The USA is accumulating an abundant supply of smallpox vaccine, but health officials say they are not recommending that it be widely used- yet. The vaccine currently on hand, 16.8 million doses in a government stockpile and more than 80 million doses that drug maker Aventis Pasteur says it will add to that, is safe and effective but can cause problems. Many people develop painful swelling around the site of the inoculation, headache and nausea. In people with weakened immune systems, the live-virus vaccine can cause illness. And in 1 to 2 people per million, it can cause death.
Routine smallpox vaccination stopped in the USA in the early 1970s, and the last naturally occurring case of smallpox in the world was in 1977. The only known remaining stocks of virus are in two laboratories, one at the Centers for Disease Control and Prevention in Atlanta and the other in Russia. Bioterrorism experts fear that criminals could have illicit supplies of smallpox virus that could be used as a weapon of mass destruction.
All the factors should be taken into account, including the benefits of a mass immunization campaign, eliminating the threat of smallpox as a bioterrorist weapon, and the disadvantages, which include the vaccine's side effects. Scientists are working to develop newer and safer vaccines, but that takes time.