CDC: Death toll is rising for influenza

New data underscore need for HCW vaccines

Death rates from influenza are rising with the aging of the U.S. population, and the virus now kills an average of 36,000 people a year, according to the Centers for Disease Control and Prevention (CDC). The new data underscore the need to protect vulnerable patients from nosocomial spread by vaccinating health care workers, public health experts say.

While healthy individuals may regard the flu as just a nuisance or a bad cold, the virus can lead to dangerous complications in the elderly or immune-compromised, notes Keiji Fukuda, MD, MPH, chief of the epidemiology section of CDC’s influenza branch. In fact, it is "one of the major infectious disease causes of death in the country," he says.

The CDC researchers combined virus surveillance data and national mortality data to reach the new estimates for influenza deaths, findings that were reported in the Jan. 8 issue of the Journal of the American Medical Association. Previously, the CDC had estimated that an average of 20,000 influenza-related deaths occurred each year. While mild years may result in few flu-related deaths, in a severe flu season, the deaths could be as high as 70,000. Some 90% of those deaths occur among people who are 65 or older.1

"They’re really breathtaking numbers," Fukuda says. "We really have approached it in a conservative way." The prevalence of a more virulent strain, AH3N2, in the 1990s, contributed to the rise in deaths. Each year the flu vaccine is reconfigured based on strains that are circulating worldwide. "When you look at the impact of influenza, or you look at the epidemiology of influenza, this variability is one of the characteristics that we see for this disease," he says.

Along with the elderly and chronically ill, health care workers are a priority target for the vaccine. However, only about 38% receive it, according to the 2000 National Health Interview Survey. Health care workers may harbor some of the myths that are common about flu vaccination. For example, some may believe that it’s possible to get the flu from the vaccine, says Fukuda.

But the greater challenge is making vaccination programs accessible, he says. A single, annual campaign isn’t sufficient. Vaccinations should continue even after the major push in October or November, he says.

"For a lot of reasons, which are not so clear, a lot of health care workers believe that after sometime in October or early November, it’s time to stop giving flu vaccine," Fukuda says. "That’s a mindset that we’re really trying to change.

"No matter how big the push is, there are always people who don’t get vaccinated. To continue with those activities afterward is an important lesson."

References

1. Thompson WW, Shay DK, Weintraub E, et al. Mortality associated with influenza and respiratory syncytial virus in the United States. JAMA 2003; 289:179-186.

2. Centers for Disease Control and Prevention. Prevention and control of influenza: Recommendations of the Advisory Committee on Immunization Practices. MMWR 2002; 51 (RR03):1-31.