Influence of Pneumococcal Conjugate Vaccine on Acute Otitis Media with Severe Middle Ear Inflammation: A Retrospective Multicenter Study

Pediatric otitis media in Japan: A nationwide longitudinal study of the pre- and post-pneumococcal conjugate vaccine eras born in 2001 and 2010

BACKGROUND

Otitis media (OM) is a prevalent respiratory disease in children and poses significant public health challenges due to its impact on child health and economic burdens. However, there have no nationwide epidemiological studies conducted in Japan. This study investigates the epidemiological trends of OM in Japan, taking into account the impact of the 7-valent pneumococcal conjugate vaccine (PCV7) introduction.

METHOD

This study was retrospective cohort study using secondary data on the nationwide longitudinal birth cohort. This survey followed two cohorts born in 2001 (pre-PCV era) and 2010 (post-PCV era) until the age of 9. Every year, parents were surveyed about their children's health status, including occurrences of OM. The annual period prevalence and cumulative incidence of OM were assessed in this study, and the two cohorts were compared using a modified Poisson regression model adjusted environmental factors with the 2001 cohort as reference.

RESULT

The study included 47,015 children from the 2001 cohort and 38,554 from the 2010 cohort. Peak annual period prevalence of OM varied by era. Cumulative incidence was 13.8 % for the 2001 cohort and 18.5 % for the 2010 cohort by 1.5 years of age and 28.9 % and 33.3 %, respectively, by 3.5 years of age. In particular, from the fourth survey onward, covering ages 2.5-3.5 years, a shift was observed from an increased risk to a decreased risk of OM.

CONCLUSION

This nationwide longitudinal study emphasizes variations in OM epidemiology across Japan over time, with changes potentially influenced by the introduction of PCV7. In this study, due to the absence of individual PCV7 vaccination data, the effect of PCV7 was estimated based on the vaccination rate at the population level. The results suggest a notable decrease in the incidence of OM in later years, aligning with the increased uptake of PCV7.

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.

Effectiveness of Pneumococcal Vaccines on Otitis Media in Children: A Systematic Review

OBJECTIVES

We aimed to determine the effectiveness of pneumococcal vaccines on otitis media (OM) and acute otitis media (AOM) in children.

METHODS

We conducted a systematic search in databases PubMed (MEDLINE), Embase, Lilacs, and Web of Science. We included observational studies that evaluated any pneumococcal vaccine - including 7, 10, and 13-valent pneumococcal conjugate vaccines (PCV7, PCV10, and PCV13) and 23-valent polysaccharide vaccines (PPSV23) as the intervention, in children aged less than five years.

RESULTS

Out of the 2112 screened studies, 48 observational studies complied with the eligibility criteria and therefore were included in this review. Of the included studies, 30 (63%) were before-after, eleven (23%) cohort, six (13%) time series, and one (2%) case-control study designs. Vaccine effectiveness (VE) in preventing OM or AOM varied by vaccine type. In children under 24 months VE ranged from 8% and 42.7% (PCV7), 5.6% to 84% (PCV10) and 2.2% to 68% (PCV13). In children aged less than 60 months, VE ranged between 13.2% and 39% for PCV7, 11% to 39% for PCV10 (only children under 48 months), and 39% to 41% (PCV13).

CONCLUSIONS

Our results demonstrate significant effect of pneumococcal vaccination in decreasing OM or AOM in children under five years old in several countries supporting the public health value of introducing PCVs in national immunization programs.

Pneumococcal conjugate vaccines reduce myringotomy with tympanostomy tube insertion in young children in Japan

OBJECTIVE

Pneumococcal conjugate vaccines (PCVs) have been reported to reduce the incidence of myringotomy with tympanostomy tube insertion (MTTI) in children. However, little information is available focusing specific ages. We examined the prophylactic efficacy of PCVs on the onset of complex otitis media (ComOM) that requires MTTI.

METHOD

From 2011, the public support for PCV7 started with the usual four-dose schedule and an emergency schedule for 2- to 4-year-old children in Japan. PCV7 was replaced with PCV13 in 2013. We reviewed the nationwide database obtained from the JMDC Claims Database (https://www.jmdc.co.jp/en/) to examine the MTTI incidence during the era before and after PCV introduction (from 2008 to 2010 and from 2011 to 2017, respectively). Subjects were analyzed by stratified age groups (from 0 to 8 years old) and in subdivided groups of 6 months (from 0 to 35 months old). We compared the MTTI incidence between the groups for each age as well as between those for each calendar year.

RESULTS

A significant reduction in the MTTI incidence was detected in the 1-year-old children of the PCV era compared to those of the pre-PCV era. The reduction rates were more prominent in the 12-17 months group as compared to the 18-23 months group (PCV7 p = .005 and PCV13 p = .011, PCV7 p = .014 and PCV13 p = .153, respectively). The significant difference in the 1-year-old children continued in six of seven calendar years from 2011 to 2017, whereas no significant reduction was detected in children >3 years old.

CONCLUSIONS

The introduction of both PCV7 and PCV13 reduced MTTI incidences in children around 1 year old, and the effects were more prominent during the early half-periods. Our results support etiological evidence that pneumococcal infection in children aged 1 year and younger might play roles in the pathogenesis of ComOM that requires MTTI.

Improvement in the appropriate antimicrobial usage for treating pediatric acute otitis media in Japan: A descriptive study using nation-wide electronic medical record data

OBJECTIVES

We investigated changes in prescriptions for antimicrobial agents to treat children with acute otitis media (AOM).

METHODS

A descriptive study using an electronic medical record database. Of 199,896 patients enrolled between 2001 and 2019, a total of 10,797 were aged <16 years and had AOM as their first and primary disease (overall pediatric AOM cohort). In addition, 4786 patients with AOM without other comorbidities (pediatric AOM cohort) were included.

RESULTS

In the overall pediatric AOM cohort, the age distribution ranged from 11% to 23% for those younger than 2 years and from 66% to 77% for those younger than 6 years, with no change over time. In the pediatric AOM cohort, the antimicrobial prescription rate was 91% in 2001 but declined to 40% by 2019. Antimicrobial use increased from 0% to 75% for penicillins, whereas use of cephalosporins decreased from 84% to 10%. The prescription rate for acetaminophen alone increased from 33% to 58%. There were no differences in the incidence of adverse reactions among the prescribed antimicrobials.

CONCLUSIONS

Due to education efforts and promotion of the proper use of antimicrobials through means such as the Clinical practice guidelines for the diagnosis and management of acute otitis media in children (2006) and the Manual of Antimicrobial Stewardship (2016), a change in the use of antimicrobials occurred, leading to a trend to more proper use of these agents.

Alteration of payload in extracellular vesicles by crosstalk with mesenchymal stem cells from different origin

Background

The application of extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) requires customized materials to target disease or cell damage. We hypothesized that EVs exert different inflammatory effects on one recipient cell, although stem cells of different origins in humans have similar payloads.

Results

Here, the payload of EVs released by crosstalk between MSCs and human middle ear epithelial cells (HMEECs) extracted from adipose tissue, bone marrow and tonsils significantly increased the level of anti-inflammatory factors. EVs derived from the co-culture medium decreased TNF-, COX-2, IL-1, and IL-6 levels to approximately zero within 3h in HMEECs. Expression of miR-638 and amyloid- A4 precursor protein-binding family A member 2 was analyzed using microarrays and gene ontology analysis, respectively.

Conclusions

In conclusion, stem cells of different origins have different payloads through crosstalk with recipient-specific cells. Inducing specific factors in EVs by co-culture with MSCs could be valuable in regenerative medicine.

Graphical abstract

Changes in Otitis Media Episodes and Pressure Equalization Tube Insertions Among Young Children Following Introduction of the 13-Valent Pneumococcal Conjugate Vaccine: A Birth Cohort-based Study

BACKGROUND

The impact of 13-valent pneumococcal conjugate vaccine (PCV13) introduction on the occurrence of first and subsequent otitis media (OM) episodes in early childhood is unclear. We compared the risk of OM episodes among children age <2 years before and after PCV13 introduction, accounting for the dependence between OM episodes.

METHODS

We identified consecutive annual (July-June) cohorts of Tennessee Medicaid-enrolled children (2006-2014) from birth through age 2 years. We identified OM episodes using coded diagnoses (we classified diagnoses <21 days apart as the same episode). We modeled adjusted hazard ratios (aHRs) for OM comparing 7-valent pneumococcal conjugate vaccine (PCV7)-era (2006-2010) and PCV13-era (2011-2014) birth cohorts, accounting for risk factors and dependence between first and subsequent episodes. Secondary analyses examined pressure equalization tube (PET) insertions and compared the risk of recurrent OM (≥3 episodes in 6 months or ≥4 episodes in 12 months) between PCV7- and PCV13-era birth cohorts.

RESULTS

We observed 618 968 OM episodes and 24 875 PET insertions among 368 063 children. OM and PET insertion rates increased during the PCV7 years and declined after PCV13 introduction. OM and PET insertion risks were lower in the 2013-2014 cohort compared with the 2009-2010 cohort (aHRs [95% confidence interval], 0.92 [.91-.93] and 0.76 [.72-.80], respectively). PCV13 introduction was associated with declines in the risk of first, subsequent, and recurrent OM.

CONCLUSIONS

The transition from PCV7 to PCV13 was associated with a decline of OM among children aged <2 years due to a reduction in the risk of both the first and subsequent OM episodes.

Ten year public health impact of 13-valent pneumococcal conjugate vaccination in infants: A modelling analysis

Pneumococcal disease is a substantial contributor to illness and death in young children globally. The introduction of 7-valent pneumococcal conjugate vaccine (PCV7) in 2000 had a significant impact in preventing pneumococcal disease in both vaccinated children and unvaccinated individuals (through herd effect). A higher valent PCV13 replaced PCV7 in late 2009. This analysis was undertaken to assess how many cases and deaths have been averted over the last decade since PCV13 introduction. A model estimated the number of infants vaccinated annually with PCV13, as well as the number of cases and deaths of invasive pneumococcal disease, pneumococcal pneumonia, and acute otitis media cases averted. PCV13 vaccination was estimated to have prevented 175.2 million cases of all pneumococcal diseases and 624,904 deaths globally between 2010 and 2019. These results demonstrate the substantial public health impact of PCV13 and highlight the importance of increasing the global reach of PCV programs.

Clinical practice guidelines for the diagnosis and management of acute otitis media in children-2018 update

OBJECTIVE

"Clinical Practice Guidelines for the Diagnosis and Management of Acute Otitis Media in Children-2018 update (2018 Guidelines)" aim to provide appropriate recommendations about the diagnosis and management of children with acute otitis media (AOM), including recurrent acute otitis media (recurrent AOM), in children under 15 years of age. These evidence-based recommendations were created with the consensus of the subcommittee members, taking into consideration unique characteristics of bacteriology and antimicrobial susceptibilities of AOM pathogens in Japan, as well as global advances in vaccines.

METHODS

The subcommittee re-evaluated key clinical issues based on SCOPE (a master plan of the guidelines) and created clinical questions (CQ) about the diagnosis and management of AOM patients. A literature search of the publications from 2013 to 2016 were added to the Guidelines 2013, not only to assess the evidence on the effectiveness of vaccines, but also to provide up to date information of the bacteriology and antimicrobial susceptibilities of AOM causative pathogens in Japan.

RESULTS

We have proposed guidelines for disease severity-based management of AOM patients, after classifying AOM severity into mild, moderate, and severe, based on age, clinical manifestations, and otoscopic findings.

CONCLUSIONS

Precise otoscopic findings are essential for judging AOM severity, which can lead to appropriate management of AOM patients.

Updated Guidelines for the Management of Acute Otitis Media in Children by the Italian Society of Pediatrics: Prevention

BACKGROUND

In recent years, new information has been acquired regarding the diagnosis, treatment and prevention of acute otitis media (AOM). The Italian Pediatric Society, therefore, decided to issue an update to the Italian Pediatric Society guidelines published in 2010.

METHODS

The search was conducted on Pubmed, and only those studies regarding the pediatric age alone, in English or Italian, published between January 1, 2010 and December 31, 2018, were included. Each study included in the review was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology. The quality of the systematic reviews was evaluated using the A MeaSurement Tool to Assess systematic Reviews (AMSTAR) 2 appraisal tool. The guidelines were formulated using the GRADE methodology by a multidisciplinary panel of experts.

RESULTS

The importance of eliminating risk factors (passive smoking, environmental pollution, use of pacifier, obesity, limitation of day-care center attendance) and the promotion of breastfeeding and hygiene practices (nasal lavages) was confirmed. The importance of pneumococcal vaccination in the prevention of AOM was reiterated with regard to the prevention of both the first episode of AOM and recurrences. Grommets can be inserted in selected cases of recurrent AOM that did not respond to all other prevention strategies. Antibiotic prophylaxis is not recommended for the prevention of recurrent AOM, except in certain carefully selected cases. The use of complementary therapies, probiotics, xylitol and vitamin D is not recommended.

CONCLUSIONS

The prevention of episodes of AOM requires the elimination of risk factors and pneumococcal and influenza vaccination. The use of other products such as probiotics and vitamin D is not supported by adequate evidence.

Phosphorylcholine intranasal immunization with a 13-valent pneumococcal conjugate vaccine can boost immune response against Streptococcus pneumoniae

OBJECTIVE

This study aimed to investigate whether systemic immunization with a 13-valent pneumococcal conjugate vaccine (PCV13) followed by intranasal (IN) immunization with phosphorylcholine (PC) can boost immune response against Streptococcus pneumoniae.

MATERIALS AND METHODS

Two weeks after the intraperitoneal (IP) injection of PCV13, mice were divided into two groups (mice requiring another IP injection of PCV13 and mice requiring PC-keyhole limpet hemocyanin IN immunization in combination with cholera toxin as a mucosal adjuvant) to compare the magnitude of systemic and mucosal immune responses against S. pneumoniae and PC.

RESULTS

Serum immunoglobulin (Ig) G antibody titer against the vaccine strains of S. pneumoniae was similar between the PCV13 systemic immunization group and PC IN immunization group, while the serum IgG antibody titer against PC was significantly higher in the PC IN immunization group. PC-specific IgA antibody titer in the nasal lavage and PC-specific IgA-producing cell number in the nasal mucosa were also significantly higher in the PC IN immunization group. Induction of PC-specific IgA in the PC IN immunization group enhanced the clearance of bacteria from the middle ear.

CONCLUSION

Additional IN immunization with PC after PCV13 immunization, which is currently conducted under a periodic vaccination program, can produce a booster effect comparable to that achieved by additional systemic immunization as well as PC-specific mucosal immune response, thereby providing protection against S. pneumoniae serotypes not contained in PCV13.

Role of phosphorylcholine in Streptococcus pneumoniae and nontypeable Haemophilus influenzae adherence to epithelial cells

OBJECTIVE

Phosphorylcholine (PC) is a structural component of Streptococcus pneumoniae (Spn) and nontypeable Haemophilus influenzae (NTHi), and is known to be associated with adherence through the platelet activating factor receptor (PAF-R). Furthermore, high PC expression is considered to be involved in Spn and NTHi virulence. In this study, we examined the influence of PC expression on the adherence of Spn and NTHi to epithelial cells in order to clarify the potential effectiveness of a vaccine targeting PC.

METHODS

Twenty-seven strains of Spn and twenty-two strains of NTHi were used, cultured overnight, and PC expression was evaluated by fluorescence activated cell sorting; the strains were divided into two groups: PC low expression (PC-low) and PC high expression (PC-high) groups. Bacterial adherence was then examined using Detroit 562 cells and BALB/c mice. Bacterial invasion was then examined in Detroit 562 cells.

RESULTS

The adherence of Spn and NTHi and invasion of NTHi in the PC-high group was significantly reduced by pretreatment with a monoclonal anti-PC antibody (TEPC-15), PAF-R antagonist (ABT-491), and PC-keyhole limpet hemocyanin (PC-KLH). However, such findings were not observed in the PC-low group.

CONCLUSION

The present study suggests that PC is involved in the mucosal adhesion of Spn and NTHi, and the mucosal invasion of NTHi with PC-high strains, but not PC-low strains. These results suggest that a PC-targeting mucosal vaccine only affects PC-high Spn and NTHi strains and does not disturb commensal bacterial flora in the upper respiratory tract, which comprises nonpathogenic PC-low bacteria.