Vaccination rates stall

Despite a global flu pandemic, American adults are not being vaccinated against the flu any more than they were a year ago, a new study showed last week.

That news from research organization RAND Corp. came just a day before Centers for Disease Control and Prevention Director Thomas Frieden reported that roughly 15% of Americans, or one in six persons, have been infected with the deadly H1N1 flu virus—popularly referred to as swine flu—since the strain emerged in the U.S. seven months ago. In a news conference on Dec. 10, Frieden also estimated that there have been nearly 50 million cases, more than 200,000 hospitalizations and about 10,000 deaths from this strain. Of those estimated deaths, Frieden said, about 1,000 were young children and about 7,500 were young adults.

Given these recent estimates from the CDC, it’s perhaps too early to get a sense of how much these hospitalizations cost. The American Hospital Association, Healthcare Financial Management Association and Agency for Healthcare Research and Quality did not have a cost breakdown for flu-related hospitalizations. But even with these events, combined with heightened awareness about H1N1 and other flu strains, the American public seems to be responding to flu season as they have in the past. By the middle of November, about 32% of all U.S. adults and 37% of adults recommended to receive a flu vaccination had been inoculated against the flu, RAND researchers reported. (For information on flu-tracking technology, see story, p. 33.)

The study also said that 17% of all adults and 19% of those recommended for vaccination intended to receive the seasonal flu by the end of the vaccination season. Data were based on a nationally representative survey of more than 5,600 adults age 18 and older during the middle of November.

Among unvaccinated adults who did not intend to be vaccinated against the seasonal flu, about one in five said they thought they did not need the vaccine, the study showed. Another one-fifth said they do not believe in flu vaccines, and slightly less than one-fifth said they were concerned about getting sick or experiencing side effects. One positive change from last year’s flu season is that adults began getting the seasonal vaccine earlier this year.

“Seasonal vaccine uptake in September was almost three times higher in 2009 than 2008, indicating the vaccination season got off to an earlier start in 2009,” the study said. “By the end of October 2009, the cumulative uptake of seasonal influenza vaccine exceeded last year’s rate by roughly 7 percentage points.”

Meanwhile, healthcare workers were the most likely to be vaccinated among adults specifically recommended to receive the vaccine. “However, fewer unvaccinated healthcare workers intended to receive the vaccine than others for whom it is recommended,” the study said.Morbidity and Mortality Weekly Report—released on the same day as the agency’s flu news conference—that showed the H1N1 mortality rate for American Indians and Alaskan Natives was four times higher than persons in all other racial/ethnic groups combined. According to the report, the states of Arizona and New Mexico observed a disproportionate number of deaths in that group in October. (The CDC groups statistics for those two populations together.)

As a result of this finding, representatives from 12 state health departments, the Council of State and Territorial Epidemiologists, tribal epidemiology centers, the Indian Health Service and the CDC formed a working group to compile data on death rates. The results showed that from April 15 until Nov. 13, American Indians and Alaskan Natives in the 12 participating states had a mortality rate that was four times the rate of other racial and ethnic populations combined.

“Reasons for this disparity in death rates are unknown and need further investigation,” the report said, “however, they might include a high prevalence of chronic health conditions (e.g., diabetes and asthma) among AI/ANs that predisposes them to influenza complications, poverty (e.g., poor living conditions) and delayed access to care,” it said, adding that there needs to be increased awareness among the American Indian and Alaskan Native population and their healthcare providers about the potential severity of the flu and the timely use of anti-viral medications. “Efforts to promote the use of 2009 H1N1 influenza monovalent vaccine in the AI/AN populations should be expanded,” the study also said.

Jay Wenger, associate director for science in the CDC’s Arctic Investigations Program, emphasized this last point. He worked on a separate report this fall that studied influenza-related hospitalizations in Anchorage hospitals from Sept. 1 through Oct. 21. Hospitalization rates were highest among American Indians and Alaskan Natives.

“This is still a good window of opportunity to be vaccinated,” Frieden said in last week’s news conference. “I can understand people who say that there has been so much and now it’s going down—but we don’t know what’s going to happen,” he added.

What do you think?