CDC switches emphasis to track adolescent vaccination rates

Local public health officials are warning that a change in the type of data collected by the Centers for Disease Control and Prevention's National Immunization Survey may hamper efforts to get young children vaccinated, particularly in large cities.

"This is a step backwards," said Jeffrey S. Duchin, MD, chief of communicable disease control, epidemiology and immunization for the Seattle and King County Public Health Dept. in Washington state.

While the CDC tracks childhood immunization rates by state, it also has done separate tracking for 22 large cities. But budget limitations, combined with a new emphasis on adolescent immunizations, are prompting the CDC to reduce that number to six. Resources will in turn be redirected to chart the teens who are receiving the growing number of shots recommended for their age groups.

The agency's National Immunization Survey has paid particular attention to cities since 1994 because urban areas tend to be home to a higher number of unvaccinated children.

Some experts maintain these data are vital to keeping vaccination rates high, assessing whether campaigns are working and determining what populations need increased attention. They also say the information provided by the statewide surveys, which are continuing, will not provide enough detail to be useful at the local level.

"We're bigger than most states. This is information that we need," said Jonathan Fielding, MD, MPH, director of public health and health officer for the Los Angeles County Dept. of Health Services. "We need the data to help focus on particular populations and communities. We can't take our eye off the ball. Let's keep this information flowing."

But while there is wide agreement that reducing the surveys' focus on urban toddlers is a regrettable decision, there was also agreement that surveying teens was a timely idea.

"The paucity of adolescent immunization rate data is so glaring. We don't even have the baseline data for adolescents," said Amy B. Middleman, MD, MPH, an adolescent medicine specialist at Texas Children's Hospital in Houston. She is also the Society for Adolescent Medicine's liaison to the CDC's Advisory Committee on Immunization Practices.

"This information is critical, but I would like to collect it without harming the information that's already being collected for young children," Dr. Middleman said.

Historically, teenagers have not been targeted by vaccination efforts, but that recently has begun to change. Three shots have been approved for this age group within the past couple of years. More are expected. And the ACIP voted to split the adolescent schedule from the child schedule at its meeting in October.

Public health officials say what they now need is data on both toddlers and teens.

"We've been forced into a choice here because of funding limitations, but both should be done" said Patrick Libbey, executive director of the National Assn. of County and City Health Officials. "There's another cohort of 2-year-olds every six months, but there's also a need for better data on adolescents."