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Last Updated

22 Aug 2003

Source: New York Times, October 7, 2001


Fears of Anthrax and Smallpox

With potential biological terrorism looming large in the minds of government officials and a frightened public, attention has focused on two threats above all others: the germs that cause anthrax and smallpox. Both are hardy and highly lethal, making them good weapons for inflicting mass casualties. The consequences of such an attack could be so awful -- deaths conceivably reaching into the tens or hundreds of thousands -- that the government obviously has an obligation to prepare for the worst. At the same time, individual citizens need to be educated about how remote the danger is.

Among some 30 biological agents that have been studied as potential weapons, anthrax may be the most likely choice for terrorists because it is easier to acquire than most and is so lethal, killing 80 to 90 percent of all unvaccinated people who are not treated promptly. The anthrax spore is also very durable, able to survive for decades in the soil or other areas protected from direct sunlight.

However, anthrax does not spread from one victim to another. That limits its impact to those who inhale the aerosols. One authoritative group, using worst-case assumptions, estimated that a plane spreading anthrax over a big city might kill 100,000 people. Another suggested it might even be three million. But the only real-world precedent -- a leak of anthrax spores from a biological weapons plant in Russia in 1979 -- killed just 68 people, perhaps because the amount released was small.

Individuals can be protected by a vaccine given in a series of six doses followed by annual boosters, a cumbersome regimen. But the only vaccine currently available is for military use and even that is controversial, with some service members refusing to take it for fear of adverse side effects and because of doubts about its effectiveness. Nevertheless, alarmed citizens have been besieging the sole manufacturer to make the vaccine available, an impossibility since the company is unable to meet military needs.

Anthrax can also be treated by antibiotics, including Cipro, penicillin and doxycycline, if they are administered within days of exposure. Panicky citizens have been trying to obtain and hoard Cipro or other drugs to use if the unthinkable happens. From a pragmatic viewpoint, the rush on the drugstores of America is irrational -- every day, we run hundreds of risks that are greater than that of an anthrax attack, without taking any special precautions. From a societal viewpoint, it makes little sense to divert precious antibiotics to cope with a problem that is unlikely to materialize. Federal officials say that within 12 hours of an attack, they could rush in enough antibiotics to treat two million people for 60 days. On Sept. 11, they actually got antibiotics to New York within seven hours.

Smallpox is an even bigger worry for some experts because of the global pandemic it could trigger. Unlike anthrax, smallpox is contagious, spreading from person to person through the air, and it kills about 30 percent of unvaccinated victims.

The disease was eradicated from the globe in 1977, and routine vaccinations stopped in this country in 1972. By one estimate, more than 40 percent of the American public has not been vaccinated, and those who were vaccinated only once in earlier years are almost certainly now vulnerable again. Should smallpox be reintroduced in this country, it could move progressively through the population and, in today's highly mobile world, flash back to hit the rest of the planet as well.

However, the smallpox virus should be extremely difficult for a terrorist to get. Once the disease was eradicated, the World Health Organization made a concerted effort to concentrate all remaining samples of the virus in two laboratories, one in the United States and one in Russia. Those worried about smallpox say no one can be sure that all samples were really destroyed elsewhere, or that disaffected Russian scientists have not made the virus available to other countries. There are persistent rumors that rogue nations like Iraq and North Korea have clandestine supplies. Obviously, the most important defense against smallpox is better intelligence on just who has samples of the virus. If they are tightly guarded in the United States and Russia, the danger is minimal.

Fortunately smallpox, like all biological agents, presents formidable obstacles to those who would try to make and disperse it as a weapon. But since the World Trade Center attack, some analysts have been contemplating the possibility that suicidal terrorists might volunteer to be infected with the smallpox virus and move about in public, starting a chain of infection. Whether any terrorists would risk starting a pandemic that could travel back across the globe to infect their own friends and families, whether they would willingly choose a slow and agonizing death by disease, and whether once sick they would have the energy to start roaming the country is hard to imagine. But after Sept. 11, no one can rule it out.

There is no treatment for smallpox, but there is an effective vaccine. The United States currently has 15 million doses and has ordered an additional 40 million, to be delivered next year. That might be enough to contain an outbreak in a single city by vaccinating those most at risk of infection, but many experts believe the nation needs more than 100 million doses to truly be ready. The government plans to keep amassing the vaccine until it has enough for everyone in the country.

Virtually all experts agree that it would make no sense for most citizens to take the vaccine in advance of any smallpox outbreak. The threat is simply too remote and the vaccine has side effects that could kill or cause brain damage in some of those vaccinated. Prevention is something that must be handled by public health officials and the intelligence agencies.

Amid rising public concern, even hysteria, over the dangers of biological terrorism, it is important to strike a balance. Before worrying themselves sick, people should realize that the likelihood of a biological attack by terrorists is remote, given the technical difficulties of acquiring and spreading the disease organisms. Smallpox seems an especially unlikely threat, and if an attack were launched with anthrax, the chance that it would affect an enormous number of people seems extremely small. The most reasonable response for individual citizens is to demand that the government improve its intelligence capabilities and implement rational health policies that strengthen the nation's ability to cope with severe outbreaks of disease, whether natural or manmade.