21.   He noted that the vaccine occasionally has fatal side effects.

22.   Researchers in Uganda will monitor safety reactions, and immune system changes that would indicate whether the vaccine has anti-HIV potential.

23.   That is why new flu vaccines have to be developed each year.

24.   The researcher said the TB vaccine will have to be tested extensively on laboratory primates, such as monkeys, before testing could be conducted on humans.

25.   The standard flu vaccine has to be redesigned each year to counter new variants of the virus.

26.   The vaccine would have to meet standards set by the Food and Drug Administration.

27.   The vaccine has serious side effects for many people and would be expected to kill several hundred if it were given to all Americans.

28.   This proves that the vaccine has a very powerful effect.

29.   Vaccines can have side effects and that raises especially sticky litigation risks.

30.   In the other six cases, the vaccine had no effect, the report said.