AFP - The US Food and Drug Administration (FDA) Tuesday approved a swine flu vaccine keeping officials on track to begin a mass vaccination campaign by next month, Health Secretary Kathleen Sebelius said.
"I am pleased to report that today the Food and Drug Administration has approved applications for vaccine for the 2009 H1N1 virus for four of the (five) manufacturers of the US licensed seasonal influenza vaccine," Sebelius told US lawmakers.
The US government has purchased 195 million doses of swine flu vaccine and will make shots available free of charge starting next month, Sebelius said.
"The large scale 2009 H1N1 vaccine program will begin mid-October with small amounts of vaccine becoming available the first week of October," she said.
The fifth US manufacturer was also expected to be licensed, she added.
Shots for the A(H1N1) virus will be available "free of charge to the American people" but providers might charge a fee to administer them.
Vaccination will be on a voluntary basis, with priority given to five groups deemed to be at particular risk from the novel swine flu virus.
The US Centers for Disease Control and Prevention (CDC) has recommended that pregnant women, people in contact with infants, medical personnel, people between the ages of six months and 24 years old, and adults under the age of 65 with underlying medical conditions should be the first to get the shots.
That is about 160 million people in the United States -- which is less than the 195 million doses of vaccine purchased by the government, only about one third of which are expected to be ready by October.
The vaccine will be available as either a flu shot made with killed H1N1 virus, or as a nasal spray made with live, weakened virus, Sebelius said.
Clinical trials are under way to determine if there is "any harm" in having a seasonal flu vaccine -- which is already available -- at the same time as the vaccine for H1N1 influenza, said Sebelius.