From the WSJ's always thought-provoking Sharon Begley. This column is so interesting I'm going to post a big chunk of it:
You have 100 doses of a vaccine against a deadly strain of influenza that is sweeping the country, with no prospect of obtaining more. Standing in line are 100 schoolchildren and 100 elderly people.
The elderly are more likely to die if they catch the flu. But they also have fewer years left to live and don't get out enough to easily spread or catch the disease. The kids are more likely to act like little Typhoid Marys, sneezing virus over anyone they encounter, and have almost their whole life ahead of them. But they're also less likely to die if they get sick.
Whom do you vaccinate?
This dilemma is haunting experts concerned that avian influenza might start spreading from person to person instead of (as far as we know) mainly from birds to people. But it also applies to regular old flu, which always has the potential to reach pandemic proportions. In response, studies now are shedding light on the ethical issues and the most effective strategy for reducing illness and death if vaccine must be rationed. Sadly, they make a pretty good case that current U.S. policies leave a lot to be desired.
First, ethics. In May, scientists at the National Institutes of Health stirred things up with a paper calling into question the policy that aims to save the most lives by first vaccinating the old, the very young and the sick, putting last those who are two to 64 years of age.
The value of a life, they argued, depends on age. A 60-year-old has invested a lot (measured by education and experience) in his life, but has also reaped most of the returns. A child has minimal investment. A 20-year-old has great investment but has reaped almost none of the returns. Conclusion: To maximize investment in a life plus years of life left, 13- to 40-year-olds should have first claim on rationed vaccine, explains NIH's Ezekiel Emanuel.
Second, efficacy. Let's leave aside the fraught question of the value of a life. Evidence keeps accumulating that vaccinating the elderly might not even be the best strategy for minimizing deaths. The reason is that during some flu pandemics, the mortality rate among the elderly is hardly higher than during nonpandemic years. The flu certainly kills some old people, says Dr. Emanuel, but many would have died anyway. In addition, they may not benefit from flu vaccines as much as is assumed: A 2006 study found that the antibody response by people over 65 is less than half that in young adults.
Critics reply that the elderly are more likely to die if they get the flu, so ethics requires you protect them, the most vulnerable, first. Indeed, in the 1957 and 1968 pandemics, the very young and very old had the highest flu-mortality rates. But in the 1918 pandemic, 20- to 40-year-olds and children under five had the highest mortality rate. The elderly were more likely to either not become infected or to survive if they did, perhaps because only someone with a sturdy immune system lived to a ripe old age back then.
The common-sense notion that vaccinating the elderly is the best way to save the elderly also deserves scrutiny, according to a study this week in the journal PLoS Medicine. Infants and the elderly don't spread the flu as much as, say, a schoolchild or business traveler. Might you decrease both illness and death, including among the old, by vaccinating other age groups first?
As it happens, that is what doctors did in Tecumseh, Mich., in 1968. They vaccinated school-age kids, whose lower natural immunity and many contacts (not to mention a tendency to sneeze all over the place) makes them high transmitters of infectious disease. That tactic slowed the spread of disease and cut the death rate from flu to below that in a matching community.
So, who do we vaccinate first? For me, this is a clear case of my moral intuitions - vaccinate the most vulnerable first (the elderly) - contradicting the empirical evidence (it's actually better to vaccinate the kids first). Help me out here readers.
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Added to the above dilemma, is the fact that if the expected mutation of the current H5N1 virus, is to follow the 1918 pandemic, it is likely to use the victims own immune system for its attack.
It tricks the immune system to virtually "liquidise" the lung tissue of the host body, so that the victim dies by "internal drowning".
The stronger the host body's immune system, the more likely it is for death to occur.
During the 1918 pandemic, the majority of deaths occurred in the age range of 13 years to 30 years.
The-Best-Bird-Flu-Blogs-Team.
www.birdflubreakingnews.com
I'm going to completely ignore the prickly question of ethics and jump to the issue of efficiency. The effect of vaccination will depend on a host of factors: how effective the vaccine is, how many doses you have, how it will be desemminated (such as randomly throughout the population or targeted around cases), the age makeup of the population, whether you are early or late into the epidemic etc. etc. If your vaccine protects more against death rather than preventing transmission, vaccinating the elderly may make more sense. If you have a lot of doses and can get a herd immunity effect that will protect the elderly from disease/death (big if), you might want to vaccinate kids. If you catch the epidemic early enough (another big if), it might make the most sense to vaccinate the people who are the highest transmitters who have had contact with your initial cases. The long and the short of it is that there isn't a single answer. Also it should be understood that what is most appropriate can also change as the epidemic goes on.