During the 2003-2004 flu season, only 12 percent of children between the ages of 2 and 8 in the U.S. received both doses of the trivalent inactivated influenza vaccine (TIV) that are recommended for adequate protection, according to findings from the Vaccine Safety Datalink study.
The Vaccine Safety Datalink project is a population-based study of children enrolled in health maintenance organizations across the United States.
Data for 125,928 children between 6 months and 8 years, receiving TIV for the first time, were analyzed by Dr. Lisa A. Jackson of the Group Health Center for Health Studies in Seattle, Washington, and colleagues with the project.
The researchers looked at compliance rates during three seasons: 2001-2002, 2002-2003 and 2003-2004, according to their report in the November issue of Pediatrics.
Among children aged 6-23 months, administration of both doses was achieved in 44 percent in the first season, 54 percent in the second season and 29 percent in the most recent season analyzed.
However, among children between the ages of 2 and 8, the second dose was given to 15 percent during the first year, 24 percent during the second year and only 12 percent in the most recent time period.
Jackson’s team found that children who received their first TIV dose before mid-November had the highest compliance rates for full immunization. “This reinforces previous recommendations to target previously unvaccinated children less than 9 years of age for early vaccination, in September if possible,” the investigators say.