61.   Thompson said that companies making the vaccine were not free to sell it.

62.   To make the vaccine, the researchers have used the salmonella bacterium.

63.   Thompson would not disclose the names of the companies offering to make the vaccine.

64.   Traditional vaccines are made of proteins from microorganisms like viruses or bacteria or are made of killed or disabled microorganisms.

65.   To make a vaccine, researchers at a Florida-based company called Nabi Pharmaceuticals attached nicotine to a protein derived from the outer coat of a bacterium.

66.   Two other large drug companies, GlaxoSmithKline and Aventis Pharma, are also among the companies offering to make smallpox vaccine.

67.   Vaccines are made of dead or weakened germs.

68.   Wyeth-Ayerst stopped making that vaccine at the same time it dropped the tetanus shots, and a second supplier, Baxter Hyland, also exited the market.

69.   A Michigan plant that was making the vaccine has been closed and will require FDA approval before it can reopen.

70.   Additionally, because the strain has never posed such a threat, comparatively little vaccine has been made.