Welcome news ! Single dose of swine flu vaccine may be enough

Australian vaccine maker CSL Inc. released new data showing its vaccine got what would be considered a protective immune response with a singe dose, and Swiss drug maker Novartis presented a study confirming a report from last week showing its vaccine worked at an even lower dose when boosted with an immune system compound called an adjuvant.

Both studies, published in the New England Journal of Medicine, may lay to rest fears about the logistical nightmare of trying to vaccinate hundreds of millions of people globally with two doses of H1N1 vaccine -- given a month apart -- in addition to a single recommended dose of seasonal influenza vaccine.

Last week China's Sinovac also reported its vaccine protected patients with a single dose.

The new H1N1 strain of flu, declared a pandemic in June, could eventually infect one third of the world's population, or 2 billion people, according to the World Health Organization.

Because it is a new strain, infectious disease experts had said people would likely need two doses to get full immunity against the virus. They are rushing to put in place vaccine programs as the weather cools in the Northern Hemisphere and the traditional flu season starts.