All-cause pneumonia in children after the introduction of pneumococcal vaccines in the United Kingdom: A population-based study

Incidence of pneumococcal disease from 2003 to 2019 in children ≤17 years in England

BACKGROUND

Pneumococcal disease is a leading cause of communicable disease morbidity and mortality globally. We aimed to estimate invasive pneumococcal disease (IPD), pneumococcal pneumonia (PP) and all-cause pneumonia (ACP) incidence rates (IRs) in children aged 0-17 years in England from 2003 to 2019.

METHODS

A retrospective study in children ≤17 years old from 2003 to 2019 using the Clinical Practice Research Datalink (CPRD) Gold and Hospital Episodes Statistics Admitted Patient Care (HES APC) databases. IPD episodes were identified in hospital records (HES APC). PP (caused by Streptococcus pneumoniae only) and ACP episodes (caused by any pathogen) were identified in primary care (CPRD) and in hospital records (HES APC). Annual IRs by age-group were calculated as the number of episodes/person-years (PY) at risk, with 95% confidence intervals (95% CI). Interrupted time series analyses were conducted to assess changes in IRs across the post-PCV7 (2007-2009), early post-PCV13 (2011-2014) and late post-PCV13 (2015-2019) periods compared to the pre-PCV7 period (2003-2005) using generalized linear models.

RESULTS

170 IPD episodes, 769 PP episodes and 12,142 ACP episodes were identified in 1,500,686 children in 2003-2019. The overall IPD, PP and ACP IRs (per 100,000 PY) were 2.29 (95% CI 1.96-2.66), 10.34 (95% CI 9.62-11.10) and 163.37 (95% CI 160.47-166.30), respectively. The highest IPD, PP and ACP IRs were observed in children aged < 2 years compared to older children (2-4 and 5-17 years). IPD IRs decreased between the pre-PCV7 period and the late post-PCV13 period from 3.28 (95% CI 2.42-4.33) to 1.41 (95% CI 0.80-2.29), IRR 0.28 (95% CI 0.09-0.90), p-value 0.033. PP IRs declined between the pre-PCV7 period and the late post-PCV13 period from 14.65 (95% CI 12.77-16.72) to 3.87 (95% CI 2.81-5.20), IRR 0.19 (95% CI 0.09-0.38), p-value < 0.001. ACP IRs declined between the pre-PCV7 period and the late post-PCV13 period from 167.28 (95% CI 160.78-173.96) to 124.96 (95% CI 118.54-131.63), IRR 0.77 (95% CI 0.66-0.88), p-value < 0.001.

CONCLUSIONS

The clinical burden of IPD, PP and ACP declined in children in England aged 0-17 years between 2003 and 2019, especially in the late post-PCV13 period. This study highlights the importance of PCV vaccination in reducing the burden of PD and ACP in children in England.

Economic burden of pneumococcal disease in children in Liguria, Italy

Vaccinations against Streptococcus pneumoniae are included in infant immunization programs globally. However, a substantial burden due to pneumococcal disease (PD) remains. This study aimed to estimate the cost of emergency department (ED) visits and hospitalizations associated with invasive pneumococcal disease, all-cause pneumonia, and acute otitis media in children <15 years of age in the Liguria region of Italy between 2012 and 2018. The retrospective cohort study used data from the Liguria Region Administrative Health Databases and the Ligurian Chronic Condition Data Warehouse, which contain information on hospital stays, outpatient visits, laboratory/imaging techniques, surgical procedures, and pharmaceutical prescriptions. Patients with one or more ED or inpatient claim for PD (based on International Classification of Diseases, Ninth Revision, Clinical Modification codes) were included. Cost of ED visits and hospitalizations were estimated from the diagnosis-related group system and procedures performed in the ED. In Ligurian children <15 years of age during 2012–2018, the median annual number of hospitalizations plus ED visits due to PD was 4,009, and the median estimated annual cost was €3.6 million. All-cause pneumonia accounted for the majority of hospitalization costs during the study period. Number and costs of ED visits and hospitalizations increased from 2012 to 2018. Despite widespread infant immunization in Liguria, economic costs due to PD-associated ED visits and hospitalizations remained high in children 0–14 years of age.

A Retrospective Analysis to Estimate the Burden of Invasive Pneumococcal Disease and Non-Invasive Pneumonia in Children <15 Years of Age in the Veneto Region, Italy

Despite advances in preventative interventions, invasive pneumococcal disease and pneumonia cause significant morbidity and mortality in children. We studied the annual incidence of pneumococcal-specific and syndromic invasive disease and non-invasive pneumonia in children <15 years of age during the early (2010−2013) and late (2014−2017) 13-valent pneumococcal conjugate vaccine (PCV13) periods in Veneto, Italy. In this retrospective observational study, pneumococcal-specific and syndromic invasive disease and non-invasive pneumonia cases were identified from several sources, including the Pedianet database. Interrupted time series analysis and Mann−Kendall tests were conducted to explore trends in incidence rates (IRs). Among 72,570 patients <15 years of age between 2010−2017, 88 episodes of pneumococcal-specific and syndromic invasive disease and 3926 episodes of non-invasive pneumonia were reported. Overall IR of pneumococcal-specific and syndromic invasive disease was 0.4/1000 person-years and did not change significantly (p = 0.46) throughout the study. Overall IR of non-invasive pneumonia was 10/1000 person-years and decreased significantly (−0.64, p = 0.026) over the study period. Following PCV13 introduction, the IRs of non-invasive pneumonia in children <15 years of age declined significantly, with no significant change in the IRs of pneumococcal-specific and syndromic invasive disease. There is a continuing clinical burden associated with pediatric pneumococcal diseases in Veneto, Italy.

A population-based analysis to determine the impact of the 13-valent pneumococcal conjugate vaccine on community-acquired pneumonia in British Columbia, Canada

BACKGROUND

Pneumonia is a leading cause of morbidity and mortality globally. We determined the impact of 13-valent pneumococcal conjugate vaccine (PCV13) use on community-acquired pneumonia (CAP) rates eight years after the vaccine was introduced in the infant immunization program.

METHODS

Using diagnostic codes from administrative databases, we calculated the overall and age-specific CAP incidence per month (2000-2018). Changes in the CAP incidence before and after the PCV13 vaccine program introduction were evaluated using negative binomial regression model adjusting for 7-valent pneumococcal conjugate vaccine program.

RESULTS

The PCV13 vaccine infant immunization program was associated with declining CAP incidence among children aged 0-2 years (adjusted Incidence Rate Ratio (aIRR): 0.91; 95% CI: 0.87-0.96). Overall CAP incidence did not decrease in those aged 3-5 years (0.98; 95% CI: 0.93-1.04), 6-17 years (1.02; 95% CI: 0.97-1.08), 18-49 years (1.02; 95% CI:0.98-1.05), 50-64 years (1.07; 95% CI: 1.04-1.11), ≥65 years (1.05; 95% CI:1.02-1.08).

CONCLUSIONS

The PCV13 infant immunization program is temporally associated with a reduction in CAP incidence in vaccine target age group. However, no significant decrease in CAP incidence in other age groups warrants further study of the etiology of CAP to develop and implement effective prevention programs.

The impact of childhood pneumococcal conjugate vaccine immunisation on all-cause pneumonia admissions in Hong Kong: A 14-year population-based interrupted time series analysis

BACKGROUND

Nine years after the introduction of pneumococcal conjugate vaccine (PCV) in the United States, Hong Kong (HK) introduced the vaccine to its universal childhood immunisation programme in 2009. We aimed to assess the impact of childhood PCV immunisation on all-cause pneumonia (ACP) admissions among the overall population of HK.

METHODS

In this population-based interrupted time series analysis, we used territory-wide population-representative electronic health records in HK to evaluate the vaccine impact. We identified hospitalised patients with a diagnosis of pneumonia from any cause between 2004 and 2017. We applied segmented Poisson regression to assess the gradual change in the monthly incidence of ACP admissions between pre- and post-vaccination periods. Negative outcome control, subgroup and sensitivity analyses were used to test the robustness of the main analysis.

FINDINGS

Over the 14-year study period, a total of 587,607 ACP episodes were identified among 357,950 patients. The monthly age-standardised incidence of ACP fluctuated between 33.42 and 87.44 per 100,000-persons. There was a marginal decreasing trend in pneumonia admissions after PCV introduction among overall population (incidence rate ratio [IRR]: 0·9965, 95% confidence interval [CI]: 0·9932-0·9998), and older adults (≥65 years, IRR: 0·9928, 95% CI: 0·9904-0·9953) but not in younger age groups.

INTERPRETATION

There was a marginally declining trend of overall ACP admissions in HK up to eight years after childhood PCV introduction. The significance disappeared when fitting sensitivity analyses. The results indicate the complexities of using non-specific endpoints for measuring vaccine effect and the necessity of enhancing serotype surveillance systems for replacement monitoring.

FUNDING

Health and Medical Research Fund, Food and Health Bureau of the Government of Hong Kong (Reference number: 18171272).

Consensus Document on Community-Acquired Pneumonia in Children. SENP-SEPAR-SEIP

Community-acquired pneumonia (CAP) is a prevalent disease among children and is frequently associated with both diagnostic and therapeutic uncertainties. Consensus has been reached between SEPAR, SENP and SEIP, and their conclusions are as follows.