Volunteers for the H1N1 vaccine test are one full week into the study. The clinical trials are necessary to determine how much of the vaccine should be in a standard dose. Dr. Paul Glezen is a professor of molecular virology at Baylor College of Medicine.
"The main thing is to look at the difference between one and two doses of the vaccine and to see if we can administer the seasonal vaccine with the pandemic H1N1 vaccine. As you know, they're two different vaccines."
Scientists are testing the vaccine in 200 adults. Glezen says they have plenty of volunteers betweenÎ¾the ages of 18 and 64, but they still need more participants 65 and older.
"There may be differences by age because some preliminary data from CDC shows that older people, particularly over 40 or even older, may have pre-existing antibodies to this virus which means that they've had experience with a virus similar maybe 40 years ago or something."
That means people who have previous exposure to a similar virus might only need one dose of the vaccine compared to those with no exposure who might need two. The next phase of the trials begins later this week when researchers begin testing the vaccine on children. They hope to have results ready in time to produce a vaccine for the public by the end of the year.
Laurie Johnson. KUHF-Houston Public Radio News.