TORONTO - U.S. studies have confirmed that only one dose of H1N1 vaccine will be needed to protect adults and seniors.
And the studies show that it's OK to give people both the pandemic flu shot and a seasonal shot at the same time.
Dr. Anthony Fauci of the U.S. National Institute of Allergy and Infectious Diseases says the study looking into co-administration of the two types of shots showed that the immune system of healthy adults had no problems mounting a response to both.
Fauci says trials of the H1N1 vaccine in adults shows there was no substantial gain in antibody levels after a second shot, meaning one shot of this vaccine is sufficient.
He says his institute is now launching new trials, studying the safety and effectiveness of the vaccine in people with asthma and pregnant women, children and adolescents with HIV.
The U.S. started its pandemic flu vaccine program this week, with 6.8 million doses available to the states by the end of this week.
?? The Canadian Press, 2009