratory syncytial virus loads (≥3.16 × 10(7) copies/ml) experienced increased acute otitis media risk. Higher viral loads of bocavirus and metapneumovirus were not significantly associated with acute otitis media. In adjusted models controlling for the presence of key viruses, bacteria, and acute otitis media risk factors, acute otitis media risk was independently associated with high RSV viral load with Streptococcus pneumoniae (odds ratio [OR], 4.40; 95% confidence interval [CI], 1.90 and 10.19) and Haemophilus influenzae (OR, 2.04; 95% CI, 1.38 and 3.02). The risk was higher for the presence of bocavirus and H. influenzae together (OR, 3.61; 95% CI, 1.90 and 6.86). Acute otitis media risk differs by the specific viruses and bacteria involved. Acute otitis media prevention efforts should consider methods for reducing infections caused by respiratory syncytial virus, bocavirus, and adenovirus in addition to acute otitis media bacterial pathogens.

Unraveling the genetics of otitis media: from mouse to human and back again

Otitis media (OM) is among the most common illnesses of early childhood, characterised by the presence of inflammation in the middle ear cavity. Acute OM and chronic OM with effusion (COME) affect the majority of children by school age and have heritability estimates of 40-70%. However, the majority of genes underlying this susceptibility are, as yet, unidentified. One method of identifying genes and pathways that may contribute to OM susceptibility is to look at mouse mutants displaying a comparable phenotype. Single-gene mouse mutants with OM have identified a number of genes, namely, Eya4, Tlr4, p73, MyD88, Fas, E2f4, Plg, Fbxo11, and Evi1, as potential and biologically relevant candidates for human disease. Recent studies suggest that this "mouse-to-human" approach is likely to yield relevant data, with significant associations reported between polymorphisms at the FBXO11, TLR4, and PAI1 genes and disease in humans. An association between TP73 and chronic rhinosinusitis has also been reported. In addition, the biobanks of available mouse mutants provide a powerful resource for functional studies of loci identified by future genome-wide association studies of OM in humans. Mouse models of OM therefore are an important component of current approaches attempting to understand the complex genetic susceptibility to OM in humans, and which aim to facilitate the development of preventative and therapeutic interventions for this important and common disease.

Increased prevalence of otitis media following respiratory syncytial virus infection

AIM

The aim of this study was to analyse whether, during the 18 months following a respiratory syncytial virus (RSV) infection in infants, there were differences in the prevalence of common infections such as acute otitis media (AOM), compared with controls. We also wanted to see whether passive smoking could be a contributory factor.

METHODS

In a longitudinal study, 33 children who attended the emergency room with an RSV infection (age < or = 7 months) were compared with 37 age-matched controls recruited from routine infant check-ups. The 18-month follow-up consisted of a questionnaire focusing on environmental factors and the child's health during the last 12 months. An allergy skin prick test (SPT) was performed and venous blood was obtained.

RESULTS

The prevalence of AOM and the use of antibiotics were higher in the RSV group than in the controls (p = 0.009 and p = 0.027 respectively). The number of AOMs and the use of antibiotics correlated, r = 0.8. In the RSV group, one or both parents smoked in 52% compared with 14% in the controls (p < 0.001). There were no differences in allergy SPT results.

CONCLUSION

The infants with RSV infection had AOM and were prescribed antibiotics more frequently during the follow-up period. Furthermore, smoking was far more common among the parents of the RSV group. We speculate that passive smoking could be a contributory factor to the infections noted here.

Clinical characteristics of respiratory syncytial virus infection-associated acute otitis media

BACKGROUND

It is known that children with respiratory syncytial virus (RSV) infection frequently have complications of acute otitis media (AOM).

METHODS

The hospital records of 148 inpatients aged 6-35 months who had RSV infection between January 2004 and December 2007, were retrospectively investigated.

RESULTS

Forty-six out of 148 children (31%) had AOM. There was a significantly greater number of children with fever who had AOM (P = 0.005). The percentage of children with beta-lactamase-non-producing ampicillin-resistant (BLNAR) Haemophilus influenzae in nasopharyngeal culture who had AOM showed a tendency to be greater than that of those who did not have AOM, but this was not statistically significant (P = 0.068). Moreover, BLNAR H. influenzae was positive in middle ear fluid specimens from four of five children with AOM who underwent tympanocentesis. There were no significant differences in the incidence of lower airway infection, leukocytes counts, or serum C-reactive protein levels between children with and without AOM.

CONCLUSIONS

Children who had RSV infection with AOM had a higher incidence of fever than those without AOM.

Systemic cytokine response profiles associated with respiratory virus-induced acute otitis media

BACKGROUND

Acute otitis media (AOM) results from a complex interplay between the infectious agents and host immune responses. Cytokines play a major role in the pathogenesis of AOM, but there are few studies on the systemic cytokine response during AOM.

METHODS

Sera were collected from 145 children (median age = 13.5 months) at the time of diagnosis of AOM. Concentrations of 17 cytokines (IL-1beta, -2, -4, -5, -6, -7, -8, -10, -12, -13, -17, granulocyte-colony stimulating factor (G-CSF), granulocyte-monocyte-colony stimulating factor, interferon-gamma, MCP-1, MIP-1beta, TNF-alpha) were determined and correlated with viral etiology and clinical outcome. The statistical analysis was conducted using bioinformatics software.

RESULTS

Cluster patterns of concentrations of cytokines were examined by unsupervised hierarchical clustering algorithms. Four major cluster groups were identified, one of the groups was significantly enriched for cases of respiratory syncytial virus (RSV)-induced AOM as compared with other viruses. Specifically, RSV-induced AOM had significantly higher concentrations of G-CSF, MCP-1, IL-10, IL-6, interferon-gamma, and IL-8 (P < 0.05). Using a decision tree classifier, higher G-CSF concentrations produced 87.6% accuracy to predict RSV-induced AOM. Overall, higher IL-13 concentrations produced 84.2% accuracy to predict early clinical failure of antibiotic treatment.

CONCLUSIONS

Children with AOM have a unique pattern of systemic cytokine response that relates to virus etiology and clinical outcome. Based on G-CSF and IL-13 measurements, it is possible to accurately classify RSV-induced AOM and early treatment failure, respectively; these observations will need to be validated in an independent population.

Recombinant simian varicella viruses expressing respiratory syncytial virus antigens are immunogenic

Recombinant simian varicella viruses (rSVVs) were engineered to express respiratory syncytial virus (RSV) antigens. The RSV surface glycoprotein G and second matrix protein M2 (22k) genes were cloned into the SVV genome, and recombinant viruses were characterized in vitro and in vivo. rSVVs were also engineered to express the membrane-anchored or secreted forms of the RSV-G protein as well as an RSV G lacking its chemokine mimicry motif (CX3C), which may have different effects on priming the host immune response. The RSV genes were efficiently expressed in rSVV/RSV-infected Vero cells as RSV-G and -M2 transcripts were detected by RT-PCR, and RSV antigens were detected by immunofluorescence and immunoblot assays. The rSVVs replicated efficiently in Vero cell culture. Rhesus macaques immunized with rSVV/RSV-G and rSVV/RSV-M2 vaccines produced antibody responses to SVV and RSV antigens. The results demonstrate that recombinant varicella viruses are suitable vectors for the expression of RSV antigens and may represent a novel vaccine strategy for immunization against both pathogens.

Respiratory viruses other than influenza virus: impact and therapeutic advances

Though several antivirals have been developed and marketed to treat influenza virus infections, the development of antiviral agents with clinical activity against other respiratory viruses has been more problematic. Here we review the epidemiology of respiratory viral infections in immunocompetent and immunocompromised hosts, examine the evidence surrounding the currently available antivirals for respiratory viral infections other than influenza, highlight those that are in the pipeline, and discuss the hurdles for development of such agents.

Viral upper respiratory tract infection and otitis media complication in young children

BACKGROUND

The common cold or upper respiratory infection (URI) is highly prevalent among young children and often results in otitis media (OM). The incidence and characteristics of OM complicating URI due to specific viruses have not been well studied.

METHODS

We performed a prospective, longitudinal cohort study of 294 healthy children (age range, 6 months to 3 years). Each child was observed for 1 year to assess the occurrence of URI, acute OM (AOM), and OM with effusion (OME) complicating URI due to specific viruses.

RESULTS

We documented 1295 URI episodes (5.06 episodes per child-year) and 440 AOM episodes (1.72 episodes per child-year). Virus studies were performed for 864 URI episodes; 63% were virus positive. Rhinovirus and adenovirus were most frequently detected during URI. The overall incidence of OM that complicated URI was 61%, including a 37% incidence of AOM and a 24% incidence of OME. Young age was the most important predictor of AOM that complicated URI. AOM occurred in approximately one-half of children with URI due to adenovirus, respiratory syncytial virus, or coronavirus and in approximately one-third of those with URI due to influenza virus, parainfluenza virus, enterovirus, or rhinovirus.

CONCLUSIONS

More than 60% of episodes of symptomatic URI among young children were complicated by AOM and/or OME. Young age and specific virus types were predictors of URI complicated by AOM. For young children, the strategy to prevent OM should involve prevention of viral URI. The strategy may be more effective if the priority is given to development of means to prevent URI associated with adenovirus and respiratory syncytial virus.

Audiologic results in patients with Moebiüs sequence

OBJECTIVE

Moebiüs sequence is a pathology not very well understood regarding to the hearing status. The main goal of this study was to describe the audiologic findings in children and adolescent who carry Moebiüs sequence.

METHOD

Participated in this study 17 children and adolescent, with age ranging from 3 to 13 years old. Prior to the testing, the family answered an interview. It was realized external auditory canal inspection, and the hearing testing (auditory instrumentation, pure tone audiometry, speech audiometry, immittanciometric measures, and otoacoustic emissions) on the participants.

RESULTS

The auditory instrumentation evaluation (n=6) was present in all participants. The pure tone audiometry presented normal hearing levels in 75.0% of the tested ears, one ear with conductive hearing loss, two ears with sensory neural hearing loss, and one ear with mixed hearing loss. The tympanometric measures showed Type A tympanograms in 63.0% of the ears, Type B in 11.1%, Type C in 18.5%, and Type As in 7.4%. T the acoustic reflexes measure showed contralateral acoustic reflexes present in 50.0% of the ears, and ipsilateral acoustic reflexes present in 34.6% ears. The OAE results showed presence in 73.0%, for the TOAE, and 76.9% for the DPOAE.

CONCLUSION

These results support the idea that there is no audiologic pattern for conductive hearing loss. The majority of the participants presented hearing in the normal range. Care should be taken in drawing conclusions regarding to auditory status of the individual with Moebiüs sequence, but what can be said is that not always those individuals present hearing loss.