Cost-Effectiveness of 20-Valent Pneumococcal Conjugate Vaccine Among US Children with Underlying Medical Conditions

INTRODUCTION

A 20-valent pneumococcal conjugate vaccine (PCV20) was recently recommended for use among US children. We evaluated the cost-effectiveness of PCV20 among children aged 6 years with chronic medical conditions (CMC+) and children aged 6 years with immunocompromising conditions (IC) versus one and two doses of 23-valent pneumococcal polysaccharide vaccine (PPSV23), respectively.

METHODS

A probabilistic model was employed to depict 10-year risk of clinical outcomes and economic costs of pneumococcal disease, reduction in life years from premature death, and expected impact of vaccination among one cohort of children with CMC+ and IC aged 6 years. Vaccine uptake was assumed to be 20% for both PCV20 and PPSV23. Cost per quality-adjusted life year (QALY) gained was evaluated from the US societal and healthcare system perspectives; deterministic and probabilistic sensitivity analyses (DSA/PSA) were also conducted.

RESULTS

Among the 226,817 children with CMC+ aged 6 years in the US, use of PCV20 (in lieu of PPSV23) was projected to reduce the number cases of pneumococcal disease by 5203 cases, medical costs by US$8.7 million, and nonmedical costs by US$6.2 million. PCV20 was the dominant strategy versus PPSV23 from both the healthcare and societal perspectives. In the PSA, 99.9% of the 1000 simulations yielded a finding of dominance for PCV20. Findings in analyses of children with IC aged 6 years in the USA were comparable (i.e., PCV20 was the dominant vaccination strategy). Scenario analyses showed that increasing PCV20 uptake to 100% could potentially prevent > 22,000 additional cases of pneumococcal disease and further reduce medical and nonmedical costs by US$70.0 million among children with CMC+ and IC.

CONCLUSIONS

Use of PCV20 among young children with CMC+ and IC in the USA would reduce the clinical burden of pneumococcal disease and yield overall cost savings from both the US healthcare system and societal perspectives. Higher PCV20 uptake could further reduce the number of pneumococcal disease cases in this population.

Cost-effectiveness of 20-valent pneumococcal conjugate vaccine in US infants

BACKGROUND

As of June 2023, two pneumococcal conjugate vaccines, 20- (PCV20) and 15- (PCV15) valent formulations, are recommended for US infants under a 3 + 1 schedule. This study evaluated the health and economic impact of vaccinating US infants with a new expanded valency PCV20 formulation.

METHODS

A population-based, multi cohort, decision-analytic Markov model was developed to estimate the public health impact and cost-effectiveness of PCV20 from both societal and healthcare system perspectives over 10 years. Epidemiological data were based on published studies and unpublished Active Bacterial Core Surveillance System (ABCs) data. Vaccine effectiveness was based on PCV13 effectiveness and PCV7 efficacy studies. Indirect impact was based on observational studies. Costs and disutilities were based on published data. PCV20 was compared to both PCV13 and PCV15 in separate scenarios.

RESULTS

Replacing PCV13 with PCV20 in infants has the potential to avert over 55,000 invasive pneumococcal disease (IPD) cases, 2.5 million pneumonia cases, 5.4 million otitis media (OM) cases, and 19,000 deaths across all ages over a 10-year time horizon, corresponding to net gains of 515,000 life years and 271,000 QALYs. Acquisition costs of PCV20 were offset by monetary savings from averted cases resulting in net savings of $20.6 billion. The same trend was observed when comparing PCV20 versus PCV15, with a net gain of 146,000 QALYs and $9.9 billion in net savings. A large proportion of the avoided costs and cases were attributable to indirect effects in unvaccinated adults and elderly. From a health-care perspective, PCV20 was also the dominant strategy compared to both PCV13 and PCV15.

CONCLUSIONS

Infant vaccination with PCV20 is estimated to further reduce pneumococcal disease and associated healthcare system and societal costs compared to both PCV13 and PCV15.

Cost-effectiveness and impact on infections and associated antimicrobial resistance of 20-valent pneumococcal conjugate vaccine in US children previously immunized with PCV13

AIM

The US Food and Drug Administration approved the 20-valent pneumococcal conjugate vaccine (PCV20) to prevent pneumococcal disease. In the context of routine PCV20 vaccination, we evaluated the cost-effectiveness and public health and economic impact of a PCV20 catch-up program and estimated the number of antibiotic prescriptions and antibiotic-resistant infections averted.

MATERIALS AND METHODS

A population-based, multi-cohort, decision-analytic Markov model was developed using parameters consistent with previous PCV20 cost-effectiveness analyses. In the intervention arm, children aged 14-59 months who previously completed PCV13 vaccination received a supplemental dose of PCV20. In the comparator arm, no catch-up PCV20 dose was given. The direct and indirect benefits of vaccination were captured over a 10-year time horizon.

RESULTS

A PCV20 catch-up program would prevent 5,469 invasive pneumococcal disease cases, 50,286 hospitalized pneumonia cases, 218,240 outpatient pneumonia cases, 582,302 otitis media cases, and 1,800 deaths, representing a net gain of 30,014 life years and 55,583 quality-adjusted life years. Furthermore, 720,938 antibiotic prescriptions and 256,889 antibiotic-resistant infections would be averted. A catch-up program would result in cost savings of $800 million. These results were robust to sensitivity and scenario analyses.

CONCLUSIONS

A PCV20 catch-up program could prevent pneumococcal infections, antibiotic prescriptions, and antimicrobial-resistant infections and would be cost-saving in the US.

Burden of Lower Respiratory Tract Infections Preventable by Adult Immunization With 15- and 20-Valent Pneumococcal Conjugate Vaccines in the United States

BACKGROUND

Updated recommendations of the US Advisory Committee on Immunization Practices indicate that all adults aged ≥65 years and adults aged <65 years with comorbid conditions should receive 15- and 20-valent pneumococcal conjugate vaccines (PCV15/20). We aimed to assess the potential impact of these recommendations on the burden of lower respiratory tract infections (LRTIs) among adults.

METHODS

We estimated the incidence of LRTI cases and associated hospital admissions among enrollees of Kaiser Permanente Southern California from 2016 through 2019. We used a counterfactual inference framework to estimate excess LRTI-associated risk of death up to 180 days after diagnosis. We used prior estimates of PCV13 effectiveness against LRTI to model potential direct effects of PCV15/20 by age group and risk status.

RESULTS

Use of PCV15 and PCV20, respectively, could prevent 89.3 (95% confidence interval, 41.3-131.8) and 108.6 (50.4-159.1) medically attended LRTI cases; 21.9 (10.1-32.0) and 26.6 (12.4-38.7) hospitalized LRTI cases; and 7.1 (3.3-10.5) and 8.7 (4.0-12.7) excess LRTI-associated deaths, each per 10 000 person-years. Among at-risk adults aged <65 years, use of PCV15 and PCV20 could prevent 85.7 (39.6-131.5) and 102.7 (47.8-156.7) medically attended LRTI cases per 10 000 person-years; 5.1 (2.4-8.6) and 6.2 (2.8-10.2) LRTI hospitalizations per 10 000 person-years, and 0.9 (0.4-1.4) and 1.1 (0.5-1.7) excess LRTI-associated deaths per 10 000 person-years.

CONCLUSIONS

Our findings suggest recent recommendations, including PCV15/20 within adult pneumococcal vaccine series, may substantially reduce LRTI burden.

Persistence of Pneumococcal Carriage among Older Adults in the Community despite COVID-19 Mitigation Measures

Reported rates of invasive pneumococcal disease were markedly lower than normal during the 2020/2021 winter in the Northern Hemisphere, the first year after the start of the COVID-19 pandemic. However, little is known about rates of carriage of pneumococcus among adults during this period. Between October 2020-August 2021, couples in the Greater New Haven Area, USA, were enrolled if both individuals were aged 60 years and above and did not have any individuals under the age of 60 years living in the household. Saliva samples and questionnaires regarding social activities and contacts and medical history were obtained every 2 weeks for a period of 10 weeks. Following culture-enrichment, extracted DNA was tested using qPCR for pneumococcus-specific sequences piaB and lytA. Individuals were considered positive for pneumococcal carriage when Ct values for piaB were ≤40. Results. We collected 567 saliva samples from 95 individuals (47 household pairs and 1 singleton). Of those, 7.1% of samples tested positive for pneumococcus, representing 22/95 (23.2%) individuals and 16/48 (33.3%) households. Study participants attended few social events during this period. However, many participants continued to have regular contact with children. Individuals who had regular contact with preschool and school-aged children (i.e., 2 to 9 year olds) had a higher prevalence of carriage (15.9% versus 5.4%). Despite COVID-19-related disruptions, a large proportion of older adults continued to carry pneumococcus. Prevalence was particularly high among those who had contact with school-aged children, but carriage was not limited to this group. IMPORTANCE Carriage of Streptococcus pneumoniae (pneumococcus) in the upper respiratory tract is considered a prerequisite to invasive pneumococcal disease. During the first year of the COVID-19 pandemic, markedly lower rates of invasive pneumococcal disease were reported worldwide. Despite this, by testing saliva samples with PCR, we found that older adults continued to carry pneumococcus at pre-pandemic levels. Importantly, this study was conducted during a period when transmission mitigation measures related to the COVID-19 pandemic were in place. However, our observations are in line with reports from Israel and Belgium where carriage was also found to persist in children. In line with this, we observed that carriage prevalence was particularly high among the older adults in our study who maintained contact with school-aged children.

576. Burden of Pneumococcal Disease Due to Serotypes Covered by the 13-Valent and New Higher-Valent Pneumococcal Conjugate Vaccines in All Children and Children at Risk in the United States

Background

Routine vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) in infants along with a catch-up option with PCV13/PPSV23 in children with underlying medical conditions (UMC) have considerably reduced invasive pneumococcal disease (IPD) and non-invasive pneumococcal disease (PD), including community acquired pneumonia (CAP) and acute otitis media (AOM), in the United State (US). However, a rise in IPD and non-invasive PD caused by non-PCV13 serotypes has been observed. A 15-valent PCV (PCV15) and 20-valent PCV (PCV20), containing additional serotypes to PCV13, are anticipated for children soon. The objective of the study was to estimate the annual cases, deaths, and economic burden of disease attributable to PCV13, PCV15, and PCV20 serotypes in children < 18 years old overall and those with UMC in the US.

Methods

Estimated annual cases, deaths and direct medical costs associated with PD caused by PCV13, PCV15 and PCV20 serotypes were calculated based on published incidence rates of IPD, CAP, and AOM, along with age-group specific serotype coverage, case fatality rates, and disease-related costs (Table 1). The PD burden in those with UMC were extrapolated based on incidence rate ratios of those with UMC vs. those without UMC. The results were reported for 0-17 years and were further stratified into 2 age groups: 0-4 and 5-17 years. Table 1:

Detection of pneumococcus during hospitalization for SARS-CoV-2

Background

Infections with respiratory viruses [e.g. influenza and respiratory syncytial virus (RSV)] can increase the risk of severe pneumococcal infections. Likewise, pneumococcal coinfection is associated with poorer outcomes in viral respiratory infection. However, there are limited data describing the frequency of pneumococcus and SARS-CoV-2 coinfection and the role of coinfection in influencing COVID-19 severity. We, therefore, investigated the detection of pneumococcus in COVID-19 inpatients during the early pandemic period.

Methods

The study included patients aged 18 years and older, admitted to the Yale-New Haven Hospital who were symptomatic for respiratory infection and tested positive for SARS-CoV-2 during March-August 2020. Patients were tested for pneumococcus through culture-enrichment of saliva followed by RT-qPCR (to identify carriage) and serotype-specific urine antigen detection (UAD) assays (to identify presumed lower respiratory tract pneumococcal disease).

Results

Among 148 subjects, the median age was 65 years; 54.7% were male; 50.7% had an ICU stay; 64.9% received antibiotics; and 14.9% died while admitted. Pneumococcal carriage was detected in 3/96 (3.1%) individuals tested by saliva RT-qPCR. Additionally, pneumococcus was detected in 14/127 (11.0%) individuals tested by UAD, and more commonly in severe than moderate COVID-19 [OR: 2.20; 95% CI: (0.72, 7.48)]; however, the numbers were small with a high degree of uncertainty. None of the UAD-positive individuals died.

Conclusions

Pneumococcal lower respiratory tract infection (LRTI), as detected by positive UAD, occurred in patients hospitalized with COVID-19. Moreover, pneumococcal LRTI was more common in those with more serious COVID-19 outcomes. Future studies should assess how pneumococcus and SARS-CoV-2 interact to influence COVID-19 severity in hospitalized patients.

PCV13 Pediatric Routine Schedule Completion and Adherence Before and During the COVID-19 Pandemic in the United States

Introduction

A 13-valent pneumococcal conjugate vaccine (PCV13) was licensed to protect against emerging Streptococcus pneumoniae serotypes. Healthcare services, including routine childhood immunizations, were disrupted as a result of coronavirus disease 2019 (COVID-19). This study compared PCV13 routine vaccination completion and adherence among US infants before and during the COVID-19 pandemic and the relationship between primary and booster dose completion and adherence.

Methods

Retrospective data from Optum’s de-identified Clinformatics^® Data Mart were used to create three cohorts using data collected between January 2017 and December 2020: cohort 1 (C1), pre-COVID; cohort 2 (C2), cross-COVID; and cohort 3 (C3), during COVID. Study endpoints were completion and adherence to the primary PCV13 series (analyzed using univariate logistic regression) and completion of and adherence to the booster dose (analyzed descriptively).

Results

The analysis included 142,853 infants in C1, 27,211 infants in C2, and 53,306 infants in C3. Among infants with at least 8 months of follow-up from birth, three-primary-dose completion (receipt of all three doses within 8 months after birth) and adherence (receipt of doses at recommended times) were significantly higher before (C1 and C2) versus during (C3) COVID-19 (odds ratio [OR] 1.12 [95% confidence interval [CI] 1.07, 1.16] and OR 1.10 [95% CI 1.05, 1.15], respectively). A significantly higher percentage of infants received a booster dose before versus during COVID-19 (83.2% vs. 80.2%; OR 1.23; 95% CI 1.17, 1.29); similarly, booster dose adherence was higher before than during COVID-19 (51.2% vs. 47.4%; OR 1.17; 95% CI 1.13, 1.21). The odds of booster dose completion were 8.26 (95% CI 7.92, 8.60) and 7.90 (95% CI 7.14, 8.74) times as likely in infants who completed all three primary doses than in infants who did not complete primary doses before COVID-19 and during COVID-19, respectively.

Conclusions

PCV13 full completion was lower during the COVID-19 pandemic compared with pre-pandemic (79.0% vs. 77.1%).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-022-00699-5.

Burden of pneumococcal disease due to serotypes covered by the 13-valent and new higher-valent pneumococcal conjugate vaccines in the United States

The addition of pneumococcal conjugate vaccines (PCVs) to the United States (US) national immunization program led to significant reductions in incidence, mortality, and associated sequelae caused by pneumococcal disease (PD) in children and adults through direct and indirect protection. However, there remains clinical and economic burden due to PD caused by serotypes not included in the current 13-valent PCV (PCV13) formulation. To address this unmet need, 15-valent PCV (PCV15) and 20-valent PCV (PCV20), containing additional serotypes to PCV13, were recently approved in the US for adults and are anticipated for pediatrics in the near future. The study objective was to estimate the annual number of cases, deaths, and economic burden of PD due to serotypes included in PCV13, PCV15, and PCV20 for both US pediatric and adult populations. An Excel-based model was developed to calculate clinical and economic outcomes using published age-group specific serotype coverage; incidence of invasive PD, community-acquired pneumonia, and acute otitis media; case fatality rates; and disease-related costs. The results showed that across all age groups, the estimated annual PD cases and associated deaths covered by PCV13 serotypes were 914,199 and 4320, respectively. Compared with PCV13 serotypes, the additional 2 and 7 serotypes covered by PCV15 and PCV20 were attributed with 550,475 and 991,220 annual PD cases, as well as 1425 and 3226 annual deaths, respectively. This clinical burden translates into considerable economic costs ranging from $903 to $1,928 million USD that could be potentially addressed by PCV15 and PCV20. The additional serotypes included in PCV20 contribute substantially to the clinical and economic PD burden in the US pediatric and adult populations. Despite the success of the PCV13 pediatric national immunization program and increased adult uptake of PCV13 and 23-valent polysaccharide vaccine, broader PCV serotype coverage is needed across all ages to further reduce pneumococcal disease burden.

101. PCV13 Pediatric Vaccination Disparity and Impact Due to COVID-19 Pandemic in the US

Background

Existing disparities in vaccination rates across different social and demographic groups in the US may have been exacerbated during the Coronavirus Disease 2019 (COVID) pandemic, leaving some children at risk for vaccine-preventable diseases. This study examined sociodemographic and risk factors of PCV13 infant primary series vaccination completion, before and during COVID.

Methods

Retrospective data from the Optum’s de-identified Clinformatics Data Mart Database were used to create 3 cohorts: C1, Pre-COVID; C2, During COVID; C3, Cross-COVID (Figure 1). C1 and C3 (C1&3) were combined and compared with C2 for primary dosing completion before and during COVID according to infant/caregiver characteristics. Full completion (FC) was defined as receipt of 3 doses of PCV13 within 8 months of birth. Multivariable logistic regression was used to compare FC vs. partial completion or no vaccine. Descriptive analyses were used to compare FC before and during COVID within subgroups.

Figure 1: Study population and inclusion criteria

Results

A total of 132,183 and 16,522 infants with at least 8 months of follow up time were enrolled in C1&3 and C2, respectively. FC was significantly higher before COVID-19 (adjusted odds ratio = 1.12, 95% CI: 1.07-1.17). Adjusting for COVID, FC was significantly lower in infants who were Black, with co-morbidities or risk factors, living in households with &gt;1 children or no children, household annual income &lt; &99k, residing in a neighborhood with median education of high school or below, and whose primary caregiver was aged &lt;25 years (Table 1). Comparing FC before and during COVID, the % decline relative to pre-COVID was &gt; 2% among infants who were White, residing in the Mountain, New England or Pacific regions, in a household with 2 children, &gt;&100k annual income, employer-based insurance or HMO, and median neighborhood education of bachelor degree plus (Table 2).

Table 1. Multivariable binomial logistic regression results for PCV13 full primary dosing completion vs. not full completion (partial or no vaccine), N=144,799*

Conclusion

Health inequities in PCV13 primary series completion existed prior to COVID-19 and have remained during the pandemic. Our results, however, suggest that during the pandemic, groups traditionally considered to have better healthcare access (Whites, higher income, more education) had more impact on vaccine uptake. Further research is needed to confirm these trends as COVID mitigation measures subside.

Disclosures

Liping Huang, MD, MA, MS, Pfizer Inc (Employee) Jennifer L Nguyen, ScD, MPH, Pfizer Inc. (Employee) Johnna Perdrizet, MPH, Pfizer Inc (Employee) Tamuno Alfred, PhD, Pfizer Inc. (Employee) Adriano Arguedas, MD, Pfizer (Employee)

1179. PCV13 Pediatric Routine Schedule Completion and Adherence Before and During the COVID-19 Pandemic in the US

Background

Coronavirus Disease 2019 (COVID) mitigation measures may have unintended consequences, such as reduced or delayed access to routine immunizations. This study examined (1) PCV13 routine vaccination completion and adherence (C&A) among US infants before and during the COVID pandemic and (2) the relationship between primary dose C&A and booster dose C&A.

Methods

Retrospective data from the Optum’s de-identified Clinformatics Data Mart Database were used to create 3 cohorts: C1, Pre-COVID; C2, During COVID; C3, Cross-COVID (Figure 1). The completion was defined as number of PCV13 doses received within 8 months of birth, and the adherence was defined number of doses received at ACIP recommended time (@2, 4, 6 months, +/- 5 days). Univariable logistic regression was used to compare the odds of primary dose C&A in cohorts C1 and C3 vs C2 and descriptive analyses were used to explore primary dose C&A in relation to booster dose C&A.

Figure 1: Study population and inclusion criteria

Results

A total of 172,916, 70,049, and 34,854 infants were included in C1, C2, and C3. Among infants with &gt; 8 months of follow-up from birth (N=132,183 for C1&C3, 16,522 for C3), 3-primary dose completion was statistically significantly higher before COVID than during COVID (crude OR = 1.10, 95% CI: 1.06-1.15). The 3-primary dose adherence was also higher before COVID than during COVID (crude OR = 1.10, 95% CI: 1.05-1.15). Among infants with ≥2, 4 and 6 months of follow-up, adherence of each individual dose was consistently higher before COVID than during COVID (1st dose: OR = 1.03, 95% CI: 1.01–1.04; 2nd dose: OR = 1.04, 95% CI: 1.01 – 1.06; 3rd dose: OR = 1.12, 95% CI: 1.08 – 1.15) (Table 1). Booster dose completion was higher in infants who completed or adhered to 3 primary doses than infants who completed or adhered to only 1 or 2 primary doses (Figure 2, Overall) and booster dose C&A was generally higher before COVID than during COVID (Figure 2, Cohort 1 vs. Cohort 3).

Table 1. Comparison of completion and adherence of primary dosing series per-COVID vs. during-COVID era

Conclusion

These results indicated that PCV13 full completion was statistically lower during COVID, but the magnitude of the difference in infants was not extensive. Infants who completed or adhered to all three primary doses were more likely to complete or adhere to the booster dose. Further research is warranted as structured datasets mature to capture the full time span of COVID-19 mitigation measures.

Disclosures

Liping Huang, MD, MA, MS, Pfizer Inc (Employee) Jennifer L Nguyen, ScD, MPH, Pfizer Inc. (Employee) Johnna Perdrizet, MPH, Pfizer Inc (Employee) Tamuno Alfred, PhD, Pfizer Inc. (Employee) Adriano Arguedas, MD, Pfizer (Employee)

1321. Acquisition and Transmission of Streptococcus pneumoniae in Individuals Over the Age of 60 Years Residing in New Haven, CT, USA

Background

Despite the widespread use of pneumococcal conjugate vaccines, particularly in children, an important burden of pneumococcal disease remains in older adults. The acquisition and transmission rates of pneumococcus between older adults have not been well characterized.

Methods

Between October 2020-June 2021, couples living in the Greater New Haven Area were enrolled if both individuals were over the age of 60 years and did not have any individuals under the age of 60 years living in the household. Saliva samples and questionnaires regarding social patterns and medical history were obtained every 2 weeks for a period of 10 weeks. Following culture-enrichment, extracted DNA was tested using qPCR for pneumococcus-specific sequences piaB and lytA. Individuals were considered positive for pneumococcal carriage when qPCR Ct-values for piaB +/- lytA were less than 40.

Results

To date, we have collected 495 saliva samples from 95 individuals (48 households). Of 495 saliva samples, 31 (5.9%) have tested positive for pneumococcus by either piaB only (n=9) or both lytA and piaB (n=22). Of 95 individuals, 16 (16.8%) (representing 13, or 27.1% households) have tested positive at least once. Six of the 16 (37.5%) carriers tested positive at multiple timepoints, though none were colonized at all 6 time points over the course of the 10 weeks of study enrolment. For 3 of the 48 (6.3%) households, both members of the couple were identified as carriers, though not necessarily at the same sampling moment.

Conclusion

The preliminary findings of this longitudinal transmission model demonstrate evidence of pneumococcal acquisition among older adults measured by molecular tools. These transmission patterns and high rates of pneumococcal carriage in adults were observed during a period when the COVID-19 pandemic led to numerous preventative public health measures that may have reduced pneumococcal transmission (e.g., social distancing, mask wearing, bans on mass gatherings, restaurant closures, travel restrictions).

Disclosures

Anne Wyllie, PhD, Global Diagnostic Systems (Consultant)Pfizer (Advisor or Review Panel member, Research Grant or Support)PPS Health (Consultant)Tempus Labs, Inc (Research Grant or Support) Ronika Alexander-Parrish, RN, MAEd, Pfizer (Employee, Shareholder) Adriano Arguedas, MD, Pfizer (Employee) Bradford D. Gessner, MD, MPH, Pfizer Inc. (Employee) Daniel Weinberger, PhD, Affinivax (Consultant)Merck (Consultant, Grant/Research Support)Pfizer (Consultant, Grant/Research Support)

301. Detection of Pneumococcal Pneumonia During SARS-CoV-2 Infection

Background

Streptococcus pneumoniae (pneumococcus) is a common colonizer of the upper respiratory tract and can progress to cause invasive and mucosal disease. Additionally, infection with pneumococcus can complicate respiratory viral infections (influenza, respiratory syncytial virus, etc.) by exacerbating the initial disease. Limited data exist describing the potential relationship of SARS-CoV-2 infection with pneumococcus and the role of co-infection in influencing COVID-19 severity.

Methods

Inpatients and healthcare workers testing positive for SARS-CoV-2 during March-August 2020 were tested for pneumococcus through culture-enrichment of saliva followed by RT-qPCR (to identify carriage) and for inpatients only, serotype-specific urine antigen detection (UAD) assays (to identify pneumococcal pneumonia). A multinomial multivariate regression model was used to examine the relationship between pneumococcal detection and COVID-19 severity.

Results

Among the 126 subjects who tested positive for SARS-CoV-2, the median age was 62 years; 54.9% of subjects were male; 88.89% were inpatients; 23.5% had an ICU stay; and 13.5% died. Pneumococcus was detected in 17 subjects (13.5%) by any method, including 5 subjects (4.0%) by RT-qPCR and 12 subjects (13.6%) by UAD. Little to no bacterial growth was observed on 21/235 culture plates. Detection by UAD was associated with both moderate and severe COVID-19 disease while RT-qPCR detection in saliva was not associated with severity. None of the 12 individuals who were UAD-positive died.

Conclusion

Pneumococcal pneumonia (as determined by UAD) continues to occur during the ongoing pandemic and may be associated with more serious COVID-19 outcomes. Detection of pneumococcal carriage may be masked by high levels of antibiotic use. Future studies should better characterize the relationship between pneumococcus and SARS-CoV-2 across all disease severity levels.

Disclosures

Akiko Iwasaki, PhD, 4Bio (Consultant, Advisor or Review Panel member)Adaptive Biotechnologies (Consultant, Advisor or Review Panel member)Blavatnik (Grant/Research Support)HHMI (Grant/Research Support)Mathers (Grant/Research Support)NIH (Grant/Research Support)Spring Discovery (Grant/Research Support)Spring Discovery (Consultant, Advisor or Review Panel member)Vedanta InProTher (Consultant, Advisor or Review Panel member)Yale School of Medicine (Grant/Research Support) Nathan D. Grubaugh, PhD, Tempus Labs (Consultant) Ronika Alexander-Parrish, RN, MAEd, Pfizer (Employee, Shareholder) Adriano Arguedas, MD, Pfizer (Employee) Bradford D. Gessner, MD, MPH, Pfizer Inc. (Employee) Daniel Weinberger, PhD, Affinivax (Consultant)Merck (Consultant, Grant/Research Support)Pfizer (Consultant, Grant/Research Support) Anne Wyllie, PhD, Global Diagnostic Systems (Consultant)Pfizer (Advisor or Review Panel member, Research Grant or Support)PPS Health (Consultant)Tempus Labs, Inc (Research Grant or Support)

One-Year Quality of Life Post-Pneumonia Diagnosis in Japanese Adults

BACKGROUND

Pneumonia is a common, serious illness in the elderly, with a poorly characterized long-term impact on health-related quality of life (HRQoL). The Japanese Goto Epidemiology Study is a prospective, active, population-based surveillance study of adults with X-ray/CT scan-confirmed community-onset pneumonia, assessing the HRQoL outcome quality-adjusted life-years (QALYs). We report QALY scores and losses among a subset of participants in this study.

METHODS

QALYs were derived from responses to the Japanese version of the EuroQol-5D-5L health-state classification instrument at days 0, 7, 15, 30, 90, 180, and 365 after pneumonia diagnosis from participants enrolled from June 2017 to May 2018. We used patients as their own controls, calculating comparison QALYs by extrapolating EuroQol-5D-5L scores for day -30, accounting for mortality and changes in scores with age.

RESULTS

Of 405 participants, 85% were aged ≥65 years, 58% were male, and 69% were hospitalized for clinically and radiologically confirmed pneumonia. Compliance with interviews by patients or proxies was 100%. Adjusted EuroQol-5D-5L scores were 0.759, 0.561, 0.702, and 0.689 at days -30, 0 (diagnosis), 180, and 365, respectively. Average scores at all time points remained below the average day -30 scores (P ≤ .001). Pneumonia resulted in a 1-year adjusted loss of 0.13 QALYs (~47.5 quality-adjusted days) (P < .001).

CONCLUSIONS

Substantial QALY losses were observed among Japanese adults following pneumonia diagnosis, and scores had not returned to prediagnosis levels at 1 year postdiagnosis. QALY scores and cumulative losses were comparable to those in US adults with chronic heart failure, stroke, or renal failure.

Upper respiratory tract colonization with Streptococcus pneumoniae in adults

INTRODUCTION

Most of the current evidence regarding pneumococcal upper respiratory colonization in adults suggests that despite high disease burden, carriage prevalence is low. Contemporary studies on adult pneumococcal colonization have largely followed the pediatric approach by which samples are obtained mostly from the nasopharynx and bacterial detection is evaluated by routine culture alone. Recent evidence suggests that the 'pediatric approach' may be insufficient in adults and pneumococcal detection in this population may be improved by longitudinal studies that include samples from additional respiratory sites combined with more extensive laboratory testing.

AREAS COVERED

In this article, relevant literature published in peer review journals on adult pneumococcal colonization, epidemiology, detection methods, and recommendations were reviewed.

EXPERT OPINION

Respiratory carriage of Streptococcus pneumoniae has been underestimated in adults. Contemporary pneumococcal carriage studies in adults that collect samples from alternative respiratory sites such as the oropharynx, saliva, or nasal wash; are culture-enriched for pneumococcus; and use molecular diagnostic methods designed to target two pneumococcal DNA sequences should enhance pneumococcal detection in the adult respiratory tract. This finding may have implications for the interpretation of dynamics of pneumococcal transmission and vaccination.

Tick-borne encephalitis in China: A review of epidemiology and vaccines

Tick-borne encephalitis (TBE) has been shown to be endemic in northern and western China, including the three mountain areas in Heilongjiang, Jilin, Inner Mongolia, and Xinjiang. In addition, serology evidence shows that there is human infection in south-west provinces of China, including Xizang (Tibet) and Yunnan. TBE in China is caused by the Far Eastern TBE virus subtype and there is no biphasic course for disease presentation. The majority of TBE cases in China have occurred in people who were living or working in forests. TBE vaccines became available in China soon after the virus was identified in the country and they have been used for more than 60years to date, with different vaccine types used in different periods. Currently, an inactivated and purified whole-virus vaccine produced in a primary hamster kidney (PHK) cell line is used. Clinical trials have shown this vaccine to have higher immunogenicity and fewer adverse reactions than previous TBE vaccines. This paper provides a review on the epidemiology of TBE and the history of TBE vaccination in China.

In vitro Activity of Cefditoren against Middle Ear Fluid Isolates from Costa Rican Children with Otitis Media

Otitis media (OM) is one of the most common infections in children, Streptococcus pneumoniae and nontypable Haemophilus influenzae being the two most common pathogens isolated in the middle ear fluid (MEF) of children with OM. Cefditoren is a third-generation cephalosporin with broad-spectrum antibacterial activity, including activity against those pathogens commonly causing OM, with enhanced stability against common β-lactamases. The main objective of this study was to evaluate the in vitro activity of cefditoren against pathogens collected from the MEF of Costa Rican children with OM between 2006 and 2011. A total of 715 samples were analyzed. Among the 89 S. pneumoniae strains that were penicillin-nonsusceptible, only 7% were cefditoren-resistant according to Spanish Regulatory Agency criteria; among the H. influenza and M. catarrhalis isolates obtained, 100 and 90% of the isolates, respectively, were cefditoren-susceptible. MIC50/90 against the 207 PCV-13 S. pneumoniae serotyped strains and the 79 serotypes not covered by PCV-13 for cefditoren were 0.03/1 and 0.03/0.12 mg/l, respectively. For both amoxicillin-susceptible and resistant H. influenzae strains, the MIC range against cefditoren was from ≤0.015 to 0.06 mg/l as well. In conclusion, the confirmation of the wide spectrum of activity of cefditoren and its intrinsic strength against resistant strains allows us to suggest that cefditoren might be included as one of the best choices among antibiotics that are widely used in empiric therapy for OM in pediatric patients.

Etiology and antimicrobial susceptibility of middle ear fluid pathogens in Costa Rican children with otitis media before and after the introduction of the 7-valent pneumococcal conjugate vaccine in the National Immunization Program: acute otitis media microbiology in Costa Rican children

Acute otitis media (AOM) microbiology was evaluated in children after 7-valent pneumococcal conjugate vaccine (PCV7) introduction in Costa Rica (private sector, 2004; National Immunization Program, 2009). This was a combined prospective and retrospective study conducted in a routine clinical setting in San José, Costa Rica. In the prospective part of the study, which was conducted post-PCV7 introduction (2010-2012), standard bacteriological procedures were used to evaluate the etiology and serotype distribution of middle ear fluid samples collected by tympanocentesis or otorrhea from children aged 3-59 months diagnosed with AOM. E-tests were used to evaluate antimicrobial susceptibility in culture-positive samples. Retrospective data recorded between 1999 and 2004 were used for comparison of bacterial etiology and serotype distribution before and after PCV7 introduction. Statistical significance was evaluated in bivariate analyses at the P-value < 0.05 level (without multiplicity correction). Post-PCV7 introduction, Haemophilus influenzae was detected in 118/456 and Streptococcus pneumoniae in 87/456 AOM episodes. Most H. influenzae isolates (113/118) were non-typeable. H. influenzae was more (27.4% vs 20.8%) and S. pneumoniae less (17.1% vs 25.5%) frequently observed in vaccinated (≥ 2 PCV7 doses or ≥ 1 PCV7 dose at >1 year of age) versus unvaccinated children. S. pneumoniae non-susceptibility rates were 1.1%, 34.5%, 31.7%, and 50.6% for penicillin, erythromycin, azithromycin, and trimethoprim/sulfamethoxazole (TMP-SMX), respectively. H. influenzae non-susceptibility rate was 66.9% for TMP-SMX. Between pre- and post-PCV7 introduction, H. influenzae became more (20.5% vs 25.9%; P-value < 0.001) and S. pneumoniae less (27.7% vs 19.1%; P-value = 0.002) prevalent, and PCV7 serotype proportions decreased among pneumococcal isolates (65.8% vs 43.7%; P-value = 0.0005). Frequently identified pneumococcal serotypes were 19F (34.2%), 3 (9.7%), 6B (9.7%), and 14 (9.7%) pre-PCV7 introduction, and 19F (27.6%), 14 (8.0%), and 35B (8.0%) post-PCV7 introduction. Following PCV7 introduction, a change in the distribution of AOM episodes caused by H. influenzae and pneumococcal serotypes included in PCV7 was observed in Costa Rican children. Pneumococcal vaccines impact should be further evaluated following broader vaccination coverage.

A pilot study of single-dose azithromycin versus three-day azithromycin or single-dose ceftriaxone for uncomplicated acute otitis media in children

BACKGROUND

The pharmacokinetic profile of azithromycin supports its use as single-dose therapy for uncomplicated acute otitis media (AOM) in children.

OBJECTIVE

This study was designed to (1) compare the safety of single-dose oral azithromycin, 3 daily doses of oral azithromycin, and a single dose of intramuscular ceftriaxone for the treatment of uncomplicated AOM in children, and (2) provide preliminary efficacy data to support initiation of a larger, comparative trial of single-dose azithromycin for the treatment of uncomplicated acute otitis media in children.

METHODS

In this single-center pilot study, children with uncomplicated AOM were randomly assigned to receive single-dose oral azithromycin (30 mg/kg), 3-day oral azithromycin (10 mg/kg once daily), or single-dose intramuscular ceftriaxone (50 mg/kg). Tympanocentesis was performed before administration of the first dose, and clinical response was assessed on days 14-15 and 28-30.

RESULTS

Between September 1995 and May 1997, 198 children (mean age, 2.5 years) were enrolled. All of the patients were evaluable for the safety and clinical intent-to-treat (ITT) analyses, and 98 were evaluable for the microbiologic ITT analysis. On day 14-15, rates of clinical success (cure or improvement) for the 3 treatment groups were: 62/64 (97%) for single-dose azithromycin, 60/63 (95%) for 3-day azithromycin, and 61/62 (98%) for single-dose ceftriaxone. On day 28-30, the corresponding clinical success rates were 61/65 (94%), 61/66 (92%), and 62/64 (97%). For the 98 microbiologically evaluable patients, clinical success rates at day 14-15 were 28/30 (93%) for single-dose azithromycin, 31/35 (89%) for 3-day azithromycin, and 33/33 (100%) for single-dose ceftriaxone. On day 28-30, the corresponding clinical success rates were 27/30 (90%), 30/35 (86%), and 32/33 (97%). Treatment-related adverse event rates for single-dose azithromycin, 3-day azithromycin, and single-dose ceftriaxone were 10.6%, 9.1%, and 9.1%, respectively.

CONCLUSION

In this pilot study comparing single-dose azithromycin, 3-day azithromycin, and single-dose ceftriaxone for the treatment of uncomplicated AOM in children, no differences were detected among the 3 regimens.

Global and regional burden of hospital admissions for severe acute lower respiratory infections in young children in 2010: a systematic analysis

BACKGROUND

The annual number of hospital admissions and in-hospital deaths due to severe acute lower respiratory infections (ALRI) in young children worldwide is unknown. We aimed to estimate the incidence of admissions and deaths for such infections in children younger than 5 years in 2010.

METHODS

We estimated the incidence of admissions for severe and very severe ALRI in children younger than 5 years, stratified by age and region, with data from a systematic review of studies published between Jan 1, 1990, and March 31, 2012, and from 28 unpublished population-based studies. We applied these incidence estimates to population estimates for 2010, to calculate the global and regional burden in children admitted with severe ALRI in that year. We estimated in-hospital mortality due to severe and very severe ALRI by combining incidence estimates with case fatality ratios from hospital-based studies.

FINDINGS

We identified 89 eligible studies and estimated that in 2010, 11·9 million (95% CI 10·3-13·9 million) episodes of severe and 3·0 million (2·1-4·2 million) episodes of very severe ALRI resulted in hospital admissions in young children worldwide. Incidence was higher in boys than in girls, the sex disparity being greatest in South Asian studies. On the basis of data from 37 hospital studies reporting case fatality ratios for severe ALRI, we estimated that roughly 265,000 (95% CI 160,000-450,000) in-hospital deaths took place in young children, with 99% of these deaths in developing countries. Therefore, the data suggest that although 62% of children with severe ALRI are treated in hospitals, 81% of deaths happen outside hospitals.

INTERPRETATION

Severe ALRI is a substantial burden on health services worldwide and a major cause of hospital referral and admission in young children. Improved hospital access and reduced inequities, such as those related to sex and rural status, could substantially decrease mortality related to such infection. Community-based management of severe disease could be an important complementary strategy to reduce pneumonia mortality and health inequities.

FUNDING

WHO.

Streptococcus pneumoniae serotypes isolated from the middle ear fluid of Costa Rican children following introduction of the heptavalent pneumococcal conjugate vaccine into a limited population

BACKGROUND

The heptavalent pneumococcal conjugate vaccine (PCV-7) was introduced in high risk children and into the private market in Costa Rica in 2004 (<5% annual birth cohort). The aim of this study was to compare the Streptococcus pneumoniae serotype (ST) distribution, antibiotic resistance patterns and potential coverage before and after partial introduction of PCV-7.

METHODS

A comparison between the S. pneumoniae isolates obtained and serotyped from the middle ear fluid (MEF) of Costa Rican children with otitis media between years 1999 and 2003 (before PCV-7 usage) and those isolates obtained from 2004 to 2008.

RESULTS

A total of 145 and 218 MEF S. pneumoniae were serotyped between years 1999 and 2003 and 2004 and 2008, respectively. Considering a 19F outbreak observed between years 1999 and 2003, the following statistically significant changes in serotype distribution were detected between 1999 and 2003 and 2004 and 2008: ST 3: 4.8-12.8% (P=0.01); ST 11A: 0-4.1% (P=0.01); ST 14: 3.5-21.1% (P<0.001) and ST 19F: 52.4-18.3% (P<0.05). Comparison of the two study periods demonstrated that during 2004 and 2008 a statistically significant decrease in penicillin non-susceptible serotypes (36.2-20.4% [P=0.003]) and a statistically significant increase in trimethoprim-sulfametoxazole resistant serotypes (54.9-68.5%, respectively [P=0.03]) was observed. Potential pneumococcal vaccines coverage between 1999 and 2003 and between 2004 and 2008 were: for PCV-7: 77.2-60.5%, respectively (P=0.001); for the 10-valent conjugated vaccine (PCV-10): 78.6-61.4%, respectively (P=0.0008) and for the 13-valent conjugated vaccine (PCV-13): 84.8-79.3%, respectively (P=0.2).

CONCLUSIONS

Changes in the serotype distribution and antimicrobial susceptibility of MEF S. pneumoniae have been observed in Costa Rican children with OM. Because of the limited use of PCV-7 during the study period, these changes probably cannot be attributed to PCV-7 use. Between 2004 and 2008, PCV-13 offered the highest potential vaccine coverage.

Acute otitis media severity of symptom score in a tympanocentesis study

We followed symptoms of children with acute otitis media (AOM), who were enrolled in a clinical trial that included a baseline tympanocentesis. We observed marked and rapid improvement in symptom scores after tympanocentesis. Although symptom scores (measured by the AOM-SOS) correlated with overall clinical assessment and bacteriologic outcome, the early effect of tympanocentesis rendered the AOM-SOS less useful as a primary outcome measure.

Otitis media across nine countries: disease burden and management

OBJECTIVE

To assess the perceived disease burden and management of otitis media (OM) among an international cohort of experienced physicians.

METHODS

A cross-sectional survey conducted in France, Germany, Spain, Poland, Argentina, Mexico, South Korea, Thailand and Saudi Arabia. Face-to-face interviews conducted with 1800 physicians (95% paediatricians, 5% family practitioners).Main outcome measures were the perceived burden on clinical practice (number of cases, complications and referrals) and first- and second-line management strategies for OM. Results are expressed as mean and range across the nine countries over three continents.

RESULTS

Respondents estimated an average annual caseload of 375 (range 128-1003) children under 5 years of age with OM; 54% (range 44-71%) with an initial episode and 38% (range 27-54%) with recurrent OM (ROM). OM with complications was estimated to be approximately 20 (range 7-49) cases per year and an estimated 15% (8-41%) of children with OM was recalled as needing specialist referral. There was high awareness of Streptococcus pneumoniae and Haemophilus influenzae as causative bacterial pathogens: 77% (range 65-91%) and 74% (range 68-83%), respectively, but less recognition of non-typeable H. influenzae (NTHi); 59% (range 45-67%). Although concern over antimicrobial resistance was widespread, empirical treatment with antibiotics was the most common first-line treatment (mean 81%, range 40-96%). The burden of disease is substantial enough that many physicians would consider vaccination to prevent OM (mean score 5.1, range 4.3-6.2 on 1-7 scale).

CONCLUSIONS

This large, multinational survey shows that OM remains a significant burden for clinical practice. Despite awareness of shortcomings, antimicrobial therapy remains the most frequent treatment for OM.

Safety and immunogenicity of one dose of MenACWY-CRM, an investigational quadrivalent meningococcal glycoconjugate vaccine, when administered to adolescents concomitantly or sequentially with Tdap and HPV vaccines

This Phase III study evaluates an investigational quadrivalent meningococcal CRM(197) conjugate vaccine, MenACWY-CRM (Novartis Vaccines), when administered concomitantly or sequentially with two other recommended adolescent vaccines; combined tetanus, reduced diphtheria and acellular pertussis (Tdap), and human papillomavirus (HPV) vaccine. In this single-centre study, 1620 subjects 11-18 years of age, were randomized to three groups (1:1:1) to receive MenACWY-CRM concomitantly or sequentially with Tdap and HPV. Meningococcal serogroup-specific serum bactericidal assay using human complement (hSBA), and antibodies to Tdap antigens and HPV virus-like particles were determined before and 1 month after study vaccinations. Proportions of subjects with hSBA titres > or =1:8 for all four meningococcal serogroups (A, C, W-135, Y) were non-inferior for both concomitant and sequential administration. Immune responses to Tdap and HPV antigens were comparable when these vaccines were given alone or concomitantly with MenACWY-CRM. All vaccines were well tolerated; concomitant or sequential administration did not increase reactogenicity. MenACWY-CRM was well tolerated and immunogenic in subjects 11-18 years of age, with comparable immune responses to the four serogroups when given alone or concomitantly with Tdap or HPV antigens. This is the first demonstration that these currently recommended adolescent vaccines could be administered concomitantly without causing increased reactogenicity.

Microbiology of the middle ear fluid in Costa Rican children between 2002 and 2007

BACKGROUND

Because the microbiology and susceptibility patterns of middle ear fluid pathogens in children with otitis media change over time, an active surveillance is recommended to establish appropriate therapeutic guidelines.

OBJECTIVE

To analyze the microbiology and susceptibility pattern of middle ear pathogens obtained from Costa Rican children with acute otitis media (AOM), recurrent otitis media (ROM) and therapeutic failure otitis media (OMTF) between 2002 and 2007.

PATIENTS AND METHODS

1108 children aged 2-92 months who participated in various otitis media clinical trials between the years 2002 and 2007.

RESULTS

Among the study population, 880 were children with AOM (61% <24 months of age), 138 were children with ROM (54% <24 months of age) and 90 were children with OMTF (67% <24 months of age). Bilateral otitis media was more frequent in children with OMTF (44%) than in children with AOM (37%) (P=0.19) and ROM (27%) (P=0.009). Presence of siblings <8 years of age was more frequently observed in children with OMTF (73%) than in children with ROM (65%) (P=0.0001) and AOM (47%) (P=0.000002). Overall Streptococcus pneumoniae (44%) was the most common pathogen isolated followed by Haemophilus influenzae (37%), Moraxella catarrhalis (11%) and Streptococcus pyogenes (4%). S. pneumoniae was the most common pathogen in AOM (44%) and ROM (47%), however, H. influenzae was the most common pathogen in OMTF (40%). Among all H. influenzae, an increase in the number of β-lactamase producing strains was observed from 5.2% in 2001 to 14% (P=0.04) in 2007 and this was associated with an increase in the use of amoxicillin. An increase in the number of M. catarrhalis was also observed, from 3% (9/350) in 2001 to 11% (71/628) (P=0.000003) in 2007. During the study period the incidence of penicillin non-susceptible S. pneumoniae was 42/211 (20%) in children with AOM; 5/35 (17%) in children with ROM and 5/17 (42%) in children with OMTF. M. catarrhalis cases increased from 8% in 2004 to 17% in 2007 (P=0.0005) and S. pyogenes decreased from 7% in 2002-2004 to 1% in 2005-2007 (P=0.001).

CONCLUSIONS

In Costa Rica, S. pneumoniae remains the most common pathogen in children with AOM and ROM whereas non-typable H. influenzae remains the most common pathogen in children with OMTF. A significant increase in the number of β-lactamase positive H. influenzae and M. catarrhalis has been observed in recent years.

Streptococcus pneumoniae serotype 3 among Costa Rican children with otitis media: clinical, epidemiological characteristics and antimicrobial resistance patterns

BACKGROUND

After the introduction of the seven valent-pneumococcal conjugated vaccine into our National Immunization Program, it is important to establish and track local serotype distribution in order to evaluate its impact specially because serotype replacement phenomena has been described.To describe the clinical, epidemiological and antimicrobial resistance patterns of Costa Rican children with otitis media caused by Streptococcus pneumoniae serotype 3.

METHODS

Middle ear fluid samples were obtained from Costa Rican children with otitis media who participated in various antimicrobial clinical trials between 1992 and 2007. Streptococcus pneumoniae was identified according to laboratory standard procedures. Strains were serotyped and antimicrobial susceptibility to penicillin, amoxicillin, cefuroxime, ceftriaxone, azithromycin and levofloxacin was determined by E-test.

RESULTS

Throughout 1992-2007 a total of 1919 tympanocentesis were performed in children with otitis media (median age: 19 months) and yielded a total of 1208 middle ear isolates. The most common pathogens were: Streptococcus pneumoniae, 511 isolates (49%); Non-Typable Haemophilus influenzae, 386 isolates (37%); Moraxella catarrahalis, 100 isolates (9.5%); and Streptococcus pyogenes, 54 isolates (5%). Streptococcus pneumoniae serotyping was performed in 346/511 isolates (68%) recovered during years 1999-2006. The most common serotypes were 19F (101/30.0%), 14 (46/13.7%), 3 (34/10.1%), 6B (30/8.9%) and 23F (23/6.8%). Analysis performed per years showed a higher prevalence of serotype 3 Streptococcus pneumoniae during the study period 2004 and 2005. During the entire study period (1999-2006) serotype 3 was most commonly isolated in children older than 24 months (61.2% vs 40.6%;P = 0.05) and showed a lower rate of penicillin non-susceptibility (4.0% vs 18%; P = 0.003).

CONCLUSION

Streptococcus pneumoniae serotype 3 is an important pathogen in Costa Rican children with otitis media, especially in children older than 24 months of age (P = 0.05). Most serotype 3 isolates were susceptible to penicillin, cephalosporins, macrolides and quinolones.

Understanding the link between pneumococcal serotypes and invasive disease

To determine the relationship between serotypes and the burden of pneumococcal disease in Latin American children, population- and laboratory-based surveillance data for the region were evaluated. Streptococcus pneumoniae continues to be an important bacterial pathogen causing infections in children. A seven-valent pneumococcal conjugate vaccine (PCV7) has been documented to be extremely effective in the prevention of invasive and non-invasive S. pneumoniae infections due to vaccine serotypes. However, due to evolving epidemiology, there is a need to enhance S. pneumoniae serotype coverage in future generation vaccines, complemented by ongoing surveillance of pneumococcal serotypes following vaccine introduction.

Comparative study of levofloxacin in the treatment of children with community-acquired pneumonia

BACKGROUND

Levofloxacin has established efficacy and safety in the treatment of community-acquired pneumonia (CAP) in adults, and its use as an alternative therapy for children with CAP has been proposed.

OBJECTIVE

Assess the clinical efficacy and safety of levofloxacin compared with standard of care antibiotic therapy in the treatment of CAP in children aged 6 months to 16 years.

METHODS

In an open-label, multicenter, noninferiority trial, children with CAP were randomized 3:1 to receive levofloxacin or comparator antimicrobial therapy (0.5 to <5 years: amoxicillin/clavulanate or ceftriaxone; > or =5 years: clarithromycin or ceftriaxone with clarithromycin or erythromycin lactobinate) for 10 days. The primary outcome was cure rates at the test-of-cure visit (10-17 days after completing treatment) as determined by symptoms, physical examination, and chest radiography.

RESULTS

Seven hundred and thirty-eight children were enrolled and 539 (405 levofloxacin-treated, 134 comparator-treated) were clinically evaluable at test-of-cure visit. Clinical cure rates were 94.3% (382 of 405) in levofloxacin-treated and 94.0% (126 of 134) in comparator-treated children. Cure rates were also similar for levofloxacin and comparator for each age group (<5 years, 92.2% versus 90.8%; > or =5 years, 96.5% versus 97.1%; respectively) and for children categorized as being at higher risk for severe disease. Mycoplasma pneumoniae was the most frequently identified cause of pneumonia (230 children). Levofloxacin was as well tolerated as comparators, with similar type and incidence of adverse events.

CONCLUSIONS

Levofloxacin was as well tolerated and effective as standard-of-care antibiotics for the treatment of CAP in infants and children.

Comparative safety profile of levofloxacin in 2523 children with a focus on four specific musculoskeletal disorders

BACKGROUND

Fluoroquinolones, including levofloxacin, have not been recommended for use in children largely because studies in juvenile laboratory animals suggest there may be an increased risk of fluoroquinolone-associated cartilage lesions. A large prospective trial is needed to assess the risks associated with using levofloxacin in children.

OBJECTIVE

Assess the safety and tolerability of levofloxacin therapy in children based on observations for 1 year after therapy.

METHODS

Safety data were collected in children who participated in 1 of 3 efficacy trials (N = 2523) and a subset of these children who also subsequently participated in a long-term 1-year surveillance trial (N = 2233). Incidence of adverse events in children randomized to receive levofloxacin versus nonfluoroquinolone antibiotics was compared. Based on assessments by treating physicians and an independent data safety monitoring committee, events related to the musculoskeletal system were further categorized as 1 of 4 predefined musculoskeletal disorders (arthralgia, arthritis, tendinopathy, gait abnormality) considered most likely clinical correlates of fluoroquinolone-associated cartilage lesions observed in laboratory animals.

RESULTS

Levofloxacin was well tolerated during and for 1 month after therapy as evidenced by similar incidence and character of adverse events compared with nonfluoroquinolone antibiotics. However, incidence of at least 1 of the 4 predefined musculoskeletal disorders (largely due to reports of arthralgia) was greater in levofloxacin-treated compared with nonfluoroquinolone-treated children at 2 months (2.1% vs. 0.9%; P = 0.04) and 12 months (3.4% vs. 1.8%; P = 0.03) after starting therapy.

CONCLUSIONS

The incidence of 1 or more of the 4 predefined musculoskeletal disorders identified in nonblinded, prospective evaluations, was statistically greater in levofloxacin-treated compared with comparator-treated children.

Pharmacokinetics and pharmacodynamics of gatifloxacin in children with recurrent otitis media: application of sparse sampling in clinical development

Gatifloxacin is a 4th-generation fluoroquinolone previously under investigation for the treatment of otitis media in infants and children. These analyses were designed to evaluate the extent of drug exposure relative to adult populations and to examine the relationship between drug exposure and response to therapy in children with recurrent otitis media or early treatment failures of acute otitis media. The patient population included 187 patients from an open-label, multicenter, noncomparative study using gatifloxacin 10 mg/kg once daily. Gatifloxacin exposure was estimated using a single steady-state blood sample in conjunction with a pharmacostatistical model developed using a separate pediatric data set. Gatifloxacin exposure was equivalent to that in adults given 400 mg daily. Of the 41 patients who had Streptococcus pneumoniae from middle ear culture, there were only 3 bacteriologic failures; there was no relationship between plasma fu AUC(0-24):MIC ratio and outcome. In conclusion, population pharmacokinetic/pharmacodynamic methods allowed estimation of drug exposure using one sample per patient.

Activity of faropenem against middle ear fluid pathogens from children with acute otitis media in Costa Rica and Israel

Faropenem was tested against 1,188 middle ear fluid pathogens from children in Israel and Costa Rica. Against Streptococcus pneumoniae and Haemophilus influenzae, faropenem was the most active beta-lactam, with activity that was similar to or greater than of the other oral antimicrobial classes studied. Faropenem was also active against Moraxella catarrhalis and Streptococcus pyogenes.

An open-label, double tympanocentesis, single-center study of trimethoprim sulfametoxasole in children with acute otitis media

Trimethoprim sulfamethoxasole has been recommended for the treatment of acute otitis media. In this double tympanocentesis study, children aged 3 to 48 months with acute otitis media received trimethoprim sulfamethoxasole twice daily (40 mg/kg/d) for 10 days. All children had a baseline tympanocentesis and in culture-positive children, tympanocentesis was repeated at the on-therapy visit. Of 89 children enrolled, 51 (57%) were clinically and bacteriologically evaluable. Bacteriologic eradication was achieved in 80% (42 of 52) of children, and overall clinical response at the end of therapy was 78%. Clinical success was 69% for culture-positive children versus 91% for culture-negative children at baseline tympanocentesis (P = 0.03). In this study, trimethoprim sulfamethoxasole clinical response was unsatisfactory, especially among culture-'positive children.

Pharmacokinetics of cefprozil in plasma and middle ear fluid: in children undergoing treatment for acute otitis media

BACKGROUND

Despite the wide-scale use of cefprozil for acute otitis media (AOM), there are only limited data available regarding the pharmacokinetic profile of this agent in the pediatric population.

OBJECTIVE

To characterize the plasma and middle ear fluid (MEF) pharmacokinetic profile of cefprozil in pediatric patients with AOM.

METHODS

Pharmacokinetic sampling was obtained as part of a phase IV, multicenter, open-label study of children with AOM receiving cefprozil suspension 15 mg/kg twice daily. A single blood sample was obtained 4-6 days after the initiation of cefprozil therapy and a simultaneous MEF sample was obtained by tympanocentesis when clinically indicated. Cefprozil concentrations in both matrices were determined using a validated high-performance liquid chromatography methodology. A composite profile of cefprozil concentration data in each matrix was constructed and values for the pharmacokinetic parameters were obtained using conventional modeling techniques.

RESULTS

Plasma concentrations were obtained in 53 children aged 6-48 months. In this population the maximum concentration (C(max)) in plasma was 9.18 microg/mL, the time to C(max) (t(max)) was 1.5 hours, and the terminal elimination half-life (t((1/2))(beta)) was 0.98 hours. Simultaneous plasma and MEF concentration data were available in 22 children. In this subset the C(max) in plasma was 8.2 microg/mL, the t(max) was 1.9 hours, and the t((1/2))(beta) was 1.02 hours; the corresponding MEF C(max) was 2.4 microg/mL, the t(max) was 3.5 hours, and the t((1/2))(beta) was 1.23 hours. Cefprozil MEF penetration as assessed using the ratio of the area under the concentration-time curves from the two matrices was 28%. Moreover, concentrations in MEF approximated 1 microg/mL 6 hours' post-dose.

CONCLUSIONS

The plasma profile of cefprozil in the current analysis is consistent with previously reported values in children receiving the 15 mg/kg twice daily dose. MEF penetration and the duration of drug exposure at the site of infection support the clinical utility of this agent for organisms with minimum inhibitory concentrations (MIC) of < or =1 microg/mL. However, these results also predict higher clinical failure when using this dose of cefprozil against penicillin-non-susceptible Streptococcus pneumoniae or Haemophilus influenzae because of typically higher MIC values for these organisms.

An open-label, double tympanocentesis study of levofloxacin therapy in children with, or at high risk for, recurrent or persistent acute otitis media

BACKGROUND

Levofloxacin has excellent activity against common respiratory pathogens and therefore is likely to be effective in treating children with persistent or recurrent otitis media.

OBJECTIVE

The objective of this study was to assess the efficacy and safety of levofloxacin treatment in the eradication of bacterial pathogens from the middle ear fluid (MEF) of children with, or at high risk for, persistent or recurrent otitis media.

METHODS

An open-label multicenter trial was conducted that involved tympanocentesis at entry and selectively 3 to 5 days after starting levofloxacin (10 mg/kg twice a day for 10 days).

RESULTS

: Two hundred five children (80% < or =2 years) were enrolled. One child did not have a confirmed diagnosis of acute otitis media and did not return for follow-up visits. Of the remaining 204 children, 94 (46%) had bilateral infection and 63 (31%) were receiving antimicrobials immediately before entry. One hundred five isolates of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus. pyogenes were recovered in pure or mixed cultures. All isolates were susceptible to levofloxacin. During-treatment bacterial eradication from MEF occurred in 88% (78 of 89) of bacteriologically evaluable patients, including 90% (65 of 72) of children < or =24 months of age. Bacteria initially isolated from MEF were eradicated in 31 of 37 (84%) children infected with S. pneumoniae and in 54 of 54 (100%) children infected with H. influenzae. Overall, clinical success rate after therapy was 94% for the total study population and 92% for the bacteriologically evaluable population. Levofloxacin was well tolerated. Vomiting (4%) was the most common treatment-limiting adverse event.

CONCLUSIONS

Levofloxacin was safe and effective in treating and eradicating common bacterial pathogens from MEF in children with, or at risk for, recurrent or persistent otitis media.

Single-dose azithromycin for the treatment of children with acute otitis media

Azithromycin is an azalide with in vitro activity against otitis media pathogens, good middle ear penetration and a prolonged half-life. A total of four clinical trials have evaluated the clinical success rate, safety and compliance of single-dose azithromycin (30 mg/kg) in the treatment of children with otitis media. Among all the patients treated with single-dose azithromycin (30 mg/kg), and presented previously in four published clinical trials, end-of-treatment clinical success was 88% (544 out of 619) and maintained clinical success at the end-of-study was 82% (498 out of 610). Three of the four studies included a mandatory baseline tympanocentesis. The overall end-of-treatment and end-of-study clinical success rates among all culture-positive patients was 84% (222 out of 263) and 80% (210 out of 263), respectively. Per pathogen end-of-treatment clinical success rates observed were 91% (125 out of 137) among patients with Streptococcus pneumoniae, 77% (75 out of 97) among patients with Haemophilus influenzae, 100% (14 out of 14) among patients with Moraxella catarrhalis, 64% (seven out of 11) among patients with baseline Streptococcus pyogenes and 25% (one out of four) among patients with a S. pneumoniae and H. influenzae mixed infection. Clinical success was observed in 90% (106 out of 118) of patients with baseline macrolide-susceptible S. pneumoniae and in 67% (14 out of 21) among patients with baseline macrolide-resistant S. pneumoniae (p = 0.01). Adverse events were uncommon, mostly mild and transitory gastrointestinal complaints, and in the two larger comparative trials, were less frequent than the rates observed with the comparator agents. Compliance was excellent (99-100%). Single-dose azithromycin (30 mg/kg) represents an alternative for the treatment of pediatric patients with uncomplicated acute otitis media, particularly in those geographic regions where high-level S. pneumoniae macrolide resistance is uncommon, and for those patients that require directly observed therapy or when compliance may be a problem.