Most people, when let alone, are not dumb. They can make reasonable decisions if given the right information. However, when people are part of large groups, somehow it seems, the IQ of an average individual, and even the effective IQ of the group as a whole, appears to decrease. Members of the group can then do really dumb things.

One such example of group stupidity is the case of Influenza vaccinations here in Israel.

A few weeks ago, by some sheer coincidence, a few elderly people who received flu shots died after being inoculated. After some investigation, it was concluded that the vaccinations had nothing to do with these unfortunate deaths. So, things should have been back to normal now. And people should have resumed getting their vaccinations.

This however is not the case. Listening to the car radio, I learned that the average number of vaccinations a day decreased from about 30000 to 10000, that is, a factor of three decrease. The net result is that 2/3's of the people who should have been vaccinated will not be. Why? Because they are afraid to die from getting vaccinated. A phantom fright. A case of mass hysteria. This of course will have detrimental effects, because the number of cases of people dying from flu complications will increase dramatically.

First, some statistics (mostly from here):

• About 2/3s of the elderly american population gets the flu vaccine each year.
• The number of deadly flu complications is about 36,000 per annum.
• Israel's population is about 42 times smaller than that of the US.
• Since more than a million (i.e. 1/7) of the Israeli population gets vaccinated, it is fair to assume that most of the elderly high risk population gets vaccinated, certainly more than the American 2/3's (my guesstimate would be about 80% or more).

Thus, most of the 36000 annul flu related deaths in the US are because 1/3 of the population is too lazy to get vaccinated. This means that by decreasing the vaccination rate in israel, from say 80% to 80%/3, the increased number of flu complications related deaths would be about 0.8*(2/3)/(1/3)*36000/42 ~ 1000 per year. (I took the liberty to round a little...). For comparison, even if the aforementioned deaths were related to the flu vaccine (and supposedly they aren't), we are still talking about a 2 orders of magnitude difference!

From the point of view of an individual: Since you are more likely to die if you don't get vaccinated, it is worth while to take the vaccine, period. This is especially so if you are an elderly individual.

From the point of view of an employer: Unlike most individuals who wont quantify life with money, employers do. However, even for an employer it is certainly worth while to vaccinate his (or her) employees. If about 10% of the population gets the flu each year, and each is incapacitated for a week, then a typical employer saves about 10% of a week's salary per vaccination. In Israel, the average weekly salary is about 500$. So, per vaccination (which costs about 10$), the employer saves on average 50$. Certainly a worth while investment.

What about the state? Here the situation is not that clear. A sick individual will contribute towards a lower GDP. However, dead elderly people (who didn't get vaccinated, because for example, they were hysteric about getting sick from the vaccination itself), cost significantly less money for the social services for example.

The lost GDP per capita is about 10% of 1/52 (one week) of the GDP per capita. In israel it would be about 38$ per year per individual (note that it is similar to the amount saved by the employer). So, for the whole 7,000,000 population, it is about 250 million $. The state however sees less than that. The total GDP of israel is about 130 billion dollars, while the tax revenue is about 45 billion dollars. Namely, for each dollar lost in GDP, the state tax revenue decreases by about 1/3 of that. So the reduced GDP would imply a lost tax revenue of about 80 million dollars.

On the other hand, if the typical person who would die of flu complications is in the last decade of his life (at least on average), then a rough guesstimate would be that each death case would imply a premature death by typically 5 years. Since the death rate in israel is 6.2 per 1,000 (or about a total of 40,000 a year), the 1000 premature deaths would reduce the life expectancy in israel, in 2006/2007 by somewhat more than a month, and with it relieve some of the burden on the state.

The 1000 premature deaths would save the social security services something of order 5000 person-year's worth of social welfare. If a person typically gets 1000$/month from the social security. This case of mass hysteria will save Israel's social security service something of order 60 million $.

In other words, the state would be close to break even - the amount of money it saves by not having to pay the social security benefits for old people would be of the same order as the amount lost by lower revenue. So it is not clear off hand whether the state is better off if people do or don't take the flu vaccine (well, leaving aside the question of a reduced life expectancy, quality of life, etc... which cannot be quantified with dollars, at least, not that easily).

So, what's the bottom line? First, it is evident that a group as a whole tends to do really stupid things. In this case, mass hysteria (which typically develops in groups with a few stupid yet loud individuals...) will cause a statistical death toll which is higher than the annual number of road casualties!

Also, if you're contemplating on whether to get vaccinated, then stop, and simply get it done with, it is a very high payoff investment. If you're an employer, consider vaccinating your employees. Your investment will definitely pay off as well. And if you decide not to get it, and die prematurely, at least society might benefit (also, it would imply that you die after a short, and relatively cheap hospitalizations, so there are other indirect benefits which we didn't discuss).