If no smallpox attack occurs, it could very well be due to a successful vaccination campaign.

If a smallpox attack came tonight, he added, "There's no way the state and local health departments would be able to implement the plan."

A smallpox attack is, I hope, very unlikely.

A smallpox attack would strike parents of unvaccinated children with primal fear.

But war games are not reality, and history suggests that a real smallpox attack need not result in devastation.

The probability of a smallpox attack is low, officials say.

Our government has no information that a smallpox attack is imminent.

If people were worried about terrorism, a possible war with Iraq and the specter of smallpox attacks, they weren't showing it.

Opponents argue that the threat of a smallpox attack is theoretical, while the risks of the vaccine itself are very real.

That is too high a price, the researchers said, if the chance of a major smallpox attack is low.