With another flu season upon us and the H1N1 ("swine flu") virus looming large in our imaginations, we are in the midst of another predictable conversation over the merits of public vaccination programs. Vaccination is one of those thorny issues, like evolutionary theory, where the controversy in public opinion is far greater than is warranted by the controversy in expert opinion.
I am not a medical doctor, so I will refrain from making specific recommendations about what you should do, other than to say that it is wise to consult with your family doctor and/or public health authorities before making a final decision. However, what I can offer is an expert opinon about some psychological biases that may evoke reluctance to be vaccinated. Only with clear recognition of these biases can we attempt to make rational and appropriate health decisions.
Chief among these biases is illusory superiority. Research shows that the average person tends to think that he or she is better than average on nearly all traits: intelligence, generosity, athleticism, driving skill, etc. Like the children of Garrison Keillor's Lake Wobegon stories, a majority of the population will rank themselves higher than the average of the population when asked about their personal attributes.
(Of course, it is by definition impossible for this to reflect reality, assuming we use the most robust statistical indicator of central tendency -- i.e., the median, or 50th percentile, score.*)
The same type of inflated estimates appear for self-perceptions of immune system strength: in other words, the average person thinks he's healthier than the average person (Hoorens and Harris, 1998). If people view vaccination as something necessary only for high-risk and/or immunocompromised groups, the danger of illusory superiority becomes quite clear: very few people will readily identify a personal need for vaccination.
I think that many media outlets are overselling the case for vaccination by discussing the H1N1 strain in terms of its potential deadliness. Since a young Toronto boy died Monday from the H1N1 flu, the local news has been flooded with frightening stories about the disease. Fear keeps us watching, but fear also tends to confuse us.
Worse, television and Internet media give undue attention to fearmongers who raise questions about the dangers of vaccination. Certain popular radio commentators in the United States have been giving credence to concerns that the flu vaccine may be deadly in its own right. They claim that they will refuse vaccination, implicitly encouraging their listeners to do the same. (Of course, the unspoken fact is that these same commentators -- if they indeed keep their promises -- have teams of personal doctors at their disposal. The teeming masses in their audiences cannot afford such luxuries.)
A number of anecdotal reports have also emerged about people becoming ill after being vaccinated. These reports are spreading like wildfire across the Internet, and have led many to speculate that the vaccine is the cause of the illness. This betrays another common cognitive bias: the human mind is wired to seek out patterns of causation, and as a consequence illusory correlations can emerge. The same process explains why people think that washing their cars causes rainstorms or that magnetic bracelets cure arthritis pain. The truth is that influenza vaccines are specifically designed to make transmission of influenza by the vaccine impossible. When severe adverse reactions do occur after vaccination, they are very often the result of an entirely separate health problem.
Were I to frame the media conversation, I would argue for vaccination on the grounds of lost productivity rather than lost lives. H1N1 isn't likely to kill you, but it is likely to take you off your feet for a while. In these rough economic times, many people cannot afford to lose a week's pay because they catch the flu or because they need to nurse their sick children back to health.
While the decision whether or not to get vaccinated is a personal one, it is wise to keep in mind that your decision could have profound consequences for other people as well. Perhaps you have Wolverine-like regenerative abilities that will speed your recovery, but even if you remain asymptomatic you may pass the virus to others -- friends, family, colleagues, neighbours -- who are not so lucky. Where pandemics are concerned, it is wise to have a communitarian spirit.
For what it's worth, my wife just got diagnosed with the flu today. We're not entirely sure what strain it is, but we're not panicking. She's taking time off work, and I plan to be vaccinated when my turn comes around next week. (As the saying goes, a microgram of prevention...) Until then, we'll be extra careful about practicing habits that prevent contagion -- washing our hands frequently, preparing meals separately, and so on. H1N1 may be a new strain of flu, but there is nothing new about the best practices to control its spread.
Have a happy and healthy Halloween!
* Note: Technically, it could be possible if the population distribution is negatively skewed and we use a more sensitive indicator of central tendency such as the arithmetic mean. Consider the situation where Abe has $10, Billy has $15, and Cathy has $2. In this case, 2/3 of the population has more money than the arithmetic mean of $9. ($15 + $10 + $2 = $27 and $27/3 = $9) However, many important physical and psychological characteristics in humans have standard normal population distributions -- i.e., symmetric "bell curves".
Reference
Hoorens, V., & Harris, P. (1998). Distortions in reports of health behaviors: The time span effect and illusory superiority. Psychology & Health, 13, 451-466.
PHOTO CREDIT: http://www.rense.com/1.imagesH/vaccs_dees.jpg
