1.   The vaccine protects against Hepatitis B, a highly infectious virus.

2.   Although many scientists doubt that the vaccine will protect against infection by itself, some say it may be useful when combined with other types of vaccines.

3.   Another question is how long the vaccine will protect against chicken pox.

4.   A chilling discovery about the possible nature of a Soviet biological warfare agent has fueled a debate as to whether the current anthrax vaccine will adequately protect American troops.

5.   A critical gap in knowledge is whether a vaccine derived from one strain of HIV will protect against all the HIV strains being transmitted around the world.

6.   A novel vaccine has protected two chimpanzees that were deliberately injected with the AIDS virus, scientists said Tuesday.

7.   A new genetically engineered vaccine protected six out of seven US Army volunteers who were exposed to malaria-infected mosquitoes after inoculation.

8.   Advocates for people with AIDS and many scientists expressed hope that the vaccine would protect a large proportion of recipients.

9.   Friedlander said there was no way of knowing whether the American vaccine would protect against such a genetically changed organism, which probably kills by a different mechanism.

10.   Garner said there was no scientific evidence the vaccine would protect troops against airborne anthrax.