The injection form of the vaccine is expected to arrive a week later. Vaccines are also expected to arrive in Orange County next week.
"It's going to be a little bit hit and miss," said Dr. Jonathan Fielding, director of the Los Angeles Department of Public Health.
"Not everybody's going to get it at the same time. It's coming from five different manufacturers, different types of vaccines are coming at different times, but increasingly during this month, there will be increase availability," he said.
Priority for the first shipment will be for health care workers, children, pregnant women and people with chronic health conditions. Doctors say pregnant women are 5 to 6 times more likely to get the swine flu, or develop serious complications.
Seniors aren't considered to be at great risk.
"One of the theories is that older Americans were treated or received a shot when we had the last great H1 N1 epidemic back in the fifties, and they were exposed to that and they have some leftover resistance," says Dr. Stephen Jones of Northridge Hospital Medical Center.
On Monday, 7 million doses are being scattered throughout several cities across the nation.
Health care workers in Memphis and Indianapolis will be among the first to be vaccinated.
"I think it's important for everyone to protect themselves. So that's like the first step that we should all take," said Francisca Alvarenga of Los Angeles.
But as many Americans anxiously await the arrival of the vaccine, not everyone is convinced they even need the shot.
A recent survey out of Harvard finds that 6 in 10 adults aren't sure they want the vaccine, and 4 in 10 parents aren't sure they'll get their children vaccinated at all.
"A lot of people already have it. I'm not really concerned about it," said Eric Benarouche from Los Angeles.
But many medical professionals say Americans need to be vaccinated now more than ever.
"This is clearly the most ambitious influenza vaccination program ever mounted in the United States or anywhere in the world," said Dr. William Schaffner from the Vanderbilt School of Medicine.
By the end of October, all doctors and health care providers who ordered the vaccine should have it.