Last week, there was an interesting conversation about children vaccinces on the Diane Rehm show (podcast here). There was a bushel of good stuff said, but I found the conversation strangely dogmatic and un-informative. While I'm all in favor of the use of immunizations to protect people from diseases, I think it's important to acknowledge how competing opinions come about and when they are pragmatic. This conversation did not seem to do that.
There was a question raised about the strength of immunity induced by vaccines compared to natural infection. A blanket response was given that "vaccines are much more effective than the natural infections at protecting you and keeping you healthy", but little evidence was given in support of this conclusion. The example of measles was mentioned, which is a case where natural infection induces life-long immunity, potentially better than vaccination. In the case of whooping cough, our new vaccine seems to be worse than our old vaccine, but natural infection doesn't induce good immunity either. So, two examples, neither of which as a vaccine that works better than natural immunity. Some reference to age-dependent virulence in mumps and polio were also made, but without a clear purpose. The whooping cough (pertussis) situation was dismissed earlier in the show as "complicated", but no further explanation was given -- a skeptic might take this to be an intentional departure from impartial scientific discussion to bias the public understanding in favor of immunization. Perhaps the panelist was including the potential cost of disease in that comparision, in which case, many vaccines do come out on top.
The discussion did not explain how sometimes people's personal interests can differ from the public health interests of the nation. My own research1 and that of others has shown repeatedly that resistance to immunization programs IS RATIONAL when the diseases they prevent are rare. In practice, the diseases are NOT rare enough for this effect to kick in, but it's pretty easy to see how, based on personal experience and limited expertice, citizens can logically arrive at such a belief. It seems counter-productive not to acknowledge this. And it even seems inconsistent with the American ethos of individualism, where many value independence and the freedom of citizens to make their own chocices.
National public health recommendations blanket for the entire American population. While there is some effort to describe conditions and circumstances that may be outside the scope of the standard recommendations, the diversity of our nation is too great to be fully enumerated in any policy plan. We mostly leave it up to patients to discuss and decide with their doctors how to handle their special circumstances. That's good and should be encouraged. I think the actual catch is with the medical community, and how, in making recommendations, they choose to balance the interests of each patient with the public health interests of the community. I know, for example, that allot more young people are getting shingles than used to, and the shingles vaccine would probably be good for them, but the government recommendations are only for older people (50+).
There was a good deal of "Trust us. We're scientists." in the conversation. When the risk of autism was raised, the panellists stated that there's no connection between inoculations and autism. All the scientific literature I've personnally read exonerates vaccines, but no studies or references were cited. Similarly, the panelists punted on the question of whether or not our chickenpox vaccine is altering shingles rates, leaving things as "wait and see" rather than an open scientific question on which people may have different opinions.
Our scientific understanding of how innoculations and our immune systems in general work is still very incomplete. This gap and the associated uncertainty should be acknowledged and embraced, and is a good reason to embrace a diversity of immunization strategies in the general population within the bounds of what has been scientifically established. Science is about exploring the unknown -- by definition, scientists don't know what they are doing (or else, they aren't being very good scientists). This seemed to be particularly relevant to the discussion of the CDC immunization schedule for children. While much work has gone into this topic, it seems far from a settled issue, based on the naivety of methods employed in this story about the mathematics of schedual development. Tools like "Choose your own schedual" should be part of the discussion, if for no other reason than to explain their weaknesses.
The question of vaccine pricing was raised, and the panellists gave some informative answers. But it seemed like some answers were aimed at defending the status-quo. It will be interesting to learn more about vaccine prices, price-tiering, and supply security issues.