Panel 6: Vaccines

Identifying the Microbiome of the Adenoid Surface of Children Suffering from Otitis Media with Effusion and Children without Middle Ear Effusion Using 16S rRNA Genetic Sequencing

BACKGROUND

The upper respiratory tract harbors diverse communities of commensal, symbiotic, and pathogenic organisms, originating from both the oral and nasopharyngeal microbiota. Among the primary sites of microbial colonization in the upper airways are the adenoids. Alterations in the adenoid microbiota have been implicated in the development of various conditions, including secretory otitis media.

AIM

This study aims to employ 16S rRNA genetic sequencing to identify the most common bacteria present on the surface of adenoids in children with otitis media with effusion and compare them with children without pathologies in the tympanic cavity. Additionally, we seek to determine and compare the bacterial diversity in these two study groups.

MATERIALS AND METHODS

A total of nineteen samples from the adenoid surfaces were collected, comprising two groups: thirteen samples from children without middle ear effusion and six samples from children with secretory otitis media. The libraries of the V3-V4 hypervariable region of the bacterial 16S rRNA gene was made and sequenced using MiSeq platform.

RESULTS

The most prevalent phyla observed in both groups were Proteobacteria, Firmicutes, and Bacteroidetes. The most common bacterial genera identified in both groups were Haemophilus, Streptococcus, Moraxella, Fusobacterium, and Bordetella, with Fusobacterium and Moraxella being more prevalent in the groups that had no middle ear effusion, while Haemophulus and Streptococcus were more prevalent in the otitis media with effusion group, although not in a statistically significant way. Statistical analysis shows a trend towards bacterial composition and beta diversity being similar between the study groups; however, due to the limited sample size and unevenness between groups, we should approach this data with caution.

CONCLUSION

The lack of prolific difference in bacterial composition between the study groups suggests that the role of the adenoid microbiome in the development of otitis media with effusion may be less significant.

An indirect treatment comparison (ITC) and matching-adjusted indirect comparison (MAIC) between a 15-valent (V114) and a 20-valent (PCV20) pneumococcal conjugate vaccine among healthy infants

OBJECTIVES

Immunogenicity between 15-valent V114 (PCV15) and 20-valent PCV20 pneumococcal conjugate vaccines in healthy infants is compared in an indirect treatment comparison and matching-adjusted indirect comparison. Hypotheses: immunogenicity of V114 is non-inferior to PCV20 for all PCV13 serotypes, and superior to PCV20 for serotype 3 based on lower bound margins.

METHODS

Two phase 3 pivotal studies on 3 + 1 pediatric vaccination schedule at age 2, 4, 6, and 12-15 months compared V114 (N = 858) to PCV13 (N = 856) and PCV20 (N = 1001) to PCV13 (N = 987). Infant's age and race in V114 study were matched to those in PCV20 study. Primary endpoints were serotype-specific Immunoglobulin G (IgG) response rate difference (RRD) 30 days post-dose (PD)3; IgG geometric mean concentration (GMC) ratios 30 days PD3 and PD4.

RESULTS

V114 was non-inferior (m a r g i n R R D >-10%-point; m a r g i n G M C r a t i o >0.5) to PCV20 (p-value <0.001) for all endpoints. V114 was superior (m a r g i n R R D >0%-point; m a r g i n G M C r a t i o >1.2) to PCV20 (p-value <0.001) for serotype 3: RRD was 34.5% (95%CI 27.9%-41.1%) PD3, and IgG GMC ratios were 2.39 (95%CI 2.12-2.68) PD3 and 2.15 (95%CI 1.90-2.41) PD4.

CONCLUSION

Immune response to V114 administered in a 3 + 1 schedule in healthy infants was considered non-inferior to PCV20 for all 13 PCV13 serotypes and superior for serotype 3 PD3 and PD4.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifiers NCT03893448, NCT04382326.

Temporomandibular Joint and Otitis Media: A Narrative Review of Implications in Etiopathogenesis and Treatment

Otitis media (OM) and its recurring (rAOM), effusive (OME), and chronic forms, represent a frequent clinical challenge. The middle ear, the mandible, and the temporomandibular joint (TMJ) share several embryological and anatomical connections. Despite that, the role of mandibular malposition and TMJ dysfunction is frequently overlooked in the management of otitis media. In this narrative review, we present current evidence supporting the etiopathogenetic role of a dysfunctional stomatognathic system in the onset of OM and the effectiveness of orthognathic treatment in preventing rAOM and OME. In particular, a focus on the influence of TMJ on Eustachian tube function is provided.

Recurrent Acute Otitis Media Environmental Risk Factors: A Literature Review from the Microbiota Point of View

Acute otitis media (AOM) constitutes a multifactorial disease, as several host and environmental factors contribute to its occurrence. Prevention of AOM represents one of the most important goals in pediatrics, both in developing countries, in which complications, mortality, and deafness remain possible consequences of the disease, compared to in developed countries, in which this condition has an important burden in terms of medical, social, and economical implications. The strategies for AOM prevention are based on reducing the burden of risk factors, through the application of behavioral, environmental, and therapeutic interventions. The introduction of culture-independent techniques has allowed high-throughput investigation of entire bacterial communities, providing novel insights into the pathogenesis of middle ear diseases through the identification of potential protective bacteria. The upper respiratory tract (URT) is a pivotal region in AOM pathogenesis, as it could act as a source of pathogens than of protective microorganisms for the middle ear (ME). Due to its direct connection with the external ambient, the URT is particularly exposed to the influence of environmental agents. The aim of this review was to evaluate AOM environmental risk factors and their impact on URT microbial communities, and to investigate AOM pathogenesis from the microbiota perspective.

Population-based otoscopic and audiometric assessment of a birth cohort recruited for a pneumococcal vaccine trial 15-18 years earlier: a protocol

INTRODUCTION

A cohort of 12 000 children in the Philippines who had enrolled in a 2000-2004 (current ages 16 to 20 years) Phase 3 11-valent pneumococcal conjugate vaccine for the prevention of radiographically confirmed pneumonia are now being asked to participate in a separate study (expected completion date September 2021) to assess the cohort's current long-term audiometric and otologic status. This new study would allow assessments of the utility of the pneumococcal vaccine in conferring its protective effects on the long-term sequelae of otitis media (OM), if any. Lack of trained local healthcare providers in otolaryngology/audiology and testing equipment in Bohol, Philippines, necessitates the development of a distinct methodology that would lead to meaningful data analysis.

METHODS AND ANALYSIS

Reliable data collection and transfer are achieved by a US otolaryngologist/audiologist team training local nurses on all procedures in a didactic and hands-on process. An assortment of portable otolaryngologic and audiologic equipment suitable for field testing has been acquired, including an operating otoscope (Welch-Allyn), a video-otoscope (JedMed), a tympanometer with distortion product otoacoustic emission measurements (Path Sentiero) and a screening audiometer (HearScreen). Data will then be uploaded to a Research Electronic Data Capture database in the USA.Tympanometric and audiologic data will be codified through separate conventional algorithms. A team of paediatric otolaryngology advanced practice providers (APPs) have been trained and validated in interpreting video otoscopy. The protocol for classification of diagnostic outcome variables based on video otoscopy and tympanometry has been developed and is being used by APPs to evaluate all otoscopy data.

ETHICS AND DISSEMINATION

The study was approved by the Research Institute of Tropical Medicine, Alabang, Manila, Philippines, and the institutional review board and the Colorado Multiple Institutional Review Board of the University of Colorado School of Medicine, Aurora, Colorado, USA.Research results will be made available to children and their caregivers with abnormal audiologic outcomes, the funders and other researchers.

TRIAL REGISTRATION NUMBER

ISRCTN 62323832; Post-results.

Awareness and attitudes of Saudi parents toward otitis media in children

Background:

An ear infection is a common health problem in children. Parents’ awareness about otitis media (OM) among children, varies across the world. We aimed to explore parents’ knowledge, attitude, and practices toward OM among their children.

Methods:

A quantitative cross-sectional study was done from May 1, 2020 to June 30, 2020, in Qassim, Saudi Arabia.

Results:

This study comprised 703 participants; Mothers comprised the majority (77.1%), 43.2% of the participants were aged between 31 and 40 years of age, and 73% of them had Bachelor's degrees or diplomas. More than half of the participants had suboptimal knowledge of OM. Although the result showed that 56% of them had positive attitudes, 86.6% did not view vaccination as a prevention measure of acute OM (AOM). Besides, 81.8% of parents were willing to follow the watchful waiting approach, in case their child had OM.

Conclusion:

Most of the parents in the Qassim region have inadequate knowledge regarding OM among children. Based on our result findings, we recommend further education programs to enhance the knowledge regarding OM and AOM, among the Qassim population, Saudi Arabia including family members of patients and the healthcare workers.

Pneumococcal conjugate vaccines for preventing acute otitis media in children

BACKGROUND

Prior to introducing pneumococcal conjugate vaccines (PCVs), Streptococcus pneumoniae was most commonly isolated from the middle ear fluid of children with acute otitis media (AOM). Reducing nasopharyngeal colonisation of this bacterium by PCVs may lead to a decline in AOM. The effects of PCVs deserve ongoing monitoring since studies from the post-PCV era report a shift in causative otopathogens towards non-vaccine serotypes and other bacteria. This updated Cochrane Review was first published in 2002 and updated in 2004, 2009, 2014, and 2019.

OBJECTIVES

To assess the effect of PCVs in preventing AOM in children up to 12 years of age.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, Web of Science, and two trials registers, ClinicalTrials.gov and WHO ICTRP, to 11 June 2020.

SELECTION CRITERIA

Randomised controlled trials of PCV versus placebo or control vaccine.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. The primary outcomes were frequency of all-cause AOM and adverse effects. Secondary outcomes included frequency of pneumococcal AOM and frequency of recurrent AOM (defined as three or more AOM episodes in six months or four or more in one year). We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included 15 publications of 11 trials (60,733 children, range 74 to 37,868 per trial) of 7- to 11-valent PCVs versus control vaccines (meningococcus type C vaccine in three trials, and hepatitis A or B vaccine in eight trials). We included one additional publication of a previously included trial for this 2020 update. We did not find any relevant trials with the newer 13-valent PCV. Most studies were funded by pharmaceutical companies. Overall, risk of bias was low. In seven trials (59,415 children), PCVs were administered in early infancy, whilst four trials (1318 children) included children aged one year and over who were either healthy or had a history of respiratory illness. There was considerable clinical heterogeneity across studies, therefore we reported results from individual studies. PCV administered in early infancy PCV7 The licenced 7-valent PCV with CRM197 as carrier protein (CRM197-PCV7) was associated with a 6% (95% confidence interval (CI) -4% to 16%; 1 trial; 1662 children) and 6% (95% CI 4% to 9%; 1 trial; 37,868 children) relative risk reduction (RRR) in low-risk infants (moderate-certainty evidence), but was not associated with a reduction in all-cause AOM in high-risk infants (RRR -5%, 95% CI -25% to 12%). PCV7 with the outer membrane protein complex of Neisseria meningitidis serogroup B as carrier protein (OMPC-PCV7) was not associated with a reduction in all-cause AOM (RRR -1%, 95% CI -12% to 10%; 1 trial; 1666 children; low-certainty evidence). CRM197-PCV7 and OMPC-PCV7 were associated with 20% (95% CI 7% to 31%) and 25% (95% CI 11% to 37%) RRR in pneumococcal AOM, respectively (2 trials; 3328 children; high-certainty evidence), and CRM197-PCV7 with 9% (95% CI -12% to 27%) and 10% (95% CI 7% to 13%) RRR in recurrent AOM (2 trials; 39,530 children; moderate-certainty evidence). PHiD-CV10/11 The effect of a licenced 10-valent PCV conjugated to protein D, a surface lipoprotein of Haemophilus influenzae, (PHiD-CV10) on all-cause AOM in healthy infants varied from 6% (95% CI -6% to 17%; 1 trial; 5095 children) to 15% (95% CI -1% to 28%; 1 trial; 7359 children) RRR (low-certainty evidence). PHiD-CV11 was associated with 34% (95% CI 21% to 44%) RRR in all-cause AOM (1 trial; 4968 children; moderate-certainty evidence). PHiD-CV10 and PHiD-CV11 were associated with 53% (95% CI 16% to 74%) and 52% (95% CI 37% to 63%) RRR in pneumococcal AOM (2 trials; 12,327 children; high-certainty evidence), and PHiD-CV11 with 56% (95% CI -2% to 80%) RRR in recurrent AOM (1 trial; 4968 children; low-certainty evidence). PCV administered at a later age PCV7 We found no evidence of a beneficial effect on all-cause AOM of administering CRM197-PCV7 in children aged 1 to 7 years with a history of respiratory illness or frequent AOM (2 trials; 457 children; moderate-certainty evidence) and CRM197-PCV7 combined with a trivalent influenza vaccine in children aged 18 to 72 months with a history of respiratory tract infections (1 trial; 597 children; moderate-certainty evidence). CRM197-PCV9 In 1 trial including 264 healthy daycare attendees aged 1 to 3 years, CRM197-PCV9 was associated with 17% (95% CI -2% to 33%) RRR in parent-reported all-cause otitis media (very low-certainty evidence). Adverse events Nine trials reported on adverse effects (77,389 children; high-certainty evidence). Mild local reactions and fever were common in both groups, and occurred more frequently in PCV than in control vaccine groups: redness (< 2.5 cm): 5% to 20% versus 0% to 16%; swelling (< 2.5 cm): 5% to 12% versus 0% to 8%; and fever (< 39 °C): 15% to 44% versus 8% to 25%. More severe redness (> 2.5 cm), swelling (> 2.5 cm), and fever (> 39 °C) occurred less frequently (0% to 0.9%, 0.1% to 1.3%, and 0.4% to 2.5%, respectively) in children receiving PCV, and did not differ significantly between PCV and control vaccine groups. Pain or tenderness, or both, was reported more frequently in PCV than in control vaccine groups: 3% to 38% versus 0% to 8%. Serious adverse events judged to be causally related to vaccination were rare and did not differ significantly between groups, and no fatal serious adverse event judged causally related to vaccination was reported.

AUTHORS' CONCLUSIONS

Administration of the licenced CRM197-PCV7 and PHiD-CV10 during early infancy is associated with large relative risk reductions in pneumococcal AOM. However, the effects of these vaccines on all-cause AOM is far more uncertain based on low- to moderate-certainty evidence. We found no evidence of a beneficial effect on all-cause AOM of administering PCVs in high-risk infants, after early infancy, and in older children with a history of respiratory illness. Compared to control vaccines, PCVs were associated with an increase in mild local reactions (redness, swelling), fever, and pain and/or tenderness. There was no evidence of a difference in more severe local reactions, fever, or serious adverse events judged to be causally related to vaccination.

Upper Respiratory Tract Microbiome and Otitis Media Intertalk: Lessons from the Literature

Otitis media (OM) is one of the most common diseases occurring during childhood. Microbiological investigations concerning this topic have been primarily focused on the four classical otopathogens (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pyogenes) mainly because most of the studies have been conducted with culture-dependent methods. In recent years, the introduction of culture-independent techniques has allowed high-throughput investigation of entire bacterial communities, leading to a better comprehension of the role of resident flora in health and disease. The upper respiratory tract (URT) is a region of major interest in otitis media pathogenesis, as it could serve as a source of pathogens for the middle ear (ME). Studies conducted with culture-independent methods in the URT and ME have provided novel insights on the pathogenesis of middle ear diseases through the identification of both possible new causative agents and of potential protective bacteria, showing that imbalances in bacterial communities could influence the natural history of otitis media in children. The aim of this review is to examine available evidence in microbiome research and otitis media in the pediatric age, with a focus on its different phenotypes: acute otitis media, otitis media with effusion and chronic suppurative otitis media.

Moraxella catarrhalis phase-variable loci show differences in expression during conditions relevant to disease

Moraxella catarrhalis is a human-adapted, opportunistic bacterial pathogen of the respiratory mucosa. Although asymptomatic colonization of the nasopharynx is common, M. catarrhalis can ascend into the middle ear, where it is a prevalent causative agent of otitis media in children, or enter the lower respiratory tract, where it is associated with acute exacerbations of chronic obstructive pulmonary disease in adults. Phase variation is the high frequency, random, reversible switching of gene expression that allows bacteria to adapt to different host microenvironments and evade host defences, and is most commonly mediated by simple DNA sequence repeats. Bioinformatic analysis of five closed M. catarrhalis genomes identified 17 unique simple DNA sequence repeat tracts that were variable between strains, indicating the potential to mediate phase variable expression of the associated genes. Assays designed to assess simple sequence repeat variation under conditions mimicking host infection demonstrated that phase variation of uspA1 (ubiquitous surface protein A1) from high to low expression occurs over 72 hours of biofilm passage, while phase variation of uspA2 (ubiquitous surface protein A2) to high expression variants occurs during repeated exposure to human serum, as measured by mRNA levels. We also identify and confirm the variable expression of two novel phase variable genes encoding a Type III DNA methyltransferase (modO), and a conserved hypothetical permease (MC25239_RS00020). These data reveal the repertoire of phase variable genes mediated by simple sequence repeats in M. catarrhalis and demonstrate that modulation of expression under conditions mimicking human infection is attributed to changes in simple sequence repeat length.

Panel 8: Vaccines and immunology

OBJECTIVE

To review and highlight significant advances made towards vaccine development and understanding of the immunology of otitis media (OM) since the 19th International Symposium on Recent Advances in Otitis Media (ISOM) in 2015, as well as identify future research directions and knowledge gaps.

DATA SOURCES

PubMed database, National Library of Medicine.

REVIEW METHODS

Key topics were assigned to each panel member for detailed review. Draft reviews were collated, circulated, and thoroughly discussed when the panel met at the 20th ISOM in June 2019. The final manuscript was prepared with input from all panel members.

CONCLUSIONS

Since 2015 there have been a number of studies assessing the impact of licensed pneumococcal vaccines on OM. While these studies have confirmed that these vaccines are effective in preventing carriage and/or disease caused by vaccine serotypes, OM caused by non-vaccine serotype pneumococci and other otopathogens remains a significant health care burden globally. Development of multi-species vaccines is challenging but essential to reducing the global burden of OM. Influenza vaccination has been shown to prevent acute OM, and with novel vaccines against nontypeable Haemophilus influenzae (NTHi), Moraxella catarrhalis and Respiratory Syncytial Virus (RSV) in clinical trials, the potential to significantly prevent OM is within reach. Research into alternative vaccine delivery strategies has demonstrated the power of maternal and mucosal vaccination for OM prevention. Future OM vaccine trials must include molecular diagnostics of middle ear effusion, for detection of viruses and bacteria that are persisting in biofilms and to enable accurate assessment of vaccine impact on OM etiology. Understanding population differences in natural and vaccine-induced immune responses to otopathogens is also important for development of the most effective OM vaccines. Improved understanding of the interaction between otopathogens will also advance development of effective therapies and encourage the assessment of the indirect benefits of vaccination.

IMPLICATIONS FOR PRACTICE

While NTHi and M. catarrhalis are the predominant otopathogens, funding opportunities to drive vaccine development for these species are limited due to a focus on prevention of childhood mortality rather than morbidity. Delivery of a comprehensive report on the high financial and social costs of OM, including the potential for OM vaccines to reduce antibiotic use and subsequent development of antimicrobial resistance (AMR), would likely assist in engaging stakeholders to recognize the value of prevention of OM and increase support for efforts on OM vaccine development. Vaccine trials with OM prevention as a clinical end-point are challenging, however a focus on developing assays that measure functional correlates of protection would facilitate OM vaccine development.

Vinpocetine Suppresses Streptococcus pneumoniae-Induced Inflammation via Inhibition of ERK1 by CYLD

Otitis media (OM) is the most common bacterial infection in children. It remains a major health problem and a substantial socioeconomic burden. Streptococcus pneumoniae (S. pneumoniae) is one of the most common bacterial pathogens causing OM. Innate inflammatory response plays a critical role in host defense against bacterial pathogens. However, if excessive, it has a detrimental impact on the middle ear, leading to middle ear inflammation, a hallmark of OM. Currently, there has been limited success in developing effective therapeutic agents to suppress inflammation without serious side effects. In this study, we show that vinpocetine, an antistroke drug, suppressed S. pneumoniae-induced inflammatory response in cultured middle ear epithelial cells as well as in the middle ear of mice. Interestingly, vinpocetine inhibited S. pneumoniae-induced inflammation via upregulating a key negative regulator cylindromatosis (CYLD). Moreover, CYLD suppressed S. pneumoniae-induced inflammation via inhibiting the activation of ERK. Importantly, the postinfection administration of vinpocetine markedly inhibited middle ear inflammation induced by S. pneumoniae in a well-established mouse OM model. These studies provide insights into the molecular mechanisms underlying the tight regulation of inflammation via inhibition of ERK by CYLD and identified vinpocetine as a potential therapeutic agent for suppressing the inflammatory response in the pathogenesis of OM via upregulating negative regulator CYLD expression.

The Moraxella catarrhalis phase-variable DNA methyltransferase ModM3 is an epigenetic regulator that affects bacterial survival in an in vivo model of otitis media

Background

Moraxella catarrhalis is a leading cause of otitis media (OM) and chronic obstructive pulmonary disease (COPD). M. catarrhalis contains a Type III DNA adenine methyltransferase (ModM) that is phase-variably expressed (i.e., its expression is subject to random, reversible ON/OFF switching). ModM has six target recognition domain alleles (modM1–6), and we have previously shown that modM2 is the predominant allele, while modM3 is associated with OM. Phase-variable DNA methyltransferases mediate epigenetic regulation and modulate pathogenesis in several bacteria. ModM2 of M. catarrhalis regulates the expression of a phasevarion containing genes important for colonization and infection. Here we describe the phase-variable expression of modM3, the ModM3 methylation site and the suite of genes regulated within the ModM3 phasevarion.

Results

Phase-variable expression of modM3, mediated by variation in length of a 5′-(CAAC)_n-3′ tetranucleotide repeat tract in the open reading frame was demonstrated in M. catarrhalis strain CCRI-195ME with GeneScan fragment length analysis and western immunoblot. We determined that ModM3 is an active N6-adenine methyltransferase that methylates the sequence 5′-AC^m6ATC-3′. Methylation was detected at all 4446 5′-ACATC-3′ sites in the genome when ModM3 is expressed. RNASeq analysis identified 31 genes that are differentially expressed between modM3 ON and OFF variants, including five genes that are involved in the response to oxidative and nitrosative stress, with potential roles in biofilm formation and survival in anaerobic environments. An in vivo chinchilla (Chinchilla lanigera) model of otitis media demonstrated that transbullar challenge with the modM3 OFF variant resulted in an increased middle ear bacterial load compared to a modM3 ON variant. In addition, co-infection experiments with NTHi and M. catarrhalis modM3 ON or modM3 OFF variants revealed that phase variation of modM3 altered survival of NTHi in the middle ear during early and late stage infection.

Conclusions

Phase variation of ModM3 epigenetically regulates the expression of a phasevarion containing multiple genes that are potentially important in the progression of otitis media.

Pneumococcal conjugate vaccines for preventing acute otitis media in children

BACKGROUND

Prior to introducing pneumococcal conjugate vaccines (PCVs), Streptococcus pneumoniae was most commonly isolated from middle ear fluid of children with acute otitis media (AOM). Reducing nasopharyngeal colonisation of this bacterium by PCVs may lead to a decline in AOM. The effects of PCVs deserve ongoing monitoring since studies from the post-PCV era report a shift in causative otopathogens towards non-vaccine serotypes and other bacteria. This updated Cochrane Review was first published in 2002 and updated in 2004, 2009, and 2014. The review title was changed (to include the population, i.e. children) for this update.

OBJECTIVES

To assess the effect of PCVs in preventing AOM in children up to 12 years of age.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, Web of Science, and trials registers (ClinicalTrials.gov and WHO ICTRP) to 29 March 2019.

SELECTION CRITERIA

Randomised controlled trials of PCV versus placebo or control vaccine.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. The primary outcomes were frequency of all-cause AOM and adverse effects. Secondary outcomes included frequency of pneumococcal AOM and frequency of recurrent AOM (defined as three or more AOM episodes in six months or four or more in one year). We used GRADE to assess the quality of the evidence.

MAIN RESULTS

We included 14 publications of 11 trials (60,733 children, range 74 to 37,868 per trial) of 7- to 11-valent PCVs versus control vaccines (meningococcus type C vaccine in three trials, and hepatitis A or B vaccine in eight trials). We included two additional trials for this update. We did not find any relevant trials with the newer 13-valent PCV. Most studies were funded by pharmaceutical companies. Overall, risk of bias was low. In seven trials (59,415 children) PCVs were administered in early infancy, while four trials (1318 children) included children aged one year and over who were either healthy or had a history of respiratory illness. There was considerable clinical heterogeneity across studies, therefore we did not perform meta-analyses.Adverse eventsNine trials reported on adverse effects (77,389 children; high-quality evidence). Mild local reactions and fever were common in both groups, and occurred more frequently in PCV than in control vaccine groups: redness (< 2.5 cm): 5% to 20% versus 0% to 16%; swelling (< 2.5 cm): 5% to 12% versus 0% to 8%; and fever (< 39 °C): 15% to 44% versus 8% to 25%. More severe redness (> 2.5 cm), swelling (> 2.5 cm), and fever (> 39 °C) occurred less frequently (0% to 0.9%, 0.1% to 1.3%, and 0.4% to 2.5%, respectively in children receiving PCV) and did not differ significantly between PCV and control vaccine groups. Pain or tenderness, or both was reported more frequently in PCV than in control vaccine groups: 3% to 38% versus 0% to 8%. Serious adverse events judged causally related to vaccination were rare and did not differ significantly between groups, and no fatal serious adverse event judged causally related to vaccination was reported.PCV administered in early infancyPCV7The effect of a licenced 7-valent PCV with CRM197 as carrier protein (CRM197-PCV7) on all-cause AOM varied from -5% (95% confidence interval (CI) -25% to 12%) relative risk reduction (RRR) in high-risk infants (1 trial; 944 children; moderate-quality evidence) to 6% (95% CI -4% to 16%; 1 trial; 1662 children) and 6% (95% CI 4% to 9%; 1 trial; 37,868 children) RRR in low-risk infants (high-quality evidence). PCV7 with the outer membrane protein complex of Neisseria meningitidis serogroup B as carrier protein (OMPC-PCV7), was not associated with a reduction in all-cause AOM (RRR -1%, 95% CI -12% to 10%; 1 trial; 1666 children; high-quality evidence).CRM197-PCV7 and OMPC-PCV7 were associated with 20% (95% CI 7% to 31%) and 25% (95% CI 11% to 37%) RRR in pneumococcal AOM, respectively (2 trials; 3328 children; high-quality evidence) and CRM197-PCV7 with 9% (95% CI -12% to 27%) to 10% (95% CI 7% to 13%) RRR in recurrent AOM (2 trials; 39,530 children; high-quality evidence).PHiD-CV10/11The effect of a licenced 10-valent PCV conjugated to protein D, a surface lipoprotein of Haemophilus influenzae, (PHiD-CV10) on all-cause AOM varied from 6% (95% CI -6% to 17%; 1 trial; 5095 children) to 15% (95% CI -1% to 28%; 1 trial; 7359 children) RRR in healthy infants (moderate-quality evidence). PHiD-CV11 was associated with 34% (95% CI 21% to 44%) RRR in all-cause AOM (1 trial; 4968 children; high-quality evidence).PHiD-CV10 and PHiD-CV11 were associated with 53% (95% CI 16% to 74%) and 52% (95% CI 37% to 63%) RRR in pneumococcal AOM (2 trials; 12,327 children; high-quality evidence) and PHiD-CV11 with 56% (95% CI -2% to 80%) RRR in recurrent AOM (1 trial; 4968 children; moderate-quality evidence).PCV administered at later agePCV7We found no evidence of a beneficial effect on all-cause AOM of administering CRM197-PCV7 in children aged 1 to 7 years with a history of respiratory illness or frequent AOM (2 trials; 457 children; high-quality evidence) and CRM197-PCV7 combined with a trivalent influenza vaccine in children aged 18 to 72 months with a history of respiratory tract infections (1 trial; 597 children; high-quality evidence).CRM197-PCV9In 1 trial including 264 healthy day-care attendees aged 1 to 3 years, CRM197-PCV9 was associated with 17% (95% CI -2% to 33%) RRR in parent-reported all-cause OM (low-quality evidence).

AUTHORS' CONCLUSIONS

Administration of the licenced CRM197-PCV7 and PHiD-CV10 during early infancy is associated with large relative risk reductions in pneumococcal AOM. However, the effects of these vaccines on all-cause AOM is far more uncertain. We found no evidence of a beneficial effect on all-cause AOM of administering PCVs in high-risk infants, after early infancy (i.e. in children one year and above), and in older children with a history of respiratory illness. Compared to control vaccines, PCVs were associated with an increase in mild local reactions (redness, swelling), fever, and pain and/or tenderness. We found no evidence of a difference in more severe local reactions, fever, or serious adverse events judged causally related to vaccination.

Effect of a participatory intervention in women's self-help groups for the prevention of chronic suppurative otitis media in their children in Jumla Nepal: a cluster-randomised trial

Background

Chronic suppurative otitis media (CSOM) causes preventable deafness and disproportionately affects children living in poverty. Our hypothesis was that health promotion in women’s groups would increase their knowledge, attitudes and practices (KAP) regarding ear disease and reduce the prevalence of CSOM in their children.

Methods

We did a cluster randomised trial in two village development committees (VDCs) in Jumla, Nepal. In July 2014, 30 women’s groups were randomly allocated to intervention or control, stratified by VDC and distance to the road. The intervention groups participated in three sessions of health promotion using the WHO Hearing and Ear Care Training Resource Basic Level. The primary outcome was women’s KAP score and the secondary outcome was prevalence of CSOM in their children at 12 month follow-up. Analyses were by intention to treat. Participants and the research team were not masked to allocation.

Results

In June and July 2014 we recruited 508 women and 937 of their children. 12 months later there was no difference in the women’s KAP score (mean difference 0.14, 95% CI − 0.1 to 0.38, P = 0.25) or the prevalence of CSOM in their children (OR 1.10, 95%CI 0.62 to 1.84, P = 0.75) between intervention and control groups. However, overall, there was a significant improvement in the KAP score (mean difference − 0.51, 95% CI − 0.71,to − 0.31, P < 0.0001) and in the prevalence of CSOM from baseline 11.2% to follow-up 7.1% (P < 0.0001).

Conclusions

Health promotion in women’s groups did not improve maternal KAP or reduce prevalence of CSOM. Over time there was a significant improvement in women’s KAP score and reduction in the prevalence of CSOM which may be attributable to our presence in the community offering treatment to affected children, talking to their parents and providing ciprofloxacin drops to the local health posts. More research is needed in low resource settings to test our findings.

Trial registration

Australia and New Zealand Clinical Trial Registry 12,614,000,231,640; Date of registration: 5.3.2014: Prospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12887-019-1539-y) contains supplementary material, which is available to authorized users.

Effect of a pneumococcal whole cell vaccine on influenza A-induced pneumococcal otitis media in infant mice

The pneumococcus remains a common cause of otitis media (OM) despite the widespread introduction of pneumococcal conjugate vaccines. In mice, a pneumococcal whole cell vaccine (WCV) induces serotype-independent protection against pneumococcal colonisation and invasive disease via T_H17- and antibody-mediated immunity, respectively. We investigated the effect of WCV on influenza A-induced pneumococcal OM in an infant mouse model. C57BL/6 mice were immunised subcutaneously with a single dose of WCV or adjuvant at 6 days of age, infected with pneumococci (EF3030 [serotype 19F] or PMP1106 [16F]) at 12 days of age, and given influenza A virus (A/Udorn/72/307 [H3N2], IAV) at 18 days of age to induce pneumococcal OM. Pneumococcal density in middle ear and nasopharyngeal tissues was determined 6 and 12 days post-virus. Experiments were repeated in antibody (B6.μMT^-/-)- and CD4⁺ T-cell-deficient mice to investigate the immune responses involved. A single dose of WCV did not prevent the development of pneumococcal OM, nor accelerate pneumococcal clearance compared with mice receiving adjuvant alone. However, WCV reduced the density of EF3030 in the middle ear at 6 days post-viral infection (p = 0.022), and the density of both isolates in the nasopharynx at 12 days post-viral infection (EF3030, p = 0.035; PMP1106, p = 0.011), compared with adjuvant alone. The reduction in density in the middle ear required antibodies and CD4⁺ T cells: WCV did not reduce EF3030 middle ear density in B6.μMT^-/- mice (p = 0.35) nor in wild-type mice given anti-CD4 monoclonal antibody before and after IAV inoculation (p = 0.91); and WCV-immunised CD4⁺ T cell-deficient GK1.5 mice had higher levels of EF3030 in the middle ear than their adjuvant-immunised counterparts (p = 0.044). A single subcutaneous dose of WCV reduced pneumococcal density in the middle ears of co-infected mice in one of two strains tested, but did not prevent OM from occurring in this animal model.

Acute otitis media in infants younger than two months of age: Epidemiologic and microbiologic characteristics in the era of pneumococcal conjugate vaccines

OBJECTIVES

To evaluate the epidemiology, microbiology, Streptococcus pneumoniae serotypes distribution and serious bacterial infections (SBIs) occurrence in infants <2 months of age with tympanocentesis-documented acute otitis media (AOM), before and after the introduction of pneumococcal conjugate vaccines (PCVs).

METHODS

The medical records of all hospitalized infants with AOM who underwent tympanocentesis during 2005-2014 were reviewed.

RESULTS

Of the 303 infants with AOM who were diagnosed by an ENT specialist, 182 underwent tympanocentesis, 92 during 2005-2009 (prevaccine period) and 90 during 2010-2014 (postvaccine period). Streptococcus pneumoniae and nontypeable Hemophilus influenzae were isolated in 46/92 (50%) and 37/92 (40.2%) patients during 2005-2009 and decreased to 27/90 (30%) and 21/90 (23.3%). Respectively, during 2010-2014 (P = 0.006 and P = 0.001). The proportion of culture-negative patients increased from 18/92 (19.6%) during 2005-2009 to 32/90 (35.6%) during 2010-2014 (P = 0.02). There were only 6 (3.3%) patients <2 weeks of age. The most common S. pneumoniae vaccine serotypes isolated during 2005-2009 were 5, 3, 1, 19F and 14 (15.2%, 13.0%, 10.9%, 6.5%, and 4.3%, respectively) and 3, 5, 1, 14 and 19A (22.2%, 11.1%, 7.4%, 7.4%, and 7.4%, respectively) during 2010-2014. The proportion of culture-positive patients decreased during 2013-2014 compared with 2011-2012 (7/18, 38.9% vs. 40/54, 74.1%, P = 0.007). Serotypes 1 and 5 were not isolated during 2013-2014 and serotype 19A was not isolated during 2011-2014. . SBIs were recorded in 23/182 (12.64%) patients and urinary tract infections represented 19/23 (82.61%) of them (Escherichia coli isolated in 12, 63.2%).

CONCLUSIONS

The overall number of AOM cases needing tympanocentesis seen at the PER and the proportion of S. pneumoniae and nontypeable H. influenzae-AOM decreased while the proportion of culture-negative AOM increased following the introduction of PCVs. SBIs associated with AOM were frequent and were represented mostly by urinary tract infections caused by pathogens unrelated to the etiologic agents of AOM.

Moraxella catarrhalis Restriction-Modification Systems Are Associated with Phylogenetic Lineage and Disease

Moraxella catarrhalis is a human-adapted pathogen, and a major cause of otitis media (OM) and exacerbations of chronic obstructive pulmonary disease. The species is comprised of two main phylogenetic lineages, RB1 and RB2/3. Restriction–modification (R-M) systems are among the few lineage-associated genes identified in other bacterial genera and have multiple functions including defense against foreign invading DNA, maintenance of speciation, and epigenetic regulation of gene expression. Here, we define the repertoire of R-M systems in 51 publicly available M. catarrhalis genomes and report their distribution among M. catarrhalis phylogenetic lineages. An association with phylogenetic lineage (RB1 or RB2/3) was observed for six R-M systems, which may contribute to the evolution of the lineages by restricting DNA transformation. In addition, we observed a relationship between a mutually exclusive Type I R-M system and a Type III R-M system at a single locus conserved throughout a geographically and clinically diverse set of M. catarrhalis isolates. The Type III R-M system at this locus contains the phase-variable Type III DNA methyltransferase, modM, which controls a phasevarion (phase-variable regulon). We observed an association between modM presence and OM-associated middle ear isolates, indicating a potential role for ModM-mediated epigenetic regulation in OM pathobiology.

Virulence determinants of Moraxella catarrhalis: distribution and considerations for vaccine development

Moraxella catarrhalis is a human-restricted opportunistic bacterial pathogen of the respiratory mucosa. It frequently colonizes the nasopharynx asymptomatically, but is also an important causative agent of otitis media (OM) in children, and plays a significant role in acute exacerbations of chronic obstructive pulmonary disease (COPD) in adults. As the current treatment options for M. catarrhalis infection in OM and exacerbations of COPD are often ineffective, the development of an efficacious vaccine is warranted. However, no vaccine candidates for M. catarrhalis have progressed to clinical trials, and information regarding the distribution of M. catarrhalis virulence factors and vaccine candidates is inconsistent in the literature. It is largely unknown if virulence is associated with particular strains or subpopulations of M. catarrhalis, or if differences in clinical manifestation can be attributed to the heterogeneous expression of specific M. catarrhalis virulence factors in the circulating population. Further investigation of the distribution of M. catarrhalis virulence factors in the context of carriage and disease is required so that vaccine development may be targeted at relevant antigens that are conserved among disease-causing strains. The challenge of determining which of the proposed M. catarrhalis virulence factors are relevant to human disease is amplified by the lack of a standardized M. catarrhalis typing system to facilitate direct comparisons of worldwide isolates. Here we summarize and evaluate proposed relationships between M. catarrhalis subpopulations and specific virulence factors in the context of colonization and disease, as well as the current methods used to infer these associations.