An assessment of the screening method to evaluate vaccine effectiveness: the case of 7-valent pneumococcal conjugate vaccine in the United States.

The screening method, which employs readily available data, is an inexpensive and quick means of estimating vaccine effectiveness (VE). We compared estimates of effectiveness of heptavalent pneumococcal conjugate vaccine (PCV7) against invasive pneumococcal disease (IPD) using the screening and case-control methods. Cases were children aged 19-35 months with pneumococcus isolated from normally sterile sites residing in Active Bacterial Core surveillance areas in the United States.

Use of surveillance data to estimate the effectiveness of the 7-valent conjugate pneumococcal vaccine in children less than 5 years of age over a 9 year period.

Background: Case-control studies evaluating post-licensure effectiveness of conjugate vaccines can be laborious and costly. We applied an indirect cohort method to evaluate the effectiveness of seven-valent pneumococcal conjugate vaccine (PCV7) against invasive pneumococcal disease (IPD) and compared the results to the effectiveness measured using a standard case-control study conducted during the same time period.

Methods: IPD cases among children 2-59 months old were identified through the Active Bacterial Core surveillance system during 2001-2009.

Impact of USA300 methicillin-resistant Staphylococcus aureus on clinical outcomes of patients with pneumonia or central line-associated bloodstream infections.

Background: The USA300 methicillin-resistant Staphylococcus aureus (MRSA) strain, which initially emerged as a cause of community-associated infections, has recently become an important pathogen in healthcare-associated infections (HAIs). However, its impact on patient outcomes has not been well studied. We evaluated patients with invasive MRSA infections to assess differences in outcomes between infections caused by USA100 and those caused by USA300.

Invasive pneumococcal disease and pandemic (H1N1) 2009, Denver, Colorado, USA.

Pneumococcal pneumonia was a complication during previous influenza pandemics but was not evident initially during pandemic (H1N1) 2009. During October 2009 in Denver, Colorado, USA, invasive pneumococcal disease (IPD) and pandemic (H1N1) 2009 peaked simultaneously, which suggests a link. We compared cases of IPD in October 2009 with cases in February 2009, the most recent peak month of seasonal influenza.

Prevention of antibiotic-nonsusceptible Streptococcus pneumoniae with conjugate vaccines.

Background: Streptococcus pneumoniae (pneumococcus) caused approximately 44000 US invasive pneumococcal disease (IPD) cases in 2008. Antibiotic nonsusceptibility complicates IPD treatment. Using penicillin susceptibility breakpoints adopted in 2008, we evaluated antibiotic-nonsusceptible IPD trends in light of the introductions of a 7-valent pneumococcal conjugate vaccine (PCV7) in 2000 and a 13-valent pneumococcal conjugate vaccine (PCV13) in 2010.

Revisiting the need for vaccine prevention of late-onset neonatal group B streptococcal disease: a multistate, population-based analysis.

Background: Intrapartum antibiotic prophylaxis for neonatal group B streptococcal disease (GBS) effectively prevents disease among infants <7 days old, but there are no prevention strategies for late-onset GBS disease (onset on days 7-89 of life). We describe trends in late-onset GBS over a 16-year period to characterize disease burden and estimate vaccine preventability.

Methods: We conducted active, population-based surveillance for invasive late-onset GBS disease in 10 states from 1990 to 2005.

Population snapshot of emergent Streptococcus pneumoniae serotype 19A in the United States, 2005.

Background: Serotype 19A invasive pneumococcal disease (IPD) increased annually in the United States after the introduction of the 7-valent conjugate vaccine (PCV7). To understand this increase, we characterized serotype 19A isolates recovered during 2005.

Methods: IPD cases during 1998-2005 were identified through population-based surveillance.

Effectiveness of seven-valent pneumococcal conjugate vaccine against invasive pneumococcal disease: a matched case-control study.

Background: When seven-valent pneumococcal conjugate vaccine was introduced in the USA, many children were vaccinated on schedules that differed from those tested in clinical trials. Our aim was to assess the effectiveness of the vaccine against various pneumococcal serotypes, and to measure the effectiveness of the recommended dose schedule and of catch-up and incomplete schedules.

Methods: Invasive disease, defined as isolation of pneumococcus from a sterile site, was identified in children aged 3-59 months through the US Centers for Disease Control and Prevention's Active Bacterial Core surveillance.