Tuesday, March 18, 2008

Utilization of Rotavirus Vaccine by Immunization Providers in Los Angeles County

Alvin Nelson El Amin1, Jon La Mori2, and Susan Ashkar2. (1) Immunization Program, County of Los Angeles Department of Public Health, 3530 Wilshire Blvd, Suite 700, Los Angeles, CA, USA, (2) Immunization Program, Los Angeles County Department of Public Health, 3530 Wilshire Blvd., Suite 700, Los Angeles, CA

Learning Objectives for this Presentation:
By the end of the presentation, participants will better understand provider usage patterns of the currently licensed rotavirus vaccine in Los Angeles County.

On February 3, 2006, eight years after a previously licensed rotavirus vaccine was withdrawn from the US market because of an association with intussusception, the US Food and Drug Administration licensed a pentavalent rotavirus vaccine (RotaTeq®) for use in infants. Since licensure of the current vaccine, there have been concerns about the level of its use by immunization providers. Additionally, on February 13, 2007, the vaccine's manufacturer updated the package insert to include post-marketing reports of intussusception among vaccinees, although there appeared to be no cause-and-effect relationship.

Assess the level of rotavirus vaccine usage by immunization providers in Los Angeles County.

The Regional Immunization Registry (LINK) was utilized to determine the number of first doses of rotavirus vaccine administered by providers, as a proportion of first doses of DTaP (1stRota/1stDTaP), broken down by month and provider type (public versus private).

The 1stRota/1stDTaP exceeded 50% for both types of providers after three months of vaccine availability, and exceeded 70% by the end of the 15 month study period. In the eighth month of the study period, an 11% decrease in 1stRota/1stDTaP for private providers was noted, possibly, the result of a revision to the LINK dose-forecasting algorithm for this vaccine. Additionally, three months after the vaccine manufacturer changed its package insert, another 11% decrease in 1stRota/1stDTaP was noticed among private providers.

Generally, immunization providers in Los Angeles County showed rotavirus vaccine usage patterns consistent with expectations for a new vaccine. A significant decrease in vaccine usage by private providers occurred near the end of the study period, and could have resulted from the vaccine's manufacturer changing its package insert.