Substantial reduction of antibiotic-non-susceptible pneumococcal otitis media following PCV7/PCV13 sequential introduction

Characterization of Streptococcus pneumoniae isolates obtained from the middle ear fluid of US children, 2011-2021

Introduction

Pneumococcal conjugate vaccines (PCVs), including higher valency vaccines such as PCV20, have the potential to reduce pediatric otitis media. We assessed serotype distribution, potential PCV coverage, and antimicrobial susceptibility of Streptococcus pneumoniae isolates cultured from middle ear fluid (MEF) of US children age ≤5 years.

Methods

S. pneumoniae isolates identified from US hospitals participating in the SENTRY Antimicrobial Surveillance program from 2011 to 2021 were included. Serotypes were determined by in silico analysis based on Pneumococcal Capsular Typing methodology. The percentage of isolates belonging to serotypes included in PCV13 (serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F), PCV15 (PCV13 plus 22F, 33F), and PCV20 (PCV13 plus, 8, 10A, 11A, 12F, 15B, 22F and 33F) was calculated. Antimicrobial susceptibility testing was performed by broth microdilution and interpreted using CLSI criteria. Nonsusceptibility was defined as isolates that were intermediate or resistant to a selected antimicrobial.

Results

Among the 199 S. pneumoniae isolates that were identified, 56.8% were from children age <2 years. Six serotypes accounted for around 60% of isolates: 35B (16.6%), 15B (14.6%), 15A (7.5%), 19A (7.5%), 19F (7.5%), and 3 (7.0%). Serotypes included in PCV13, PCV15, and PCV20 accounted for 23.1%, 30.2%, and 54.8% of isolates, respectively. Overall, 45.2% of isolates were penicillin non-susceptible, and 13.6% were MDR, of which 48% were serotype 19A. Seven serotypes (19A, 15A, 15B, 15C, 23A, 33F, and 35B) accounted for the majority of non-susceptible isolates.

Discussion

PCVs, particularly PCV20, may prevent a substantial fraction of S. pneumoniae otitis media (OM), including OM due to non-susceptible serotypes. The addition of serotypes 15A, 23A, and 35B would improve coverage against susceptible and non-susceptible pneumococcal OM.

ISOM 2023 Research Panel 5: Interventions- Vaccines and prevention, medical and surgical treatment, and impact of COVID-19 pandemic

OBJECTIVES

To identify and synthesize key research advances from the literature published between 2019 and 2023 on the advances in preventative measures, and medical and surgical treatment of uncomplicated otitis media (OM) including the impact of the COVID-19 pandemic on OM management.

DATA SOURCES

Medline (PubMed), Embase, and the Cochrane Library.

REVIEW METHODS

All relevant original articles published in English between June 2019 and February 2023 were identified. Studies related to guideline adherence, impact of treatment on immune response and/or microbiology, tympanoplasty, Eustachian tube balloon dilatation, mastoidectomy procedures, and those focusing on children with Down's syndrome or cleft palate were excluded.

MAIN FINDINGS

Of the 9280 unique records screened, 64 were eligible for inclusion; 23 studies related to medical treatment, 20 to vaccines, 13 to surgical treatment, 6 to prevention (excl. vaccines) and 2 to the impact of COVID-19 on OM management. The level of evidence was judged 2 in 11 studies (17.2 %) and 3 or 4 in the remaining 53 studies (82.8 %) mainly due to the observational design, study limitations or low sample sizes. Some important advances in OM management have been made in recent years. Video discharge instructions detailing the identification and management of pain and fever for parents of children with acute otitis media (AOM) was more effective than paper instructions in reducing symptomatology; compared to placebo, levofloxacin solution was more effective for treating chronic suppurative otitis media, whereas AOM recurrences during two years of follow-up did not differ between children with recurrent AOM who received tympanostomy tube (TT) insertion or medical management. Further, novel pneumococcal conjugate vaccines (PCV) schedules for preventing OM in Aboriginal children appeared ineffective, and a protein-based pneumococcal vaccine had no added value over PCV13 for preventing AOM in native American infants. During the COVID-19 pandemic, a decline in OM and TT case volumes and complications was observed.

IMPLICATION FOR PRACTICE AND FUTURE RESEARCH

Whether the observed impact of the COVID-19 pandemic on OM management extends to the post-pandemic era is uncertain. Furthermore, the impact of the pandemic on the conduct of urgently needed prospective methodologically rigorous interventional studies aimed at improving OM prevention and treatment remains to be elucidated since the current report consisted of studies predominantly conducted in the pre-pandemic era.

Acute otitis media in the first two months of life and the impact of pneumococcal conjugate vaccines: A retrospective cohort study

BACKGROUND

Information on pneumococcal vaccination's impact on the prevention of acute otitis media (AOM) at very young ages is limited.

OBJECTIVES

To define the trends in tympanocentesis-proven AOM incidence, clinical characteristics, microbiology, and antibiotic resistance in infants <2 months of age in southern Israel, before and after the sequential introduction of 7- and 13-valent PCVs.

METHODS

A retrospective population-based cohort study including children <2 months of age diagnosed with AOM at the pediatric emergency room between January 2005-Decmber 2009 (pre-vaccination group, group 1) and January 2013-July 2021 (post-PCV13 introduction, group 2).

RESULTS

160 patients were enrolled, 89 (55.6%) in group 1 and 71 (44.4%) in group 2. The mean incidence of AOM decreased from 1.2 cases/1000 live births for group 1 to 0.45 cases/1000 live births for group 2, P < 0.001.130 (81.25%) patients were hospitalized, with higher hospitalization rates in group 1 vs. group 2 (84/89, 94% vs. 46/71, 65%, P < 0.001). Hospitalization length was longer in group 1 vs. group 2 (4.07 ± 4.09 days vs. 2.70 ± 1.82 days, P = 0.021). Positive MEF cultures were reported in 94/160 (58.75%) patients, with a decrease in positivity rates between the 2 groups (71/89, 80% vs. 23/71, 32%, P < 0.001). S. pneumoniae was the most common pathogen (55/94, 58.5%); it was the most frequent pathogen isolated in group 1 (46/71, 65%), and the second most common pathogen in group 2 (9/23, 39%), P = 0.03. A significant increase was recorded in the percentages of patients with negative MEF cultures (from 21% to 68%, P < 0.001).

CONCLUSIONS

The introduction and implementation of PCV13 in southern Israel was associated with a decrease in AOM in children <2 months of age and of S. pneumoniae recovery in these patients and was accompanied by less admissions and shorter hospitalizations. An increase in the proportions of negative bacterial cultures from MEF was recorded during the study period.

The dynamic change of serotype distribution and antimicrobial resistance of pneumococcal isolates since PCV13 administration and COVID-19 control in Urumqi, China

Objective

This study aims to analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from children aged 8 days to 7 years in Urumqi, China, between 2014 to 2021, during which PCV13 was introduced in the private sector's immunization program and COVID-19 control was administrated in the last 2 years.

Methods

Serotypes of S. pneumoniae isolates were determined by Quellung reaction, and their susceptibility against 14 antimicrobials were tested. According to the start year of PCV13 administration (2017) and COVID-19 control (2020), the study period was divided into three stages: 2014-2015, 2018-2019, and 2020-2021.

Results

A total of 317 isolates were involved in this study. The most common serotypes were type 19F (34.4%), followed by 19A (15.8%), 23F (11.7%), 6B (11.4%), and 6A(5.0%). The coverage rate of both PCV13 and PCV15 was 83.0%. The coverage of PCV20 was a little higher at 85.2%. The resistance rate against penicillin was 28.6% according to the breakpoints of oral penicillin, which would reach up to 91.8% based on the breakpoints of parenteral penicillin for meningitis. The resistance rates to erythromycin, clindamycin, tetracycline, and sulfamethoxazole-trimethoprim were 95.9%, 90.2%, 88.9%, and 78.8%, respectively. The PCV13 isolate was more resistant to penicillin than the non-PCV13 ones. There was not any significant change found in the serotype distribution since the PCV13 introduction and the COVID-19 control. The resistance rate against oral penicillin slightly elevated to 34.5% in 2018-2019 from 30.7% in 2014-2015 and then decreased significantly to 18.1% in 2020-2021 (χ ² = 7.716, P < 0.05), while the resistance rate to ceftriaxone (non-meningitis) continuously declined from 16.0% in 2014-2015 to 1.4% in 2018-2019 and 0% in 2020-2021 (Fisher = 24.463, P < 0.01).

Conclusion

The common serotypes of S. pneumoniae isolated from children in Urumqi were types 19F, 19A, 23F, 6B, and 6A, which we found to have no marked change since the PCV13 introduction and the COVID-19 control However, the resistance rate to oral penicillin and ceftriaxone significantly declined in the COVID-19 control stage.

The broader impacts of otitis media and sequelae for informing economic evaluations of pneumococcal conjugate vaccines

INTRODUCTION

Otitis media (OM) is a common childhood infection. Pneumococcal conjugate vaccines (PCVs) prevent OM episodes, thereby reducing short- and long-term clinical, economic, humanistic, and societal consequences. Most economic evaluations of PCVs focus on direct health gains and cost savings from prevented acute episodes but do not fully account for the broader societal impacts of OM prevention.

AREAS COVERED

This review explores the broader burden of OM on children, caregivers, and society to better inform future economic evaluations of PCVs.

EXPERT OPINION

OM causes a substantial burden to society through long-term sequelae, productivity losses, reduced quality of life for children and caregivers, and contribution to antimicrobial resistance from inappropriate antibiotic use. The effect of PCVs on acute OM has been recognized globally, yet the broader impact has not been consistently quantified, studied, or communicated. Economic evaluations of PCVs must evolve to include broader effects for patients, caregivers, and society from OM prevention. Future PCVs with broader coverage may further reduce OM incidence and antimicrobial resistance, but optimal uptake will depend on increasing the recognition and use of novel frameworks that include broader benefits. Communicating the full value of PCVs to decision makers may result in wider access and positive societal returns.

Dynamic changes in otopathogens colonizing the nasopharynx and causing acute otitis media in children after 13-valent (PCV13) pneumococcal conjugate vaccination during 2015-2019

The otopathogens colonizing the nasopharynx (NP) and causing acute otitis media (AOM) have shown dynamic changes following introduction of pneumococcal conjugate vaccines. Five hundred eighty-nine children were prospectively enrolled, 2015-2019. Two thousand fifty-nine visits (1528 healthy, 393 AOM, and 138 AOM follow-up) were studied. Two thousand forty-two NP and 495 middle ear fluid (MEF) samples by tympanocentesis from 319 AOM cases were cultured for bacterial identification and antibiotic susceptibility. Streptococcus pneumoniae (Spn) isolates were serotyped by Quellung, and multi-locus sequence type (ST) determined by genomic analysis. Haemophilus influenzae (Hi) was the most common otopathogen cultured from MEF during AOM (34% in MEF) followed by Spn (24% in MEF), then Moraxella catarrhalis (Mcat) (15% in MEF). NP isolates during healthy visit were Mcat (39%), Spn (32%), Hi (12%). 48.6% of Hi isolates from MEF were beta-lactamase-producing. Spn non-susceptibility to penicillin and other antibiotics was high. The most common Spn serotypes associated with AOM (and colonizing the NP during healthy visits) were 35B, 23B, and 15B/C. ST558 and ST199 were the most common sequence types. During 2015-2019, Hi was the most common otopathogen cultured from MEF during AOM among young children. Pneumococcal AOM was most commonly caused by non-PCV13 serotypes of Spn, predominantly 35B, 23B, and 15B/C. Resistance to common antibiotics among Spn strains showed an increasing trend.