Clinical trials suggest only one H1N1 vaccine dose may be needed in adults.

ABC World News (9/10, story 4, 2:10, Besser) reported that the New England Journal of Medicine...published results of a vaccine trial out of Australia" of "the new swine flu vaccine and it was done in adults. And what they found was that one dose of the vaccine was enough to give protective immunity." Previously, federal researchers "were saying you might need two," the CBS Evening News (9/10, story 6, 0:15, Couric) reported. The vaccine is expected to be ready by mid-October."

On its front page, the New York Times (9/11, A1, McNeil) reports that the results indicate "the vaccine supplies now being made will go twice as far as had been predicted," which means it may be possible to vaccinate "all the 159 million people that the Centers for Disease Control and Prevention estimate are in the high-risk groups." The first trials involved "a single 15-microgram dose in adults" and were conducted by CSL Limited, an Australian firm. CSL "is under contract to supply millions of doses to the United States government." Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, "said trials now under way under the sponsorship of the National Institutes of Health were showing that adults who got only a single dose were protected within 8 to 10 days, which he said 'corroborates and confirms the exciting data' reported in the Australian study."

The AP (9/11, Neergaard) reports that "scientists had feared that people of all ages would need two shots about a month apart because the new H1N1 strain is so genetically different from normally circulating flu strains that most of the population has little if any immunity."

The Washington Post (9/11, A3, Stein) adds that the "eagerly awaited findings mark the first results from a flurry of studies that scientists have been rushing to conduct to develop a swine flu vaccine. The findings indicate that plans to inoculate millions of Americans...and others worldwide could occur much more quickly and require far less vaccine than officials had feared." Dr. Fauci noted that if two doses were needed, "that would be a major strain on vaccine supplies nationally and globally." HHS plans to "release preliminary results Friday of its vaccine studies." Fauci said NIH's findings "are consistent with the Australian study involving 240 patients and show the response occurs even more quickly -- eight to 10 days -- than the 21 days that study found."

USA Today (9/11, Sternberg) reports that the Australian study "showed that nearly 97 percent of volunteers given a standard dose of the vaccine produced antibody levels that typically protect against flu infection, giving planners the welcome news that they may need less vaccine to save more lives." CNN (9/11) and Bloomberg News (9/11, Randall) also cover the story.