The Centers for Disease Control and Prevention (CDC) acknowledges a difference between flu death and flu-associated death yet uses the terms interchangeably, writes Peter Doshi. Statistical incompatibilities also exist between official estimates and national vital statistics data.
For example, CDC states that the historic 1968-9 "Hong Kong flu" pandemic killed 34,000 Americans. At the same time, CDC claims 36,000 Americans annually die from flu. What is going on, asks Doshi?
The CDC uses indirect modelling methods to estimate the number of deaths associated with influenza. Thus the much publicised figure of 36,000 is not an estimate of yearly flu deaths, as widely reported in both the lay and scientific press, but an estimate - generated by a model - of flu-associated death, he says.
Compounding these problems is a marketing of fear - a CDC communications strategy in which medical experts "predict dire outcomes" during flu seasons, he adds.
If passed, the Flu Protection Act of 2005 will revamp US flu vaccine policy. The legislation will require CDC to pay makers for vaccines unsold "through routine market mechanisms." The bill will also require CDC to conduct a "public awareness campaign" emphasising "the safety and benefit of recommended vaccines for the public good."
Yet Doshi believes that this bill obscures the fact that CDC is already working in manufacturers' interest by conducting campaigns to increase flu vaccination.
If flu is in fact not a major cause of death, this public relations approach is surely exaggerated, he says. Moreover, by arbitrarily linking flu with pneumonia, current data are statistically biased. Until corrected and until unbiased statistics are developed, the chances for sound discussion and public health policy are limited, he concludes.