11.   Creating a vaccine is crucial because the parasite has begun developing resistance to drugs used to treat malaria, and even mosquitos that spread the disease are withstanding pesticides.

12.   Experts say this could present unexpected trouble for creating other vaccines for sexually transmitted diseases, such as AIDS.

13.   If the source of their protection can be identified, it could yield new clues for creating a vaccine against AIDS, scientists say.

14.   Substances used for legitimate purposes, such as creating a vaccine, can also be components of biological weapons.

15.   The idea would be to create a vaccine using a weakened version of HIV that is missing nef and probably other genes, as well.

16.   The scientists trying to create a vaccine to prevent AIDS suddenly seem optimistic, even bullish, words that have not been heard much in this perennially gloomy field.

17.   The vaccine is created using a live version of the virus.

18.   The goal of creating a vaccine that would immunize children against a slew of diseases is also feasible, Wirth said.