Impacto de la vacuna neumocócica conjugada heptavalente en una población con valores bajos-intermedios de vacunación

[Incidence and lethality of invasive pneumococcal disease in Tarragona, Spain, 2006-2009]

An epidemiological study was conducted on all cases of invasive pneumococcal disease (IPD) diagnosed in Tarragona, Spain, between 1 January 2006 and 31 December 2009. A total of 286 IPD cases were observed, which was an overall incidence of 21.2 episodes per 100,000 persons-year (95% CI: 16.6-26.9). Incidence rates were 26.3/100,000 (95% CI: 14.4-44.3) among children, 12.2/100,000 (95% CI: 8.2-17.6) among patients between 15-64 years and 59.6/100,000 (95% CI: 40.0-85.8) in those ≥65 years. Overall lethality rate was 7.3% (none in children, 3.4% among patients 15-64 years, and 14.8% among patients ≥65 years; p<0.001).

A review of the impact of pneumococcal polysaccharide conjugate vaccine (7-valent) on pneumococcal meningitis

INTRODUCTION

Streptococcus pneumoniae is the leading cause of bacterial meningitis. Young children, the elderly and those who are immunocompromised or who suffer from chronic diseases have the highest risk of developing pneumococcal meningitis. A 7-valent pneumococcal conjugate vaccine (PCV7) was licensed in 2000 in the US and in 2001 in Europe.

METHODS

A literature search was performed in PubMed to identify studies assessing the impact of routine childhood PCV7 vaccination on pneumococcal diseases. Here, we report the impact on pneumococcal meningitis.

RESULTS

A total of 17 articles reporting impact data on pneumococcal meningitis were included in this review: 11 from Western Europe and 6 from North America. In the post-vaccination period, compared with the pre-vaccination period, a reduction ranging from 59.2% in the US, 1 year after vaccine introduction, to 100% in Belgium, 4 years after vaccine introduction in vaccine-type (VT) pneumococcal meningitis incidence was reported in vaccine-eligible children in seven studies. In addition, the majority of studies reported reductions in VT and all-type pneumococcal meningitis incidence in age groups that were not vaccine-eligible.

CONCLUSIONS

The results from this review demonstrate that PCV7 has had a significant impact on pneumococcal meningitis across all ages through its use in pediatric immunization programs. With the introduction of 13-valent PCV (PCV13) we can expect to see a reduction in the incidence of pneumococcal meningitis due to the six additional serotypes included, as well as continued protection against pneumococcal meningitis due to PCV7 serotypes. Robust surveillance systems are essential for the evaluation of the impact of PCV13 on all-type pneumococcal meningitis and for monitoring the evolution of non-vaccine serotype pneumococcal meningitis.

Risk factors for invasive pneumococcal disease in a community with a high proportion of non vaccine serotypes

The aim of this study was to investigate factors associated with vaccination with 7-pneumococcal conjugate vaccine (PCV7) and risk factors for invasive pneumococcal disease (IPD) and for penicillin-nonsusceptible strains in a community with intermediate vaccination coverage. We conducted a prospective, matched case-control study in children aged 3-59 months with IPD admitted to two hospitals in Catalonia. Three controls matched by hospital, age, sex, date of hospitalization and risk medical conditions were selected for each case. We calculated odds ratios for potential risk factors using logistic regression. Of the 1075 children included, 46.6% were considered fully vaccinated by age. 91.1% of cases were caused by non-PCV7 serotypes. Vaccination with PCV7 was positively associated with attending day care or school and negatively associated with age 24-59 months, >4 cohabitants and low social class. Attending day care or school and >4 cohabitants were risk factors for IPD. Previous antibiotic treatment in children aged 24-59 months was a protective factor for IPD; however, antibiotic use in the previous month and age <24 months were associated with penicillin-nonsusceptible IPD. In a community where IPD in children aged <5 years is caused mainly by non-PCV7 Streptococcus pneumoniae serotypes and where vaccine coverage is only intermediate, attending day care or school, age <24 months, >4 cohabitants and social class were associated with vaccination. Attending day care or school was a strong risk factor for IPD, while vaccination was protective in children aged <24 months. Age and antibiotic use in the previous month were associated with penicillin-nonsusceptible IPD.

Pharmacoeconomic assessment of implementing a universal PCV-13 vaccination programme in the Valencian public health system (Spain)

BACKGROUND

Heptavalent pneumococcal conjugate vaccine (PCV-7) was licensed to provide immunity against pneumococcal disease caused by seven serotypes of S. pneumoniae. Thirteen-valent pneumococcal conjugate vaccine (PCV-13) includes 6 additional serotypes for preventing invasive pneumococcal disease.

OBJECTIVE

The objective of this study was to estimate the potential health benefits, costs, and cost-effectiveness of vaccination with PCV-13 in the Community of Valencia and to generate valuable information for policy makers at regional and country levels.

METHODS

A decision tree was designed to determine the health and economic outcomes in hypothetical cohorts of vaccinated and unvaccinated children followed over their lifetime. Information about disease incidence and serotype distribution were gathered from local databases and from published and unpublished local records. PCV-13 effectiveness was extrapolated from PCV-7 efficacy data. A 5% of herd effect and a serotype replacement of 25% were considered for the base case scenario. Only direct costs were taken into account and results were expressed in terms of life-years gained (LYG) and quality adjusted life years (QALY).

RESULTS

Implementing a universal PCV-13 vaccination program in the Community of Valencia would decrease the number of hospital admitted pneumonia to less than 4571 cases while avoiding 310 cases of IPD and 82,596 cases of AOM throughout the cohort lifetime. A total of 190 S. pneumoniae related deaths would be averted over the same period. Total medical costs of non-vaccinating the cohort of newborns would reach up to 403,850.859€ compared to 438,762.712€ that would represent vaccinating the cohort. The incremental cost of vaccinating the children was estimated in 12,794€/LYG and 10,407€/QALY, respectively.

CONCLUSIONS

A universal PCV-13 vaccination program in the Community of Valencia would be a cost-effective intervention from the payer perspective after preventing for pneumococcal infections and for decreasing its associated mortality and morbidity.