The mandatory shot has drawn fire from unions, civil libertarians and some scientists. It is the scientific concerns that ought to give administrators pause, since the evidence backing the efficacy of the flu vaccine is far weaker than either the government or most public health officials like to admit.
A report issued last fall by the University of Minnesota's Center for Infectious Disease Research & Policy, whose expert panel included a number of leading public health scientists and drug industry representatives, concluded that existing vaccines are far from adequate in providing “herd immunity” for vulnerable populations. The CIDRAP report also found that calls for universal vaccination—the CDC now recommends annual vaccination for everyone over 6 months of age—“have not always used state-of-the-art scientific data.”
The report cited at least 30 examples of government agencies and medical societies exaggerating the benefits of the vaccine. Brochures claim that the vaccine protects against flu in 70% to 90% of adults who receive it; official documents state 50% of deaths among the elderly could be prevented with universal vaccination. (The CDC estimates 89% of the 731,831 people who died from flu between 1976 and 2007 were over 65.)
Yet that's not what the evidence says. Most years, because the precise genetic makeup of the predominant flu strain cannot be known when the vaccine is developed, inoculation provides immunity in slightly more than half the people who receive the shot. This year, because the match was pretty solid, the CDC estimates efficacy at about 62%.
How much protection is afforded patients in a doctor's office or hospital if nearly 4 out of every 10 workers, even if inoculated, may be carrying the virus?
Last week, I spoke with Dr. Michael Osterholm, one of the primary authors of the CIDRAP report. He backs calls for universal vaccination. But he opposes firing people over the issue because it ignores the fact that consistent protection remains elusive for the present generation of vaccines. “If I fix 9 of the 10 screen doors in my submarine, it's still going to sink,” he told me.
There may even be risks associated with making flu shots mandatory. Healthcare workers, who are prone to the same misconceptions about the efficacy of the vaccine as the general population, may think they needn't take other precautions to prevent the spread of infection within their facilities if they have had a flu shot. They include proven disease-prevention steps such as frequent handwashing, avoiding direct contact with patients with flu symptoms and limiting visitation at hospitals.
In other words, a reasonable alternative to mandatory vaccination is integrating voluntary campaigns encouraging 100% compliance into a comprehensive program aimed at eliminating all infectious disease transmission—at least until a better vaccine comes along.
Merrill Goozner, Editor