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San Bernardino County's public health director says they received 4,000 doses Tuesday just before noon. These doses are for those between the ages of two and 24, and for adults who care for children under six months.
Doctors report the new vaccine is being met with great demand, but also some dismay.
On day two of the largest vaccination campaign in U.S. history, demand is outstripping supply.
Top priority goes to health care workers, women who are pregnant, and those with chronic medical conditions, including diabetes and asthma. Many parents are not wasting any time getting to the clinic.
"My son's got asthma pretty bad, so it's important for us to try and be ahead of the curve a little bit," said parent Brian Crosby.
Because it's a live vaccine, health officials say these initial doses are targeted for children without underlying health conditions.
At least 14 states, including California, have received shipments. Public health officials say side effects, which include headaches and muscle cramps, are minor.
"This vaccine was developed using the same testing, the same timeline, the same safety standards in production that are used for the influenza vaccine every season," said ABC News senior health and medical editor Dr. Richard Besser.
Patients are inundating doctors' offices, wanting to know if the vaccine is necessary given that the symptoms seem to be mild.
Health experts are encouraging vaccination because the H1N1 has caused deaths. However, some doctors and other health care workers have expressed concern about a vaccine that has been rushed into production.
The CDC is trying to ease fears by releasing information about the vaccine trials. The agency says as of September 30 there have been no serious adverse events in the 3,000 people who have been tested.
Until everyone can get the vaccine, practicing basic personal hygiene may be the best weapon against the swine flu.
On Monday, Governor Arnold Schwarzenegger signed an executive order allowing state agencies to quickly hire medical staff, transport vaccine and acquire such items as hand sanitizers and paper masks.
The L.A. County Department of Public Health reports it will be receiving shipments of the the nasal vaccine next week.
The government has ordered 250 million doses of the vaccine, enough to inoculate half the country at a cost of $2 billion.