What Is Smallpox?

Smallpox is a highly contagious virus that can be spread through the air and infects 30% of the people who are exposed to it. Once infected, there is no cure. None of our current antiviral medications is effective. Smallpox can spread from person to person and through infected blankets, linens, and clothing.

Experts consider it a likely weapon of choice for use in a bioterrorist attack.

Symptoms don't start until about 12 days after exposure to the virus. At first, it's like the flu -- causing an under-the-weather feeling of fever, nausea, vomiting, headache, and backache. Then, severe abdominal pain and disorientation can set in, as small, round sores erupt all over the skin. About 30% of people who become infected will die, and survivors can be left with permanent scars.

Of course, vaccination can prevent smallpox infection. But the World Health Organization's worldwide vaccination campaign, begun in 1967, came to an end in 1980 when the disease was officially declared "eradicated." Here in the U.S., where smallpox was stamped out even earlier, childhood vaccination ceased in 1972.

There are only two official repositories of smallpox virus in the world: the CDC in Atlanta and the Russian State Research Center of Virology and Biotechnology in Koltsovo, Novosibirsk. Those supplies are used for scientific research and vaccine development.

These two sources, however, are not the only stashes of the deadly virus. The same year that worldwide vaccination ceased, the Soviet government began growing and stockpiling large quantities of smallpox virus, specially adapted for use in bombs and missiles.

Even before Sept. 11th, interest was rising in how prepared we are to face a bioterrorism attack. And now that the "unthinkable" has happened, bolstering our smallpox vaccine supply has become a priority. There are currently about 50 million vaccine doses worldwide -- with 5 million to 7 million here in the U.S. Experts say that even with an all-out manufacturing effort, it would take at least three years before there was sufficient supply to prevent an epidemic.