The U.S. Food and Drug Administration approved the long-awaited vaccines for the H1N1 "swine" flu virus this afternoon. It is expected to be available in a month at about 90,000 locations nationwide, the Associated Press reported

"We will have enough vaccine available for everyone," Kathleen Sebelius, Health and Human Services Secretary, said in an address to Congress today, the AP reports. The government, which does not expect everyone to get the vaccine, has an order out for 195 million doses, but only about 45 million are expected to be available by mid-October. The announcement from the National Institutes of Health (NIH) last week that one dose is sufficient to protect against the virus means supplies will be more robust than they might otherwise have been. Nevertheless, the government is prepared to order more if necessary.

The vaccines, which have been in clinical studies in the U.S. since June, are made by four different firms.

"The H1N1 vaccines approved today undergo the same rigorous FDA manufacturing oversight, product quality testing and lot release procedures that apply to seasonal influenza vaccines," Jesse Goodman, acting chief scientist at the FDA, said in a prepared statement.

Given the initially limited availability of the vaccine, the government still recommends that those who are most likely to have complications from the flu, including children and pregnant women, should be the first in line for the shots.

At least one million people in the U.S. have likely been infected with the virus since April, according to the Centers for Disease Control (CDC), and 593 people have died, including about 40 children. The seasonal flu infects from 5 to 20 percent of the U.S. population every year and kills about 36,000, according to the CDC. Unlike the seasonal flu, the H1N1 swine flu virus has been found to be contagious for about a week after symptoms have receded. Researchers are recommending people with the flu stay home for several days even after they start feeling better.

Image courtesy of iStockphoto/VCTStyle