The medic wielding the tiny smallpox vaccination needle jabbed my left arm a dozen times. Satisfied with his handiwork, he slapped a large butterfly bandage over the brand-new sore and gave me a stack of replacement bandages. I had to keep the vaccination covered, to aid the healing process. The last bandage came off three days before I flew to Iraq.

Once upon a time, the World Health Organization thought smallpox would be eradicated. We no longer believe that fairy tale, so military, emergency response and medical personnel now get smallpox vaccinations. Here's why: Despots, crooks and madmen invoking the wrath of God value weapons that kill en masse. Bacteria and viruses fit that bill, and packed as bio-weapons are much cheaper to produce than a nuclear bomb. Smallpox used to kill humans by the millions, and now we fear it could do so again.

However, the United States stopped mass inoculations for smallpox in the 1970s. Most young Americans are unvaccinated. When I pressed one of the doctors about the possibility of "shedding" vaccine and infecting an unvaccinated child, he assured me the chance of that was infinitesimally small. But he was also uncomfortable with the larger issue of societal vulnerability. "At some point, we need to start inoculating everyone again," he said. "It's the smart thing to do."

One expert told me that America probably has a high degree of "herd immunity" against smallpox — a statistically significant slice of the American population retains enough immunity to blunt the spread of the disease.

Still, relying on herd immunity instead of human intelligence is a poor way to defend against smallpox, or for that matter, any disease, including the flu.

Our vaccine production system, however, is flimsy. Moreover, our ability to "surge" vaccine production (in the event of a bio-attack or pandemic) is even weaker.

Witness the sudden shortage of flu vaccine with flu season less than 60 days away. Two companies, Chiron Corp. and Aventis Pasteur, manufacture America's flu vaccine. Last week, the British government shut down Chiron after regulators discovered bacterial contamination in its vaccines and other problems in the manufacturing process.

The regulators were doing their job, but the shutdown has knocked out half of America's flu vaccine supply.

Flu vaccine preparation is a tough business, for many reasons. Despite advances in gene-splicing techniques, most flu vaccine is produced using chicken eggs as a culture medium. The process takes six months to produce vaccines, so manufacturers have to make several tricky calls. In order to make an effective vaccine, they have to make some astute guesses regarding the genetic characteristics of the flu strain — there are new flus every year. They must also predict demand for the vaccine. The Wall Street Journal reported that several pharmaceutical companies quit the U.S. flu-vaccine market because forecasting demand is so difficult. Companies cannot afford to be left with several million unused (and unsold) vaccine doses.

Flu vaccines aren't the only problem — fragility is endemic to the entire vaccine industry. In 2002, the Government Accounting Office issued a report that said in 1967, 26 companies made children's (pediatric) vaccines. In 2004, only five are in the business, and for some specific vaccines, there are only one or two suppliers.

Slender profit margins are one reason manufacturers avoid the pediatric vaccine market. Manufacturers also fear multimillion-dollar lawsuits filed on behalf of those who suffer negative reactions to vaccines, and negative reactions are a statistical certainty.

The flu vaccine shortage ought to jolt human intelligence. I don't expect another Great Plague this winter, but the flu epidemic of 1918-1919 did kill well over 20 million people.

This is an issue we must address now.

The Centers for Disease Control and Prevention says there are simply too few manufacturers, and the CDC's director, Julie Gerberding, argues that the U.S. government may have to offer "incentives" to companies to produce vaccines. Those might take the form of tax credits for investment in new manufacturing processes (e.g., cell culture), immunity from vaccine related lawsuits or a guaranteed market for unused vaccines.
