Session: Slide Session: Pediatric Vaccines
Tuesday, October 28, 2008: 12:00 AM
Room: Room 151B
Background: The implementation in February 2006 of routine rotavirus vaccination of US infants makes it imperative to rapidly assess vaccine uptake and impact of vaccination on the health burden of rotavirus and prevalence of circulating strains. Methods: Vaccine uptake is being assessed using data from six sentinel immunization information systems (IIS). Vaccine impact is being examined using data from national and state databases on diarrhea and rotavirus hospitalizations and emergency room visits and reports of rotavirus detections from a national network of sentinel laboratories. Strains are being characterized from rotavirus-positive specimens obtained from a subset of these laboratories. Results: By late 2007, >10 million doses of rotavirus vaccine had been distributed in the United States and 50%-67% of infants 3 months of age at IIS sites had received at least one vaccine dose. Coverage with full 3-dose vaccine series ranged from 27%-45% at 7 months of age and 18%-32% at 13 months of age. By March 2008, mid way through the winter 2007-spring 2008 rotavirus season, onset of rotavirus activity had been delayed by up to 2-3 months across the country. Furthermore, the vast majority of sentinel laboratories nationwide have reported declines in rotavirus detections of >60%-70% compared with data from the same months during the 7-8 years prior to vaccine implementation. More than 85% of rotavirus strains circulating during 1996-2007 contain antigens that are included in the licensed vaccines; data for 2007-2008 are awaited. Conclusions: With relatively modest levels of vaccine uptake, marked delays in onset of rotavirus activity and reductions in rotavirus detections have been reported early in the 2007-2008 rotavirus season. Monitoring is ongoing to assess disease activity through the full season and to determine whether the observed changes in disease activity can be attributed to vaccination.