7-Valent pneumococcal conjugate vaccine and lower respiratory tract infections: effectiveness of a 2-dose versus 3-dose primary series.

Background: Immunogenicity studies suggest antibody responses from a 7-valent pneumococcal conjugate vaccine (PCV7) regimen consisting of 2 doses in the primary series are less immunogenic, for at least several vaccine serotypes, compared with a regimen consisting of 3 doses; evidence of effectiveness for prevention of invasive pneumococcal disease for both regimens is available but comparative data are lacking for prevention of lower respiratory tract diseases (LRTD).

Methods: We compared rates of LRTD between children who were born in 2002 and received 2 versus 3 PCV7 doses in the primary series, both before and after receipt of the booster dose, using a retrospective matched-cohort design and health insurance claims data. Two-dose and 3-dose children were matched (1:1) using propensity scoring.

Transmission-dynamic model to capture the indirect effects of infant vaccination with Prevnar (7-valent pneumococcal conjugate vaccine (PCV7)) in older populations.

We developed an age-structured, transmission-dynamic, mathematical model to quantify the direct and indirect benefits of infant PCV7 vaccination. The model simulates the acquisition of asymptomatic carriage of Streptococcus pneumoniae and the development of fatal and non-fatal invasive pneumococcal disease (IPD) among vaccinated and unvaccinated individuals aged <2, 2-4, 5-17, 18-49, 50-64, and >or=65 years old. The model was parameterized using published US surveillance data, supplemented with data from published literature.

The impact of indirect (herd) protection on the cost-effectiveness of pneumococcal conjugate vaccine.

Background: The heptavalent pneumococcal polysaccharide-protein conjugate vaccine (PCV7) confers protection against invasive pneumococcal disease (IPD) caused by serotypes that are responsible for substantial morbidity and mortality throughout the world. In 2000, the 7 serotypes covered by PCV7 accounted for 80% to 90% of serotypes isolated from the blood or cerebrospinal fluid of children aged <6 years in the United States. A previous review of the literature spanning the years 1998 to 2005 pertaining to the incidence of IPD among nonimmunized individuals in countries with universal PCV7 immunization suggested an indirect protective effect (herd protection, or community immunity) after widespread vaccination.

Indirect effects associated with widespread vaccination of infants with heptavalent pneumococcal conjugate vaccine (PCV7; Prevnar).

Prevnar (heptavalent pneumococcal conjugate vaccine; PCV7) provides protection against invasive pneumococcal disease (IPD) caused by vaccine serotypes. Indirect protection of non-immunised individuals may be the consequence of decreased transmission of vaccine serotypes, generally carried in the nasopharynx of infants and young children. This review summarises published reports of IPD incidence (1998-2005) among non-immunised individuals in countries with universal PCV7 immunisation.

Cost-effectiveness of pneumococcal conjugate vaccine: evidence from the first 5 years of use in the United States incorporating herd effects.

Background: Pneumococcal conjugate vaccine (PCV) has been in routine use in the United States for 5 years. Prior U.S.

Population-wide benefits of routine vaccination of children against influenza.

Using a stochastic simulation model of influenza transmission, clinical illness, and economic costs, we estimated the population-wide benefits of routinely vaccinating US children (ages 6 months to 18 years) against influenza. Disease burden was projected to decline as a result of both reduced susceptibility to infection among vaccinees and reductions in disease transmission to others in the community. Vaccination of 20% of children would reduce the total number of influenza cases in the US by 46%; 80% coverage would reduce the total number of cases by 91%.

Economic impact of respiratory syncytial virus-related illness in the US: an analysis of national databases.

Objective: To determine the impact of respiratory syncytial virus (RSV) infection on healthcare resource use and costs in the US from the third-party payer perspective.

Design: The study retrospectively analysed cross-sectional medical encounter data from three federally funded databases that comprise nationally representative samples of hospital inpatient stays, physician office visits and visits to hospital outpatient departments and emergency rooms.

Methods: Identification of RSV infection-related medical encounters was based on the occurrence of RSV-specific International Classification of Diseases (9th Edition)-Clinical Modification diagnosis codes (079.

A pharmacoeconomic evaluation of seven-valent pneumococcal conjugate vaccine in Spain.

Background: Streptococcus pneumoniae is a leading cause of illness in children. Seven-valent pneumococcal conjugate vaccine (PCV-7), recently approved in the United States, is the first vaccine to provide protective immunity against pneumococcal disease in children under the age of 2. PCV-7 is nearly 100% effective in preventing invasive pneumococcal infections and has been shown to significantly decrease the incidence of pneumonia and otitis media.

A pharmacoeconomic evaluation of 7-valent pneumococcal conjugate vaccine in Canada.

The objective of this study was to evaluate the projected health benefits, costs, and cost-effectiveness of pneumococcal conjugate vaccination for infants and children aged <5 years in Canada. A health state model incorporating incidence, vaccine efficacy, costs, and transitional probabilities for the health states (well, meningitis, bacteremia, otitis media, pneumonia, and death) was constructed for a 10-year time horizon. Implementation of a pneumococcal conjugate vaccine program in Canada for each annual birth cohort of 340,000 persons observed over 10 years would be expected to save approximately 12 lives and 100,000 cases of pneumococcal disease over 10 years, resulting in total savings of $67 million (Canadian dollars [Can$]).