Who should get influenza vaccine?

May 16 2006

An American flu pandemic would present difficult and tragic choices: As many as 90 million people might become sick, and widespread shortages of vaccine would likely leave more than 90 percent of the population unprotected in the pandemic's first year.

When there is not enough medicine for all, how should government prioritize who gets the scarce doses first?

One seemingly obvious answer, and one endorsed by two federal committees, would be to ration the medicine in such a way as to save the most lives possible. But in a paper appearing in the May 12 issue of the journal Science, University of Vermont ethicist Alan Wertheimer, professor emeritus of political science and current visiting scholar at the National Institutes of Health, and Ezekiel Emanuel, head of the NIH's clinical bioethics department, argue for an alternative approach.

Attempting to save the most lives gives the oldest, youngest and sickest priority for vaccination. Guidelines from the National Vaccine Advisory Committee and the Advisory Committee on Immunization Policy, in fact, place healthy people aged 2 to 64 as the very lowest priority, below even funeral directors.

Emanuel and Wertheimer's distribution recommendations are different: they put healthy people from early adolescence to middle age toward the front of the line for vaccination. (Both sets of recommendations give first priority to frontline health-care workers and people involved in producing and distributing vaccine.) They argue for allocating scarce medicine by accounting for an individual's degree of investment in his or life, balancing that consideration with attention to life expectancy.

"The idea is that it's important to ask whose lives are they and at what point in life are they," says Wertheimer, who co-developed the UVM Honors College's first-year ethics curriculum before retiring last year. "There is a big difference between saving the most lives and the most life years."

He explains that a 20-year-old might have 65 years left to live; a 65-year-old, in contrast, might expect to live only 20 more years. To Emanuel and Wertheimer, it was not necessarily desirable to dedicate vaccines to sick retirees with few remaining life years at the expense of healthy college students. So they argue for an alternative approach, one partially based on what they call the "life-cycle principle."

The principle asserts that people should be permitted an opportunity to live through all stages of life, experiencing childhood, adolescence, a maturing career and family. From this perspective, the death of a child is more tragic than the death of an elderly person, not because older people are less important, but because the younger person has not yet had the opportunity to enjoy all of life.

But distributing vaccines solely to maximize years of life has problems of its own, chiefly because it would, if followed strictly, allocate all resources to infants. So Emanuel and Wertheimer argue that vaccine policy should also consider the amount an individual has invested in his or her life. A 20-year-old, they suggest, has developed more unfulfilled interests, plans and hopes than a baby and therefore deserves a higher priority for vaccine.

They also emphasize public order in their suggested vaccine-distribution priorities, giving vaccine priority to people in roles that help stanch the spread of disease. They say this actually reduce the overall death toll of an epidemic if it follows a trajectory similar to the 1918 outbreak rather than more recent epidemics.

Wertheimer concedes that making these kinds of calculations is extremely difficult and controversial.

"People don't like to ask the sorts of the questions in this paper," Wertheimer says. "It would be nice if we did not have to confront this issue. And we may not have to. But at some point, it seems likely that we may have to confront a pandemic or something else that poses a similar dilemma."